Rare presentation of urachal remnant with suprapubic sinus: A case report

Abstract

Incomplete obliteration of the allantois during development gives rise to urachal remnants. Presentation is variable and can range from draining umbilicus to chronic granuloma to acute infection requiring management with antibiotics and surgical excision. High index of suspicion is required to diagnoses more unusual presentations. This is a report on a case of urachal remnant presenting as a suprapubic sinus in a pediatric patient.

Highlights

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Urachal remnants can have variable presentations in pediatric patients.
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Presentation and diagnosis are often delayed and require a high index of suspicion.
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Staged approach to excision of infected urachal remnants is associated with good outcomes.

1 Introduction

Urachal remnant is a congenital anomaly caused by a failure in the obliteration of the allantois into the median umbilical ligament. Failure of urachal obliteration can occur at different levels leading to a variety of clinical presentations. Urachal remnants can be asymptomatic or can present with a draining umbilicus or infected urachal cyst. Given the wide variety of symptoms, diagnosis and management are often delayed and varied between centers and providers.

2 Case presentation

A 4-year-old female patient presented to the emergency room with two days of abdominal pain and constipation without associated nausea, vomiting, or fevers. Ultrasound was performed and was interpreted as suspect appendicitis with noncompressible, enlarged, tubular structure ( Fig. 1 a–b). Urinalysis at that time showed moderate leukocyte esterase and 3+ bacteria per high power field with negative culture. She had a normal white blood cell count without left shift and unremarkable chemistries. On further interview, patient was noted to have a small wound or sinus in the suprapubic region. This had been present since birth and at time of presentation to emergency room, was noted to have new onset purulent drainage. Given concern for acute appendicitis, patient was taken to the operating room for diagnostic laparoscopy and appendectomy. Appendix appeared mildly inflamed and patient was noted to have a rounded, erythematous structure at the dome of the bladder concerning for infected urachal remnant ( Fig. 2 ). A probe was inserted into the sinus tract ( Fig. 3 ) but could not be clearly visualized by laparoscopy. The appendix was removed, and patient was kept on antibiotics for a total of 7 days post operatively.

A repeat ultrasound was performed approximately four weeks after surgery and demonstrated a linear tract extending from the bladder dome cranially consistent with a urachal remnant. Of note, this could not be followed to the umbilicus and there was no associated fluid collection. She was taken back to the OR seven weeks after initial operation and was found to have long tubular structure extending from the dome of the bladder to the suprapubic sinus, consistent with a urachal remnant ( Fig. 4 a). There was no extension towards the umbilicus and previously seen inflammation and abscess was resolved. Appendiceal stump was unremarkable. Procedure was performed using the same infraumbilical incision and right and left upper quadrant working ports. The urachal remnant was dissected using a combination of blunt and cautery dissection ( Fig. 4 b). Once isolated to the level of suprapubic sinus a lacrimal duct probe was inserted in attempt to cannulate the tract. This could only be passed to the level of the fascia consistent with a partially obliterated remnant and no ongoing drainage. The remnant was divided at the level of the abdominal wall and transected at the bladder using two absorbable braided endo-loops ( Fig. 4 c). The bladder was instilled with methylene blue and saline and there was no evidence leak ( Fig. 4 d). An elliptical incision was made around the suprapubic sinus tract, and this was excised to the level of the fascia. Foley catheter was removed post operatively and patient was discharged home the same day and has recovered without complication.