Endocrine Abstracts

Controversy exists as to the role of adrenal venous sampling in the assessment of primary aldosteronism (PA). There is no consensus as to how best to define successful outcome post resection of aldosterone producing adenoma (APA). We performed a retrospective analysis of the outcome of patients following unilateral adrenalectomy without pre-operative venous sampling. The study included 14 patients (9 males; mean age 47 yrs (r: 38–59 yrs) with PA and CT identified unilateral adrenal adenomas. Post-operative follow-up was between 4–13 weeks (1 patient lost to follow-up).

All had hypertension (10/14 for ≥5 year; 11/14 needing ≥2 antihypertensives) and 12/14 had hypokalaemia at presentation. Adenoma size on CT was 1.0–4.5 cm; 8/14 adenomas were ≥1.5 cm. A solitary adrenal nodule was identified in all excised glands.

Immediately post-operatively 12/14 patients were normokalaemic and at subsequent review all remained normokalaemic without potassium-sparing medication. Systolic and diastolic blood pressures fell by 10 mmHg and 3 mmHg respectively. 8/13 patients were normotensive off hypertensive medication. 5/13 patients required 1–3 less antihypertensives. 3/5 patients remaining on medication had comorbidities, e.g. IHD or DM. 6/14 patients had aldosterone/renin ratio (ARR) measured after the operation; all were normal, highest being 375 units.

Adrenal venous sampling is not necessary in PA with clear unilateral adrenal pathology. We need to be able to define successful outcome post-resection of APA. We generally advocate discontinuation of anti-hypertensives at discharge and recommend that the BP, K⁺, and ARR are re-measured between 6–12 weeks post-operatively.