Haematology Flashcards
(101 cards)
Describe the spectrum of symptoms a patient with anaemia might describe.
Asymptomatic Fatigue Headaches, Faintness Breathlessness Angina Intermittent Claudication Palpitations
List the causes of a microcytic anaemia
Iron Deficiency
Thalassaemia
Sideroblastic Anaemia
List the causes of a normocytic anaemia
Acute Blood Loss Anaemia of Chronic Disease CKD Marrow Infiltration, Fibrosis Myelomas Mixed Defiecieny e.g. Iron and B12
List the causes of a macrocytic anaemia
Alcohol Haemorrhage/Haemolysis (increase reticulocytes) Vit B12/Folate Deficiency Hypothyroidism Pregnancy Drug Therapy
What test should always be done in a patient presenting with normocytic anaemia?
Urine and Serum Electrophoresis - looking for paraprotein for myeloma
Anaemia of chronic disease is a diagnosis on exclusion and should only be made if everything else has been ruled out.
Describe the causes of thrombocytopenia
DECREASED PRODUCTION Haematinic Deficiency e.g. B12, Folate Acute Leukaemia/Myelodysplastic Syndromes i.e. bone marrow failure INCREASED CONSUMPTION e.g. DIC, Sepsis Immune Mediated e.g. ITP Drug Induced
Describe the causes of thrombocytosis (high platelets) and how can we distinguish between them?
Can be reactive i.e. in response to infection
Can be due to a myeloproliferative neoplasm
History and Clinical Examination
Trend of platelet count (sudden increase suggests reactive,, more gradual increased suggests MPN)
Describe what a myeloproliferative neoplasm is.
Uncontrolled clonal proliferation of one or more of the cell lines in the bone marrow.
List some examples of Myeloproliferative Neoplasms
Polycythemia Vera Essential Thrombocytopenia Myelofibrosis Chronic Myeloid Leukemia N.B. these conditions grouped together as there can be transition from one disease to another and they may also transform into AML
Describe what happens in Polycythemia Vera
Alteration in pluripotent progenitor cell
Leading to excessive proliferation of erythoid (RBCs), myeloid (basophil, neutrophil, eosinophiol, macrophage) and megakaryocytic (platelets)
What mutation is commonly associated with polycythemia vera
JAK-2 - means bone marrow is continuously signalled to produce cells with or without the presence of Epo
Describe the clinical features of polycythemia vera?
Insidious onset usually >60yrs
Tiredness, depression, vertigo, tinnitus and visual disturbance
Can also get hypertension, angina, intermittent claudication and a tendency to bleed
Severe itching after a hot bath or when patient is warm is common
Spleen in palpable in 70%, hepatomegaly 50%
Thrombosis and haemorrhage are the major complications
How to you diagnose polycythemia vera?
Increased haemoglobin
Presence of JAK2 kinase mutation (taken over from marrow biopsy)
Serum epo level below normal
How is polycythemia vera treated?
Aspirin to decrease stroke risk
Venesection weekly to decrease haematocrit
Chemo with hydroxycarbamite in some with HIGH HIGH platelets- can’t venesect platelets as made too quickly - slows down marrow function
Describe Essential Thrombocytopenia
ELEVATED PLATELET COUNT
normal WBCs and RBCs
How might be patients present with essential thrombocytopenia?
Asymptomatic incidental finding
Thrombo-embolic disease
Less commonly bleeding
Describe how you diagnose essential thrombocytopenia?
JAK-2 mutation in around 50%
If negative check for calreticulin or MPL
If these both negative - do bone marrow biopsy, will show increased megakaryocytes
How do you treat Essential Thrombocytopenia?
Aspirin to decrease stroke risk
Hydroxycarbamite
Describe Myelofibrosis
Get clonal proliferation of stem cells and myeloid metaplasia in the liver, spleen and other organs, with FIBROSIS in the bone marrow (hyperplasia of abrnomal megakaryocytes which release fibroblast stimulating factors
How does Myelofibrosis Present?
Insidiously with lethargy, weakness and weight loss
Abdominal fullness from splenomegaly
Bruising, bleeding and anaemia can occur
Severe pain related to respiration may indicate peri-splenitis secondary to splenic infarction
How is Myelofibrosis Diagnosed?
Leucoerythroblastic blood film - tear drop red cells
Anaemia, Thrombocytopenia, raised WCC
Bone marrow aspiration often unsuccessful due to nature of condition
JAK-2 mutation in 50%
What is the treatment of Myelofibrosis?
Supportive - blood transfusions, folic acid, analgesia
If spleen is painful and transfusion requirements are high a splenectomy may be performed
Tx of Disease - spectrum from observation alone - bone marrow transplant
New promising therapy with JAK inhibitors
Describe the chromosomal abnormality of CML
Philadelphia Chromosome
Long arm of chromosome 22 has been shortened by reciprocal translocation with chromosome 9
Puts the BCR:ABL genes together which causes upregulation of tyrosine kinase
Describe how patients with CML present?
Peak age 40-60 Some are asymptomatic OR Symptomatic anaemia Abdo discomfort sue to splenomegaly Weight loss, fever, sweats Headaches, visual disturbance, priapism due to leucostasis