Pathogenesis of choledochal cyst

Abstract

The well-known observation that females have a much higher incidence of choledochal cysts than males suggests that this may be a sex-linked hereditary disease. However, up to now there have been no familial case reports in the literature. The author describes a sex-linked familial case. Both, the mother and her single daughter suffered from a type I choledochal cyst with a narrow segment and amylase-negative bilious fluid in the cyst. In order to lend support to the plausibility of a hereditary disease, blood types, histocompatibility, and chromosome status were investigated. Although their blood type was the same (A₁ positive) and histocompatibility antigens were only slightly different, we could not detect a chromosomal defect in either mother or child and could not find any association with other malformations. Despite these implications against the possibility of a hereditary disease, it should be noted that in both patients the nature of the choledochal malformation was the same, especially with regard to the spastic inferior choledochal sphincter (= narrow segment) and the amylase-negative bile. Regarding the forms of choledochal dilatation, the author presumes that types I, IV, and V have a different pathogenesis than types II and III.