Utility of gastrointestinal fluoroscopic studies in detecting stricture after neonatal necrotizing enterocolitis.

Objectives: We report our institution's 5-year experience with upper gastrointestinal study with small bowel follow-through (UGI-SBFT) and contrast enema (CE) for the diagnosis of a post-necrotizing enterocolitis (NEC) stricture. We hypothesized that sensitivity and specificity of UGI-SBFT and CE were <85% in diagnosing a post-NEC stricture. Methods: A retrospective observational cohort study was performed. Included patients were neonates diagnosed as having Bell's modified stage 2 or 3 NEC who had undergone UGI-SBFT and/or CE to evaluate for a stricture. Exploratory laparotomy was used to definitively determine the stricture presence, which was confirmed by pathology. An infant was categorized as having no stricture if no surgical intervention occurred or if no stricture was reported on pathology following surgical resection. Results: A total of 56 patients met inclusion criteria, with 51 UGI-SBFT and 85 CE performed. A total of 25 patients were diagnosed as having a stricture. For small bowel (SB) strictures, CE compared with UGI-SBFT has a higher sensitivity (0.667 vs 0.00) and a similar specificity (0.857 vs 0.833). For SB and/or colonic strictures, CE has a sensitivity of 0.667 and a specificity of 0.951. Strictures were more likely to be found on imaging in symptomatic infants compared with those in asymptomatic infants (28% vs 8%, P = 0.002). Conclusions: CE should be the initial study in the diagnostic workup for a post-NEC stricture because this test has a higher likelihood of detecting a stricture if it is present. As a result of low sensitivity of UGI-SBFT and/or CE in the diagnosis of a post-NEC stricture, a negative study should not rule out the diagnosis of a stricture in persistently symptomatic patients.