Endocrine Abstracts

Background: Biochemical evidence of adrenal insufficiency (AI) is reported commonly during inhaled corticosteroid (ICS) treatment for asthma. The significance of mildly abnormal results is uncertain. For this reason we adopt a stratified approach to the management of patients with impaired cortisol responses to the low dose short Synacthen test (LDSST): Patients with peak cortisol 350–499 nmol/l (‘suboptimal’) receive hydrocortisone 20 mg/m² per day during sick days only, patients with peak cortisol 100 nmol/l and peak cortisol >500 nmol/l are considered normal. Recovery of adrenal function during this treatment regimen has yet to be reported.

Aims: To describe recovery of adrenal function in children with AI treated according to this protocol.

Design: Retrospective observational study.

Methods: The results of LDSSTs, performed between 2008 and 2016 in selected children with asthma, taking high dose ICS or with symptoms of AI, were studied.

Results: Two hundred and thirty eight tests in 113 (74 M) children, age 10.4 (3.3–16.5) years, 2.1(1–7) tests/child. Duration of follow up: 2.2(0.2–7.7) years. Abnormal baseline test: N=17 (12 M), 15%, age 8.6 years (3.3–16.5), ICS dose (beclomethasone equivalent) 800 mcg/day (200–1000). Repeat tests: N=17, normal in six (35%) patients, suboptimal in seven (41%), abnormal in four (24%). Suboptimal baseline test: Suboptimal: N=54 (37 M), 48%, age 10.9 years (4.7–15.6), ICS dose 800 mcg/day (200–1000) Repeat tests: N=50 (93%), normal in 36 (72%), suboptimal in 11 (22%), abnormal in three (6%). Normal baseline test: N=42 (25 M), 37%, age 10.4 years (3.8–14.8), ICS dose 500 mcg/day (100–1000) Repeat tests: N=6 (14%), normal in three (50%), suboptimal in two (33%) abnormal in one (17%). Basal and peak cortisol levels increased by >15% (2x inter-assay coefficient of variation) in 33/73 (45%) and 42/73 (57%) subjects respectively, and decreased by >15% in 14/73 (19%) and 7/73 (10%) respectively. A statistically non-significant fall in height SDS (baseline −0.2 (−1.7 to +2.5), follow up −0.7 (−1.9 to +2.9)), of uncertain clinical significance was observed in patients treated with daily hydrocortisone only. BMI SDS did not change in any diagnostic group.

Conclusion: Recovery of adrenal function is common during this treatment regimen.