ESPE Abstracts

Objective: Treatment of primary adrenal insufficiency (PAI) is often challenging in patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED or APS1). In addition, electrolyte levels often fluctuate in APECED patients. This study aimed to describe adrenal steroid and electrolyte levels in patients with APECED.

Design: This cross-sectional study included 43 Finnish patients with APECED (27 females, 7 under 18 years of age) and 68 age- and gender-matched healthy adult control subjects (43 females). We determined serum adrenal steroids, plasma renin, sodium, potassium, and creatinine concentrations, as well as blood pressure in all study participants. Mann-Whitney U-test was used to determine differences between the groups.

Results: Patients’ median age was 39.1 years (range 7.0-70.1); 35 (81%) had PAI. Patients with PAI had, in comparison with non-PAI patients, significantly lower serum cortisol, cortisone, aldosterone, DHEA, androstenedione, and cortisol-to-cortisone ratio. Plasma renin and electrolyte levels did not differ between PAI and non-PAI patients. When we compared adults with PAI with adult control subjects, we found that serum concentrations of all adrenal steroids, plasma potassium (P < 0.001), and cortisol-to-cortisone ratio (P = 0.014) were significantly lower in PAI patients. Plasma sodium (P < 0.001) and creatinine (P = 0.003) were significantly higher in patients with PAI compared with controls. When we compared adult non-PAI patients (n = 6) with adult controls, we found that concentrations of cortisone [median (range); 46.0 (2.3-72.5) vs 66.5 (40.0-89.0) nmol/l, P = 0.004], DHEA [6.0 (0.6-20.2) vs 17.3 (3.1-61.7) nmol/l, P = 0.011], and potassium [3.5 (3.0-4.0) vs 3.7 (3.1-4.3) mmol/l, P = 0.036] were lower in patients. Their plasma creatinine was also higher (P = 0.013) compared with controls. Three non-PAI patients with low levels of DHEA and/or DHEAS had autoantibodies against 21-hydroxylase at the age of 23.0-62.7 years, and none had antibodies against side-chain cleavage enzyme. Blood pressure levels did not differ between any groups.

Conclusions: Concentrations of adrenal steroids and electrolytes differed between PAI and non-PAI patients but also between non-PAI patients and healthy controls. We found significantly lower concentrations of serum DHEA and plasma potassium in patients without PAI in comparison with the controls. Low adrenal androgens associated with autoantibodies against 21-hydroxylase in three patients without PAI, possibly reflect eventual gradual development of adrenal insufficiency.