ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2017) 49 EP170 | DOI: 10.1530/endoabs.49.EP170

A rare cause of secondary endocrine hypertension in a young woman with hypokaliemia and recurrent transient ischemic attacks

Francisco Javier Martinez-Martin3, Sara Quintana-Arroyo1, Carmen Acosta-Calero1, Claudia Arnas-Leon1, Ana Delia Santana-Suarez1, Manuel Nivelo-Rivadeneira1, Agnieszka Kuzior1 & Elisa Gonzalez-Rodriguez2

1Endocrinology Department, Hospital Universitario de Gran Canaria Dr. Negrin, Las Palmas de Gran Ganaria, Spain; 2Endocrinology Department, Hospital Vithas Santa Catalina, Las Palmas de Gran Ganaria, Spain; 3Outpatient Hypertension Clinic, Hospital Universitario de Gran Canaria Dr. Negrin, Las Palmas de Gran Ganaria, Spain.

Clinical Case: A 39-year-old woman was referred to our Hypertension Clinic for workup after three episodes of TIA with SBP >180 mmHg in the last 6 months. Diagnosed and treated of hypertension and hypokaliemia since she was 15 years old, no secondary cause had been searched. She was treated with Telmisartan/Amlodipine/Hydrochlorothiazide 80/10/25 mg plus Carvedilol 12.5 mg BID and potassium supplements. She had no history of diabetes or dyslipidemia and did not smoke. Height was 168 cm, weight 63 kg, IMC 22.3 kg/m2, office BP 142/88 mmHg, HR 72 bpm. The physical exam was otherwise normal.

Treatment was changed to Diltiazem/Doxazosin for 3 weeks. Lab: normal including TSH and metanephrines, except venous pH 7.51, Cr 1.23 mg/dl, CKD-EPI eGFR 57 ml/min/1.73 m2, albuminuria 139 mg/g Cr, aldosterone 792 ng/ml, PRA 58 ng/ml per h, normal ratio (13.7).

Funduscopy: stage 2 hypertensive retinopathy, brain RMN: scattered white matter microinfarctions, heart US: normal function, mild LVH (LVMI 92 g/m2). Chest X-ray and abdominal US: normal.

AngioCT excluded renal artery sclerosis, but showed a 12 mm subcapsular mass in the right kidney. The adrenals were normal.

Renal venous sampling for renin: Peripheral 628 U/l (normal < 42), Left renal vein 645 right renal vein 3120 U/l; right/left ratio 4.8. Laparoscopic nodulectomy was performed; a encapsulated 14 mm adenoma with clean margins was obtained. It tested positive for renin.

Diagnosis: Secondary aldosteronism due to reninoma, resistant hypertension and target-organ damage (retinopathy, brain microinfarctions and TIAs, stage IIA CKD with microalbuminuria, LVH). Two months after surgery the patient is normotensive with manidipine 10mg/day: aldosterone, ARP, K+, venous pH and albuminuria are normal.

Commentary: Reninoma is rare but probably infradiagnosed, and a long diagnostic delay is not unusual. Even with well-controlled BP, it may cause severe organ damage due to hyperaldosteronism. Thus, it should be included in the workup of secondary hypertension.