Small intestinal atresia in a defined population: occurrence, prenatal diagnosis and survival

To describe the prevalence, associated anomalies, prenatal diagnosis, and survival of cases of congenital small intestinal atresia (SIA).

Data were extracted from the Northern Congenital Abnormality Survey (NorCAS) for cases delivered during 1991 to 2001.

A total of 99 cases of SIA were notified from 372 717 registered births. Twenty-five (25.8%) SIA cases were associated with a chromosomal anomaly. Of the 72 SIA cases with normal karyotype, 18 (25%) were associated with other structural anomalies. The total prevalence for all SIA cases over the 11 years was 2.66 per 10 000 registered births (95% CI 2.13, 3.18), and the livebirth prevalence was 2.37 per 10 000 livebirths (95% CI 1.88, 2.87). For jejunoileal atresia, the total prevalence increased from 0.54 per 10 000 births during 1991-1995 to 1.11 per 10 000 births during 1996-2001, and livebirth prevalence increased from 0.49 to 1.06 per 10 000 livebirths. The more proximal the lesion the prenatal diagnosis sensitivity was slightly better with 19 (44.2%) cases of duodenal atresia and 3 (42.8%) cases of jejunal atresia diagnosed prenatally by routine ultrasonography.

This population-based study of SIA has confirmed several previous findings but, by considering subtypes separately, it also suggests a trend towards an increase in the prevalence of jejunoileal atresia (JIA).