Aetiology : Autoimmune disorder, Abs. against ADAMTS enzyms .
(This enz. normally clears VWF multimers to produce normal functional units and
its deficiency results in large VWF multimers which cross – link platelets and leads
to microvascular occlusion by plat. Thrombi e.g. brain, kidney).
Idiopathic, associated with drugs (Ticlopidine, Ciclosporine), HIV, Malignancy.
Clinically : Sporadic, Fluctuating, Familial: reported, F > M , young – adolescent
2. Anemia : Microangiopathic haemolytic (Fragmented RBCs) ,
↑ Retculocyte count, Jaundice, ↑ LDH, ‐ve coomb’s test.
3. Thrombocytopenia – Purpura, count usually < 20 X 109 /L
4. Neurological: Convulsion, Coma, Paralysis ( Transient or prolonged) ,
5. Renal : intermittent proteinuria, Renal Failure (more in HUS)
Lab.↑ WBC, ↓ plat.
PT, PTT ‐‐‐‐‐‐‐ Normal
B.M. ‐‐‐‐‐‐‐ Normal or increase cellularity
Gingival Biosy – Helpful
Untreated – 90% Mortality in 10 days
Treated – Mortality 20‐30% at 6 months
Sudden death due to cardiac Microthrombi
Plasmapharesis with FFP 12 bags/day for weeks – Months