[Primary hyperreninemia. An unusual cause of secondary arterial hypertension].

In 1975, scintigraphy revealed a 6.5 x 5 cm tumour in the region of the left adrenal in a 36-year-old man with known hypertension for 5 years (systolic pressure up to 250 mm Hg, diastolic up to 130 mm Hg). A laparotomy was performed for a suspected phaeochromocytoma. A tumour was located in the upper pole of the kidney and removed together with the kidney. The blood pressure quickly returned to normal after the operation: it remained stable for the following 17 years (between 130/80 to 150/90 mm Hg). Originally the tumour could not be clearly classified either clinically or histologically. But recently the paraffin-imbedded tumour specimen was re-examined by immunohistochemistry and in-situ hybridization. This identified a renin-producing tumour so that primary reninism was the cause of the arterial hypertension.