A Study of Histopathological Findings in Neonatal Necrotizing Enterocolitis in Early and Late Term Infants

BACKGROUND Neonatal necrotising enterocolitis (NNEC) is very common among premature infants. However, its incidence in term babies has also been on the rise. It is a potentially devastating condition with variable mortality. The diagnosis and management of NNEC is clinically supported by modified Bell’s grading. In cases where surgical resection of bowel is performed, histological findings are rarely given much importance. In this study, we have studied the histopathology of resected bowel in NNEC in term babies and correlated these findings with the age of the neonate and also with modified Bell’s grading. METHODS 25 cases of small bowel specimens of term infants received at the pathology department of a tertiary paediatric referral hospital were studied in detail for gross and microscopic features. The histological parameters considered were transmural coagulative necrosis, granulation tissue, crypt distortion, pseudomembrane formation, villous atrophy and pneumatosis intestinalis. These findings were compared with the age of the neonates and also correlated with the modified Bell’s grading. The clinical presentation and histology were also compared in early presenting term neonates less than a week in age and term infants of more than a week. RESULTS We found early neonates of age less than a week to have higher Bell’s grading and more severe histology. CONCLUSIONS Term neonates also present with severe NNEC, requiring surgical resection of the bowel. Early presentation and higher Bell’s grading are associated with more severe histopathological changes. KEYWORDS NNEC, Term Neonates, Bell’s Grading, Histopathology

Incidence of neonatal necrotising enterocolitis in high-income countries: a systematic review

ObjectiveTo conduct a systematic review of neonatal necrotising enterocolitis (NEC) rates in high-income countries published in peer-reviewed journals.MethodsWe searched MEDLINE, Embase and PubMed databases for observational studies published in peer-reviewed journals. We selected studies reporting national, regional or multicentre rates of NEC in 34 Organisation for Economic Co-operation and Development countries. Two investigators independently screened studies against predetermined criteria. For included studies, we extracted country, year of publication in peer-reviewed journal, study time period, study population inclusion and exclusion criteria, case definition, gestation or birth weight-specific NEC and mortality rates.ResultsOf the 1888 references identified, 120 full manuscripts were reviewed, 33 studies met inclusion criteria, 14 studies with the most recent data from 12 countries were included in the final analysis. We identified an almost fourfold difference, from 2% to 7%, in the rate of NEC among babies born <32 weeks’ gestation and an almost fivefold difference, from 5% to 22%, among those with a birth weight <1000 g but few studies covered the entire at-risk population. The most commonly applied definition was Bell’s stage ≥2, which was used in seven studies. Other definitions included Bell’s stage 1–3, definitions from the Centers for Disease Control and Prevention, International Classification for Diseases and combinations of clinical and radiological signs as specified by study authors.ConclusionThe reasons for international variation in NEC incidence are an important area for future research. Reliable inferences require clarity in defining population coverage and consistency in the case definition applied.PROSPERO International prospective register of systematic reviews registration numberCRD42015030046.