26th April 2024

A 28-year-old male, with a known history of Crohn’s disease, presents with a 6-week history of increasing abdominal pain, fever, and a palpable mass in the right lower quadrant of the abdomen.

A 28-year-old male, with a known history of Crohn’s disease, presents with a 6-week history of increasing abdominal pain, fever, and a palpable mass in the right lower quadrant of the abdomen. He mentions a recent reduction in bowel frequency and a change in stool calibre. He denies any rectal bleeding, vomiting, or significant weight loss. His appetite has decreased and he feels generally unwell. His temperature is 37.6°C and pulse rate is 90 bpm. He is currently on medication with mesalazine and a low-dose corticosteroid.

Investigations:

Full blood count shows a raised white cell count.

CRP is elevated.

Abdominal ultrasound reveals a thickened terminal ileum and a complex mass in the right lower quadrant.

Which is the most likely diagnosis?