Failure of complete urachal lumen closure causes urachal cysts or a free communication between the bladder and the urachus in which urine leaks from the umbilicus.
Histology of urachal cyst
These are lined by urothelium, cuboidal, flat or atrophic epithelia (figures 1, 2, 3). The cyst may be located at any point between the bladder and the umbilicus. The surrounding dermis or soft tissue often shows fibrosis, calcification and reactive changes (figures 1, 2, 3)
Urachal cyst pathology
Special studies for urachal cyst
None are generally needed.
Differential diagnosis of Urachal cyst pathology
Omphalomesenteric duct remnant – These patent ducts and cysts show the enteric mucosa rather than urothelial or a flat, attenuated epithelium.