Case 2: A 49-year-old man was referred to the authors’ institution for evaluation of recurrent small bowel obstruction. He reported a total of 26 episodes of partial small bowel obstruction that had responded to conservative treatment over the previous six to seven years. He underwent exploratory laparotomy two years previously with no source of obstruction found, but the jejunum was noted to have an area of active inflammation, and a local reactive mesenteric lymph node was excised. He subsequently underwent an EGD, which revealed a fairly tight postbulbar duodenal stricture that was twice dilated with a balloon dilator to 54 French with good endoscopic results. However, the patient continued to have recurrent episodes of partial small bowel obstruction. Before referral, he underwent a repeat upper endoscopy with a pediatric colonoscope that revealed a widely patent duodenum with no evidence of stricture recurrence and normal findings into the proximal jejunum. In addition, a small bowel follow-through showed no abnormalities. His medical history was significant for an appendectomy as a teenager, rotator cuff injury with arthroscopic surgery two years prior and a motorcycle accident five years prior. He had been using NSAIDs regularly for at least 25 years for various orthopedic injuries. He had been off all NSAIDs for about eight months. He was then referred to the authors’ institution, where he initially underwent a push enteroscopy that was normal to approximately 120 cm beyond the ligament of Treitz. He then underwent an intraoperative enteroscopy that revealed a discrete diaphragm-like stricture approximately 5 mm in diameter in the distal jejunum with an associated ulceration at one border (Figure 2); the enteroscope could not be passed through this stricture. Two other discrete areas of fibrotic-appearing small bowel were noted on external examination. A 30 cm segment of small bowel containing all three areas was resected. The remainder of the small bowel appeared normal. Pathological examination revealed that the area of stricture in the proximal jejunum seen endoscopically contained three successive plicae circulares fused into a thickened circumferential ring covered with granular-appearing mucosa with focal erosion, consistent with an NSAID-induced mucosal diaphragm (Figure 3). In addition, four small (less than 0.8 cm in diameter), nonobstructing carcinoid tumours were noted in the resected specimen extending through the muscularis propria; all seven lymph nodes were negative for tumour. Two of these tumours were associated with the more distal fibrotic areas palpated by the surgeons. One tumour was near but not involving the mucosal diaphragm. There have been no further bouts of intestinal obstruction at a four-month follow-up.
Figure 2) Endoscopic view of nonsteroidal anti-inflammatory drug-induced small bowel diaphragm in distal jejunum
Figure 3) Top Low power photomicrograph of a mucosal diaphragm formed by fusion of several plicae circulares (hemotoxylin and eosin stain, original magnification x10). Bottom Additional section showing focal erosion of mucosa (hemotoxylin and eosin stain, original magnification X12.5)