Haematology Flashcards
What is sickle cell anaemia?
Autosomal recessive condition that results for synthesis of abnormal Haemoglobin chain termed HbS
Results in sickle shaped red blood cells q
At what age do symptoms manifest in homozygous carriers for sickle cell and why
At 4-6 months
As this is when HbS takes over from fetal haemoglobin
What are the different types of sickle cell crises and what happens in them
Thrombotic crises - sickle cells causes vaso occlusion e.g, avascular necrosis of the hip
Sequestration crises - sickling in organs such as the spleen
Acute chest syndrome - sickling in pulmonary infiltrates leads to breathlessness and chest pain
Aplastic crises - caused by infection with parvovirus
How are sickle cell crises managed?
Analgesia Rehydration Oxygen Abx if evidence of infection Exchange transfusion - if there is complications
How is sickle cell managed long term?
Patient education about crises
Pneumococcal vaccine - aged 2, and then every 5 years
Hydroxyurea - increases HbF levels and is used in prophylactic management of sickle cell to prevent painful episodes
What is post thrombotic syndrome?
Complication following DVT
Symptoms may arise due to venous outflow obstruction and venous insufficiency e/g, heavy calves, pruritis, swelling, varicose veins
How is post thrombotic syndrome managed?
Compression stockings
What is the genetic inheritance of G6PD deficiency?
X-linked recessive
What are the clinical features of G6PD deficiency
Neonatal jaundice
Intravascular haemolysis
Gallstones - these are commonly seen
Splenomegaly
What would a blood film show in G6PD deficiency
Heinz bodies
Bite and blister cells may also be seen
What are the triggers for crises in G6PD deficiency?
Broad beans
Infections
Drugs - anti malarials e.g, quinone, sulph group drugs, ciprofloxacin
What is the genetic inheritance of hereditary spherocytosis?
Autosomal dominant
What are the clinical features of hereditary Spherocytosis
Failure to thrive
Jaundice
Gallstones
Splenomegaly
How does the mean corpuscular haemoglobin concentration help you to diagnosis hereditary spherocytosis ?
MCHC - elevated in HS
What is factor V Leiden?
Inherited thrombophillia
Mutation in factor V protein - which results in activated factor V being inactivated 10x more slowly by protein C
Also known as activated protein C resistance
What is the inheritance pattern of Von Willebrand disease?
Majority is autosomal dominant
Type 3 vWD (total lack of vWF) - this is autosomal recessive pattern
Types of Von Willebrand’s Disease
Type 1 - partial reduction in vWF (80% of patients)
Type 2 - abnormal form of vWF
Type 3 - total lack of vWF
Management of Von Willebrand Disease
Transexamic acid - used for mild bleeding
Desmopressin - acts to raise levels of vWF by inducing its release from endothelial cells
Factor VIII concentrate
What is polycythemia vera?
Neoplasm of bone marrow leads to excessive RBC production
Leads to increase in red cell volume
Often accompanied by overproduction in neutrophils and platelets
What is the genetic mutation seen in polycythemia vera?
JAK2 mutation
Clinical Features of polycythemia vera
Hyperviscosity
Itching - after exposure to hot water or in humid weather
Splenomegaly
Haemorrhage - due to abnormal platelet function
Plethoric (red) appearance/skin colour
Hypertension
Low ESR
Clinical Features of Multiple Myeloma
C - hypercalcemia
R - renal impairment
A - anaemia
B - bone disease e.g, osteoporosis, pathological fractures, osteolytic lesions
What investigation is diagnostic for multiple myeloma
Serum electrophoresis - will show monoclonal proteins (IgG or IgA) and bence jones proteins
What is the X-Ray pattern seen in multiple myeloma
Rain-drop skull (pattern of dark spots)
