Subtype identification is necessary for making diagnostic and therapeutic decisions in primary aldosteronism. We studied clinical, hormonal and histological features of sporadic solitary aldosterone- and cortisol-cosecreting (C/APA) adenomas in detail.
We here present the endocrine evaluation at baseline, after suppression with fludrocortisone and dexamethasone as well as after therapy with spironolactone and after unilateral adrenalectomy in two patients with (C/APA). Also, the expression of corticotropin- (MC2R) and angiotensin II type 1 (AT1R) receptors and 17α-hydroxylase in the tumors of these two patients was analyzed by immunohistochemistry.
Aldosterone, 18-hydroxycorticosterone (18-OH-B) and 18-hydroxycortisol (18-OH-F) were not suppressible with fludrocortisone in both patients and partially suppressible with dexamethasone in one patient. Aldosterone and hybrid corticosteroids returned to normal 8 weeks after adrenalectomy. In both cases, immunostaining showed a weak expression of AT1R and MC2R but strong expression of 17α-hydroxylase. The most common germline mutations in the aldosterone synthase gene and the aldosterone synthase/11β-hydroxylase hybrid gene were excluded.
These two cases document that sporadic A/CPA is a subtype of primary aldosteronism. Correct subtype identification is necessary to interprete adrenal venous sampling and to adequately treat adrenal insufficiency after operation. Presence of an A/CPA should be considered if a patient has i) primary aldosteronism and ii) hypercortisolism.
Prague, Czech Republic
24 - 28 Apr 2010
European Society of Endocrinology