A Report of 3 Cases of Adrenal Suppression Due to Glucocorticoid Hypersensitivity to Inhaled Corticosteroids

Children with moderate to severe asthma are treated with inhaled corticosteroids (ICS). Altered glucocorticoid sensitivity can cause suppression of the hypothalamic-pituitary-adrenal (HPA) axis in patients on ICS therapy. Our objective is to study glucocorticoid sensitivity in patients with asthma with suppressed HPA axes on ICS. We report 3 patients with suppressed HPA axes on ICS treatment and healthy controls. All subjects and controls underwent glucocorticoid sensitivity analysis using an in vitro fluorescein labeled-dexamethasone (F-DEX) mononuclear cell binding assay. Glucocorticoid sensitivity index (GCSI) was calculated as the area under the curve of the F-DEX assay results. Patients with GCSI ≤264 were classified as glucocorticoid resistant and those with GCSI ≥386 were classified as having increased glucocorticoid sensitivity. All 3 patients were found to have increased glucocorticoid sensitivity with GCSI of 424.9, 720.6, and 699.2 respectively. In conclusion, ICS therapy can lead to HPA axis suppression with varying degrees of adrenal insufficiency and therefore increased glucocorticoid sensitivity should be considered in such cases.