Endocrine Abstracts

Background: Cushing’s syndrome is defined as a hormonal disorder resulting from elevated serum cortisol leading to specific physical and biochemical abnormalities that might be detrimental to life itself. Majority is caused by steroid intake while endogenous sources although representing only a minority of patients often lead to delay in diagnosis. Ectopic ACTH syndrome considered a rare entity are usually found as small cell lung cancer and carcinoid tumors. Rare types of ectopic tumours are thymomas, pancreatic tumors, and medullary thyroid carcinomas. Knowing their rare presentations and diagnostic clues might help physicians in the future to easily diagnose and manage endogenous Cushing’s syndrome since most are completely reversible.

Case summary: A previously healthy 39 year-old Filipino female presented with rapid development of features compatible with Cushing’s syndrome (truncal obesity, buffalo hump, acne formation, moon facies, plethora, muscle wasting, acanthosis nigricans) in a span of 2 months. She also presented with metabolic alkalosis and significant hypokalemia leading to muscle paralysis. Significant hyperpigmentation of peculiar body sites (knuckles and toes) were observed. With further work ups and repeated hospitalizations, patient exhibited insulin resistance (secondary diabetes), hypertension, dyslipidemia and thyroid function abnormalities. Patient eventually referred to our institution for acutely worsening behavioural changes. Biochemical tests revealed elevated serum cortisol (12×), unsuppressed high dexamethasone suppression test and an elevated serum ACTH leading to a suspicion of a possible Ectopic-ACTH syndrome. Abdominal CT showed multiple liver masses. Patient eventually succumbed to nosocomial infection. On autopsy, an ectopic well differentiated neuroendocrine tumor was found at the pancreatic head with metastasis to the right hepatic lobe.

Conclusions: Knowledge of this disease and certain clinical clues and features (rapid clinical course, metabolic alkalosis with hypokalemia, severe hyperpigmentation, behavioural change) can guide clinicians to earlier diagnosis, rapid tumor location and immediate therapeutic initiation that can be life-saving.