Thrombocytopenia - Thrombotic Thrombocytopenic Purpura (TTP)

Question 1

Definition

Answer 1

Rare, serious blood disorder where many small blood clots form in the smallest arteries throughout the body

Question 2

Epidemiology

Answer 2

Immune TTP: More common in late childhood or adulthood
Congenital TTP: present from birth
Females
Associated with HIV, cancer, and SLE

Question 3

Aetiology

Answer 3

Cause unknown but is suggested to be due to severe deficiency in ADAMTS13 which breaks down VWF

Question 4

Pathology

Answer 4

Two types of TTP
Immune TTP = more common, where body develop autoantibodies against ADAMTS13
Congenital TTO = autosomal recessive condition where child has little to No ADAMTS13
ADAMTS13 usually inactivated VWF and reduces platelet adhesion to vessel walls. Shortage causes platelets aggregation and RBC destruction leading to thrombocytopenia and haemolytic anaemia

Question 5

Signs and symptoms

Answer 5

Decreased platelets
- purpuric rash, fever, weakness, pallor, fatigue, heavy bleeding, Abdo pain, N+V
Neurological issues
- headaches, confusion, speech abnormalities, coma, partial paralysis, seizures, coma
Microangiopathic haemolytic anaemia
AKI happens in <10% due to lack of blood and urine filtration = increased water, salt and protein retention
- oedema, SOB, headache, fever, cardiac arrhythmia

Question 6

Diagnosis

Answer 6

FIRST LINE + GOLD STANDARD = FBC: thrombocytopenia, and haemolytic anaemia (normocytic, normochromic)
Low ADAMTS13 <10%
Blood film: schistocytes (fragmented red blood cells), unconjugated billirubin raised,

Question 7

Treatment

Answer 7

ITTP: Plasma exchange (plasmapheresis)
Steroids PREDNISOLONE
RITUXIMAB
CTTP: plasma infusions