Haematology Flashcards
1
Q
Conditions that falsely lower HbA1c
A
Haemolysis (inc hereditary spherocytosis) Sickle cell trait Certain haemoglobinopathies Acute blood loss Recent blood transfusion Hypertriglyceridemia Chronic liver disease
2
Q
Conditions that cause falsely high HbA1c
A
Iron deficiency Vitamin B12 deficiency Alcoholism Uremia Hyperbilirubinemia
3
Q
Prolonged PT and normal aPTT
A
Factor VII deficiency
Warfarin
4
Q
Normal PT and prolonged aPTT
A
VWD
Factor VIII, IX, XI, XII deficiency
Inhibitors
Heparin
5
Q
Prolonged PT and prolonged aPTT
A
Lupus anticoagulant (assoc. with thrombosis c.f. bleeding)
Deficiency of prothrombin, fibrinogen, factor V or X
Liver disease
DIC
6
Q
Conditions associated with Moya Moya disease
A
Down Syndrome
Neurofibromatosis Type 1
Sickle cell disease
William Syndrome
7
Q
Risk factors for developing Factor VIII inhibitors
A
- Number of exposure days (to exogenous factor) - usually develop within first 20 exposure days
- Factor mutation (variant) determines severity of disease –> more severe disease has greater risk of inhibitor development (e.g. large deletions or nonsense mutation)
- Immune response gene variations can contribute to inhibitor development e.g. HLA II, TNF-a, ILs, CTLA-4
- Race: African > Hispanic > Caucasians
- Age <5yo
- Recombinant factor > plasma-derived factor (SIPPET trial)
8
Q
Methaemaglobinemia
A
- Altered state of Hb –> Fe2+ (ferrous) is oxidised to Fe3+ (ferric) state and can no longer bind oxygen
- Remaining heme moiety in ferrous state (in the tetramer) has increased affinity for oxygen
- Shifts oxygen dissociation curve to the left
