Endocrine Abstracts

Introduction: The diagnosis of primary hyperaldosteronism (PAH) is based on the realization of the renin aldosterone ratio (RAR). The presence of renal insufficiency (RI) in a hypertensive patient complicates this diagnosis by affecting various biological assays.

Observation: We report the case of 25-year-old female, with a personal history of primary hypothyroidism, hypertension diagnosed at age 21 and severe renal insufficiency developed during a pregnancy carried to term at the age of 22. Creatinine clearance was 24 ml/min with a tendency to hypokalaemia. Computed tomography of the adrenal glands revealed a 17 mm left adrenal adenoma. The biological assessment showed an excess of aldosterone (2481 pmol/l) with an unsuppressed renin activity (16.02 mIU/l). The RAR came back positive at 154.69 (n<64). The diagnosis of Conn’s syndrome was retained. The patient underwent left adrenalectomy with improvement in blood pressure and renal function.

Discussion: The interpretation of the RAR in the context of renal failure is difficult with few data in the literature. It has been previously reported that the RAR is higher in renal failure with a risk of false positives. Recent work has shown that renal insufficiency is on the contrary responsible for a reduction in the RAR by an increase in renin with a risk of false negative results. In renal impairment, lower RAR thresholds should be considered.