HIV exposure does not worsen outcome in stage III necrotizing enterocolitis with current treatment protocols

Outcomes of Neonates Requiring Neonatal Intensive Care Admission for Necrotizing Enterocolitis in a Resource-Restricted Hospital in Cape Town, South Africa

AIM

The aim of this study is to describe the 30-day mortality, neurodevelopmental outcome and composite outcome (mortality or abnormal neurodevelopmental outcome) of neonates with necrotizing enterocolitis (NEC), requiring neonatal intensive care (NICU) admission, in a resource-restricted environment.

METHODS

All neonates admitted to Tygerberg Hospital, NICU, with a presumptive diagnosis of NEC Bell stage IIB or more, over a 5-year period, were included.

RESULTS

One hundred and thirty-five neonates were included with a mean gestational age of 29 ± 2.7 weeks and mean birth weight of 1185 g ± 446 g. The 30-day mortality was 52%, neurodevelopment abnormalities occurred in 35% of survivors and adverse composite outcome in 63%. The 30-day mortality and adverse composite outcome risk were increased by small for gestational age, shock, metabolic acidosis, inotrope requirement and first feed >9 days after surgery.

CONCLUSION

In resource-restricted environments, mortality and abnormal neurodevelopmental outcome of neonates with NEC, remain high. However, outcomes are comparable with international literature. Neonates with NEC, requiring NICU admission and surgery, require neurodevelopmental follow-up.

Probiotics Reduce Necrotizing Enterocolitis Severity in HIV-exposed Premature Infants

OBJECTIVE

To assess the effect of probiotics on the incidence of necrotizing enterocolitis (NEC) in premature infants born to human immunodeficiency virus (HIV)-positive and HIV-negative women.

PATIENTS AND METHODS

HIV-exposed and HIV-unexposed premature infants were randomized to either the probiotic or the placebo group. The probiotic consisted of 1 × 10(9) colony-forming units, Lactobacillus rhamnosus GG and Bifidobacterium infantis per day.

RESULTS

In total, 74 HIV-exposed and 110 HIV-unexposed infants were enrolled and randomized. The incidence of death [4 (5.4%) vs. 7 (6%); p = 0.79] and NEC [4 (5%) vs. 5 (5%); p = 0.76] did not differ significantly between the HIV-exposed and HIV-unexposed groups. A significant difference was found for total NEC incidence between the study and control groups [3 (3%) vs. 6 (6%); p = 0.029]. The incidence of NEC in the HIV-exposed group differed significantly [Bells I 2 (5%) vs. Bells III 2 (5%); p = 0.045).

CONCLUSION

Probiotic supplementation reduced the incidence of NEC in the premature very low birth weight infants; however, results failed to show a lower incidence of NEC in HIV-exposed premature infants. A reduction in the severity of disease was found in the HIV-exposed study group.

Human milk oligosaccharides differ between HIV-infected and HIV-uninfected mothers and are related to necrotizing enterocolitis incidence in their preterm very-low-birth-weight infants

The heavy burden of maternal HIV infection has resulted in a high prevalence of premature birth and associated necrotizing enterocolitis (NEC). Human milk oligosaccharides (HMOs) were recently associated with HIV infection and transmission through breastfeeding and were also shown to reduce NEC in an animal model, particularly the HMO disialyllacto-N-tetraose (DSLNT). The primary aim of this study was to verify differences in HMO composition between HIV-infected and HIV-uninfected women. The secondary aim was to assess whether the HMO composition in the milk of mothers whose infants were diagnosed with NEC differs from that of mothers whose infants did not develop NEC. This study forms part of a larger clinical trial conducted at the Tygerberg Children's Hospital, Cape Town, South Africa, which recruited HIV-infected and HIV-uninfected mothers and their preterm infants (<34 wk gestation; ≥500 and ≤1250 g). Eighty-two mother-infant pairs were selected for the substudy. Mother-infant pairs were stratified according to the mother's HIV (infected/uninfected) and secretor status (secretor/nonsecretor). HMOs in 4- and 28-d postpartum milk samples were analyzed by HPLC and compared between groups. Our results confirm previous reports that HIV-infected mothers have higher relative abundances of 3'-sialyllactose in their milk compared with HIV-uninfected mothers (10.7% vs. 6.8%; P < 0.01). Most intriguingly, the data also indicated that low concentrations of DSLNT in the 4-d milk samples in the mother's milk increased the infant's risk of NEC (200 ± 126 vs. 345 ± 186 μg/mL; P < 0.05), which is in accordance with results from previously published animal studies and warrants further investigation. This trial was registered at clinicaltrials.gov as NCT01868737.

Risk factors for necrotising enterocolitis in an HIV-endemic region

BACKGROUND

Several risk factors have been implicated in the development of necrotising enterocolitis (NEC). However, little has been reported on the risk factors for NEC in infants born in a setting where exposure to maternal human immunodeficiency virus (HIV) is prevalent.

OBJECTIVES

To determine maternal and infant characteristics associated with NEC in a setting with a high prevalence of HIV infection and to compare clinical presentation and mortality of NEC in HIV-exposed and unexposed infants.

METHODS

This was a retrospective, case-control study. Infants with a confirmed diagnosis of NEC, admitted between January 2005 and December 2008 were identified as cases. Two controls for each case were selected by matching them for birthweight, gestational age and date of birth. Hospital records were reviewed for maternal and infant characteristics.

RESULTS

One hundred and ten infants with confirmed NEC were identified and 220 were selected as controls. Median birthweight and gestational age were similar between cases and controls, (1370 and 1380 g, P = 0·96, and 31 weeks each, P = 0·62, respectively). Lack of use of antenatal corticosteroids (ANS) (OR 2·77, 95% CI 1·42-5·38, P = 0·003), presence of chorio-amnionitis (OR 7·28, 95% CI 2·16-24·51, P = 0·001) and not mechanically ventilated at birth (OR 3·54, 95% CI 1·29-9·69, P = 0·01) were independently associated with NEC. Maternal HIV status was not associated with NEC. Clinical presentation and mortality from NEC were similar between HIV-exposed and unexposed infants.

CONCLUSIONS

Infants who develop NEC were less likely to have received mechanical ventilation at birth, suggesting that they were less critically ill when born. Use of ANS should be encouraged as it is protective against NEC. Infants born to HIV-infected mothers were not at increased risk of NEC.

Necrotizing enterocolitis and the placenta - a key etiological link

AIM

Necrotizing enterocolitis (NEC) is the most common and severe acquired acute neonatal surgical condition, associated with premature neonates. Antenatal factors (e.g. vascular insufficiency and antenatal infections) may be important factors in "priming" the inflammatory cascade, thus predisposing to the disease. This study explores the role of placental pathology in predisposing to NEC pathogenesis.

METHODS

5338 placentas of high risk pregnancies were evaluated for placental insufficiency, infarction, and evidence of antenatal infection. Placentas of 72 premature infants developing surgical NEC (2007-2011) were identified as a separate study group and pathological placental features compared with unaffected infants.

RESULTS

Placentas of 72 of the 134 infants with surgically treated NEC (>grade 2 Bells) were available for pathologic evaluation (the remainder having been referred from other delivery units). Placentas of surgical NEC cases had significantly more evidence of noteworthy vascular pathology (placental infarcts) than high risk cases [n=38 (54.5%) versus n=1122 (21%); P<0.01]. Evidence of placental infection/chorioamnionitis or villitis plus evidence of foetal inflammatory response was present in surgical NEC infants versus unaffected infants [n=22 (31.8%) versus n=647 (12%); P<0.01], suggesting a possible pathogenic role.

CONCLUSION

This study suggests that exposure to antenatal placental infection may contribute to pathogenesis of NEC by modifying foetal vascular response and warrants further study.