Haematology Flashcards
Describe the common pathway of the coagulation cascade
Intrinsic and extrinsic: Factor X > Factor Xa
Factor II (Prothrombin) > (Xa) > Factor IIa (Thrombin)
Fibrinogen > (IIa) > Fibrin
Factor XIII > Factor XIIIa
Fibrin > (XIIIa) > Fibrin clot
Name four causes of neutropenia
Infection e.g. EBV
Drugs e.g. phenytoin
Autoimmune
Myeloma
Name four causes of lymphocytopenia
Drugs e.g. steroids
Infection (post viral is common)
Renal impairment
Rheumatoid e.g. SLE, RA
Name four causes of neutrophilia
Infection e.g. bacterial
Drugs e.g. steroids
Leukaemia
Inflammation e.g. rheumatoid arthritis
Name four causes of lymphocytosis
Infection e.g. EBV
Stress
Vigourous exercise
Malignancy (CLL/ALL)
Name four causes of monocytosis
Malaria
Typhoid
TB
Myelodysplastic syndromes
Name four causes of eosinophilia
Asthma
Parasitic infections
Drugs e.g. peniciloin
Smoking
Name four causes of thrombocytopenia
Problems with production:
Viral infection e.g. EBV
Sepsis
B12/folate deficiency
Problems with destruction:
Drugs e.g. NSAIDs
Alcohol
ITP
Name four causes of thrombocytosis
Inflammation
Haemorrhage
Splenectomy
Iron deficiency
Name four things that cause PT/INR levels to change
Warfarin
Vitamin K deficiency
Liver disease
Disseminated intravascular coagulation
What does PT/INR measure?
The time taken for a blood clot to form via the EXTRINSIC pathway
Overall clotting factor synthesis/consumption
What does APTT measure?
(Activated partial thromboplastin time)
The time taken for blood to clot via the INTRINSIC pathway
Indicates issues with factors VIII, IX and XI:
- Haemophilia A (VIII)
- Haemophilia B (IX)
- Haemophilia C (XI)
- Von Willebrand’s disease (vWF pairs with factor VIII)
What does bleeding time measure?
Overall platelet function and levels
Measure of how long it takes a patient to stop bleeding from a wound
Platelet specific disorders increase bleeding time e.g. vWF disease, ITP, DIC, thrombocytopaenia
What does thrombin time measure?
How fast fibrinogen is converted to fibrin (by thrombin)
Prolonged by DIC, liver failure, malnutrition, and abnormal fibrinolysis
Name four causes of microcytic anaemia
TAILS:
Thalassaemia Anaemia of chronic disease Iron deficiency anaemia (most common cause) Lead poisoning Sideroblastic anaemia
Name four causes of normocytic anaemia
Acute blood loss
Anaemia of chronic disease
Haemolytic anaemia
Hypothyroidism
Pregnancy
Bone marrow failure
Renal failure
Two types of macrocytic anaemia
Megaloblastic
Normoblastic
Name two causes of megaloblastic macrocytic anaemia
B12 deficiency
Folate deficiency
Name four causes of normoblastic macrocytic anaemia
Alcohol excess (affects bone marrow) Liver disease Iatrogenic e.g. azathioprine Reticulocytosis Hypothyroidism
Name four symptoms of anaemia
Fatigue Shortness of breath (dyspnoea) Palpitations Anorexia Headache Faintness
Name four signs of anaemia
Pallor e.g. conjunctival
Tachycardia
Hyperdynamic circulation e.g. systolic flow murmur
Raised respiratory rate
Name four causes of iron deficiency anaemia
Blood loss (most common cause in adults) e.g. GI bleed
Insufficient dietary iron (most common cause in children)
Increased requirements e.g. pregnancy
Inadequate iron absorption e.g. coeliac disease, IBD
Name three specific signs of iron deficiency anaemia
Koilonychia
Angular cheilosis
Atrophic glossitis
Blood film signs of megaloblastic macrocytic anaemia
Hypersegmented neutrophils and oval macrocytes
Mediastinal lymphadenopathy
Hodgkin lymphoma (85%)
Primary haemostasis
Initiation and formation of the platelet plug (platelet activation)
Secondary haemostasis
Formation of fibrin clot (coagulation cascades)
Dabigatran
Inhibits thrombin (DIRECT/DOAC)
Initial activation of platelets
Collagen binding to GPIIb/IIIa via vWF
Two hallmarks of AML
Gym hypertrophy
Auer rods
Most common leukaemia in children
ALL
Multiple myeloma features
Old CRAB Age (>65) Calcium (hypercalcaemia) Renal Anaemia Bone lesions
Multiple myeloma protein found in urine
Bence-Jones protein
Hodgkin lymphoma hallmark features
Lymphadenopathy painful after drinking alcohol
Reed-Sternberg cells
Bimodal distribution (early 20s and then 70s)
Ann Arbor staging for lymphoma
Stage 1: single lymph node
Stage 2: 2 or more (same side of diaphragm)
Stage 3: 2 or more (both sides of diaphragm)
Stage 4: extralymphatic
Blood test results for DIC
Thrombocytopenia Long PT Long APTT Low fibrinogen Raised D-dimer
Mutation in polycythaemia vera
JAK2
Polycythaemia definition
High concentration of erythrocytes in the blood
Monoclonal gammopathy of undetermined significance (MGUS)
Close link to multiple myeloma (1% of cases develop into myeloma)
Philadelphia chromosome association
Chronic myeloid leukaemia
t (9;22)
Most common type of leukaemia in adults
AML
Blood film CLL
Smudge cells (abnormally fragile lymphocytes)
Bone marrow biopsy AML
Auer rods
ALL Px
Anaemia Bleeding/bruising (thrombocytopenia) Infections (neutropenia) Hepatosplenomegaly Lymphadenopathy CNS infiltration > headaches, CN palsies Associated with Downs Syndrome