6go6ckt5b8|3000F7576AC3|Tab_Articles|Fulltext|0xf1ff648e07000000f903000001000100

6go6ckt5b5idvals|487

6go6ckt5b5|2000F757Tab_Articles|Fulltext

Introduction

The urachus which is a remnant of the cloaca attaches the urinary bladder dome and the umbilicus. It obliterates after birth and remains as the midline umbilical ligament. Urachal abnormalities are common in children whereas in adults they are rare and have atypical presentation.

Case Report

A 49 year old gentleman presented to the casualty with history of dull aching abdominal pain more on the suprapubic region for 7 days. It was gradual in onset. There was no aggravating or relieving factor, no radiation or shifting of pain. Pain was associated with nausea but no vomiting. He also had low grade fever for 5 days. He denied lower urinary tracts symptoms, hematuria, calcuria or prior history of similar episodes. His bowel habits were normal. He gave history of endoscopic surgery for stricture urethra about 3 years ago. General examination was normal. Systemic examination revealed a tender mass of about 10x9 cm in the suprapubic region, firm in consistency, with smooth surface and spherical in shape. The lower margin of the mass could not be felt. The differential diagnosis at this point were pyocystitis, appendicular perforation/Meckel`s diverticulitis or urachal cyst.  The laboratory tests were within normal limit. Screening ultrasound showed a well-defined heterogenous hyperechoic mass lesion  with multiple  hypoechoic areas within measuring approximately 9.5x8x5 cm  in midline extending from the dome of bladder till the infra-umbilical region. Axial contrast enhanced computerized tomography (CECT) image at the level of bladder showed  a well-defined peripherally enhancing lesion with non-enhancing necrotic central part with multiple enhancing septations within, at antero-superior part of bladder [Fig.1]. Sagittal CECT image showed a well-defined heterogenously enhancing lesion in midline antero-superior to the urinary bladder extending from the dome of bladder to the umbilicus.  The lesion measured approximately 10x8x5 cms (APxTxCC) in size. There was mild peri-lesional fat stranding and mild diffuse urinary bladder wall thickening [Fig.2]. The diagnosis of infected urachal cyst was made.


    He was taken up for surgery. Intraoperative cystoscopy showed narrowing of the anterior urethra and a normal urinary bladder with no communication with the cyst. He subsequently underwent incision and drainage of an 10x8 cm acutely inflamed cyst, nearly 100 ml of thick pus was evacuated. The pus was sent for culture & sensitivity which grew E. Coli and the patient was started on culture sensitive antibiotics. He was discharged and planned for staged excision of the cyst. Subsequently he underwent staged surgery after two weeks. Intraoperatively a 4x4 cm urachal cyst was found. This cyst was excised and sent for histopathology. The biopsy of the mass revealed chronic inflammation with no evidence of malignancy.

Discussion

The cloaca is a derivation of the yolk sac which is an extension of the urogenital sinus. During the fifth month of development the bladder descends into the fetal pelvis, pulls the urachus with it, resulting in the formation of the urachal canal. It progressively obliterates after birth and forms the median umbilical ligament. Histologically, the urachus is composed of three layers- transitional epithelium, fibro-connective tissue and outer layer of smooth muscle [1]. A urachal cyst presenting in an adult is rare as the urachus normally obliterates in early infancy. Risher et al. [2] in their review of 31 years found only 12 adults with urachal anomalies. Adults usually presents with infection of the cyst. Various organisms like E. Coli, Enterococcus  faecium, Klebsiella pneumonia, Proteus or Streptococcus viridans may be isolated. Our patient had grown E.Coli in the pus which was sent after the incision and drainage of the infected urachal cyst.

    Patients with infected urachal cyst can present with a wide range of symptoms like umbilical discharge, abdominal pain, fever and midline mass. Due to the varied presentation patients are often misdiagnosed [3]. Complications of urachal cyst can occur in the form of sepsis, fistula formation, peritoneal rupture, stone formation and neoplastic transformation [4]. Triad of symptoms including a tender infra-umbilical mass, umbilical discharge and sepsis should arouse suspicion of the diagnosis of urachal cyst. The index patient didn’t have complaints of discharging umbilicus sinus.

    Surgical intervention is the treatment of choice. Open excision has been the treatment of choice but laparoscopic surgery can be done in selective cases [5]. Some surgeons have recommended staged approach with initial incision and drainage followed later by the excision of the cyst [6]. This was done in our case.  Complete excision of the cyst wall is recommended because of the possibility of malignant transformation into adenocarcinoma [2]. The histopathology in our case was chronic inflammation with no evidence of malignancy.

Conclusion

The incidence of urachal pathology is rare in adults. An accurate history along with physical examination and guided imaging is crucial to reach a correct diagnosis.

References

1. Begg RC. The urachus: its anatomy, histology and development. Journal of Anatomy. 1930;64:170-183.
2. Risher WH, Sarda A, Bolton J. Urachal abnormalities in adults: the Ochsner experience. Southern Medical Journal. 1990;83:1036-1039.
3. Ash A, Gujral R, Raio C. Infected urachal cyst initially misdiagnosed as an incarcerated umbilical hernia. Journal of Emergency Medicine. 2012;42:171-173.
4. Ekwueme KC, Parr NJ. Infected urachal cyst in an adult: a case report and review of the literature. Cases Journal. 2009;2:6422.
5. Janes VA, Hogeman PH, Achten NB, Tytgat SH. An infected urachal cyst-a rare diagnosis in a child with acute abdominal pain. European Journal of Pediatrics. 2012;171:587-588.
6. Yoo KH, Lee SJ, Chang SG. Treatment of infected urachal cysts. Yonsei Med J. 2006;47:423-427.