The PLASMIC score for prediction of TTP with severe ADAMTS13 deficiency

One point each awarded for the following:

Platelet count < 30,000/uL

Evidence of hemolysis (retic count > 2.5%, undetectable haptoglobin, or indirect bili > 2.0)

No active cancer

No history of solid-organ or stem-cell transplant

MCV < 90 fl

INR < 1.5

Creatinine < 2.0 mg/dL


A score of 0-4 indicates low risk of severe ADAMTS13 deficiency

Score of 5 is intermediate risk

Score of 6 or 7 indicates high risk


Reference: Lancet Haematol 2017;4:e157-e164