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Flashcards in Pathology - hem/onc Deck (72)
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1
Q

Acanthocyte

A

liver disease, abetalipoproteinemia

cholesterol dysregulation

2
Q

Basophilic stippling

A

Lead poisoning

3
Q

Degmacyte

A

G6PD deficiency

4
Q

Elliptocyte

A

Hereditary elliptocytosis

5
Q

Macro-ovalocyte

A

Megaloblastic anemia

6
Q

Ringed sideroblast

A

excess iron in mitochondria

7
Q

Schistocyte

A

DIC, TTP, HUS, HELLP

8
Q

Sickle cell

A

Sickle cell

dehydration, deoxygenation, high altitude

9
Q

Spherocyte

A

hereditary spherocytosis (incr. MCHC!)

10
Q

Dacrocyte (teardrop cell)

A

Bone marrow infiltration (RBC squeezed out)

11
Q

Target cell

A

HbC disease, Asplenia, Liver disease, Thalassemia

12
Q

Heinz bodies

A

Oxidation of Hb-SH with subsequent phagocytic damage to RBC membrane (leads to bite cells)

G6PD deficiency

13
Q

Howell-Jolly bodies

A

basophilic nuclear remnants found in RBCs

(normally removed by splenic macrophages)

sign of asplenia or functional asplenia (sickle-cell, polysplenia)

14
Q

Microcytic, hypochromic anemias (5 total)

A
Iron deficiency
Alpha-thalassemia
Beta-thalessemia
Lead poisoning
Sideroblastic anemia
15
Q

Lab tests in iron-deficiency anemia

A

decr. iron, incr. TIBC, decr. ferritin

look for conjunctival pallor and spool nails (koilonychia)

16
Q

Gene deletions found in alpha-thalassemia

A

loss of alpha-globin gene

cis deletion = Asians
trans deletion = African

4 alleles deleted = incompatible with life
3 alleles deleted = very little alpha globin, HbH disease

17
Q

Gene mutations found in beta-thalassemia

A

Point mutations in splice sites and promoter sequences

Minor: asymp. look for incr. HbA2

Major:

  • symp after 6mos of age, req. blood transfusions
  • marrow expansion –> bone deformities
  • extramedullary hematopoiesis, incr. risk of parvob19 induced crisis
18
Q

Lab/smear findings in lead poisoning

A

Lab: decr. heme synthesis, incr. protophorphyrin

Smear: rRNA aggregates –> basophilic stippling

19
Q

Clinical findings of LEAD poisoning

A

Lead lines on x-ray: long bones and gingivae

Encephalopathy and RBC stippling

Abdominal colic and sideroblastic anemia

Drops - wrist and foot drop. Dimercaprol and EDTA

20
Q

Causes of sideroblastic anemia

A

defect in heme synthesis

Genetic, acquired (myelodysplasia), reversible (alcohol, B6 deficiency, copper deficiency, isoniazid)

Use Prussian blue to stain iron-laden mitochondria

TX: B6/pyroxidine (provides co-factor)

21
Q

Sideroblastic anemia labs

A

incr. iron, normal to decr. TIBC, incr. ferritin

22
Q

4 causes of macrocytic anemia

A

Megaloblastic: folate deficiency, B12 deficiency, orotic aciduria

Nonmegaloblastic: unimpaired DAN synthesis (alcoholism, liver disease, hypothyroidism, reticulocytosis)

23
Q

Mechanism of megaloblastic anemia

A

Impaired DNA synthesis –> maturation of nucleus of precursor cells in bone marrow is slower than the maturation of the cytoplasm

Leads to RBC macrocytosis and hypersegmented neutrophils

24
Q

Folate vs. B12 deficiency

A

Folate = incr. homocysteine, normal MMA, no neuro sx

B12 = incr. homocysteine, incr. MMA, neuro sx “subacute combined degeneration”

25
Q

Orotic aciduria vs. OTC deficiency

A

Orotic aciduria = defect in UMP synthase, no incr. NH4

OTC deficiency = incr. orotic acid and incr. NH4

26
Q

Non-hemolytic normocytic normochromic anemia (2 total)

A

Anemia of chronic disease - incr. hepcidin, decr. iron release from macs (labs = decr. iron, decr. TIBC, incr. ferritin)

Aplastic anemia - failure or destruction of myeloid stem cells (radiation/drugs, viral agents, Fanconi anemia, idiopathic), fatty infiltration of marrow –> pancytopenia

27
Q

Characteristics of intravascular hemolytic normocytic anemia

A

decr. haptoglobin, incr. LDH, schistocytes, incr. retics

think mechanical, PNG, MAHA

28
Q

Characteristics of extravascular hemolytic normocytic anemia

A

Macs in spleen clear RBCs, so no Hgb in urine, incr. unconj bilirubin, jaundice

Ex. HS, PK deficiency, HbC defect, sickle cell anemia

29
Q

HS protein defect

A

Ankyrin, spectrin –> small round RBCs with decr. surface area

Positive osmotic fragility test (blood mixed w/ 0.36% buffered saline)

30
Q

Oxidative stress for G6PD patients

A

sulfa drugs, antimalarials, infections, fava beans

31
Q

PNH mechanism

A

complement-mediated RBC lysis

impaired GPI anchor for DAF/CD55, which normally protects RBCs (loss of CD55, CD59)

Look for Coombs (-) anemia, pancytopenia, venous thrombosis (Budd-Chiari)

32
Q

Sickle cell anemia mechanism

A

HbS point mutation (glutamic acid out, valine in on B-globin)

33
Q

Complications from sickle cell anemia

A
aplastic crisis
autosplenectomy
splenic infarct (risk of SHiN infection!)
salmonella osteomyelitis
dactylitis/acute chest
renal papillary necrosis
34
Q

Warm vs. cold autoimmune hemolytic anemia

both are Coombs positive

A

Warm (IgG) = chronic, SLE, CLL, drugs

Cold (IgM) = acute, seen in M. pneumoniae infections, Mono

35
Q

Serum iron
TIBC/transferrin
Ferritin
% transferrin saturation

A

Iron-deficiency: decr***, incr, decr, double decr.

Chronic dz: decr. decr. incr***

36
Q

Transferrin vs. ferritin

A

Transferrin: transports iron in blood
Ferritin: primary iron storage protein in the body

37
Q

Three heme synthesis defects to know

A

Lead poisoning
Acute intermittent porphyria
Porphyria cutanea tarda

38
Q

Enzymes affected in lead poisoning

A

Ferrochelatase and ALA dehydratase

accumulation of protoporphyrin, delta ALA

39
Q

Enzymes affected in AIP

A

Porphobilinogen (PBG) deaminase

Porphobilinogen, delta ALA, coporphobilinogen (urine)

Can be precipitated by alcohol, smoking, rifampin, sulfonamides

Tx: glucose (to downregulate ALA synthase)

40
Q

Enzymes in porphyria cutanea tarda

A

Uroporphyrinogen decarboxylase

Uroporphyrin (tea-colored urine)

41
Q

Iron poisoning mechanism

A

Cell death due to peroxidation of membrane lipids

42
Q

Factors tested by PT

A

Common pathway: 1, 2, 5

Extrinsic pathway: 7, 10

43
Q

Factors tested by PTT

A

Common and intrinsic pathway

All factors except 7 and 10

44
Q

Bleeding time

A

incr in BT = defect in platelet plug formation

45
Q

Platelet disorders and specific defect

A

Bernard-Soulier: decr. GpIb (decr. plt to vWF adhesion)

Glanzmann: decr. GpIIb/IIIa (decr. plt to plt aggregation)

ITP: anti-GpIIb/IIIa antibodies

46
Q

TTP mechanism

A

ADAMTS13 defect/absence –> decr. degradation of vWF multimers –> large multimers –> plt aggregation and thrombosis

Look for CNS sx, renal sx, fever, low plts, MAHA

47
Q

Defects found in vWF disease

A

intrinsic pathway defect: loss of factor 8 (incr. PT)

defect in platelet plug formation (incr. bleeding time)

dx: ristocetin cofactor assay (primes platelets for vWF binding)
tx: desmopressin (incr vWF and factor 8 release)

48
Q

Labs found in DIC

A

incr. fibrin split products, decr. fibrinogen, decr. factors 5 and 8

49
Q

Mechanisms of antithrombin deficiency

A

inherited

acquired in renal failure/nephrotic syndrome (loss of factors in urine)

50
Q

Protein C deficiency common syndrome

A

Skin and subcutaneous tissue necrosis after warfarin adminstration

51
Q

FFP vs. cryoprecipitate

A

treat DIC, cirrhosis, warfarin reversal

vs.

coagulation factor deficiencies involving VII and fibrinogen

52
Q

Leukemoid reaction vs. CML

A

Leukemoid = incr. WBC, incr. Leukocyte alkaline phosphatase

CML = incr. WBC, decr. LAP

53
Q

Hodgkin lymphoma

location in body
cells
associations

A

Localized, single group of nodes, contiguous spread

Reed-Sternberg cells

assoc. with EBV

54
Q

non-Hodgkin lymphoma

location in body
cells
associations

A

Multiple, peripheral nodes

B cells

assoc. HIV and autoimmune disease

55
Q

Non-Hodgkin B cell lymphoma translocations

Burkitt
Follicular
Mantle cell

A

Burkitt - t8:14 (c-myc, transcription activator)
Follicular - t14:18 (BCL-2, oncogene that inhibits apoptosis, indolent!)
Mantle cell - t11:14 (cyclinD1, CD5 positive)

Ch. 14 = heavy chain Ig
Diffuse large cell - no translocation but most common non-Hodgkin lymphoma in adults

56
Q

Non-Hodgkin T cell neoplasms

A

Adult T-cell lymphoma: caused by HTLV (assoc with IVDA)

Mycosis fungoides: cutaneous T-cell lymphoma

57
Q

Multiple myeloma

products
diagnosis

A

IgG or IgA
M spike on serum protein electrophoresis
Ig light chains in urine (Bence-Jones)
Rouleaux formation (stacked RBCs)

CRAB: elevated Ca, Renal involvement, Anemia, Bone lytic lesion

Complications: incr. susceptibility to infection, amyloidosis (apple-green birefringence) in heart, tongue, kidney, CNS

58
Q

TdT+, CD10+

A

ALL markers (can have pre-B cell leukemia precursor)

most responsive to therapy

young people

59
Q

CD20+, CD5+ B cell neoplasm

A

SLL/CLL

old people

60
Q

TRAP stain positive B cell neoplasm

A

Hairy cell leukemia

Marrow fibrosis (leads to dry tap on aspiration)

Tx: cladribine

61
Q

Auer rods

Responds to Vitamin A

A

AML

Auer rods = stain for peroxidase, indicate myeloid differentiation

t(15;17) responds to Vitamin A (retinoic acid receptor)

62
Q

t(9;22) translocation

A

CML, Philadelphia chromosome

63
Q

Lytic bone lesions

Recurrent otitis media w/ mass involving mastoid bone

A

Langerhaans histiocytosis

S-100 marker, CD1a

64
Q

JAK2 disorders (non-receptor tyrosine kinase assoc. w/ EPO receptor)

A

Polycythemia vera - itching after hot shower (incr. basophils)

Essential thrombocytosis - overproduction of abnormal platelets

Myelofibrosis - obliteration of bone marrow due to incr. fibroblast activity

65
Q

Hemolytic-uremic syndrome (HUS)

A

Shiga toxin –> endothelial cell injury –> isolated activation of platelets –> RBC damage as they travel through narrrow lumens

66
Q

Tumor suppressor genes

A
p53 (apoptosis inducer)
Rb (regulates G1 to S checkpoint, phosphorylated/mutated = inactive)
BRCA (DNA repair)
APC (tumor suppressor)
NF-1 (neurofibromatosis)
67
Q

Protooncogenes

A
Ras (signal transduction)
Erb-B1 (tyrosine kinase)
Erb-B2/HER2 (tyrosine kinase)
N-myc (neuroblastoma)
C-myc (Burkitt, transcription activator)
68
Q

Penetration of the basement membrane

A
  1. ) detachment of tumor cells (decr. E-cadherins)
  2. ) adhere to basement membrane (incr. laminin)
  3. ) invasion of BM (incr. metalloproteinases)
69
Q

Cytokine mediator of cachexia

A

TNF-alpha

70
Q

Factor V Leiden mechanism of pro-coagulation

A

increased coagulation (reduced susceptibility to cleavage) and decreased anticoagulation (decreased APC activity)

71
Q

Oxidative stress is induced by…

A

Bactrim, dapsone, antimalarials, nitrofurantoin

fava beans

infection

72
Q

Pure red cell aplasia (PRCA)

A

associated with thymoma, leukemia, parvovirus B19