Endocrine Abstracts

Background: Primary hyperaldosteronism (PHA) is characterised by inappropriately high aldosterone production, most commonly caused by unilateral/bilateral adrenal adenoma or bilateral adrenal hyperplasia. It usually manifest as hypertension and/or hypokalaemia. There is emerging evidence to support the prevalence of PHA in more than 10% in hypertensive patients but only a minority will have a confirmed diagnosis and receive specific treatment.

Aim: To process map our patients suspected to have PHA on the initial screening test.

Methods: Retrospective analysis of 149 patients, who underwent screening for suspected PHA.

Results: 149 patients (48% male and 52% females) with youngest aged 17 and the oldest aged 89 years. 53% were screened for secondary hypertension; 38% for adrenal lesions. 80% had hypertension; 66% had details on antihypertensive; 39% were using single agent; 27% double agents; and 34% were using ≥3 agents. 98% had serum potassium available and 22% were hypokalaemic (K+ < 4 mmol/l). 40% had specific adrenal imaging: 61% had unilateral disease; 17% had bilateral disease; 20% had normal adrenals; and in 2% details were not available. 27% patients had aldosterone ≥400 pmol/l with Aldosterone Renin Ratio (ARR) of ≥30 consistent with PHA and 4% patients had aldosterone in the range of ≥250 pmol/l - 399 pmol/l with ARR of ≥30 where PHA could not be excluded. Only 26% of them proceeded to have saline infusion test for biochemical confirmation, 9% had adrenal venous sampling (AVS) and none underwent 11C-Metomidate PET CT.

Conclusions: Currently only minority of eligible patients proceed to confirmatory tests, AVS and 11C-Metomidate PET CT. Difficulties in biochemical interpretation with interfering medications, technical difficulty with AVS, lack of access to specialised services contribute towards treatment inertia in these patients. Discussing these patients in the adrenal MDT and having a dedicated pathway helps patient selection for appropriate treatment.