Table 1.

Clinical and laboratory features of TA-TMA: differential diagnosis and evaluations.

Clinical sign (in typical order of presentation)	Clues/tips	Differential diagnoses	Useful evaluations
THE TA-TMA “TRIAD” (PRESENT IN ALMOST ALL CASES)
Hypertension (>95% for age, sex, height)	Requiring >1 BP Med (or >0 if not on a CNI/steroids)	CNI, Steroids
de novo Thrombocytopenia/platelet transfusion refractoriness	No rise in platelet count the day after transfusion	SOS, Anti-platelet antibodies	Bilirubin, liver US Post-transfusion count Immature platelet fraction
Elevated LDH (>ULN for age)	Need to monitor twice weekly & trend	Liver injury, AIHA	Liver enzymes Direct antiglobulin test
OTHER FINDINGS
Proteinuria (≥30 mg/dL)	Need to monitor UA daily Send Urine Protein/Cr if UA positive	Cystitis	Urine and blood PCR for BK virus & adenovirus
Elevated D-dimers	Need to monitor twice weekly and trend	Sepsis/DIC, SOS	Blood cultures
Falling haptoglobin	May rise first as an inflammatory acute phase reactant, such that the fall can be late	AIHA	Direct antiglobulin test
New Anemia/increased RBC transfusion needs		AIHA	Reticulocyte count
Rising creatinine	Late finding	CNI, Other meds (anti-virals), BK nephritis	Blood PCR for BK virus
Schistocytes	Often absent	Fairly pathognomonic, when present

Bold, Part of Current Diagnostic Criteria of Jodele et al. (2) along with sC5b9, though not all required to be present in order to make the diagnosis. BP, blood pressure; CNI, calcineurin inhibitor; SOS, sinusoidal obstruction syndrome; US, ultrasound; LDH, lactate dehydrogenase; ULN, upper limit of normal; AIHA, autoimmune hemolytic anemia; UA, urinalysis; DIC, disseminated intravascular coagulation; RBC, red blood cell.