Discussion:
The urachus is a fibrous residue of the allantois that connects the
bladder to the umbilicus. The involution of this structure usually
occurs after birth in the form of an obliterated fibrous cord. Urachal
cyst is a sub umbilical fluid collection due to the accumulation of
serous secretions and blood. A urachal cyst is usually diagnosed by
umbilical flow or umbilical pyogenic granuloma in newborns, and
exceptionally it may remain latent and be diagnosed in adulthood. The
persistence of this cyst can be revealed by complications like
infection, as in our case. The exploration of the urachal cyst is
essentially based on abdominopelvic ultrasound and the treatment is
based on surgical excision in order to prevent the risk of infection and
neoplastic degeneration.