28th July 2023

A 45-year-old man presents with a 6-month history of intermittent fever associated with episodes of bloating and diarrhoea.

A 45-year-old man presents with a 6-month history of intermittent fever associated with episodes of bloating and diarrhoea. He has a White British background. He also reports some weight loss and appears to have a horizontal gaze ophthalmoplegia on the exam. Investigations are done – faecal calprotectin is normal, and HIV testing is negative. A duodenal biopsy shows periodic-acid Schiff positive macrophages.

What is the most likely cause?

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