26th April 2024

A 58-year-old man presents with intermittent, crampy abdominal pain for two weeks.

A 58-year-old man presents with intermittent, crampy abdominal pain for two weeks. He reports increased bowel movements, often with mucus. He has a history of constipation but denies recent weight loss or rectal bleeding. His temperature is 37.5°C. On examination, he has mild tenderness in the left lower quadrant without rebound or guarding. Laboratory tests show mild leukocytosis.

Which is the most likely cause of his symptoms?