Iatrogenic Cushing Syndrome With Hypothalamic-Pituitary-Adrenal Axis Suppression in a Two-Month-Old Infant Following Unsupervised Topical Corticosteroid Use: A Case Report

Topical corticosteroids are commonly prescribed in pediatric dermatology; however, systemic adverse effects may occur rapidly in infants due to increased percutaneous absorption, the occlusive effect of diapers, and the immaturity of the hypothalamic-pituitary-adrenal (HPA) axis.We report the case of a two-month-old, 6 kg male infant who developed iatrogenic Cushing syndrome following approximately seven weeks of daily and repeated unsupervised application of a betamethasone valerate 0.1% topical corticosteroid to the diaper area for the treatment of diaper rash.Clinical examination revealed moon facies, a buffalo hump, and faciotruncal obesity.Laboratory evaluation showed suppressed morning cortisol at 5 µg/L (reference: 50-230 µg/L) and undetectable adrenocorticotropic hormone (ACTH) at 2.47 pg/mL (reference: 7-63 pg/mL), consistent with secondary adrenal insufficiency due to HPA axis suppression; brain CT showed no structural abnormality of clinical relevance.Management consisted of gradual withdrawal of the topical corticosteroid over four weeks, physiologic hydrocortisone replacement therapy at 8-10 mg/m²/day in three divided doses, and close clinical and biochemical follow-up.Biochemical recovery was suggested by normalization of morning cortisol to 272 µg/L, allowing progressive tapering and the discontinuation of hydrocortisone over six weeks without any episode of acute adrenal insufficiency.The family received structured education regarding the risks of unsupervised corticosteroid use and the warning signs of adrenal crisis.This case underscores that even moderate-to-potent topical corticosteroids applied to occluded skin areas can cause significant systemic toxicity in this vulnerable population and highlights the critical importance of parental education, appropriate prescribing guidance, and vigilant monitoring to prevent this avoidable complication.