About 1 in 1,840 babies is born with atresia of the gastrointestinal tract—lacking a functional opening in a section of the duodenum (connection between the stomach and intestine), small intestine, large intestine (colon and rectum) or anus (including imperforate anus, absence of the anal opening).
DEVELOPMENT AND TREATMENT
Scientists believe atresias can arise in various ways. The digestive tube may develop improperly, particularly in duodenal and anal atresias. Or interrupted blood supply can damage an otherwise normal bowel—this mechanism is suspected in many cases of intestinal atresia.
Surgery is needed soon after birth to connect the working segments of the intestine and/or create an anal opening. Survival to age 1 is better with small intestine atresia (91%) than with colorectal/anal atresia (75%); most babies who die have other birth defects. The lifetime cost for medical treatment, educational services and lost productivity averages more than $123,000 for colorectal/anal atresia and $75,000 for small intestine atresia.
ASSOCIATED BIRTH DEFECTS VARY BY ATRESIA SITE
The California Birth Defects Monitoring Program studied gastrointestinal tract atresias in 1.6 million births and found:
|51% of duodenal atresia occurs in isolation, 12% of cases have other birth defects and 37% have chromosome abnormalities (all Down syndrome).|
|Small intestine atresia is much more likely to be isolated (78%); 21% have other birth defects and only 2% have chromosome abnormalities.|
|62% of colorectal atresias are isolated, 36% have other birth defects and 3% have chromosome defects.|
|Anal atresia is often accompanied by other birth defects (57%); 36% are isolated and 7% have chromosome abnormalities (most frequently Down syndrome or trisomy 18).|
|Heart defects are the most common associated birth defect, but limb defects, severe kidney problems and oral clefts are also frequently noted with intestinal tract atresias.|
|Blacks have higher rates than other races for small intestine atresia, with or without accompanying birth defects.|
|Intestinal atresias/imperforate anus follow a U-shaped maternal age distribution—with lowest rates in mothers ages 25-35—even excluding infants with trisomies. (Trisomies are known to increase with mother’s age.)|