Table 1.

HELLP and aHUS diagnostic criteria.

	HELLP	aHUS
Hemolysis	Plasma haptoglobin below limit for normal, plasma lactate dehydrogenase > 600 U/L	Non-immunological (Coombs test negative) hemolysis with red blood cell fragmentation > 1–2% in peripheral blood smear, plasma haptoglobin below limit for normal, and increased plasma lactate dehydrogenase
Organ dysfunction	Elevated liver enzymes: alanine aminotransferase > 70 U/L	Positive markers of injury (of any organ, but typically acute kidney injury with serum creatinine over 200 μmol/L)
Low platelets	<100 E9/L	Thrombocytopenia (platelet count below 150 E9/L or decrease over 25% from baseline)