Haematology Flashcards
Microcytic anaemia causes
Low MCV <80 fl Defects in haem synthesis: - iron deficiency - anaemia of chronic disease - sideroblastic anaemia Defects in globin synthesis - thalassaemia
Iron deficiency anaemia
Blood loss: menorrhagia, upper/lower GI bleed, hookworms
Reduced absorption: coeliac disease, resections
Reduced intake: diet
Increased demands: pregnancy, growth
Sideroblastic anaemia
Abnormality of haem synthesis (iron inclusion within the cell)
Inherited or secondary (alcohol/drugs/lead poisoning)
α thalassaemia
Microcytic anaemia
2α = trait, 3α = HbH disease, 4α = Hb Barts (incompatible with life)
ß thalassaemia
2β = transfusion dependent
Desferioxamine for chelation
Hepatosplenomegaly, jaw protrusion, big forehead, “hair on end” skull XR
Management of sideroblastic anaemia
Treat the cause
Inherited: pyridoxine
Management of lead poisoning
Remove source
Dimercaprol
D-penicillinamine
Normocytic anaemia causes
MCV 80-100
Acute blood loss: peptic ulcer, varices
Failure of RBC production:
- bone marrow failure or suppression (aplastic anaemia, chemotherapy)
- bone marrow infiltration (malignancy)
- renal failure (reduced erythropoietin)
- early iron deficiency or anaemia of chronic disease
- hypothyroidism (+macrocytic)
- vitamin B2/6 deficiency
Haemolysis
Uncompensated fluid increase: pregnancy, fluid overload
Pooling of red cells in spleen: hypersplenism (portal cirrhosis)
Macrocytic anaemia
MCV >100fl Megaloblastic: vitamin B12 or folate acid deficiency Drugs (methotrexate, hydroxyurea, azathioprine, zidovudine Non-megaloblastic: Alcohol excess/liver disease (round macrocytes) Myelodysplasia Multiple myeloma Hypothyroidism Aplastic anaemia Haemolysis (reticulocytosis) Drugs Pregnancy
Blood film findings
- hypersegmented neutrophils
- schistocytes
- spherocytes
- Howell-Jolly bodies
- Heinz bodies
- dacrocytes
- codocytes
- burr cells
Hypersegmented neutrophils: megaloblastic anaemia, cytotoxic drugs, myelodysplastic syndrome
Schistocytes: MAHA, sickle cell disease
Spherocytes: hereditary spherocytosis, autoimmune haemolytic anaemia
Howell-Jolly bodies: reduced splenic function, severe haemolytic anaemia, myelodysplastic syndrome
Heinz bodies: G6PD
Dacrocytes: myelofibrosis
Codocytes: haemoglobinopathies, iron deficiency anaemia, hyposplenism, liver disease
Burr cells (echinocytes): uraemia, pyruvate kinase deficiency
Haemolytic anaemia
Jaundice + anaemia Hereditary: - membrane defects - metabolic defects - haemoglobinopathies Acquired: - autoimmune - isoimmune - drugs e.g. penicillin, quinine (RBC autoantibodies) - trauma (MAHA) - infection - Paroxysmal nocturnal haemoglobinuria
Sickle cell anaemia
African/Afro-caribbean
Symptomatic at altitude/hypoxia
Sickle cell crisis: acute chest syndrome, priaprism, joint pain
Hereditary spherocytosis
Osmotic fragility test +ve
Spherocytes on blood film
Splenomegaly
G6P deficiency
X-linked recessive
Triggers: moth balls/fava beans/nitrofurantoin/anti-malarials, infection
Heinz bodies
Autoimmune haemolytic anaemia
Coomb’s test: erythrocytes with antibodies
Cold-activated: mycoplasma
Warm-activated: CML/lymphoma/SLE
Paroxysmal Nocturnal Haemoglobinuria
Red discolouration of urine (haemoglobin and haemosiderin)
Ham’s test: lysis of erythrocytes in acidic solution
Haemolytic Uraemic Syndrome
Triad: acute renal failure, thrombocytopaenia, microangiopathic haemolytic anaemia
E.coli -> blood cell haemolysis
Trhombotic Thrombocytopenic Purpura
Pentad: HUS +CNS signs +fever
Clots, low platelets, rash
Disseminated Intravascular Coagulation
Septic/post-natal/vascular insult
Low fibrinogen + presence of clots
Anaemia of chronic disease
Rheumatoid arthritis
Cancer
Chronic inflammation
Aplastic anaemia
Pancytopaenia
Hypocellular bone marrow
Absent reticulocytes
Polycythaemia rubra vera
Uncontrolled RBC proliferation
JAK2 kinase/V167F mutation
Headaches, dizziness and strokes (viscosity)
Increased mast cells = pruritis after hot showers
Gout, splenomegaly, plethora
Secondary polycythaemia
Excessive RBC production due to other disease (COPD/EPO-secreting tumour)
Blood doping (athletes)
Sustained hypoxia
Immune Thrombocytopenic Purpura
Often idiopathic Menorrhagia, nosebleeds, purpura Associated with: - infections - autoimmune diseases - malignancy - drugs (quinine)
ALL
Children
Lymphadenopathy
Bone marrow failure: anaemia, neutropaenia, thrombocytopaenia
Blast cells
AML
Adults RARA-PML protein Auer Rods Sudan Black B stain (myeloblasts) Normocytic normochromic anaemia
APML
Treat with vitamin A and arsenic
tr(15,17)
CNS involvement
Skin rash, gum bleeding
CLL
Incidental finding
Raised WCC
Smear cells
CML
25-40 years Blast cells Philadelphia chromosome (BCR-ABL gene tr9,22) Imantinib 3 phases: chronic > blast > accelerated
Hodgkin’s lymphoma
Continuous spread Painful after EtOH Lymphadenopathy Hepatosplenomegaly Bone marrow failure Reed-Sternberg cells
Non-hodgkin’s lymphoma
Non-continuous spread
Burkitt’s lymphoma: mass on jaw, African descent
Marginal zone lymphoma: MALT
Diffuse Large B Cell lymphoma: hepatitis C
Multiple myeloma
CRAB
Bence Jones urinary protein
Plasma cells
Pathological fractures and back pain
Haemophilia
A: Factor 8 B: Factor 9 X-linked Deep bleeding: haemarthrosis APTT affected only
Von Willebrand disease
Superficial bleeding
Loss of vWF
Prolonged APTT and bleeding time
Vitamin K deficiency
Liver disease
Pancreatic insufficiency
Factor V Leiden
5% Caucasians
DVT <45yrs
Blood Group O
x4 increased clot risk
Antiphospholipid syndrome
Anti-cardiolupin Obstetric complications (multiple miscarriages) Thromboembolism events Thrombocytopaenia Livedo reticularis
