A 24-year-old female presents to her general practitioner with a 6-month history of intermittent abdominal pain, diarrhoea, and unintentional weight loss of 5 kg. She describes the pain as crampy, predominantly in the right lower quadrant, and reports episodes of loose stools occurring 4–5 times per day, occasionally containing mucus but no visible blood. She also complains of fatigue and mouth ulcers. Her medical history is unremarkable, but she has a family history of inflammatory bowel disease (IBD) in her mother. She does not smoke and denies recent travel or antibiotic use. On examination, she appears mildly pale. Abdominal examination reveals tenderness in the right iliac fossa but no palpable masses.