Reninoma: a rare cause of curable hypertension

Abstract

The most common type of refractory hypertension found in children is secondary hypertension, which is a potentially curable disease. Reninoma, a renin-secreting juxtaglomerular cell tumor, is a rare cause of severe hypertension that is usually diagnosed in adolescents and young adults. Surgical resection of the tumor completely cures the hypertension of patients with reninoma. The typical clinical presentation of reninoma includes hypokalemia, metabolic alkalosis, and features secondary to the increased activation of the renin-angiotensin system without renal artery stenosis. We report a case of reninoma in a female adolescent with a typical clinical presentation, in which surgical removal of the tumor completely cured hypertension. We discuss here the clinical features, imaging studies, and immunohistochemical examination of the tumor used to establish the diagnosis of reninoma and for the management of the condition.

Keywords: Hypokalemia; Juxtaglomerular apparatus; Renal hypertension; Renin.

Fig. 1.

Renal Doppler ultrasonographic images show: (A) a bilobed cyst measuring 2.79 cm×1.88 cm at the lower pole of the right kidney and (B) that the renal arterial flow is intact.

Fig. 2.

Computed tomography angiography images obtained in the arterial phase (A) and magnetic resonance images obtained in the portal (delayed) phase (B) show a mass-like lesion (white arrows) with an internal cystic area and peripheral eccentric soft tissue.

Fig. 3.

Histopathological examination of the resected tumor shows: (A) the gross appearance of a cross-section of the partial nephrectomy specimen in which a well-circumscribed mass with a partially cystic cut surface can be observed, (B) the sheets of polygonal tumor cells (H&E, ×200), and (C) that the tissue stained positive for CD34 (×200).