The urachus, also known as the median umbilical ligament, is a midline extraperitoneal tubular structure extending from the dome of the bladder to the umbilicus, bordered by the transversalis fascia anteriorly and the parietal peritoneum posteriorly [3]. Failure to involute in utero results in UAs which are seen in 2/300,000 pediatric admissions [4] with reported cases of urachal cysts, since 1882, being fewer than 200 cases among adults [5]. They are more common in males (2:1) with 10–48% for patent urachus, 31–43% for urachal cyst, 18–43% for urachal sinus, and 3–4% for urachal diverticulum [6, 7].
Urachal cysts are usually asymptomatic, unless they are large enough to cause compression symptoms, complicated by infection, rupture, or malignant transformation [8]. They present with abdominal pain, fever, lethargy, umbilical discharge, or a midline mass [5] which might drain into the urinary bladder or through the umbilicus, leading to fistula formation [9]. In complicated cases, it may lead to necrotizing fasciitis [5] or rupture inside the abdomen, causing peritonitis and sepsis [9].
Urachal remnant has been associated with other anomalies including hypospadia, meatal stenosis, vesicouretheral reflux, ureteropelvic obstruction, crossed renal ectopia, umbilical and/or inguinal hernias, cryptorchidism, anal atresia, and omphalocele as reported in the literature [10,11,12,13]. Bertozzi et al. reported inguinal hernia in 12 children that were treated between 2005 and 2013, as the most common associated anomaly (33%) [14].
UAs can be diagnosed by US. Two studies reported 12 and 27 cases of UA, in which all of their patients were diagnosed by US with limited usage of CT scans and magnetic resonance imaging (MRI) which were only used for further detailed anatomy [14, 15]. However, Widni et al. reported US as having 79% sensitivity, 30% specificity, and 83% positive predictive value in diagnosing UAs [16].
Yu et al. reported that many of the features of UA, including congenital lesions with or without superimposed infection and tumors, are well displayed at sagittal US with a CT scan to help confirm the US findings and disclose the nature and local extension of the disease as well as any systemic metastases [1].
Complete surgical excision is considered the treatment of choice, given the risk of malignant transformation and the high recurrence rate after simple drainage, which Mesrobian et al. reported at 39% [17]. The excision can be done either by an open laparoscopic approach [14, 15] or a robotic assisted laparoscopic surgery [18]. Bertozzi et al. reported 12 cases of UA that were treated by laparoscopic or laparoscopic-assisted surgery [14]. Sato et al. reported 13 patients treated by the umbilical approach and 7 patients treated by the laparoscopic approach. There was no difference between the 2 groups in operative time or hospital stay [15]. Excision can be done safely using robotic-assisted laparoscopic surgery with short hospitalization and minimum to no narcotic pain control postoperatively [18].
It should be noted that Galati et al. reported that urachal remnants in patients younger than 6 months are likely to be resolved without operative management [6]. Sato et al. recommended conservative follow-up for UA patients who are under 1 year of age unless there are repeated infections [15].
In this case, our patient had non-resolving symptoms even with empirical antibiotic treatment, and the patient was later found to have associated anomalies including a single kidney and multiple vertebral anomalies. Based on our literature review, no case has been reported to date that includes the associated anomalies.
