Neonates with CHD are at increased risk of developing necrotising enterocolitis due to mesenteric hypoperfusion. Necrotising enterocolitis results in repeated feed interruptions contributing to poor growth during the early post-operative phase. Poor weight gain and longer hospital stay are risk factors for death in neonates with CHD. Abdominal radiography is used as a diagnostic tool for necrotising enterocolitis; however, its utility is limited in the early stages of necrotising enterocolitis when pneumatosis intestinalis is absent. Calprotectin is a neutrophil activation biomarker, and elevated levels are evident in inflammatory diseases such as necrotising enterocolitis. The aim of this study was to determine whether there is a correlation between faecal calprotectin concentration and gut inflammation in neonates with CHD. This prospective single-centre study recruited newly diagnosed term patients with duct-dependent CHD between March 2018 and March 2019. Faecal calprotectin concentrations were measured in post-surgical patients using enzyme-linked immunosorbent assay methods. A total of 30 patients were included in the analysis. Calprotectin concentration for patients who developed necrotising enterocolitis was 3528 µg/g compared with 390 µg/g without, compared with 1339 µg/g in patients with suspected necrotising enterocolitis (p = 0.0001). Patients with suspected necrotising enterocolitis had a significantly longer length of hospital stay, on average 18 days longer compared to patients without necrotising enterocolitis (p = 0.03). Faecal calprotectin concentrations may reflect severity of gut inflammation in neonates with CHD. Suspected necrotising enterocolitis contributes to longer days nil by mouth and an increase in length of hospital stay.

Infants with CHD are at increased risk of necrotising enterocolitis, which can interfere with the achievement of adequate nutrition and, ultimately, growth and development. Necrotising enterocolitis is classified by severity as suspected, confirmed, and advanced. We sought to quantify the incidence of all types of necrotising enterocolitis among infants who underwent surgery, with a particular focus on suspected necrotising enterocolitis. This is a retrospective review of all infants <6 months of age who underwent cardiac surgery during 2012 and 2013 at Children’s Hospital Colorado. We examined the hospital course of 265 hospitalisations (n=251 patients) and found 18 patients (19 hospitalisations) with suspected necrotising enterocolitis and 16 patients (16 hospitalisations) with confirmed or advanced necrotising enterocolitis. Single-ventricle physiology, lower weight, and younger age were associated with necrotising enterocolitis. Patients with all types of necrotising enterocolitis experienced prolonged length of hospital stay. We found suspected necrotising enterocolitis to be as common as confirmed necrotising enterocolitis, and it frequently occurred early in the post-operative course. We speculate that suspected necrotising enterocolitis may often be overlooked in research owing to a reliance on billing codes. Nevertheless, suspected necrotising enterocolitis poses a substantial barrier to post-operative progression of the CHD patient, as does confirmed necrotising enterocolitis. Following the diagnosis of all types of necrotising enterocolitis, there was wide variability in practice patterns. In response to this variability, we developed care guidelines for the diagnosis and treatment of necrotising enterocolitis in this population.