Haematology Flashcards
What are the types of HITT
Type 1 is non immune mediated - occur g at 3 days
Type 2 is immune mediated at 5-10 iGg
Pathophysiology of HITT
Heparin bind to platelet factor 4
The complex is immunogenic and activates iGG hit antibodies
This causes platelet activation and thrombosis
What is included in the Warkentin hit score
Thrombocytopenia
Timing
Thrombosis
Other potential cause a
What lab tests confirm hit
Immunoassay for hit antibodies
Functional platelet assays
What is haemolytic uraemic syndrome
Micro angioplasty is haemolytic anaemia
Thrombocytopenia
Renal failure
What causes haemolytic uraemic syndrome
Epidemic or atypical
Epidemic - prodromal bloody diarrhoea and E. coli
Atypical rare and worse - strep, hiv, bmt, cancer
Pathophysiology of Haemolytic uraemic syndrome
Exposure to toxin
Bloody diarrhoea due to haemorrhaging colitis
aki secondary to toxin mediated vascular endothelial damage
Platelet aggregation- > thrombi -> compliment
Treatment of haemolytic uraemic syndrome
Cipro for e.coli
Plasma exchange - Mainly for atypical
What is thrombotic thrombocytopenic purpura
Maha Thrombocytopenia Aki Fluctuating consciousness Fever
Pathophysiology of ttp
Deficiency in ADaMTS 13
vWF not cleaved
Large multimers and no cleaving therefore uncontrolled platelet activation
Fibrin deposited forming a mesh that shreads red cells
Management of ttp
Plasma exchange continue 2 days after plts >150
Methyl pred
Retuximab if relapse
Aspirin and thromboprophalycis once plts > 50
Definition of Anaemia
Men 130
Women 120
Define sickle cell disease
Chromosome 11
Autosomal recessive
Hb S is less soluble and more viscous and tends to polymerise - distorts it’s contour
Presentations of sickle cell
Vaso- occlusive
- acute chest syndrome
- Stoke
- long bone ischaemia
- aki
Sequestration
- anaemia, hypotension and enlarged spleen
Aplastic
- red cell aplasia
- parvo B19 / folate
define thalasaemia
2 types- alpha and beta
Alpha - deletion of 1-4 alpha chains
Beta- reduced beta and increased alpha and gamma
Minor or major
Define factor 5 Leiden
Autosomal dominant
Mutates factor 5 therefore activated protein c cannot bind to it resulting in ongoing clot formation
Present with venous thrombus
Define anti phospholipid syndrome
Autoimmune hypercoaguloable state due to excess antiphospholipid antibodies
Arterial and venous thrombosis
Define haemophilia
X linked recessive
A - factor 8
B -factor 9
Define von willrbrands disease
Autosomal dominant
VWF needed for platelet adhesion to the endothelium and to bind to factor 8 to prevent its breakdown
Define DIC
Acquired syndrome characterised by a dyregulated host response to a trigger resulting in intravascular coagulation, damaged microcasculature and organ dysfunction
Triggers for DIC
Sepsis
Trauma
Obstetric emergencies
Pathophysiology of DIC
Excessive thrombin production
Excessive fibrinolysis
Thrombosis and bleeding
Loss of localisation
What is cross matching
Mixing donor cells with recipient serum and observing for signs of agglutination
Which blood group is the universal donor
O-
