Haematology Flashcards

(188 cards)

1
Q

RFs for Hodgkins lymphoma

A

EBV, FH, young adults, 16-65, peak in 30s, M>F, HIV

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2
Q

What is Hodgkins lymphoma

A

B cell tumours, no apoptosis, divides uncontrollably, don’t produce Ig, usually surrounded by t cells

Contiguously spread rarely extranodal.

Classical
95%, Reed-Sternberg cells (2 cells fused, owl eyes). CD15/30
Nodular sclerosis: 70%, young adults, neoplastic inflam cells surrounded by collagen from fibroblasts, forming nodules, lacunar cells (RS cells with shrunken cytoplasm, nucleus appears as if in middle of lake).
Mixed: 20%, HIV, mixed inflam, background, eosinophils, neutrophils, plasma cells, histiocytes surrounding RS cells, good prognosis.
Lymphocyte rich: 5% RS cells surrounded by lymphocytes, best prognosis.
Lymphocyte poor: rarest, 30-37, no reactive lymphocytes, abundance of RS cells, HIV, worst prognosis.
Nodular lymphocyte predominant
M>F, 5%
CD20/45. No RS cells
Large groups of lymphocytes form nodules around lobulate-nucleated popcorn cells
Slow growing, highly curable.

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3
Q

Features of Hodgkins lymphoma

A

Painless cervical/ supraclavic/ mediastinal (cough, SVCS, abdo pain, dyspnoea) lymphadenopathy, rubbery, painful with alcohol.

Cytokine release: fever, drenching night sweats, weight loss. NS 50%, mixed cellularity/ lymphocyte depleted common

Pruritis

Hepatosplenomegaly

Tonsillar enlargement

Pel Ebstein fever: cyclical fever, periods of high + normal temp.

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4
Q

Complications of Hodgkins lymphoma

A

Nodular lymphocyte predominant: transformation to aggressive NHL.

Poor prognosis: >45, stage 4, Hb <10.5, lymphocyte coung <600/8%, male, albumin <40, WBC >150,000

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5
Q

Diagnosis of Hodgkins lymphoma

A
Ann Arbor 
1 LN/group of adjacent LN
>2 LN regions, both on same side of diaphragm
LN on both sides of diaphragm 
Liver/ spleen/ lungs/ bone marrow. 
A: no Sx other than pruritis 
B: B Sx
E: organs/ tissues beyond lymph system 
CT/PET scan 
Gallium scan: involved sites appear bright 
LN biopsy
↑LDH
Normocytic anaemia, eosinophilia 
FBC: ↓Hb, plts, WBC ↑↓
ESR: ↑
CXR: mediastinal mass, large mediastinal lymphadenopathy
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6
Q

Tx of Hodgkins lymphoma

A

Rituximab: NLP > binds CD20 induces apoptosis.

Classical: ABVD /BEACOPP + radio

NLP: early > radio, advanced, R-CHOP

R-CHOP: rituximab, cyclophosphamide, doxorubicin, vincristine, pred

BEACOPP: bleomycin etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, pred

ABVD: doxorubicin, bleomycin, vinblastine, radiotherapy.

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7
Q

RFs for NHL?

A

ataxia telangiectasia, >50, M>F. Wiskott-Aldrich, Chediak Higashi, Klinefelter, HTCL virus, H pylori, IS, HIV, AI disease, aromatic hydrocarbons eg benzene, radiation, pesticides,

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8
Q

What is Non-Hodgkins lymphoma?

A

80% B cell, 20% t cell
Usually LN can be extra-nodal
Small bowel lymphoma: small intestine, MALT, coeliac, intra epithelial T cell.

B cell
Most common, aggressive
CD20
Diffuse large B cell: most common. Aggressive. t(3,4) BCL6. Germinal/ activated b cell.
Follicular: slow growing, 2nd most common. Middle > later life, rare in childhood. T(14, 18) > BCL2 gene.
Burkitt: highly aggressive, commonest childhood malig, M>F. endemic (EBV, Africa, rapidly growing maxilla/ mandible tumour), sporadic (30% EBV, most marrow involvement, or abdo mass > ileo-ceacal), AIDs. T(8, 14) > MyC.
Mantle cell: aggressive, t(11, 14) > BCL1 > cyclin D1
Marginal zone: indolent, MALT (chronic inflam eg H pylori), LN/ spleen.
Lymphoplasmacytic: ↑age indolent, uncommon, bone marrow, LN spleen. Waldenstrom macroglobulinulinemia > neoplastic cells produce IgM, ↑blood viscoscity t(9,14)
Cutaneous: extranodal marginal/ follicle centre
Hairy cell leukaemia: BRAF mutations

T cell
Less freq
Angioimmunoblastic, extranodal natural killer/ T cell lymphoma nasal type enteropathy associated T cell lymphoma, anaplastic, periph T cell lymphoma.
Middle aged > elderly.
Adult t cell lymphoma: leukaemia, human t lymphotropic virus
Mycosis fungoides: t cell lymphoma of skin, resembles fungal infection, confined to skin. Long Hx, preceded by scaly pre-mycotic phase.

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9
Q

Features of NHL?

A

DLBC: intra-abdo disease, bowel Sx due to compression/ infiltration of GIT. 30% present at extranodal site as opposed to nodal disease with extranodal spread.

Burkitt: abdo mass, bone marrow involvement, CNS, kidney, testis.

Lymphoplasmacytic: anaemia Sx, hyper viscosity (headaches visual disturbances), Raynauds.

Cutaneous: single or clustered lesions
Angioblastic: fevers, rashes, electrolyte abnormalities

Mycosis fungoides: multiple erythematous lesions, plaques + tumours, when spreads to blood/ bone becomes Sezary syndrome.

Generalised erythroderma.

Painless lymphadenopathy, non-tender, rubbery, asymmetrical

B Sx: fever, drenching night sweats, weight loss, malaise

Waldeyer’s ring: oropharynx Dx, sore throat, obstructed breathing.

Splenomegaly: marginal zone

Hepatomegaly, jaundice

SOB: pleural involvement

Cough: mediastinal mass/ lymphadenopathy, pneumonia

Anaplastic: t(2,5)

MALT: T(11,18)

B Sx appear later in NHL than HL.

Testicular mass

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10
Q

Complications of NHL?

A

Bone marrow involvement: fatigue, weakness, anaemia, bleeding, infections.

Extra-nodal: bowel obstruction.
SCC, motor/sensory deficits.

Meningeal involvement: headache, mental status

Bone pain

Follicular, transform into more aggressive NHL.

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11
Q

Diagnosis of NHL?

A

Follicular: large plasmablasts/ immunoblasts. Diagnostic biopsy may not be represenetative esp if abdo mass but periph LN biopsied. Percut needle biopsy of abdo may reveal DLBCL transformation.

Burkitt: starry sky, stars (tangible bodies, macrophages with phagocytosed dead neoplastic cells), sky (dark neoplastic lymphocytes)

Mycosis fungoides: CD4 helper t cells, cerebriform nucleus (looks like brain).

CT/PET

LN biopsy, skin biopsy

Adverse prognostic factors: >60y/o, stage 3/ 4, ↑LDH, performance status, >1 extranodal site involved

FBC: thrombocytopenia, pancytopenia, lymphocytosis, pancytopenia

Blood smear: nucleated RBCs, left shift

Immunohistochemistry/ flow cytometry: determines tumour surface markers

Lymphoplasmacytic: large amounts of basophilic cytoplasm, nucleus contains spoke wheel like chromatin.

Mantle: cells have notched nuclei.

Hairy cell: dry tap on bone marrow aspiration due to fibrosis, CD11c marker, leucopenia.

Ann Arbor system

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12
Q

Management of NHL?

A

DLCB: Tx immediately, R-CHOP, radiotherapy

Follicular: R-CHOP

Burkitt: rituximab, cyclophosphamide, doxorubicin, vincristine, methotrexate.

Mantle: rituximab, R-CHOP

Marginal: H pylori eradication, prognosis good, 6 monthly endoscopy, if spread chemo.

Lymphoplasmacytic: in emergency lower paraprotein by plasmapheresis. Chemo + rituximab.

Cutaneous B cell: excision, radiation. Good prognosis. If multiple sites rituximab.

Angioblastic: responsive to CS or low dose alkylating agents.

Allopurinol for TLS.

T cell: CHOP > no rituximab as no CD20

High grade lymphoma has a worse prognosis but higher cure rate.

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13
Q

Summary of tumour lysis syndrome?

A

Rapid destruction of tumour cells, massive release of intracellular components, damage kidneys > renal failure

Features - V/N/D, Lethargy, Haematuria, Muscle cramps, Paraesthesia

Complications - Ca phosphate crystals obstruct renal tubules > AKI, urate nephropathy, Cardiac arrhythmias, Tetany

Diagnosis - ↑K, P, ↓Ca due to phosphate binding

Management - Prophylaxis: hydration, avoid NSAIDs, allopurinol.
Tx electrolyte abnormalities
Haemodialysis
Rasburicase
Fluids, ± loop diuretics to aid renal excretion of uric acid crystals.

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14
Q

What is acute lymphoblastic leukaemia?

A

Most common malignancy affecting children and accounts for 80% of childhood leukaemias.

Lymphoblasts accumulate in BM, suppression, prevent maturation.

peak incidence is at around 2-5 years of age
B>G

common ALL (75%), CD10 present, pre-B phenotype
T-cell ALL (20%)
B-cell ALL (5%)

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15
Q

RFS for ALL?

A

most common leukaemia in children. B > 3, T > 15-20. 2 peak incidences, 2-5 + >50. Down syndrome (>5), Klinefelter’s, radiation exposure, genetic, Hx of malig, Tx with chemo, smoking

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16
Q

Features of ALL?

A

Abrupt onset
Pleural effusion
Hyperuricaemia, TLS

anaemia: lethargy and pallor
neutropaenia: frequent or severe infections
thrombocytopenia: easy bruising, petechiae

bone pain (secondary to bone marrow infiltration)
splenomegaly
hepatomegaly
fever is present in up to 50% of new cases (representing infection or constitutional symptom)
testicular swelling

Thymus: palpable mass, airway compression
Lymphadenopathy
Orchidomegaly: unilat
Abdo pain: splenomegaly
Skin infiltration by blast cells
Renal enlargement: infiltration of renal cortex by blast cells

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17
Q

Poor prognostic factors for ALL?

A
age < 2 years or > 10 years
WBC > 20 * 109/l at diagnosis
T or B cell surface markers
non-Caucasian
male sex
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18
Q

Complications for ALL?

A

Meningeal infiltration: headache, vomiting, nerve palsies, nuchal rigidity, papilloedema

Bone pain, limp in young child

Focal neurological signs: CN 3/4/6/7 CNS leukaemia

DIC

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19
Q

Diagnosis of ALL?

A

Blood count: ↑lymphocytes, WBCs
BM smear: hypercellular bone marrow, lymphoblast domination >20%. T-ALL starry sky of phagocytosing macrophages.
Condensed chromatin, scant cytoplasm, small nucleoli
↓WCC until spill out causing ↑
↑LDH
CT: mediastinal mass, LN involvement/ CNS infiltration.
B-ALL: CD10/19/20
T-ALL: CD1/2/5/7/H
Terminal deoxynucleotidyl transferase: pos, distinguish from AML

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20
Q

Management of ALL?

A

Aggressive chemo: prophylactic injections into scrotum, CSF as chemo can’t cross BBB or testicular. Methotrexate

95% remission, 75% cute rate.

Tyrosine-kinase inhib: imatinib

Blood/plt transfusion

Poor prognostic factors: <2 or >10, WBC >20, T/B cell surface markers, non-Caucasian, M

Induction: pred/ dexamethasone + cyclophosphamide + vincristine + doxorubicin

Consolidation Tx

Rituximab if CD20

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21
Q

What is acute myeloid leukaemia?

A

Acute myeloid leukaemia is the more common form of acute leukaemia in adults. It may occur as a primary disease or following a secondary transformation of a myeloproliferative disorder.

Myeloblasts accumulate in BM, suppression > prevents maturation, normal haematopoiesis ↓

Acute promyelocytic: t(15,17) > disruption of retinoic acid receptor > promyelocytes accumulate (cells with heavy granulation in cytoplasm). Good prog Fusion of PML + RARα genes

T(8:21), (q22:q22), inv(16 (p12:q22), t(16, 16)(p13q22) t(15:17), (q22:q12).

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22
Q

RFs for AML?

A

adult (60), M>F, radiation, benzene, dark coloured hair dyes, smoking, alcohol, agricultural workers, pesticides, fertilisers, chemo (alkylating agents eg cyclophosphamide, melphalan, nitrogen mustard, latency 4-8yrs, topoisomerase inhibs (etoposide, teniposide) latency 1-3yrs), myeloprolif/ haematological disorders eg myelodysplastic synd, anaplastic anaemia, paroxysmal nocturnal haemoglobinuria, polycythaemia vera, essential thrombocytopenia, downs, Klinefelter’s, Patau’s. p53.

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23
Q

Features of AML?

A

Abrupt onset
Bone marrow failure = Anaemia, thrombocytopenia, neutropenia, splenomegaly, bone pain
Skin or testicular mass
Abdo pain

Sx less common in AML than ALL: bone pain, thymus mass/ airway compression, hepatosplenomegaly, lymphadenopathy, meningeal infiltration.

Sx more common in AML than ALL: skin (leukaemia cutis, nodular skin lesion, purple or gravy-blue colour), Sweet’s syndrome (fever, leukocytosis, tender erythematous well demarcated papules + plaques which show dense neutrophilic infiltrates), pyoderma gangrenosum. Gum swelling, granulocytic sarcomas.

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24
Q

Poor prognostic features of AML?

A

> 60 years

> 20% blasts after first course of chemo

cytogenetics: deletions of chromosome 5 or 7

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25
Complications of AML?
``` DIC Death in 2 mnth if untreated High relapse rate Mediastinal or thymic infiltration: SVCS, airway compromise Febrile neutropenia Leukostasis: ↑blood viscosity ```
26
Diagnosis of AML?
Blood smear: granulated + Auer rod content of blasts Bone marrow smear: ↑myeloblasts >20%, auer rods. Large nucleus, prominent nucleoli, more cytoplasm visible than in ALL. Bone marrow hypercellularity. ↑WCC Acute promyelocytic: abnormal WBCC, bi lobed nuclei, hyper granulated blasts, bundles of auer rods. DIC + thrombocytopenia at presentation. FBC: anaemia, macrocytosis, leukocytosis, neutropenia, thrombocytopenia, ↓reticulocytes. ``` Classification - French-American-British (FAB) MO - undifferentiated M1 - without maturation M2 - with granulocytic maturation M3 - acute promyelocytic M4 - granulocytic and monocytic maturation M5 - monocytic M6 - erythroleukaemia M7 - megakaryoblastic ```
27
Management of AML?
Cytarabine, daunorubicin, idarubicin Stem cell transplant APML: tretinoin, arsenic > causes blasts to differentiate,
28
What is chronic lymphocytic leukaemia?
Chronic lymphocytic leukaemia (CLL) is caused by a monoclonal proliferation of well-differentiated lymphocytes which are almost always B-cells (99%). It is the most common form of leukaemia seen in adults. Mature, functionally abnormal B lymphocytes in BM/ blood. Escape PCD + undergone cell cycle arrest in GO/G1. Suppression. 99% B cells, full maturation + apoptosis prevented, defective, non functional lymphocytes. Premalig: monoclonal B cell lymphocytosis, where less than requires no of B cells for CLL diagnosis. CD19/20 + CD5 B cells
29
Features of CLL?
late onset B Sx - fever, chills, night sweats, fatigue, WL, anorexia anaemia, thrombocytopenia, neutropenia bone pain, hepatosplenomegaly, lymphadenopathy meningeal infiltration thymus mass - airway compression often none: may be picked up by an incidental finding of lymphocytosis constitutional: anorexia, weight loss bleeding, infections lymphadenopathy more marked than chronic myeloid leukaemia
30
Diagnosis of CLL?
full blood count: lymphocytosis anaemia blood film: smudge cells (also known as smear cells) immunophenotyping is the key investigation LN biopsy - prolif centres, lymphocyte infiltration Coombs test - positive if haemolytic present Rai and Binet staging system
31
RFs for CLL?
most common leukaemia in adults, M>F, >60, white, FH, agent orange exposure
32
Complications of CLL?
Abnormal Ig secretion: hypogamma globulinemia, AI haemolytic anaemia Richter syndrome: progresses to aggressive lymphoma eg DLBC, LN swelling, fever w/o infection, WL, night sweats, nausea, abdo pain
33
Management of CLL?
Median survival 10 yrs Chemo Immunotherapy Radiation Bone marrow transplant Tx if: symptomatic, immunoglobulin genes unmutated, 17p deletion, marrow failure, recurrent infection, splenomeg/ lymphadenopathy, progressive Dx (doubling of lymphocyte count in 6mnths), systemic Sx, haemolysis or AI cytopenias.
34
What is chronic myeloid leukaemia?
Prolif of mature granulocytes/ precursors, accumulate in BM Philadelphia Chr: t(9:22) BCR-ABL1 fusion. Strong tyrosine kinase activity
35
RFs for CML?
adult, >40, M, radiation, benzene
36
Features of CML?
60-70 years Gout, purine breakdown, TLS anaemia, WL, sweating, splenomegaly Chronic phase: 85% at time of diagnosis. Leucocytosis (pred neutrophils), fatigue, WL, loss of energy, fever, sweats, pallor, abdo discomfort, malaise, headache, priapism. Blast count <10% Accelerated: >20% basophils in blood/BM, 10-19% myeloblasts in blood/BM, anaemia, SOB, bleeding, petechiae, ecchymosis, retinal haem, epistaxis, hepatosplenomeg, lymphadenopathy, arthralgia, sternal tenderness (BM expansion of sternum). Blast crisis: terminal phase, rapid progression, >20% myeloblast in blood/BM. Sig splenomegaly. ↑anaemia, thrombocytopenia, basophilia. Bone pain, fever.
37
Complications of CML?
may undergo blast transformation (AML in 80%, ALL in 20%)
38
Diagnosis of CML?
``` ↑granulocytes > basophils, eosinophils, neurophils, WBCC WBCs bigger, more mature + blast like. ↑urate, B12, K, LDH ↓Plt Normochromic normocytic anaemia BM biopsy: hypercellularity, granulocytic hyperplasia Karyotypic analysis: BCR-ABL1, t(9,22). Pseudo Gaucher cells in marrow ↓leukocyte alkaline phosphatase ```
39
Management of CML?
``` Tyrosine kinase inhib: imatinib Hydroxycarbamide Hydroxyurea IFNα Bone marrow transplant ```
40
Summary of hairy cell leukaemia?
a chronic and rare form of adult leukemia Prolif of abnormal B or very rarely T cells which accumulate in BM + spleen ``` Features - gradual onset, Anaemia Fever Weight loss, weakness Splenomegaly, lymphadenopathy neutropenia, thrombocytopenia, low monocyte counts ``` Diagnosis - Blood/BM film: irregular outline due to presence of filament like cytoplasmic projections (hairy rim), immunophenotyping, bone marrow biopsy ``` Management - Purine analogues 2 chloradenosine acetate Pentostatin Cladribine Rituximab IFN alpha ```
41
What is multiple myeloma?
a haematological malignancy characterised by plasma cell proliferation It arises due to genetic mutations which occur as B-lymphocytes differentiate into mature plasma cells. MM is the second most common haematological malignancy
42
Presentation of MM?
median age of onset - 70 yrs CRABBI Calcium - Hypercalcaemia occurs as a result of increased osteoclast activity within the bones This leads to constipation, nausea, anorexia and confusion Renal - Monoclonal production of immunoglobulins results in light chain deposition within the renal tubules - This causes renal damage which presents as dehydration and increasing thirst - Other causes of renal impairment in myeloma include amyloidosis, nephrocalcinosis, nephrolithiasis Anaemia - Bone marrow crowding suppresses erythropoiesis leading to anaemia - This causes fatigue and pallor Bleeding - bone marrow crowding also results in thrombocytopenia which puts patients at increased risk of bleeding and bruising Bones - Bone marrow infiltration by plasma cells and cytokine-mediated osteoclast overactivity creates lytic bone lesions - This may present as pain (especially in the back) and increases the risk of fragility fractures - SCC pain Infection - a reduction in the production of normal immunoglobulins results in increased susceptibility to infection
43
Investigations for MM?
Bloods - anaemia, thrombocytopenia, raised urea and creatinine, raised calcium peripheral blood film - rouleaux formation serum or urine protein electrophoresis - raised concentrations of monoclonal IgA/IgG proteins will be present in the serum. In urine known as Bence Jones proteins bone marrow aspiration and trephine biopsy - confirms diagnosis if number of plasma cells is significantly raised whole-body MRI - surgery skeleton for bone lesions Xray - rain drop skull - due to bone lysis Symptomatic multiple myeloma is defined at diagnosis by the presence of the following three factors: - Monoclonal plasma cells in the bone marrow >10% - Monoclonal protein within the serum or the urine (as determined by electrophoresis) - Evidence of end-organ damage e.g. hypercalcaemia, elevated creatinine, anaemia or lytic bone lesions/fractures
44
Management of MM?
It is important to accurately diagnose multiple myeloma, as unlike its pre-malignant counterparts (Monoclonal gammopathy of undetermined significance and Smoldering myeloma), treatment must begin immediately due to the risk of complications occurring as a result on end-organ damage. Myeloma is a chronic relapsing and remitting malignancy which is currently deemed incurable. Management aims to control symptoms, reduce complications and prolong survival. treatment begins with induction therapy: For patients who are suitable for autologous stem cell transplantation* induction therapy consists of Bortezomib + Dexamethasone For patients who are unsuitable for autologous stem cell transplantation*, induction therapy consists of Thalidomide + an Alkylating agent + Dexamethasone After completion of treatment, patients are monitored every 3 months with blood tests and electrophoresis. Many patients do relapse after initial therapy. If this occurs the 1st line recommended treatment is Bortezomib monotherapy Autologous transplant: remove own SC prior to chemo + replaced after chemo
45
Complications of MM?
Pain: treat with analgesia (using the WHO analgesic ladder) Pathological fracture: Zoledronic acid is given to prevent and manage osteoporosis and fragility fractures as these are a large cause of morbidity and mortality, particularly in the elderly. Infection: patients receive annual influenza vaccinations. They may also receive Immunoglobulin replacement therapy. VTE prophylaxis Fatigue: treat all possible underlying causes. If symptoms persist consider an erythropoietin analogue.
46
RFs for MM?
alcohol consumption, obesity, radiation exposure, petroleum exposure, FHx, monoclonal gammopathy can progress to MM (initial conc of serum monoclonal protein sig predictor of progression, other prognostic factors< IgA or IgM monoclonal protein, BM plasmacytosis, bence jones proteinuria, ↓in polyclonal serum immunoglobulin, ↑ESR.
47
Causes of microcytic anaemia?
``` Find those small cells last: Fe def Thalassaemia minor Sideroblastic Chronic disease Lead poisoning ```
48
What is iron deficiency anaemia?
Microcytic, hypochromic ↓Fe for Hb synthesis, impaired erythropoiesis Most absorption in proximal SI, duodenum + jejunum.
49
Causes of iron deficiency anaemia?
Low intake: EDs (e.g. pica, anorexia, bulimia), diet restrictions (e.g. vegan), food insecurity Low absorption: celiac, surgical resection of GIT, bariatric surgery, XS dietary Ca, tannates, oxalates, gastrectomy/ achlorhydria, H pylori ↑need: pregnancy, lactation ↑growth: infants, children, adolescents Overt loss: haematemesis, trauma, heavy menses, haematuria, multiple blood donations, haemodialysis Occult: GI bleed (e.g. peptic ulcer, tumour), vascular lesions (e.g. haemorrhoids), hookworm/other helminthic infections
50
Features of iron deficiency anaemia?
Pallor Fatigue, activity intolerance, exertional dyspnoea, angina Palpitations, ↑HR, ↑CO, ↑RR Selective shunting of blood to vital organs eg skin to kidneys Glossitis: red, beefy tongue Angular stomatitis: sores in corner of mouth Cheilosis: scaling, fissuring: dryness, lip scaling Koilonychia: spoon-shaped, concave nails. Brittle hair + nails. Hair loss Oesophageal stricture + dysphagia Gastric atrophy, gastritis, absent/↓ acid secretion in stomach Blue sclerae Obsessive consumption of ice. Pica = abnormal craving, for non food substances eg dirt, ice, paint or clay RLS Post cricoid webs
51
Complications of iron deficiency anaemia?
High ouput HF Angina Cardioresp failure Impaired growth/ development Infections.
52
Diagnosis of iron deficiency anaemia?
↓ RBCC, low/normal reticulocytes, ↓ Hb, haematocrit. 🡩RDW (>14.6%) Hypochromic-microcytic erythrocytes ↓MCV, MCH, MCHC Blood smear: central pallor, target cells. Poikilocytosis (abnormally shaped), pencil cells. ↓iron, ferritin, transferrin saturation ↑total iron binding capacity + transferring receptors. Older pt: malig til proven otherwise Endoscopy to rule out malig in males + post menopausal females
53
Management of iron deficiency anaemia?
Ferrous sulfate, furmarate or gluconate. SE = constipation, black stools. Nausea, diarrhoea, faecal impaction. Continue for 3mnth after def corrected to replenish stores. Ascorbic acid: aid dietary absorption Parenteral iron: dextrate/sucrose, severe persistent anaemia, intolerance of PO iron, malabsorption ↑ dietary iron: heam > meat absorbed better than non haem eg eggs, legumes, nuts. Dark leafy vegetables. Blood transfusion Levothyroxine, Ca/ bisphosphonates, Quinolones, tetracyclines.
54
Summary of lead poisoning anaemia?
Lead exposure, toxicity, interferes with enzymatic steps in haem pathway, ↓Hb synthesis, impairs Na/K ATPase in erythrocytes > haemolysis. RF: water contaminated with industrial waste/ from lead pipes. Leaded paint. Older homes. Breathing industrial emissions (smelters, refineries, battery manufacturing, recycling), food/beverages from lead glazed ceramics. Small hypochromic RBCs Dyspnoea Activity intolerance Lead toxicity: abdo pain, headache, difficulty concentrating, muscle/joint, confusion, ataxia. Peripheral neuropathy (mainly motor), constipation, blue lines on gum margin. ``` Ix - ↑ serum blood lead level Basophilic stippling Clover leaf morphology ↓/normal MCV ↓ mean MCH Haemolysis: ↑ indirect bilirubin, LDH, ↓ haptoglobin ↑urinary coproporphyrin ``` ``` Tx - Eliminate exposure Chelation therapy: dimercaptosuccinic acid (DMSA, aka succimer), CaNa2EDTA D-penicillamine EDTA Dimercaprol ```
55
What is thalassaemia?
People with thalassaemia produce either no or too little haemoglobin AR, microcytic hypochromic, rigid less deformable membranes > extravascular haemolysis, phagocytosis by reticuloendothelial macrophages. Deficient α/β chains > imbalanced, aggregate + precipitate > unstable Hb tetramer.
56
What is alpha thalassaemia?
deficiency of alpha chains in haemoglobin 2 separate alpha-globulin genes on each Chr 16 If 1 or 2 alpha globulin alleles are affected then the blood picture would be hypochromic and microcytic, but the Hb level would be typically normal If are 3 alpha globulin alleles are affected results in a hypochromic microcytic anaemia with splenomegaly. This is known as Hb H disease If all 4 alpha globulin alleles are affected (i.e. homozygote) then death in utero (hydrops fetalis, Bart's hydrops) Minima: carrier, no Sx 1 gene missing Minor: trait, mild anaemia, 2 genes missing. HbH disease: 3 genes missing, mild anaemia. Major: 4 genes missing, hydrops fetalis, Hb Barts (γ tetramer), incompatible with extrauterine life.
57
What is beta thalassaemia?
Absence of beta globulin chains Point mutation in Chr11 Minor: 1 gene, trait. Asymptomatic carrier /mild hypo chromic, microcytic anaemia, ↑HbA2 (2 α + 2 delta). No haemolysis Intermedia: 2 genes. Moderate anaemia Sx, may be transfusion dependent in later life. Haemolysis: splenomeg + gall stones. Major: no β globin trains produced, transfusion dependent, Cooley’s anaemia. Presents once fully switched from fetal Hb few mnths of life, FTT + hepatosplenomegaly. Microcytic anaemia, HbA2 and HbF raised, HbA absent
58
Management of thalassaemia
Beta- thalassaemia major - repeated transfusion - leads to iron overload (organ failure) so iron chelation therapy (desferritoxamine) is important Folic acid Splenectomy Blood transfusions >9g.dL Allogenic haematopoietic cell transplantation
59
Features of thalassaemia?
Pallor, fatigue, activity intolerance Tachycardia, ↓BP, arrhythmias Chronic haemolysis: jaundice, dark urine, hepatosplenomeg Failure to gain weight Large head, frontal + parietal bossing, chipmunk facies, misaligned teeth.
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Diagnosis of thalassaemia?
β thalassaemia major: microcytic anaemia, ↑reticulocytes. ↑HbA2 + HbF. Absent HbA. Extramedullary haematopoiesis: hepatomeg, bone expansion, XR > hair on end of bones as marrow expands into cortical bone. ↑reticulocytes ↑WBC > generalised haematopoietic hyperactivity, all ↓ as spleen enlarges. MCHC ↑ related to erythrocyte dehydration ↓MCV ↑RCDW Blood smear: poikilocytosis (teardrop shaped cells), anisocytosis, erythroblasts (nucleated RBCs), target cells. Inclusions (precipitated globin chains), basophilic stippling Haemolysis: ↑LDH, UBR, ↓haptoglobin ↑iron, transferrin saturation, ferritin. β thalassaemia minor: microcytosis often disproportionate to anaemia α thalassaemia: Heinz bodies. Target cells
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What is sideroblastic anaemia?
condition where iron available but red cells fail to completely form haem, whose biosynthesis takes place partly in the mitochondrion. This leads to deposits of iron in the mitochondria that form a ring around the nucleus called a ring sideroblast. It may be congenital or acquired. Congenital cause: delta-aminolevulinate synthase-2 deficiency ``` Acquired causes myelodysplasia alcohol lead anti-TB medications ```
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Features of sideroblastic anaemia?
Syndromic: exocrine pancreatic insuff, hepatic/ renal failure, sensorineural deafness, myopathy Fatigue, dyspnoea, palpitations, pallor Mild jaundice if haemolysis significant
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Investigations for sideroblastic anaemia?
full blood count - hypochromic microcytic anaemia (more so in congenital) - low reticulocyte count iron studies (haemochromatosis) - high ferritin - high iron - high transferrin saturation blood film - basophilic stippling of red blood cells, anisocytosis, poikilocytosis, hypochromic, iron containing inclusions (Pappenheimer bodies), bone marrow - Prussian blue staining will show ringed sideroblasts
64
Management of sideroblastic anaemia?
supportive treat any underlying cause Via B6 pyridoxine may help Chelation - deforxamine
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Complications of sideroblastic anaemia?
Iron overload > haemochromatosis Anaemia induced acceleration of erythropoiesis > erythroid hyperplasia of BM ↑risk of infection Acute leukaemia
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Causes of normocytic anaemia
Insuff production of erythrocytes: Anaemia of chronic disease CKD Anaplastic anaemia Haemolytic anaemia
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Causes of anaemia of chronic disease?
Infection, RA, malig, CKD, IBD, TB, endocarditis, hypopit/thyroid/adrenal ↓iron release from BM to developing erythroblasts, inadequate EPO response to anaemia, ↓RBC survival Inhibition of erythropoiesis, ↓erythrocyte lifespan
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Features of anaemia of chronic disease?
Hypoxia, pallor, fatigue, dyspnoea, activity intolerance Sx of underlying condition
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Investigations of anaemia of chronic disease?
↓Hb, iron, (TIBC), transferring sat, reticulocyte count. ↑/normal ferritin as acute phase protein. ↑ESR/CRP/IL6 ↓EPO Normochromic normocytic or hypochromic microcytic BM: ↑iron in macrophages, erythroid precursors.
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Management of anaemia of chronic disease?
Treat cause Renal failure: recombinant EPO Supplemental iron: IV iron due to systemic inflam Transfusion
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What is aplastic anaemia?
Characterised by pancytopenia (low RBC, WBC and plts) and a hypoplastic bone marrow due to BM hypoplasia/aplasia ↓reduction in no of pluripotent SC, inefficiency with remaining ones. Peak incidence of acquired = 30 years old
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Features of aplastic anaemia?
normochromic, normocytic anaemia leukopenia, with lymphocytes relatively spared thrombocytopenia may be the presenting feature acute lymphoblastic or myeloid leukaemia a minority of patients later develop paroxysmal nocturnal haemoglobinuria or myelodysplasia Fanconi - ↑risk of AML, neurological Sx, short stature, Café Au Lait spots. Hearing loss Dyskeratosis congenita: osteoporosis, premature hair loss/ premature greying, hyperhidrosis, dysphagia due to oesophageal stricture, extensive dental carries or tooth loss. Schwachman-Diamond: steatorrhea, skeletal dysplasia GATA2: monocytopenia, non TB mycobacterial infection, pulmonary alveolar proteinosis, congen lymphoedema, Emberger syndrome. Hearing loss, persistent warts.
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Causes of aplastic anaemia?
idiopathic congenital: Fanconi anaemia, dyskeratosis congenita drugs: cytotoxics, chloramphenicol, sulphonamides, phenytoin, gold toxins: benzene infections: parvovirus, hepatitis radiation
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Investigations for aplastic anaemia?
Prolonged bleeding time ↓Hb, haematocrit, neutrophils, plts reticulocytes. Normal erythrocyte morphology BM: hypocellular, ↑fat spaces, some lymphocytes, plasma cells, stromal elements eg blastoid cells, no ↑ in blasts/ dysplasia. Leukopenia with lymphocytes relatively spared.
75
Management of aplastic anaemia?
Antimicrobials for infections Stem cell transplant Transfusions: plts, RBCs. ↑risk of alloimmunisation, graft rejection after BM transplant. GFs: granulocyte colony stimulating factor for freq/ severe infections, thrombopoietin receptor agonists with immunosuppressive therapy. IS therapy: lymphocyte immunoglobulin, anti-thymocyte globulin, methylprednisolone, ciclosporin.
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What is haemolytic anaemia?
↑destruction of red cells + ↓circulating lifespan. BM unable to compensate for loss. Extravascular: within reticuloendothelial system, removed from circulation as are defective. Intravascular: within BVs eg trauma, complement fixation or extrinsic factors
77
Causes of haemolytic anaemia?
RBC membrane defect: hereditary spherocytosis, hereditary elliptocytosis Thalassaemia, sickle cell RBC met defects: G6PD def, pyruvate kinase def AI, transfusion reactions, drug induced Paroxysmal nocturnal haemoglobinuria, microangiopathic, march haemoglobinuria Infections (e.g. malaria, babesiosis, bartonellosis, leishmaniasis, clostridium perfingens, Haem influenzae B), drugs/ chemicals (cephalosporins, penicillin, quinine derivatives, NSAIDs, naphthalene or fava beans), hypersplenism, trauma, exceptional exertion (circulatory trauma), liver disease. Lymphoprolif disorders Mechanical prosthetic heart valves
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Features of haemolytic anaemia?
Jaundice Hepatosplenomeg Pallor, fatigue, activity intolerance, SOB, dizziness Orthostasis IV: haemoglobinuria, iron def EV: jaundice, splenomeg, gallstone formation. Episodic dark urine
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Investigation for haemolytic anaemia?
↓haptoglobin Polychromasia: purplish appearance of RBC due to reticulocytes. ↑UBR, urinary urobilinogen, reticulocytes, LDH Normocytic normochromic anaemia Marrow hyperplasia ↑MCHC Blood film: polychromasia, macrocytosis, spherocytes, elliptocytes, fragmented cells or sickle cells. Bite or spur cells. Schistocytes (helmet cells) in IV haemolysis G6PD: Heinz bodies Pyruvate kinase def: burr cells, echinocytes Urine: Perl’s reaction (detects high levels of hemosiderin due to Hb), Schumm’s test can also show high Hb levels.
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What is AI haemolytic anaemia?
Autoantibodies against antigens on RBC surface Divided into warm and cold, types, according to at what temperature the antibodies best cause haemolysis. It is most commonly idiopathic but may be secondary to a lymphoproliferative disorder, infection or drugs.
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Investigations for AI haemolytic anaemia?
``` general features of haemolytic anaemia - anaemia - reticulocytosis - low haptoglobin - raised lactate dehydrogenase (LDH) and indirect bilirubin ``` blood film: spherocytes and reticulocytes specific features of autoimmune haemolytic anaemia - positive direct antiglobulin test (Coombs' test).
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Summary of warm AIHA?
Warm is the most common type of AIHA. In warm AIHA the antibody (usually IgG) causes haemolysis best at body temperature and haemolysis tends to occur in extravascular sites, for example the spleen. Causes of warm AIHA - idiopathic - autoimmune disease: e.g. systemic lupus erythematosus* - neoplasia (lymphoma, chronic lymphocytic leukaemia) - drugs: e.g. methyldopa Management - treatment of any underlying disorder - steroids (+/- rituximab) are generally used first-line
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Summary of cold AIHA?
The antibody in cold AIHA is usually IgM and causes haemolysis best at 4 deg C. Haemolysis is mediated by complement and is more commonly intravascular. Features may include symptoms of Raynaud's and acrocynaosis. Patients respond less well to steroids Causes of cold AIHA neoplasia: e.g. lymphoma infections: e.g. mycoplasma, EBV often no Tx required
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Summary of paroxysmal AIHA?
children Donath-Landsteiner, viral/ bacterial infections, dark urine in morning. jaundice, haemoglobinuria, anaemia after infection, pain in legs + back following cold exposure.
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What is G6PD deficiency?
is the commonest red blood cell enzyme defect. It is more common in people from the Mediterranean and Africa and is inherited in an X-linked recessive fashion. Many drugs (antimalarials (primaquine), ciprofloxacin, sulph-group drugs. (sulphonamides, sulphasalazine, sulfonylureas) can precipitate a crisis as well as infections and broad (fava) beans G6PD is the first step in the pentose phosphate pathway, which converts glucose-6-phosphate→ 6-phosphogluconolactone this reaction also results in nicotinamide adenine dinucleotide phosphate (NADP) → NADPH ↓ G6PD → ↓ reduced NADPH → ↓ reduced glutathione → increased red cell susceptibility to oxidative stress
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Features of G6PD deficiency?
neonatal jaundice is often seen intravascular haemolysis gallstones are common splenomegaly may be present Heinz bodies on blood films. Bite and blister cells may also be seen
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Diagnosis of G6PD deficiency?
Damage to Hb within cells > Heinz bodies. Splenic macrophages attempt to remove Heinz bodies > bite, blister cells ↓Hb, haptoglobin Neg coombs ↑BR, LDH Reticulocytosis G6PD enzyme assay levels should be checked around 3 months after an acute episode of hemolysis, RBCs with the most severely reduced G6PD activity will have hemolysed → reduced G6PD activity → not be measured in the assay → false negative results Newborn screening Fluorescent spot test: glucose 6 phosphate + NADP added to haemolysate of RBCs > fluorescence of NADPH Methaemoglobin reduction test: methylene blue measures transfer of hydrogen ions from NADPH to methaemoglobin > indirectly estimates NADPH generation by G6PD.
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Management of G6PD deficiency?
Folic acid supplements Eliminate triggers Phototherapy Haemolytic ep: hydration, transfusions Splenectomy not beneficial
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Summary of haemolytic disease of newborn?
Fetomaternal haem > exposes maternal circulation to antigens on RBCs > formation of maternal IgG against fetal RBCs > cross placenta > agglutination, haemolysis. Causes of maternal sensitisation: delivery, abortion, maternal trauma, CVS, amniocentesis, antenatal haem, idiopathic RF: blood group incompatibility. ABO incompatibility: mild to mod hyperbilirubinemia within 1st 24hrs of life, mild to mod anaemia. Rh incompatibility: kernicterus, hyperbilirubinaemia. Sx anaemia: pallor, lethargy, ↑HR/RR. Hydrops fetalis. IUGR ``` Complications: Anaemia Hyperbilirubinemia Kernicterus Growth restriction Hydrops fetalis Erythroblastosis fetalis ↑immature RBCs in fetal circulation ``` Ix: Doppler USS: restriction, hydrops. Antenatal: pos indirect antiglobulin test (IAT, indirect Coombs, IgG), Kleihauer-Betke (pos if fetomaternal haem), percut umbilical blood sampling (measures Hb, haematocrit, identifies fetal blood type). Spectrophotometric amniotic fluid analysis: ↑BR if haemolysis has occurred. Postnatal: blood typing pos direct antiglobulin (DAT, direct Coombs test, maternal Ig on RBC), ↑BR, ↓Hb, haematocrit, RBCs, reticulocytes. Blood smear: haemolysis, polychromasia, microspherocytosis. ``` Haematopoietic agents: epoetin alfa/ darbepoetin, iron supplements. Iron supplements RBC transfusion Exchange transfusion Phototherapy IV immunoglobulin: ↓haemolysis ```
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What is hereditary spherocytosis?
most common hereditary haemolytic anaemia in people of northern European descent autosomal dominant defect of red blood cell cytoskeleton the normal biconcave disc shape is replaced by a sphere-shaped red blood cell red blood cell survival reduced as destroyed by the spleen mutation in spectrin, ^ Na permeability
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Presentation of hereditary spherocytosis?
often asymptomatic failure to thrive jaundice, gallstones anaemia Sx splenomegaly MCHC elevated complications: - aplastic crisis precipitated by parvovirus infection degree of haemolysis variable - megaloblastic anaemia - folate deficiency - neonatal incterus, hydrops fetalis, fetal death
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Diagnosis of hereditary spherocytosis?
patients with a family history of HS, typical clinical features and laboratory investigations (spherocytes, raised mean corpuscular haemoglobin concentration [MCHC], increase in reticulocytes) do not require any additional tests ↓Hb, haptoglobin ↑reticulocytes, RDW, BR, LDH, MCHC Spherocytes (round, lack central pallor) schistocytes (RBC fragment) Osmotic fragility test if the diagnosis is equivocal the BJH recommend the EMA binding test and the cryohaemolysis test for atypical presentations electrophoresis analysis of erythrocyte membranes is the method of choice
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Management of hereditary spherocytosis
acute haemolytic crisis: - treatment is generally supportive - transfusion if necessary longer term treatment: - folate replacement - splenectomy - wait until after childhood as can prevent response to fatal infections, life long penicillin prophylaxis - phototherapy
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What is paroxysmal nocturnal haemoglobinuria
is an acquired disorder leading to haemolysis (mainly intravascular) of haematological cells. It is thought to be caused by increased sensitivity of cell membranes to complement due to a lack of glycoprotein glycosyl-phosphatidylinositol (GPI). Patients are more prone to venous thrombosis X linked. Nocturnal haemolysis, haemolytic anaemia, BM failure, thrombosis PIGA gene mutation, required for synthesis of GPI on cell surface, anchors glycoproteins on surface protecting cell from lysis. Def = complement mediated IV haemolysis. GPI can be thought of as an anchor which attaches surface proteins to the cell membrane complement-regulating surface proteins, e.g. decay-accelerating factor (DAF), are not properly bound to the cell membrane due a lack of GPI thrombosis is thought to be caused by a lack of CD59 on platelet membranes predisposing to platelet aggregation
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Features of paroxysmal nocturnal haemoglobinuria
- haemolytic anaemia - variable Sx according to degree of GPI loss - red blood cells, white blood cells, platelets or stem cells may be affected therefore pancytopaenia may be present - intermittent episodes of haemoglobinuria: classically dark-coloured urine in the morning (although has been shown to occur throughout the day) with haemolysis during night - thrombosis e.g. Budd-Chiari syndrome - aplastic anaemia may develop in some patients - Haemolysis in ↑ complement: infections, surgery, blood transfusion, strenuous exercise, XS alcohol.
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Diagnosis and management of paroxysmal nocturnal haemoglobinuria
Diagnosis: - normal RBC morphology - Occasional poikilocytosis + anisocytosis - Normochromic - Normal/↓: hb, reticulocytes - ↑BR, LDH, ↓haptoglobin - flow cytometry of blood to detect low levels of CD59 and CD55 has now replaced Ham's test as the gold standard investigation in PNH - Ham's test: acid-induced haemolysis (normal red cells would not) Management: - blood product replacement - anticoagulation - eculizumab, a monoclonal antibody directed against terminal protein C5, is currently being trialled and is showing promise in reducing intravascular haemolysis - stem cell transplantation
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What is pyruvate kinase deficiency?
Chronic premature haemolysis, hyperreactive erythropoiesis AR mutation of PK-LR Haemolysis primarily extravascular, IV variable Block in glycolysis, accumulation of 2,3-BPG shifts oxyhaemoglobin dissociation curve to right improved O2 delivery to tissues > better tolerance of haemolytic anaemia. ATP def ``` ↓RBC ↑reticulocytes, serum glycolytic 2,3-BPG Haemoglobinuria, hemosiderinuria ↓PK enzymatic activity, PK-LR gene mutation ↑BR, LDH, ↓haptoglobin Burr cells: echinocytes ``` Splenectomy Allogeneic haematopoietic cell transplantation Chelation therapy: ↓iron related organ damage. Phototherapy Exchange transfusion
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What is sickle cell anaemia?
is an autosomal recessive condition that results for synthesis of an abnormal haemoglobin chain termed HbS It is more common in people of African descent as the heterozygous condition offers some protection against malaria Around 10% of UK Afro-Caribbean's are carriers of HbS (i.e. heterozygous). Such people are only symptomatic if severely hypoxic haemoglobin normal haemoglobin: HbAA sickle cell trait: HbAS homozygous sickle cell disease: HbSS. Some patients inherit one HbS and another abnormal haemoglobin (HbC) resulting in a milder form of sickle cell disease (HbSC) RBCs containing HbS polymerise, deform into sickle/ crescent shaped forms when deoxygenated. Sickle cells less deformable, ↓lifespan due to haemolysis, can obstruct small vessels
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Features of sickle cell anaemia?
Symptoms in homozygotes don't tend to develop until 4-6 months when the abnormal HbSS molecules take over from fetal haemoglobin. Mild to mod anaemia, stable Hb of 60-80, but acute falls due to splenic sequestration Persistent pain in chest/ skeleton gallstones Dactylitis: swollen dorsa of hands + foot FTT Jaundice Tachycardia Renal papillary necrosis Thrombotic crisis Sequestration crisis: sickling within organs such as spleen or lungs, pooling of blood with worsening anaemia. ↑reticulocytes Aplastic crisis: sudden ↓in Hb ↓reticulocytes, parvovirus Haemolytic crisis: ↓Hb ↑reticulocytes Acute chest syndrome: infection, fat from necrotic marrow or acute sequestration. Vicious cycle > block vessels, preventing other RBCs becoming oxygenated > hypoxic vasoconstriction > harder to further oxygenate blood. SOB, CP, pul infiltrates, hypoxia > death within hrs.
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Investigations of sickle cell anaemia?
definitive diagnosis of sickle cell disease is by haemoglobin electrophoresis ↓Hb, haematocrit, RBCC ↑reticulocytes, WBCC Target cells Normochromic normocytic Howell Jolly bodies: hyposplenia, purple, perph in RBC. ↑UBR, LDH, ↓haptoglobin Hb electrophoresis: fetal Hb predominante in new borns, older infants ↑HbS. DNA based assays Cellulose acetate electrophoresis: sickle cell anaemia 75-95% HbS, HbA absent, sickle cell trait 40% HbS, <2% HbF, 60% HbA. Hb solubility testing Peripheral blood smear: nucleated RBCs, sickle shaped cells
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Complications of sickle cell disease?
Anaemia: aplastic crisis Stroke, TIA, seizures Pain: vaso-oclusion, tissue ischaemia infarction, dactylitis (acute pain in small bones of hands/feet esp kids) ↑risk of infection: due to hyposplenism from multiple eps of splenic sequestration + ↓perfusion. MI, dysrhythmias, HF, cardiomeg, VTE leg uclers, sudden death Priapism, ED, preg complications eg IUGR, fetal death, LBW, preeclampsia Osteoporosis, bone infarction, AVN of bone, expansion of medullary cavity, enlarged cheeks, hair on end of bone Prolif retinopathy, retinal detachment
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Management of sickle cell anaemia?
Prophylaxis of infection, with penicillin, influenza/ pneumonia vaccines (every 5 yrs), stay hydrated, don’t get too cold, don’t drink alcohol, don’t smoke. Crisis: O2 (↓sickling), fluids, analgesia, blood transfusion, Abx if infection. Hydroxyurea: hydroxycarbamide decrease cell deformability, decrease RBC endothelial adhesion, ^HbF levels, ↓sickling. L-glutamine:↓ sickling Crizanlizumab Voxelotor
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What is macrocytic anaemia?
divided into causes associated with a megaloblastic bone marrow and those with a normoblastic bone marrow ``` megaloblastic causes: vitamin B12 deficiency folate deficiency (causes - atrophic gastritis (2' to H. Pylori), gastrectomy, phenytoin, methotrexate, pregnancy, alcohol excess) ``` ``` normoblastic causes: alcohol liver disease hypothyroidism pregnancy reticulocytosis myelodysplasia drugs: cytotoxics ```
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Features of microcytic anaemia?
``` Fatigue, dyspnoea Weight loss, pallor Impaired conc/memory Diarrhoea Oncychoschizia (brittle nails) Anaemia Sx ↑Haemolysis: jaundice, splenomegaly, lemon tinge Neuronal demyelination: numbness, tingling, subacute combined degen of SC (progressive weakness, ataxia + paraesthesia), memory loss, poor concentration, depression, irritability Glossitis > sore tongue + mouth ``` ↑risk of gastric Ca Neural tube defects
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Investigations of microcytic anaemia?
Megaloblastic: erythroblasts within BM, large, immature nucleus ↑nuclear: cytoplasmic ratio as can’t mature. ↑MCV, MCH Normal MCHC Hypersegmented neutrophils, 6+ lobes in nucleus. Poikilocytosis Macroovalcoytes (large oval cells/ macrophages) ↓reticulocyte count, Hb + haematocrit Pernicious anaemia: anti IF antibody, antigastric parietal cell.
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Management of megaloblastic anaemia?
B12: 3 injections per wk, for 2 wks, followed by 3 monthly injections Must replace B12 before folate to avoid precipitating subacute combined degen of cord 5mg folic acid daily for 4 months
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Summary of pernicious anaemia?
autoimmune disorder affecting the gastric mucosa that results in vitamin B12 deficiency antibodies to intrinsic factor +/- gastric parietal cells intrinsic factor antibodies → bind to intrinsic factor blocking the vitamin B12 binding site gastric parietal cell antibodies → reduced acid production and atrophic gastritis. Reduced intrinsic factor production → reduced vitamin B12 absorption vitamin B12 is important in both the production of blood cells and the myelination of nerves → megaloblastic anaemia and neuropathy more common in females (F:M = 1.6:1) and typically develops in middle to old age associated with other autoimmune disorders: thyroid disease, type 1 diabetes mellitus, Addison's, rheumatoid and vitiligo more common if blood group A other features: - mild jaundice - combined with pallor - 'yellow tinge' - glossitis - sore tongue Ix - microcytic anaemia, hypersegmented polymorphs on blood film, low WCC and platelets, vit B12 and folate levels, anti intrinsic factor antibodies, anti gastric parental cell antibodies ^ risk of gastric ca Tx - vit B12 replacement IM, folic acid supplementation
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Summary of diamond blackfan anaemia?
an inherited blood disorder that affects the ability of the bone marrow to produce red blood cells. In some cases there is also short stature Inheritance is typically autosomal dominant , but can rarely be X-linked AD ribosomopathy, BM failure/ aplasia, impaired haematopoiesis, macrocytic normochromic. Anaemia often at birth LBW, growth restriction Craniofacial: low set ears, micrognathia, high arched/ cleft palate, broad nasal bridge. Short webbed neck Ophthalmological: congen glaucoma, cataracts, strabismus Thumbs: duplex/bifid, flat thenar eminence Absent/ horseshoe kidney VSD/ASD, coarctation of aorta Predisposition to: leukaemia, myelodysplastic syndrome, solid tumours. Usually diagnosed within 1 mnth of life Renal imaging/ echo ↓RBCC, hb, haematocrit, reticulocytes ↑MCV, MCH, WBC, plt Bone marrow aspirate normal, except few/no erythroid precursors ↑EPO, fetal Hb due to stress haematopoiesis ↑eADA ``` 25% spont remission Allogenic haematopoietic stem cell transplant Monitor for malig development Transfusions Steroids ```
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Summary of Fanconi anaemia?
Autosomal recessive/X linked Macrocytic normochromic anaemia Aplastic anaemia ``` Features - haematological: aplastic anaemia increased risk of acute myeloid leukaemia - neurological - skeletal abnormalities: short stature thumb/radius abnormalities - cafe au lait spots ``` Usually diagnosed within 1st 8 yrs of life. Androgen therapy: oxymetholone. SC transplant GF: G-CSF, GM-CSF, thrombopoietin mimetics eg romiplostim Plt transfusion if <10,000, severe bleeding/ bruising Leukoreduced irradiated RBCs
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What is disseminated intravascular coagulation?
a serious disorder in which the proteins that control blood clotting become overactive. In DIC, the processes of coagulation and fibrinolysis are dysregulated, and the result is widespread clotting with resultant bleeding. Regardless of the triggering event of DIC, once initiated, the pathophysiology of DIC is similar in all conditions. One critical mediator of DIC is the release of a transmembrane glycoprotein (tissue factor =TF). TF is present on the surface of many cell types (including endothelial cells, macrophages, and monocytes) and is not normally in contact with the general circulation, but is exposed to the circulation after vascular damage. Upon activation, TF binds with coagulation factors that then triggers the extrinsic pathway (via Factor VII) which subsequently triggers the intrinsic pathway (XII to XI to IX) of coagulation
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Causes of disseminated intravascular coagulation?
sepsis trauma obstetric complications e.g. aminiotic fluid embolism or hemolysis, elevated liver function tests, and low platelets (HELLP syndrome) malignancy
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Typical blood picture of DIC?
``` ↓ platelets ↓ fibrinogen ↑ PT & APTT ↑ fibrinogen degradation products schistocytes due to microangiopathic haemolytic anaemia ``` (low P+F, high PT, APTT, and FDP) PT - extrinsic pathway aPPT - intrinsic pathway
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Features of DIC?
Acute: bleeding, ecchymoses, petechiae, purpura, blood oozing from gingival/ oral mucosa, sites of trauma, catheters, IV lines. Haematuria. Chronic: thromboembolism, tissue hypoxia, infarction
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Complications of DIC?
Widespread thrombosis, ischaemia, necrosis of brain, heart, kidneys, liver, lungs, adrenals, spleen > organ dysfunction ARDS PE Waterhouse Frederiksen syndrome Microangiopathic haemolytic anaemia Life threatening bleeding
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Management of DIC?
O2 IV fluids Replace clotting factors, FFP, cryoprecipitate, fibrinogen Plt transfusion <30,000
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What is haemophilia
an X-linked recessive disorder of coagulation. Up to 30% of patients have no family history of the condition. Haemophilia A is due to a deficiency of factor VIII. X linked recessive Haemophilia B (Christmas disease) there is a lack of factor IX, X-linked
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Features of haemophilia?
Asymptomatic/ spont bleeding Fatigue: iron def anaemia if sig bleeding Pallor, ↑HR, RR, ↓BP. haemoarthroses haematomas prolonged bleeding after surgery or trauma haematuria menorrhagia
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Ix of haemophilia?
prolonged APTT (as only intrinsic pathway affected) bleeding time, thrombin time, prothrombin time normal normal plt count XR - acute joint bleeding, or bone changes of chronic arthropathy CT/MRI - bleeding
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Management of haemophilia?
Up to 10-15% of patients with haemophilia A develop antibodies to factor VIII treatment. F8 infusions 2X daily 12hr ½ life. If severe. Can be frozen + administered at home. Avoid sports, trauma, meds that promote bleeding. Mild haem A: desmopressin, stimulates vWF release, promotes stabilisation of residual F8. Antifibrinolytic: aminocaproic/ tranexamic acid
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RFs for haemophilia?
peritoneal dialysis, genetics, FH, M>F, F carriers only way can occur in F is if 1X Chr, Turner’s
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What is Von Willebrand's disease?
the most common inherited bleeding disorder. The majority of cases are inherited in an autosomal dominant fashion* and characteristically behaves like a platelet disorder i.e. epistaxis and menorrhagia are common whilst haemoarthroses and muscle haematomas are rare Role of von Willebrand factor - large glycoprotein which forms massive multimers up to 1,000,000 Da in size - promotes platelet adhesion to damaged endothelium - carrier molecule for factor VIII Types - type 1: partial reduction in vWF (80% of patients), most common, AD, quatitative def - type 2*: abnormal form of vWF, qualitative - type 3**: total lack of vWF (autosomal recessive)
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Investigation for Von Willebrand's disease?
prolonged bleeding time APTT may be prolonged factor VIII levels may be moderately reduced PTT prolonged, PT normal, prolonged bleeding time. Abnormal PFA-100 ↓F8 + vWF defective platelet aggregation with ristocetin
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Management of Von Willebrand's disease?
tranexamic acid for mild bleeding desmopressin (DDAVP): raises levels of vWF by inducing release of vWF from Weibel-Palade bodies in endothelial cells factor VIII/vWF concentrate - after major injury, during operation Plt transfusion
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RF for Von Willebrands disease?
FH, consanguineous relationship, lymphoprolif disorders, AS, myeloprolif disorders, hypothyroid
125
Features of Von Willebrands disease?
Typically asymptomatic Surgery/ trauma provoke clinical manifestation Spont mucosal, cutaneous bleeding (epistaxis, easy bruising, bleeding from wounds, bleeding gums) Menorrhagia, PPH GI bleed Internal/ joint bleeding Haemarthrosis
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What is immune thrombocytopenia?
Immune (or idiopathic) thrombocytopenic purpura (ITP) is an immune-mediated reduction in the platelet count. Antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex Children with ITP usually have an acute thrombocytopenia that may follow infection or vaccination. In contract, adults tend to have a more chronic condition.
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Presentation of ITP
may be detected incidentally following routine bloods symptomatic patients may present with - petichae, purpura - bleeding (e.g. epistaxis) - catastrophic bleeding (e.g. intracranial) is not a common presentation
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Management of ITP
first-line treatment for ITP is oral prednisolone pooled normal human immunoglobulin (IVIG) may also be used - it raises the platelet count quicker than steroids, therefore may be used if active bleeding or an urgent invasive procedure is required splenectomy is now less commonly used Mycophenolate, thrombopoietin receptor agonist, rituximab, fostamatinib. Children: - usually, no treatment is required - ITP resolves in around 80% of children with 6 months, with or without treatment - advice to avoid activities that may result in trauma (e.g. team sports) - other options may be indicated if the platelet count is very low (e.g. < 10 * 109/L) or there is significant bleeding. Options include: - oral/IV corticosteroid - IV immunoglobulins - platelet transfusions can be used in an emergency (e.g. active bleeding) but are only a temporary measure as they are soon destroyed by the circulating antibodies
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What is Evan's syndrome?
ITP in association with autoimmune haemolytic anaemia (AIHA)
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Investigations of ITP
Adults: plt auto-Ig, thrombocytopenia, diagnosis of exclusion. ↓Plt. Normal: Hb, LDH, BR, haptoglobin, reticulocytes, schistocytes. Children: full blood count - should demonstrate an isolated thrombocytopenia blood film bone marrow examinations is only required if there are atypical features e.g. - lymph node enlargement/splenomegaly, high/low white cells - failure to resolve/respond to treatment
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Causes of ITP?
Kids: viral infection VZV, measles, glandular fever, vaccination. More common Adult: AI disease, after infection eg HIV Evan’s syndrome: ITP in association with AI haemolytic anaemia. Drugs: quinidine, phenytoin, valproic acid, rifampin, trimeth, sulfonamide.
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Features of ITP?
Kids: acute onset, 2-6y/o, mucocutaneous bleeding, spont nose bleeds, bleed after a cut, petechial/purpuric rash. Life threatening haem rare normally only in response to trauma. Often resolves spont over 1-2 wks, chronic if >1 yr. Adult: less acute, young-middle aged women. Major haem rarely seen, easy bruising, purpura, epistaxis, menorrhagia. RR course.
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What is heparin induced thrombocytopenia?
occurs when heparin dependent IgG antibodies bind to heparin/platelet factor 4 complexes to activate platelets and produce a hypercoagulable state. a prothrombotic disorder caused by antibodies to complexes of platelet factor 4 (PF4) and heparin
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RFs for heparin induced thrombocytopenia?
RF: unfractionated > LMWH, F>M Heparin: activates antithrombin 3, complex that inhibits thrombin, 10, 9, 12. LMWH: activates antithrombin 3, forms complex that inhibits factor 10.
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Features of heparin induced thrombocytopenia?
Usually not sufficient enough to cause sig bleeding. Skin necrosis at injection site Acute systemic reaction after IV heparin bolus: fever with chills, ↑HR, BP, RR. Limb ischaemia, organ infarction.
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Complications of heparin induced thrombocytopenia?
VTE Occlusion of LL arteries by plt rich white clots > limb ischaemia, necrosis, gangrene, loss of limbs Skin necrosis Organ infarction: kidney, MI cerebrovasculat Adrenal haem Heparin induced anaphylactoid
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Ix for heparin induced thrombocytopenia?
HIT immunoassay: ELISA for anti-PF4. Colorimetric change > optical density, HIT antibody conc, ↑OD = ↑ antibody titre Functional assay: serotonin release assay > serotonin release from plts. Ability of HIT Ig to activate test plts. Heparin induced plt aggregation assay 4Ts: thrombocytopaenia ↓plt, timing, fall in plts 5-10 days after heparin, thrombosis, no oTher explanation. Schistocytes. Normal: Hb, LDH, BR, haptoglobin, reticulocytes, schistocytes
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Tx for heparin induced thrombocytopenia?
Immediate discontinuation of heparin Non-heparin coag eg fondaparinux, argatroban, danaparoid Transition to warfarin Thormboembolectomy Heparin overdose: protamine sulphate
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What is thrombotic thrombocytopenic purpura?
Def ADAMTS13 protease > can’t break down vWF > XS accumulation > ↑ propensity for plts to attach/ accumulate > plt rich thrombi Consumptive thrombocytopenia Overlap with HUS
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RF for thrombotic thrombocytopenic purpura?
F, African, SLE, sepsis, liver disease, pancreatitis cardiac surgery ↓ADAMTS13 pregnancy (↓ADAMTS13, ↑vWF 2nd -3rd trim). Post infection, ciclosporin, oral contraceptive pill, penicillin, acyclovir, clopidogrel, tumours, SLE, HIV.
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Features of thrombotic thrombocytopenic purpura?
Pentad: thrombocytopenia, MAHA, renal dysfunction, neurologic impairment, fever Rare - typically adult females Mucocut bleeding: petechiae, purpura, epistaxis, gingival bleeding IV haemolysis: dark urine Light headed, abdo pain, easy bruising N/V Fluctuation neuro signs > microemboli
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Complications of thrombotic thrombocytopenic purpura?
Tissue ischaemia Organ dysfunction Microangiopathic haemolytic anaemia Renal insuff Focal neurological/ mental status anomalies Arrhythmias Overlaps with HUS
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Ix of thrombotic thrombocytopenic purpura?
``` MAHA: schistocytes ↓plt, hb, haematocrit ↑reticulocyte Spherocytes ↑LDH, BR, ↓haptoglobin ↑Cr ADAMTS13 assay: measures degradation of vWF by ADAMTS13 ```
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Management of TTP?
GC Plasma exchange: source of ADAMTS-13, remove auto-Ig.
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Causes of TTP?
post-infection e.g. urinary, gastrointestinal pregnancy drugs: ciclosporin, oral contraceptive pill, penicillin, clopidogrel, aciclovir tumours SLE HIV
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What is polycythaemia vera?
a myeloproliferative disorder caused by clonal proliferation of a marrow stem cell leading to an increase in red cell volume, often accompanied by overproduction of neutrophils and platelets. It has recently been established that a mutation in JAK2 is present in approximately 95% of patients with polycythaemia vera and this has resulted in significant changes to the diagnostic criteria. The incidence of polycythaemia vera peaks in the sixth decade ↑RBCs independent of EPO. ↑blood viscosity Abnormal blood flow, defective plt function > vein thrombosis, infarcts bleeding.
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Features of polycythaemia vera?
hyperviscosity pruritus, typically after a hot bath (due to ^ basophils, causing histamine release) splenomegaly haemorrhage (secondary to abnormal platelet function) - Bleeding gums, epistaxis, GI bleed, ecchymosis plethoric appearance hypertension in a third of patients Erythromelalgia: hyperaemic + inflamed extremities due to microvascular exclusion low ESR facial redness angina, intermittent claudication
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Ix for polycythaemia vera?
Excl 2° polycythaemia: ↑EPO full blood count/film (raised RBC, haematocrit; Hb, neutrophils, basophils, platelets, LDH, uric acid, raised in half of patients) JAK2 mutation serum ferritin renal and liver function tests If the JAK2 mutation is negative and there is no obvious secondary causes the BCSH suggest the following tests: - red cell mass - arterial oxygen saturation - abdominal ultrasound - serum erythropoietin level - bone marrow aspirate and trephine - cytogenetic analysis - erythroid burst-forming unit (BFU-E) culture Also low ESR and raised leukocyte alkaline phosphatase ↓EPO, ESR Bone marrow aspiration: hypercellularity with trilineage growth (panmyelosis), erythroid, granulocytic + megakaryocytic prolif with pleomorphic, mature megakaryocytes. JAK 2 mutation ↓MCV, ferritin, Fe def. ↑leukocyte ALP
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Management of polycythaemia vera?
aspirin - reduces the risk of thrombotic events venesection - first-line treatment to keep the haemoglobin in the normal range chemotherapy - decrease RBC production - hydroxyurea - slight increased risk of secondary leukaemia - phosphorus-32 therapy IFNα: ↑RBC destruction, peginterferon α 2a.
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Prognosis of polycythaemia vera?
thrombotic events are a significant cause of morbidity and mortality 5-15% of patients progress to myelofibrosis 5-15% of patients progress to acute leukaemia (risk increased with chemotherapy treatment)
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Causes of polycythaemia vera?
Reactive: dehydration + stress. 1°: XS prolif of progenitor cells, XS RBC often neutrophilia + plts. JAK2 mutation. EPO receptor mutation 2°: inappropriate activation of erythropoiesis > high altitude, smoking, chronic lung disease, CVD, OSA, renal disease, HCC, adrenal tumours, cerebellar haemangioma, hypernephroma, uterine fibroids.
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Complications of polycythaemia vera?
Abnormal blood flow Hyperuricaemia: ↑cell turnover. Gout Spent phase: myelofibrosis (>AML), extramedul haematopoiesis in liver, spleen. HTN Budd-Chiari, DVT MI Stroke
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What is essential thrombocytosis?
Thrombocytosis is an abnormally high platelet count, usually > 400 * 109/l. Overproduction of megakaryocytes in BM ↑Plt, abnormally shaped ↓Plt survival. JAK2, MPL, calreticulin Cause: reactive (acute phase protein), malig, part of myeloprolif disorder > PV, hyposplenism, CML, myelofibrosis
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Features of essential thrombocytosis?
platelet count > 600 * 109/l asymptomatic both thrombosis (venous or arterial) and haemorrhage can be seen a characteristic symptom is a burning sensation in the hands Thrombosis: ischaemia, stroke, erythromelalgia Headache, dizziness, fatigue, vision loss, abdo pain, nausea Paradoxical bleed: epistaxis, bleeding gums, ecchymoses Splenomegaly a JAK2 mutation is found in around 50% of patients
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Management of essential thrombocytosis?
high risk: - hydroxyurea (hydroxycarbamide) is widely used to reduce the platelet count - interferon-α is also used in younger patients low-dose aspirin may be used to reduce the thrombotic risk if low risk severe - plt pheresis, removal of plts from blood d
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Ix for essential thrombocytosis?
↑Plt, anisocytosis (RBC unequal size) ↑bleeding time BM aspiration: normal cellularity Hx of thrombosis, bleeding, vasomotor Sx, 1st trimester fetal loss
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What is myelodysplastic syndrome?
Abnormal ineffective haematopoiesis > peripheral cytopenia BM failure of all myeloid lines, blast accumulation <20% Idiopathic Toxins, IS agents, chemo, radiation Genetic >70y/o acquired neoplastic disorder of hematopoietic stem cells pre-leukaemia, may progress to AML more common with age presents with bone marrow failure (anaemia, neutropaenia, thrombocytopenia)
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Features of myelodysplastic syndrome?
Anaemia Neutropenia Thrombocytopaenia Pre-leukaemia
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Complications of myelodysplastic syndrome?
AML/CML Most succumb to bleeding/ infections before AML
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Ix of myelodysplastic syndrome?
``` ↓RBC, WBC, pLT Normal/ ↑MCV, ↑RDW ↓reticulocytes ↑blasts Bilobed neutrophils, ring sideroblasts, megaloblastoid maturation, nuclear budding abnormalities, pawn ball megakaryocytes ```
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Tx of myelodysplastic syndrome?
TNF inhibs: lenalidomide, thalidomide Allogenic haematopoietic stem cell transplant
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What is myelofibrosis?
- a myeloproliferative disorder - thought to be caused by hyperplasia of abnormal megakaryocytes - the resultant release of platelet derived growth factor is thought to stimulate fibroblasts - haematopoiesis develops in the liver and spleen - ↓all cell types - JAK2, MPL, calreticulin - Late in course of PV/ET
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Features of myelofibrosis?
e.g. elderly person with symptoms of anaemia e.g. fatigue (the most common presenting symptom) massive splenomegaly hypermetabolic symptoms: weight loss, night sweats etc Asymptomatic Thrombosis, ischaemia Headache, dizziness, fatigue Numbness in extremities Erythromelalgia Vision loss, abdo pain, nausea Bleeding: epistaxis, bleeding gums, bruises Splenomegaly VTE due to initial XS plt Anaemia Susceptibility to infection
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Ix of myelofibrosis?
anaemia and low plts high WBC and platelet count early in the disease progress to pancytopenia 'tear-drop' poikilocytes on blood film unobtainable bone marrow biopsy - 'dry tap' therefore trephine biopsy needed Biopsy - hypocellularity, fibrosis high urate and LDH (reflect increased cell turnover)
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What is anti phospholipid syndrome?
Antiphospholipid syndrome is an acquired disorder characterised by a predisposition to both venous and arterial thromboses, recurrent fetal loss and thrombocytopenia. It may occur as a primary disorder or secondary to other conditions, most commonly systemic lupus erythematosus (SLE) A key point for the exam is to appreciate that antiphospholipid syndrome causes a paradoxical rise in the APTT
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Features of anti phospholipid syndrome?
``` venous/arterial thrombosis recurrent fetal loss livedo reticularis thrombocytopenia prolonged APTT other features: pre-eclampsia, pulmonary hypertension ``` Associations other than SLE other autoimmune disorders lymphoproliferative disorders phenothiazines (rare)
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Management of anti phospholipid syndrome?
primary thromboprophylaxis - low-dose aspirin secondary thromboprophylaxis - initial venous thromboembolic events: lifelong warfarin with a target INR of 2-3 - recurrent venous thromboembolic events: lifelong warfarin; if occurred whilst taking warfarin then consider adding low-dose aspirin, increase target INR to 3-4 - arterial thrombosis should be treated with lifelong warfarin with target INR 2-3
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Ix of anti phospholipid syndrome?
>1 AP Ig. Lupus anticoag AKA lupus Ig, anticardiolipin Ig, anti-β2 glycoprotein I, antiphospholipid Ig Prolonged PT, PTT False pos in veneral disease lab for syphilis Thrombocytopenia Pos coombs test
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Summary of antithrombin 3 deficiency?
AT3 normally inactivates thrombin, factor 5 AD mutation Liver disease, warfarin, nephrotic syndrome, renal failure, depletion in acute thrombosis/ DIC Features - DVT/PE Complications - VTE heparin resistance Ix - ↓antithrombin 3 activity No ↑ in aPTT following heparin Tx - Anticoag
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Summary of Factor 5 Leiden?
Most common inherited thrombophilia Activated protein C resistance Mutant coag factor 5, lacks Arg506 cleavage site > resitant to degradation by activated protein C > unreg activation of coag cascage > hypercoag state > VTE Protein C resistance RF: pregnancy, oral hormonal contraceptives Ix - ↓antithrombin 3 activity No ↑ in aPTT following heparin Heterozygotes have a 4-5 fold risk of venous thrombosis. Homozygotes have a 10 fold risk of venous thrombosis but the prevalence is much lower at 0.05% VTE DVT Possible fetal loss >2 thrombolic events > life long anticoag
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Summary of protein C deficiency?
Unreg activation of coag cascade Protein C usually vit K dependent inhibitor of factors 5 + 8 AD inherited Causes: acute thrombois, DIC, liver disease, warfarin. ``` Sx: VTE Homozygotes: neonatal purpura fulminans T1: ↓levels T2: normal levels, ↓ function ``` Complications Warfarin induced thrombotic skin necrosis Ix: ↓protein C Tx: - Prophylactic protein C concentrate - Anticoags - Warfarin induced skin necrosis: stop warfarin, start vit K, heparin, protein C/ FFP
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Summary of protein S deficiency?
Cofactor of protein C ↓protein C activity > enhanced coag cascade AD PROS1 mutation Causes: pregnancy, oral hormonal contraceptive DIC, acute thrombosis, HIV, nephrotic syndrome, liver disease Sx: VTE Homozygotes: neonatal purpura fulminans. T1: ↓protein S T2: ↓function T3: ↓free protein S + function, normal total protein S. Ix: Protein S assay Tx: Prophylactic anticoag in high risk situations eg post partum, preop
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Summary of hereditary angioedema?
AD, ↓plasma C1 inhibitor, uncontrolled release of bradykinin > oedema Sx: attacks may be proceeded by painful macular rash painless, non-pruritic swelling of subcutaneous/submucosal tissues may affect upper airways, skin or abdominal organs (can occasionally present as abdominal pain due to visceral oedema) urticaria is not usually a feature Ix: C1-INH level is low during an attack low C2 and C4 levels are seen, even between attacks. Serum C4 is the most reliable and widely used screening tool Tx acute - HAE does not respond to adrenaline, antihistamines, or glucocorticoids - IV C1-inhibitor concentrate, fresh frozen plasma (FFP) if this is not available prophylaxis: anabolic steroid Danazol may help
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Summary of acute intermittent porphyria
AD, defect in porphobilinogen deaminase Toxic accumulatio of delta aminolaevulinic acid + porphobilinogen ``` Sx: Abdo pain, vomiting Neuropsychiatric Sx Motor neuropathy Depression HTN tachycardia 20-40 y/o F ``` Ix: Urine turns deep red on standing ↑urinary porphobilinogen (more between attacks than acute attacks) Assay of red cells for porphobilinogen deaminase ↑delta aminolaevulinic acid + porphobilinogen Tx: Avoid triggers Acute attacks: IV haematin/ haem arginate. IV glucose
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What are packed red cells + when to use?
chronic anaemia, centrifuging of whole blood. Each unit 250-350 mls, ↑Hb by 10. Stat in emergency, usually 90-120 mins or 2-3hrs if comorbidities Irradiated products (depleted of T lymphocytes) for graft vs host disease Washes Red cell concentrates prevent anaphylaxis
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What is plt rich plasma + when to use?
bleeding in thrombocytopenia, prophylactically in marrow failure. Obtained by low speed centrifugation Plt transfusions have highest risk of bacterial contamination <10X109 if no active bleeding Plt don’t have to be ABO compatible.
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What is prothrombin complex concentrate + when to use?
reversal of anticoag in pts with severe bleeding or head injury. F2, 7, 9, 10 – 1972.
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What is FFP + when to use?
from single unit of blood, contains clotting factors, albumin + immunuglobulin. Correct clotting def, pts with hepatic failure who are to undergo surgery Pt or PTT >1.5
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What is cryoprecipitate + when to use?
formed from FFP, contains F8, fibrinogen. C vWF. Useful in DIC, liver failure, major haem. 15-30mL
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Threshold and target for RBC?
RBC transfusion threshold: <70g/L or <80g/L in ACS RBC target: 70-90 or 80-100 in ACS. RBC stored at 4°C In non urgent scenario: unit of RBC transfused over 90-120 mins.
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Threshold and target for plt's?
Plt transfusion < 30X109 sig bleeding | Plt transfusion <100X109 for severe bleeding or bleeding at critical sites eg CNS
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Summary of non haemolytic febrile transfusion reaction
Ig reacting with white cell fragments in blood product + cytokines that have leaked from blood during storage Fever + chills More common in plt transfusion Slow or stop transfusion Paracetamol Monitor
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Summary of minor allergic reaction > transfusion
Caused by foreign plasma proteins Pruritis Urticaria Temp stop transfusion Antihistamine Monitor
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Summary of Anaphylaxis in blood transfusion
Pts with IgA def who have anti IgA Ig Mins after starting Hypotension Dyspnoea, wheeze, stridor Angioedema Stop transfusion IM adrenaline O2 fluids
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Summary of acute haemolytic reaction
ABO incompatible blood massive haemolysis RBC destruction by IgM Begin few minutes after transfusion is started Fever Abdo pain Hypotension, agitation Mins after transfusion started DIC Renal failure Send blood for direct coombs test Repeat typing + cross match Stop transfusion Fluid resus
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Summary of transfusion associated circ overload
Causes: Rate of transfusion Pre-existing HF Pul oedema HTN Acute/worsening oedema within 6hrs of transfusion Tx: Slow or stop transfusion Furosemide O2
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Summary of transfusion related acute lung injury
Non cardiogenic pul oedema, ↑vascular permeability caused by host neutrophils that become activated by substances in donated blood Within 6 hours of transfusion ``` Hypoxia Pul infiltrates on CXR Fever Hypotension Within 6 hrs of transfusion ``` ARDS Stop transfusion O2 Supportive care
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Summary of post transfusion purpura?
Rare | 7-10 days post transfusion containing plt