The impact of cystic fibrosis on neonatal intestinal obstruction: the need for prenatal/neonatal screening.

To determine the incidence of cystic fibrosis (CF) in neonates with intestinal obstruction (NIO) secondary to meconium ileus (MI), jejunoileal atresia (JA), meconium plug syndrome (MPS), volvulus (V), and meconium peritonitis (MP) and analyze the correlation of ultrasonographic (US) signs with CF in NIO with a prenatal diagnosis of intestinal anomaly, a prospective analysis of different types of NIO from 1990 to 1998 was undertaken. Immunoreactive trypsin measurement, genetic studies, and sweat tests were performed to confirm or rule out CF. Cases with prenatal diagnosis were analyzed for gestational age, dilated bowel, ascites, hyperechoic bowel, and calcifications. Of 80 neonates, 19 (24%) had CF: 2/33 (6%) JA, 6/14 (43%) MPS, 1/14 (7.1%) MP, 10/10 (100%) MI, and 0/9 V. Thirty (37.5%) had a prenatal diagnosis of an intestinal anomaly. The overall incidence of CF in NIO with a prenatal diagnosis of intestinal anomaly was 4/30 (13%), or 333 times the estimated risk of CF in the general population. A hyperechoic pattern with dilated bowel was associated with higher specificity for CF: 3/3 cases (100%), followed by hyperechoic bowel with ascites: 3/4 cases (75%). All babies with any type of NIO should thus be screened for CF. Prenatal screening for CF should be indicated in all pregnancies with US patterns of specific intestinal disorders.