Reninoma: a Rare Cause of Curable Hypertension and Hypokalemia

L. Oei, A.H. van den Meiracker, E.H.G. Oei, A. Moelker, H.E. van der Wiel

Woensdag 20 april 2016

15:50 - 16:00u in Auditorium 2

Categorie├źn: Parallelsessie

Parallel sessie: Parallelsessie 2: Case reports/research

Case: A 30 year-old female had been diagnosed with hypertension for 5 years. Blood pressure was 172/130 mmHg using metoprolol 200 mg and perindopril 10 mg. She had headaches, palpitations, polydipsia, polyuria and panic attacks. Laboratory evaluation exhibited therapy-resistant hypokalemia with urinary potassium wasting. Screening revealed 4 times elevated renin (114 ng/l, reference 3.5-28.5) and aldosterone (2298 pmol/l, reference 56-660) levels. Radiological imaging showed no renal artery stenosis or coarctation of the aorta, but a 2 cm lesion was visualized in the upper pole of the left kidney. Renin sampling was indicative of a reninoma. Histopathological examination after partial nephrectomy confirmed the diagnosis of a reninoma. At follow-up, blood pressure and serum potassium normalized, antihypertensives could be discontinued and symptoms completely resolved.

Discussion: A reninoma is a tumor of juxtaglomerular cells producing excessive amounts of renin. Approximately one hundred case-reports have been published with a female-male ratio of 2:1. The mean age at presentation is 27 years, range 6-69 years. Presenting symptoms aside of hypertension are headache (48%), nausea (13%), polyuria and/or nycturia (11%), polydipsia (9%) and fatigue (7%). Median delay till diagnosis is 4 years. Computed tomography or magnetic resonance imaging is helpful in localizing the tumor, but imaging of small reninomas can be challenging.

Conclusion: We present a case of extreme secondary hyperaldosteronism caused by a reninoma. Screening for secondary causes of hypertension should be considered in severe hypertension, young age, therapy resistance or a combination with hypokalemia. Surgical resection of the reninoma yields curation in most cases.