Urachal cyst pathology

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)

Figure 1 

Figure 2 

Figure 3 

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.