a 30year  old man presented to the outpatient clinic with abdominal pain and a purulent , cheesy discharge from the umbilicus which lasted for a few days . the ultrasound scan suggested the presence of an abscess within the abdominal anterior wall . a ct scan ( figure 1 ) confirmed the presence of an infected cyst in the midline of the abdominal wall , with no communication with the bladder . during laparotomy , a urachal cyst with the cuff of the bladder dome were removed ( figure 2 ) . pathology revealed benign urachal cells with no signs of malignancy . the midline cyst shown at ct . the urachus is a fibrous remnant of the cloaca that in adults connects the dome of the bladder with anterior abdominal wall . the cloaca , in the fetal life , is an extension of the urogenital sinus and allantois , and is derived from the yolk sac . after birth it obliterates , forming the median umbilical ligament . otherwise , it may present variably : a urachal cyst , a part of the urachal canal without any patent connection with the bladder or the umbilicus , a patent urachus communicating the bladder with the umbilicus , a urachal sinus which is a form of a cyst communicating with the umbilicus or a urachal diverticulum , a structure which opens within the bladder . those remnants found in neonates younger than 6 months usually resolve spontaneously without the need for surgery . those found in older patients require management because of a greater risk for infection , and of utmost importance in adults , due to an increased risk of neoplastic differentiation . the most commonly observed and managed urachal anomalies in children are : urachal cyst ( 54% ) , urachal sinus ( 30% ) , patent urachus or vesicourachal diverticulum . urachal cancer ( 51% ) and urachal cyst ( 35% ) , which is usually infected , are the most frequent modalities diagnosed in adults . some patients with urachal remnants are asymptomatic , but still carry a high risk for infection or cancer . typical clinical manifestations of patent urachal pathologies , as seen in our case , are umbilical discharge , tenderness , erythema or a mass within the umbilicus . abdominal pain can be the only symptom of disease , and can mimic an acute abdomen due to appendicitis or meckel 's diverticulum . the differential diagnosis of an umbilical mass should include hematoma , abscess , umbilical hernia , urachal carcinoma and tumors of the abdominal wall . . however , differentiation between the benign urachal remnant and urachal cancer may be difficult due to unclear contrast enhancement during ct , even though the presence of calcifications is suggestive of malignancy . sixty seven percent of adults who presented with a urachal mass at the time of diagnosis had , cancer . among them , 57% had calcifications seen on imaging [ 4 , 6 ] . ashley et al . found that patients older than 55 , who experienced an episode of hematuria , were at greatest risk of having urachal malignancy , most commonly an adenocarcinoma . in our case , there was no suspicion for malignancy due to the patients ages , negative history suggestive of malignany ( hematuria ) and ct scans . when urachal cancer can not be excluded ( hematuria and mass seen at the bladder dome on imaging ) cystoscopy with biopsy and urine cytology should not be omitted . cytology is positive in 38% of patients with urachal carcinoma and is correlated with an increased tumor grade . if urachal pathology appears with signs of infection , a two  stage treatment is recommended : initially , administration of antibiotics and resolution of inflammation , followed by surgical removal . in benign urachal anomalies , complete excision , with or without the cuff of the bladder , is sufficient . it is not necessary to remove the umbilicus . in case of urachal cancer , partial or radical cystectomy partial cystectomy with en bloc resection of the urachus with cancer within the bladder dome provides similar oncologic outcomes to radical cystectomy . the umbilicus with urachus and bladder dome are resected with large margins ( 2 cm ) of healthy tissue . it has been emphasized that the ports should be inserted 3 5 cm above and 2 cm to the left of the umbilicus to allow proper access to the operating field . the approach should be dictated by the surgeon 's preferences and experience to ensure the best possible oncologic results . often its presentation is nonspecific , and as such , may cause many diagnostic problems . although nowadays many methods are available for diagnosing pathology of urachal remnants , none of these is completely accurate .
the urachus is the remnant of the cloaca , which in adults attaches the bladder dome to the umbilicus . after birth 
 it obliterates and presents as the midline umbilical ligament . 
 patent urachal anomalies are usually detected in childhood . in adults 
 they occur very rarely and the presentation and diagnosis may be occasionally challenging . 
 we present and discuss the case of an infected urachal cyst found in a 30year  old adult .