The incidence and modifiable risk factors for necrotizing enterocolitis in preterm infants: a retrospective cohort study

Neonatal Necrotizing Enterocolitis: An Update on Pathophysiology, Treatment, and Prevention

Necrotizing enterocolitis (NEC) is a life-threatening disease predominantly affecting premature and very low birth weight infants resulting in inflammation and necrosis of the small bowel and colon and potentially leading to sepsis, peritonitis, perforation, and death. Numerous research efforts have been made to better understand, treat, and prevent NEC. This review explores a variety of factors involved in the pathogenesis of NEC (prematurity, low birth weight, lack of human breast milk exposure, alterations to the microbiota, maternal and environmental factors, and intestinal ischemia) and reports treatment modalities surrounding NEC, including pain medications and common antibiotic combinations, the rationale for these combinations, and recent antibiotic stewardship approaches surrounding NEC treatment. This review also highlights the effect of early antibiotic exposure, infections, proton pump inhibitors (PPIs), and H2 receptor antagonists on the microbiota and how these risk factors can increase the chances of NEC. Finally, modern prevention strategies including the use of human breast milk and standardized feeding regimens are discussed, as well as promising new preventative and treatment options for NEC including probiotics and stem cell therapy.

The role of nutrition in analysis of risk factors and short-term outcomes for late-onset necrotizing enterocolitis among very preterm infants: a nationwide, multicenter study in China

BACKGROUND

Necrotizing enterocolitis (NEC) is a serious gastrointestinal disease, primarily affects preterm newborns and occurs after 7 days of life (late-onset NEC, LO-NEC). Unfortunately, over the past several decades, not much progress has been made in its treatment or prevention. This study aimed to analyze the risk factors for LO-NEC, and the impact of LO-NEC on short-term outcomes in very preterm infants (VPIs) with a focus on nutrition and different onset times.

METHOD

Clinical data of VPIs were retrospectively collected from 28 hospitals in seven different regions of China from September 2019 to December 2020. A total of 2509 enrolled VPIs were divided into 2 groups: the LO-NEC group and non-LO-NEC group. The LO-NEC group was divided into 2 subgroups based on the onset time: LO-NEC occurring between 8 ~ 14d group and LO-NEC occurring after 14d group. Clinical characteristics, nutritional status, and the short-term clinical outcomes were analyzed and compared among these groups.

RESULTS

Compared with the non-LO-NEC group, the LO-NEC group had a higher proportion of anemia, blood transfusion, and invasive mechanical ventilation (IMV) treatments before NEC; the LO-NEC group infants had a longer fasting time, required longer duration to achieve the target total caloric intake (110 kcal/kg) and regain birthweight, and showed slower weight growth velocity; the cumulative dose of the medium-chain and long-chain triglyceride (MCT/LCT) emulsion intake in the first week after birth was higher and breastfeeding rate was lower. Additionally, similar results including a higher proportion of IMV, lower breastfeeding rate, more MCT/LCT emulsion intake, slower growth velocity were also found in the LO-NEC group occurring between 8 ~ 14d when compared to the LO-NEC group occurring after 14 d (all (P < 0.05). After adjustment for the confounding factors, high proportion of breastfeeding were identified as protective factors and long fasting time before NEC were identified as risk factors for LO-NEC; early feeding were identified as protective factors and low gestational age, grade III ~ IV neonatal respiratory distress syndrome (NRDS), high accumulation of the MCT/LCT emulsion in the first week were identified as risk factors for LO-NEC occurring between 8 ~ 14d. Logistic regression analysis showed that LO-NEC was a risk factor for late-onset sepsis, parenteral nutrition-associated cholestasis, metabolic bone disease of prematurity, and extrauterine growth retardation.

CONCLUSION

Actively preventing premature birth, standardizing the treatment of grade III ~ IV NRDS, and optimizing enteral and parenteral nutrition strategies may help reduce the risk of LO-NEC, especially those occurring between 8 ~ 14d, which may further ameliorate the short-term clinical outcome of VPIs.

TRIAL REGISTRATION

ChiCTR1900023418 (26/05/2019).

Neurodevelopmental impairment following surgical necrotizing enterocolitis with gestational age ≥ 28 weeks: who is at risk?

PURPOSE

Surgical necrotizing enterocolitis (NEC) is a severe medical condition that, even after surgery, a portion of the survival infants may still have neurological sequelae. The objective of this study was to identify the risk factors associated with the development of permanent neurodevelopmental impairment (NDI) in neonates with surgical NEC.

METHODS

Between January 2016 and June 2022, a retrospective data collection was conducted on 98 individuals who experienced surgical NEC with gestational age ≥ 28 weeks. Among these patients, 27 patients were diagnosed with NDI, while the remaining 71 patients did not have NDI. Based on this division, the patients were categorized into the NDI group and the Non-NDI group. Demographics, comorbidities, and admission lab results were analyzed using univariate and logistic regression analyses.

RESULTS

Of the 98 neonates following surgical NEC, 27(27.6%) developed permanent neurodevelopmental impairment (NDI). Predictors of NDI were identified through the final multivariable logistic regression analysis, which revealed that gestational age ≤ 32 weeks (p = 0.032; odds ratio [OR], 5.673), assisted mechanical ventilation after NEC onset (p = 0.047; OR, 5.299), postoperative acute kidney injury (p = 0.040; OR, 5.106), CRP day 3 after NEC onset (p = 0.049; OR, 1.037), time from presentation to surgery (p = 0.003; OR, 1.047) were significant risk factors.

CONCLUSIONS

Our study identified gestational age ≤ 32 weeks, assisted mechanical ventilation after NEC onset, postoperative acute kidney injury, CRP day 3 after NEC onset, and time from presentation to surgery as significant risk factors for NDI in neonates with surgical NEC. These factors would be helpful to refine treatment modalities for better disease outcomes. We also determined the cut-off values of CRP day 3 after NEC onset and time from presentation to surgery, allowing for the individualized evaluation of NDI risk and the implementation of earlier targeted laparotomy.

Impact of Size for Gestational Age on Multivariate Analysis of Factors Associated with Necrotizing Enterocolitis in Preterm Infants: Retrospective Cohort Study

OBJECTIVE

 Necrotizing enterocolitis (NEC) primarily affects preterm, especially small for gestational age (SGA), infants. This study was designed to (1) describe frequency and timing of NEC in SGA versus non-SGA infants and (2) assess whether NEC is independently associated with the severity of intrauterine growth failure.

STUDY DESIGN

 Retrospective cohort study of infants without severe congenital malformations born <33 weeks' gestational age (GA) carried out from 2009 to 2021. The frequency and time of NEC were compared between SGA and non-SGA infants. Multivariate logistic regression was used to assess whether NEC was independently associated with intrauterine growth restriction. Severe growth restriction was defined as birth weight Z-score <  -2.

RESULTS

 Among 2,940 infants, the frequency of NEC was higher in SGA than in non-SGA infants (25/268 [9.3%] vs. 110/2,672 [4.1%], respectively, p < 0.001). NEC developed 2 weeks later in SGA than non-SGA infants. In multivariate analysis, the adjusted odds of NEC increased with extreme prematurity (<28 weeks' GA) and with severe but not moderate growth restriction. The adjusted odds of NEC increased with urinary tract infection or sepsis within a week prior to NEC, were lower in infants fed their mother's own milk until discharge, and did not change over five epochs. NEC was independently associated with antenatal steroid (ANS) exposure in infants with birth weight (BW) Z-score < 0.

CONCLUSION

 NEC was more frequent in SGA than in non-SGA infants and developed 2 weeks later in SGA infants. NEC was independently associated with severe intrauterine growth failure and with ANS exposure in infants with BW Z-score < 0.

KEY POINTS

· We studied 2,940 infants <33 weeks' GA.. · We assessed NEC.. · NEC was more frequent in SGA infants.. · NEC occurred 2 weeks later in SGA infants.. · NEC was associated with severe growth restriction..