Endocrine Abstracts

Introduction: Iatrogenic Cushing’s syndrome (ICS) can be caused by virtually all forms of steroid treatment with or without suppression of hypothalamic–pituitary–adrenal (HPA) axis. Here we report betamethasone nasal drops used as treatment post septorhinoplasty as a cause of iatrogenic Cushing’s syndrome.

Case: A 36 years old female with background history of depression presented to endocrinology clinic for evaluation of progressive weight gain. She gained total of 12 kg over the course of 3 months following septorhinoplasty. During this period, she had been using betamethasone nasal drops, 3 drops each nostril 3 times daily. Physical examination revealed a cushingoid face, stretch marks and skin bruises without any evidence of proximal myopathy. Further work-up revealed low levels of basal adrenocorticotropic hormone (ACTH) of 7.1 ng/l, low DHEA Sulphate of 0.4 umol/l [NR 1.9 to 9.4] and very low morning cortisol of 63 nmol/l confirming the clinical diagnosis of iatrogenic Cushing syndrome. She was advised to stop her betamethasone nasal drops and was provided with prescription of tapering dose of oral prednisolone to avoid abrupt withdrawal of glucocorticoids that may evoke an adrenal crisis. Two months later, her HPA axis fully recovered with pre-prednisolone morning cortisol of 283 nmol/l and normal ACTH of 24.9 ng/l. She continued to lose weight and remained well during follow up without any need for further glucocorticoid therapy.

Conclusions: Any form of exogenous corticosteroids can result in Cushing’s syndrome if taken for prolonged periods. Betamethasone is an enantiomer of dexamethasone, so 1ml of these drops (the daily dose the patient took) would be the equivalent of 1 mg of dexamethasone. This case illustrates the ability of nasal corticosteroid drops to cause florid Cushing’s syndrome and prescribing clinicians should be made aware.