PLASMIC Score for Estimating the Likelihood of Severe ADAMTS13 Deficiency in Adults with Suspected TTP

 

		Platelet count <30,000/microL
		One or more indicators of hemolysis:       Reticulocyte count (percentage) >2.5%; or       Haptoglobin undetectable; or       Indirect bilirubin >2.0 mg/dL [>34 mcmol/L]
		No active cancer in the preceding year
		No history of solid organ or hematopoietic stem cell transplant
		Mean corpuscular volume (MCV) <90 femtoliters
		International normalized ratio (INR) <1.5
		Creatinine <2.0 mg/dL [<177 mcmol/L]

 
Important: Inputs must be complete to perform calculation.

 

Total Criteria Point Count:
 

 

Interpretation

 

PLASMIC score (points)	Risk of severe ADAMTS13 deficiency
0 to 4	Low risk
5	Intermediate risk
6 to 7	High risk

 

Notes

• Each criterion, if present, contributes one point to the total criteria point count. One point is added for one or more of the "Indicator of hemolysis" subcriteria, if present.
• TTP: thrombotic thrombocytopenic purpura.
• ADAMTS13: a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13.

 

References

1. Bendapudi PK, Hurwitz S, Fry A, et al. Derivation and external validation of the PLASMIC score for rapid assessment of adults with thrombotic microangiopathies: a cohort study. Lancet Haematol. 2017 Apr;4(4):e157. PubMed ID: 28259520