Etiology and prognostic factors of necrotizing enterocolitis in infants after neonatal period with hematochezia / 中国小儿急救医学

ABSTRACT

Objective:To analyze the etiology and prognostic factors of necrotizing enterocolitis(NEC) in infants after neonatal period with hematochezia.Methods:The clinical data of 62 infants older than 28 days with NEC and hematochezia diagnosed at Beijing Children′s Hospital, Capital Medical University from January 2016 to December 2021 were retrospectively analyzed, summarizing the etiology of NEC in this age group and analyze the factors affecting the prognosis of NEC.According to IgE detection results of food allergens, the infants were divided into milk protein positive group and milk protein negative group.According to the absolute value level of peripheral blood eosinophils, they were divided into increased eosinophils group(≥0.5×10 9/L) and normal eosinophils group(<0.5×10 9/L). They were divided into three groups according to co-infection NEC group(no co-infection), NEC+ clostridium difficile associated diarrhea(CDAD) group, and NEC+ other infection group(salmonella infection or sepsis). According to different feeding methods, they were divided into normal amino acid group(osmotic pressure 310 mOsm/L), diluted amino acid group(osmotic pressure 233 mOsm/L), and deep hydrolysis group(osmotic pressure 185 mOsm/L). The relief time of clinical symptoms, the recovery time of intestinal gas accumulation, feeding time to achieve physiological requirements, and the length of hospital stay in each group were compared. Results:Among 62 cases, there were 27 males and 35 females.The median age of onset was 1.4(1.2, 2.3) months.The median birth weight was 3.2(2.9, 3.4)kg.Full-term infants accounted for 87.1%.Cesarean accounted for 62.9%.Fifty-three patients(85.5%)had allergic symptoms.Thirteen patients(21.0%)had family history of allergy.Cow milk protein allergy was diagnosed in 29 cases.Thirty-two cases(51.6%) had elevated peripheral blood eosinophils.The hospitalization time of milk protein positive group was longer than that of negative group( P=0.047). The clinical remission rate after hypoallergenic formula feeding for 1 day of increased eosinophils group was higher than that of normal eosinophil group(100.0% vs.65.0%, P=0.002). Ten patients(16.1%)were complicated with clostridium difficile infection, two patients(3.2%) with salmonella enteritis, and four patients(6.5%) with sepsis.Both the hospital stay and feeding time to achieve physiological requirements of NEC+ other infection group were longer than the other two groups( P<0.05). NEC+ CDAD group had a higher rate of repeated hospitalizations(40.0%, P=0.004). The mean recovery time of intestinal gas accumulation was(4.5±2.9)days.After(3.9±3.0)days, hypoallergenic formula feeding started.After one day of feeding, the clinical remission rate was 79.0%.The average time to achieve physiological requirements was(5.8±3.2)days.The clinical symptom relief time of diluted amino acid group was shorter( P=0.006), but there was no statistical difference in feeding time to achieve physiological requirements and hospitalization time between each group( P>0.05). Conclusion:Cow′s milk protein allergy and infection(especially CDAD)are closely related to the occurrence and development of NEC after neonatal period with hematochezia.The administration of diluted amino acid-based formulae close to the osmotic pressure of breast milk and targeted anti-infective therapy could shorten the clinical remission time of NEC and reduce the risk of repeated hospitalization.