A patient with a bronchial carcinoid presents with Cushingoid symptoms due to an atypical and potentially dangerous supplement

Well differentiated bronchial neuroendocrine neoplasms often follow a clinically indolent course and rarely cause Ectopic ACTH syndrome. Iatrogenic corticosteroid use is the most common cause of Cushing syndrome and should be considered in all patients regardless of clinical background. A 59 year old woman with an 11 year history of a 1.5 cm well differentiated bronchial carcinoid, presented with Cushingoid features. Laboratory results were not consistent with an ACTH dependent Cushing Syndrome and exogenous steroids were suspected. The patient received an FDA alert regarding a glucosamine supplement she had started 4 months prior for joint pain. Ectopic ACTH production is reported in less than 5% of patients with squamous cell lung cancer and 3% of patients with lung or pancreatic (non-MEN1) neuroendocrine tumors. Factitious corticoid exposure is rare and can be evaluated with synthetic corticosteroid serum testing. Cushing syndrome due to supplements containing unreported corticosteroid doses should be considered in patients with typical Cushingoid features and contradictory hormonal testing. •The most common cause of ectopic ACTH syndrome is pulmonary carcinoid tumors and squamous cell lung cancer; however it is a relatively uncommon complication of pulmonary neoplasms.•The most common cause of Cushing syndrome is iatrogenic corticosteroid use and it should be considered in all patients regardless of clinical background.•Low urine cortisol levels may be associated with exogenous glucocorticoid exposure.•Occult glucocorticoid exposure is rare but can be evaluated with liquid chromatography.•Consumers should be aware of the potential risks of taking supplements, especially those advertised as joint pain relief products.