Jejunal atresia is a rare autosomal recessive genetic disorder. Individuals with this disorder are born with a partial absence of the fold of the stomach membrane that connects the small intestine to the back wall of the abdomen. As a result, one of the three portions of the jejunum twists around the marginal artery of the colon and causes an atresia. Symptoms in this disorder include vomiting, a swollen abdomen, and constipation. Jejunal atresia may be classified into 5 types according to anatomic appearance: type I (mucosal web), type II (ends separated by a fibrous cord), type IIIa (ends separated by a V-shaped mesenteric defect), type IIIb ('apple peel' deformity), and type IV (multiple atresias). Type IIIb most commonly shows familial occurrence, although familial cases of types I, II, and IV have also been observed.
Worldwide data on the incidence of jejunal atresia is not available. However, the incidence of jejunal atresia at birth in The Netherlands is estimated to be 1 in 14,000.