Proteinuria as an Unusual Presentation of Pheochromocytoma in Pediatric Patient With Single Kidney.

Pheochromocytoma is a rare catecholamine-secreting tumor, particularly in pediatric populations, and often presents with sustained hypertension. We report the case of a 17-year-old male with a solitary kidney who presented with asymptomatic hypertension and unexpected nephrotic-range proteinuria. Imaging and biochemical workup confirmed a right adrenal pheochromocytoma. The patient underwent a successful laparoscopic adrenalectomy, after which his blood pressure normalized and proteinuria resolved. This case highlights a rare presentation of pheochromocytoma with heavy proteinuria, likely related to glomerular hyperfiltration secondary to hypertension and exacerbated by a solitary kidney. This case underscores the importance of considering pheochromocytoma in pediatric patients with unexplained hypertension, even in the presence of significant proteinuria.