Thrombotic microangiopathic nephropathy, pulmonary hypertension and nephromegaly: case report of a patient treated with endothelin receptor antagonist

The coexistence of thrombotic microangiopathic nephropathy and pulmonary hypertension has only been described in association with malignancy and its treatment. Here we describe a 14-year-old boy with no prior medical history who presented with hypertension, proteinuria and nephromegaly, and then developed progressive pulmonary hypertension. Renal histology showed lesions consistent with glomerulopathy due to thrombotic microangiopathy (TMA). Pulmonary hypertension was controlled by the use of an oral endothelin receptor antagonist (bosentan). Although renal function deteriorated at the onset of pulmonary hypertension, an improvement was observed after the bosentan treatment. Nephromegaly persisted, but current creatinine clearance values are within the normal range. While this case exemplifies how thrombotic microangiopathic nephropathy may be associated with pulmonary hypertension, a therapeutic role of endothelin antagonists is suggested, not only for pulmonary hypertension but also for microangiopathic nephropathy.