Necrotizing enterocolitis, pathogenesis and the protector effect of prenatal corticosteroids

Abstract

Necrotizing enterocolitis is the most frequently occurring gastrointestinal disorder in premature neonates. Animal models of necrotizing enterocolitis and prenatal administration of cortisone have demonstrated that cortisone may accelerate maturation of the mucosal barrier, therefore reducing the incidence of this gastrointestinal disorder. The authors present a review of the literature of the most important risk factors associated with necrotizing enterocolitis, such as inflammatory gastrointestinal mediators, enteral feeding and bacterial colonization, and immaturity of the gastrointestinal barrier, and we emphasize the necessity for additional studies to explore the prenatal administration of cortisone as a preventive strategy for necrotizing enterocolitis.

Necrotizing Enterocolitis: the Evidence for Use of Human Milk in Prevention and Treatment

“…Platelet-activating factor (PAF) has been indicated as an important mediator in the pathophysiology of NEC 17 acting as an inflammatory agent. Its short half-life is attributable to its rapid degradation by PAF-degrading enzyme acetylhydrolase (PAF-AH) activity, a substance that is minimally present in neonates until 6 weeks of life but is present in human milk.…”

“…24,25 In addition, neonates have decreased pancreatic enzymes and gastric acid production in the first month of life. 17 Gastric acid is the body's first line of defense against bacteria entering enterally, and pancreatic enzymes break down proteins. Because bacterial toxins are proteins, the neonate is susceptible to any proteins remaining intact.…”

“…Long-term consequences include feeding intolerance and obstructions, short gut syndrome, and adhesions. 17 There are no proven methods for prevention of NEC; however, early recognition and medical intervention can often minimize the impact of this disease. 3 …”

Decreasing incidence of neonatal nosocomial bloodstream infections in a neonatal intensive care unit: antenatal corticosteroid treatment an innocent bystander?

“…We suggest that antenatal steroids not only improve the maturation of the respiratory tract but also the mucosal barrier of the gastrointestinal tract and therefore decrease the need for neonatal intervention (e.g. ventilation, parenteral nutrition and central venous catheters) and thus putting them at decreased risk of NBSI [23]. However, animal studies have shown that maternal corticosteroids delay myelinisation and reduce the growth of all fetal brain areas, particularly the hippocampus [28].…”

Suplementação enteral e parenteral com glutamina em neonatos pré-termo e com baixo peso ao nascer

“…Esse fato é de extrema importância, uma vez que, em bebês PT, a resposta inflamatória exacerbada do epitélio intestinal, após colonização bacteriana, pode levar ao aumento da expressão de mediadores pró-inflamatórios como a interleucina (IL)-8, que estimula a migração de leucócitos polimorfonucleares, na fase inicial da inflamação, o que, ao longo do tempo, pode levar à lesão tecidual local e também de outros órgãos (De Dooy, Mahieu, Van Bever, 2001). Há evidências de que a resposta inflamató-ria exacerbada está envolvida na patogênese de diversas doenças como a doença pulmonar crônica (De Dooy, Mahieu, Van Bever, 2001), a leucomalácia periventricular (Rezaie, Dean, 2002) e a EN (Precioso, Proença, 2002), que representam complicações presentes em neonatos PT.…”