Isolated Jejunal Crohn's Disease: a challenging diagnosis

A 27-year-old Nepalese male presented with recurrent abdominal pain accompanied by a lower stool consistency over the past 2 years. These episodes occurred several times a year, lasting 1 to 2 weeks, and resolved spontaneously, after adjustment of diet and/or medication for symptomatic control (e.g., antispasmodics, probiotics). Over the last year, the patient had undergone an extensive diagnostic investigation, which revealed no alterations in the laboratory workup, abdominal scan, esophagogastroduodenoscopy, and colonoscopy, including biopsies of the duodenum, and colon, so the symptoms have been attributed to irritable bowel syndrome. However, the symptoms had become more frequent, so the patient was referred to our gastroenterology department. We repeated and extended the work-up. Laboratory investigations showed an elevated erythrocyte sedimentation rate and faecal calprotectin. The remaining laboratory as well an extensive stool workup for infection were unremarkable. Esophagogastroduodenoscopy and ileocolonoscopy were normal. Small bowel capsule endoscopy revealed jejunal mucosa with lymphangiectasias, pseudopolypoids formations and superficial longitudinal ulcers, these findings were corroborated by the double-balloon enteroscopy, and biopsies showed marked architectural distortion, chronic inflammatory infiltrate, and an epithelioid granuloma. The clinical, endoscopic, biochemical, and histological findings were consistent with isolated jejunal Crohn's disease. The patient started adalimumab with complete remission after one year. We present this case given its exuberant endoscopic findings and due to the difficulty in making the diagnosis due to its rarity, location, and unspecific presentation.