Abscess formation as a complication of a ruptured urachal cyst.

The urachus is a midline tubular structure that extends upward from the dome of the bladder toward the umbilicus. This tubular structure normally involutes before birth, remaining as a fibrous band with no known function. Persistence of all or any portion of the fetal urachus results in several anomalies, the most common of which is the urachal cyst (Yu JS, Kim KW, Lee HJ, Lee YJ, Yoon CS, Kim MJ, Radiographics, 21:451-4611, 2001; Ohgaki M, Higuchi A, Chou H, Takashina K, Kawakami S, Fujita Y, Hagiwara A, Yamagishi H, Surg Today, 33:75-77, 2003). Although most urachal cysts are asymptomatic, there are a few reports about intraperitoneal rupture of infected urachal cysts, all of which caused peritonitis and sepsis (Ohgaki M, Higuchi A, Chou H, Takashina K, Kawakami S, Fujita Y, Hagiwara A, Yamagishi H, Surg Today, 33:75-77, 2003; Kojima Y, Miyake O, Taniwaki H, Morimoto A, Takahashi S, Fujiwara I, Int J Urol, 10:174-176, 2003; Agatstein EH, Stabile BE, Arch Surg, 119:1269-1273, 1984). We report the imaging and operative findings of a patient, presented with a urachal abscess after a spontaneously ruptured urachal cyst.