An Unusual Cause of Severe Immunosuppression

Ectopic adrenocorticotropic hormone secretion (EAS) is a rare cause of endogenous Cushing’s syndrome and is associated with immunosuppression and opportunistic infections. We report the case of a person who presented with rapid onset of hypertension, diabetes mellitus, and severe hypokalemia in the context of significantly elevated adrenocorticotropic hormone (ACTH) levels and marked hypercortisolism. Subsequent investigations led to a diagnosis of EAS without an identifiable source. Her clinical status continued to deteriorate despite medical management of her hypercortisolemia, thus an urgent bilateral adrenalectomy was performed. This patient’s course was complicated by multiple opportunistic infections with cytomegalovirus, Pneumocystis jirovecii (PJP), Mycobacterium tuberculosis and possibly BK virus. To the best of our knowledge, this is the first description of this specific constellation of opportunistic infections in the setting of EAS. Our case highlights the need to consider multiple and rare opportunistic infections while managing EAS and supports early bilateral adrenalectomy in critically ill patients with EAS of unknown origin.