The effect of gestational age on clinical and radiological presentation of necrotizing enterocolitis.

BACKGROUND/PURPOSE: To test the hypothesis that clinical and radiological features of necrotizing enterocolitis vary with gestational age in all neonates with NEC and in subgroup of surgically treated patients.

METHODS: This was a retrospective study case series. NEC cases treated in Stockholm County from 2009 to 2014 were identified in the National Quality Register. Patients were included in the study if they had a verified NEC diagnosis and they were divided into 2 groups according to the gestational age.

RESULTS: A total of 89 patients were included. Of these 60 (67.4%) neonates had a gestational age <28 and 29 (32.6%) infants ≥28weeks. Surgical NEC patients were 57 (64%). Pneumatosis intestinalis at the abdominal radiographs was noted significantly more often in neonates born at ≥28weeks of gestation (86.2%) compared to extremely preterm newborns (60.0%). Neonates born at ≥28weeks of gestation presented more often bloody stools (58.6%) compared to extremely preterm newborns (20.0%). In surgical NEC patients gasless abdomen was detected in 35.6% of the neonates born <28weeks compared to 6.7% of the more mature neonates.

CONCLUSIONS: Extremely preterm neonates with NEC show less specific clinical and radiological signs of NEC compared to more mature neonates. This suggests that Bell's classification is not adequate for the diagnosis and staging of NEC in extremely preterm neonates.

LEVEL OF EVIDENCE: III.