The two cases presented here emphasize the difficulty in diagnosing NSAID-induced small bowel diaphragms and ulcers. A high degree of clinical suspicion should be maintained in the patient taking NSAIDs who presents with obscure gastrointestinal bleeding or unexplained small bowel obstruction. Routine upper and lower endoscopy should be performed in all patients with obscure gastrointestinal bleeding. If these test results are negative, then a small bowel contrast radiographic study (small bowel follow-through or enteroclysis) should be performed. However, the diagnostic yield of a small bowel series is relatively low. It has been estimated that only approximately 5% of small bowel follow-through examinations detect an intestinal bleeding site. Enteroclysis has an increased sensitivity over the standard small bowel follow-through examination, with reported yields of 10% to 25% for obscure gastrointestinal bleeding. However, entero-clysis is more time consuming, has more side effects and involves more radiation exposure than routine small bowel series. Therefore, many experts still recommend small bowel follow-through examinations as the initial test of choice for suspected small bowel lesions, with enteroclysis reserved for difficult diagnostic dilemmas.
Small bowel enteroscopy has been shown to have a greater yield than barium studies in patients with obscure gastrointestinal bleeding. Reported yields for push enteroscopy when evaluating patients with obscure gastrointestinal bleeding have varied from 13% to 64%. However, current technology limits the depth of insertion of push enteroscopy. Therefore, enteroclysis is often added to the evaluation of the patient with suspected small bowel lesions. If all of the aforementioned studies are negative and the patient continues to experience symptoms from suspected NSAID-related small bowel lesions, operative intervention is often necessary. However, as demonstrated in the present cases, small bowel diaphragms and ulcerations can be quite subtle and frequently overlooked during a routine external evaluation of the small bowel at operation. Intraoperative enteroscopy, considered to be the ultimate diagnostic procedure for complete evaluation of the small bowel, should be considered whenever the other methods of investigation fail to uncover an etiology for a suspected small bowel lesion that results in transfusion-dependent gastrointestinal bleeding or recurrent obstruction. In the future, virtual enteroscopy (computed tomography or magnetic resonance imaging) or wireless endoscopy may allow less invasive and more accurate evaluation of the small intestine.