Clinical Haematology Flashcards
What is Pancytopenia?
Condition characterised by a decrease in all three blood cell types : RBCs, WBCs, Platelets
Patients may present with symptoms related to anaemia, bleeding or infections
What are the potential causes of Pancytopenia?
- Most common underlying causes of pancytopenia are bone marrow disorders such as aplastic anaemia or myelodysplastic syndrome
- Medications, such as chemo or immunosuppressants
- Drug interaction between azathioprine and allopurinol can cause bone marrow suppression
- Nutritional deficiencies such as B12 or Folate
- Autoimmune disorders, such as SLE or RA
H&E of Pancytopenia
Symptoms of Anaemia
- Fatigue
- Weakness
- Pallor
- SOB
Symptoms of low platelets + WBCs
- Easy bruising
- Bleeding gums
- Frequent infections
Exam may reveal pallor, petechiae or purpura
Investigations for Pancytopenia
FBC is first-line and will reveal low levels of all blood cell types
Bone marrow biopsy may be necessary to determine underlying cause
Management of Pancytopenia
- Treat underlying cause
- In cases of severe pancytopenia, blood transfusions and/or bone marrow transplant may be needed
- Referral to specialist for further evaluation and management
What is Polycythaemia?
Condition where body produces too many RBCs
OR
There is a relative excess of RBCs
What are the causes of Polycythaemia?
Primary: (Polycythaemia rubra vera)
Relative causes:
- dehydration
- stress (Gaisbock syndrome)
Secondary:
- COPD
- Altitude
- Obstructive sleep apnoea
- Excessive EPO (cerebellar haemangioma, hypernephroma, hepatoma, uterine fibroids)
How can true and relative Polycythaemia be distinguished?
To differentiate between true (primary or secondary) polycythaemia and relative polycythaemia red cell mass studies are sometimes used. In true polycythaemia the total red cell mass in males > 35 ml/kg and in women > 32 ml/kg
- uterine fibroids may cause menorrhagia which in turn leads to blood loss - polycythaemia is rarely a clinical problem
What is Polycythaemia rubra vera?
- Mutation in JAK2 gene
- Too many RBCs made by bone marrow
H&E of Polycythaemia
- Itchiness (especially after warm bath)
- Burning/tingling in hands
- Blurry vision
- Headaches
- Plethoric - red nose
- Splenomegaly
- Thrombosis
- Gout
Investigations of Polycythaemia
- Examine for DVT
- FBC
- high Hb
- Hct >0.52 in males and >0.48 in females is DIAGNOSTIC
- EPO levels (low in primary and high in EPO tumour)
- CXR, Renal scan
- Bone Marrow biopsy
- Gene panel for JAK2 Mutation
Management of Polycythaemia
- First line - Venesection (maintain Hct <0.45)
- Aspirin
- Hydroxycarbamide if high risk of thrombosis
- JAK2 inhibitors
- Annual follow ups to check for signs of myelofibrosis
What is Haemophilia A?
Factor 8 deficiency
What is Haemophilia B?
Factor 9 deficiency
Genetics of Haemophilia
X-linked recessive disorder
H&E of Haemophilia
- Haemarthrosis (bleeding into joints - swollen and painful)
- Haematoma
Severe will present within 2 years and bleeding into joints
Milder cases will present later in life after surgery or trauma
Investigations for Haemophilia
Blood tests
- Prolonged APTT (factors 8 and 9 are part of the intrinsic pathway)
- Factor assay
- PT/INR and platelet count will be normal
Management of Haemophilia
- Avoid high impact sports
- Avoid blood thinning medication
- Desmopressin - release of stored factor 8 and VWF
- Recombinant factor 8/9
What is Disseminated Intravascular Coagulation?
DIC
- Widespread activation of clotting leading to clotting factors and platelets being consumed = increased risk of bleeding
- Tissue factor mediated
- Risk factors include malignancy, sepsis, trauma/surgery/burns, pregnancy complications
Investigations of DIC
Bloods
- Low platelets and fibrinogen
- Increased fibrin degradation products
- Long PT and APTT
- Schistocytes
- High D-dimer
Management of DIC
- Treat cause
- Give transfusions
- Up to 4 units of FFP and 10 units of cryoprecipitate whilst waiting for coagulation studies
