Severe renal failure and thrombotic microangiopathy induced by malignant hypertension successfully treated with spironolactone.

Malignant hypertension can cause thrombotic microangiopathy (TMA) characterized by hemolytic anemia and thrombocytopenia. On the other hand, severe hypertension is sometimes associated with hemolytic uremic syndrome (HUS) or thrombotic thrombocytopenic purpura (TTP). Distinguishing these entities is important because of therapeutic implications. Plasmapheresis should be initiated as soon as possible if we are dealing with TTP. We describe the case of a 30-year-old man referred to our hospital with malignant hypertension, severe renal failure and TMA: haemoglobin=9g/dL, total bilirubin=0.4mg/dL, haptoglobin≤10mg/dL, platelet count=59,000/µL and schistocytes on peripheral smear. He required initiation of hemodialysis. Additionally, we considered that the possible cause of TMA was malignant hypertension according to the presence of hypertensive retinopathy and thrombocytopenia which remitted only with blood pressure control, hence, plasmapheresis was not given. Renal function did not improve and the patient remained chronic hemodialysis. Intensive therapy for hypertension with a combination of antihypertensive drugs including spironolactone successfully lowered his blood pressure without developing hyperkalemia.