Diseases of the urachus are uncommon clinical entities, evidenced by the relatively small number of case reports in the literature. Since 1550 approximately 400 cases of urachal disease have been reported, of which more than 200 were of infections. However, many of these cases are poorly documented or unproved. Thus, in his recent review, Sterling4 was able to collect only 26 proved cases of infected urachal cyst with onset of symptoms after the age of 5 years. It is the purpose of the present paper to review the embryology, pathogenesis, and clinical features of infected urachus cysts and to add six cases to the literature.
In order to achieve adequate insight into urachal disease, brief reference must be made to the embryology of this structure. Begg1,2 has demonstrated that the urachus is not the remnant of the allantoic stalk, as was formerly believed, but, rather, is derived