Urethral duplication in a 1 year old: a rare case report

Abstract

An 8-month-old male child presented with the complaint of two separate urinary streams from the penis. The child had no complaints of incontinence or recurrent UTI (urinary tract infection). Initial diagnosis of urethrocutaneous fistula was made and proceeded to micturating cystourethrography (MCU) and found to be having a urethral duplication. The duplicated urethra was excised and accessory urethra closed. Postoperatively, the child was followed up for 1 year and had no complaints of recurrence or incontinence. Through this case report, we learn about different classification systems and types of urethral duplication and their associated anomalies, and mode of management, which is mainly surgical. Further, management should be individualised to each patient based on their complaints and intraoperative findings.

Background

Urethral duplication is a very rare congenital anomaly that is more commonly seen in boys, with very few cases reported in girls. It is a very rare anomaly with around 350 cases reported in the literature worldwide. Because of the diversity of clinical manifestations, difficulty in diagnosis and ambiguity in its classification, we present a case report and review of the literature with regard to urethral duplication and its management.

Urethral duplication is described as closely positioned two or more tracts of smooth musculature covered by the mucosal lining. The duplication can be partial or complete. It can occur in the sagittal plane as well as in the coronal plane. It can present with other congenital malformations of the gastrointestinal tract, heart, kidneys and bones.

Case presentation

An 8-month-old male child was brought to the out patient department (OPD) with complaints of a separate urethral opening with two streams of urine: one from the tip of the penis and another from the dorsal aspect of his penis from birth. The patient has no other complaints of pain or ballooning of penis at micturition, incontinence of urine, recurrent urinary tract infection (UTI) or fever. He has no history of pain associated with fistula. He has no associated abnormal bowel habits. His milestones and vaccinations are age-appropriate.

Birth history: lower segment caesarean section (LSCS) due to maternal oligohydramnios. Term baby with birth weight of 2.5 kg.

On examination: Child active and healthy.

Systemic examination: Cardiopulmonary and neurological systems were unremarkable. The penis showed an extra opening in the dorsal aspect, 1.5 cm proximal to the orthoptic position of the opening of the actual urethra (figure 1). On micturition, two streams of urine could be seen: one from the dorsal opening and another from the tip of the penis. Bilateral testes were in the scrotum, and scrotum was normal.

Figure 1.

Double meatus on inspection (arrowhead denotes accessory dorsal opening).

With this clinical picture in mind, the child was given a working diagnosis of urethrocutaneous fistula. Baseline blood investigations were done and found to be within normal limits.

Investigations

The patient underwent a routine ultrasonogram (USG) abdomen to look for any associated renal or ureteric anomalies and was found to be normal. On table MCU was performed and the patient was found to have accessory urethra (duplication) arising from near the bladder neck separate from normal urethra: Effman type II A1 and grade 2 vesicoureteric reflux. MCU is a critical investigation for identifying the urethral and bladder abnormalities in children.

This is a dynamic test that helps to detect any vesicoureteral reflux, bladder pathology, and congenital or acquired anomalies of the bladder outflow tract. This is done by passing a catheter into the bladder, then filling the bladder with contrast material and then taking serial X-ray films when the child is made to void.

Treatment

Per operative: The baby was planned for on table MCU and excision of the urethrocutaneous fistula.

MCU findings (figure 2): (1) It was found to be an accessory urethra (duplication) arising from near the bladder neck separate from normal urethra: Effman type II A1. (2) Grade 2 right vesicoureteric reflex was seen.

Figure 2.

Micturating cystourethrography findings showing two separate urethra arising from the bladder.

The baby was catheterised with an 8F feeding tube in the standard urethral opening (figure 3). Another feeding tube was passed through the dorsal meatus (figure 3). Sharp dissection was done circularly along the dorsal meatus up to the sphincter level (figures 4 and 5) to delineate the accessory urethra.

Figure 3.

Dorsal and ventral opening catheterised with feeding tube.

Figure 4.

Dorsal urethra dissected and delineated.

Figure 5.

Dorsal urethra dissected and delineated.

Accessory urethra closed at that level in two layers (figure 6). Local dartos flap cover to the exposed soft tissue (figure 7).

Figure 6.

Dorsal urethra.

Figure 7.

Local dartos flap cover.

Outcome and follow-up

The baby was discharged with a catheter on Post Operative Day (PoD) 1 and reviewed back at the OPD on PoD4 for removal. The baby voided freely without any dribble from the dorsal aspect of the penis. There was no dribbling from the previous dorsal meatus site in the later follow-up. The baby was reviewed after 1 year of surgery and was found to have a single stream of urine from the tip of the penis without any accessory opening, without any complaints during the follow-up period.

Discussion

Urethral duplication is a complex congenital anomaly, and the different manifestations and presentations are likely due to different embryological origins. Multiple theories have been suggested to clarify the mechanism of development of the urethral duplication like partial mesodermal fusion, abnormal Müllerian ducts, ischaemic insults during embryogenesis, developmental defects of the urogenital sinus and misalignment between the termination of cloacal membranes; however, the exact mechanism still remains ambiguous.¹ The presence of a second meatus or the doubt of a double urethra usually necessitates a voiding and a retrograde cystourethrogram that will aid to make appropriate diagnosis and to plan surgical repair. The duplicated urethra is typically dorsal to a normal functional urethra, potentially leading to urinary continence in the accessory urethra as the sphincteric function is intact,² as seen in this case. Here, our case is seen having a complete urethral duplication of Effman type II-A1 with associated grade 2 vesicoureteric reflux.

Classification systems for urethral duplication: Effman classification

The Effman et al³ classification system describes three types of urethral duplication that vary depending on the radiological location of the accessory urethra.

Type I shows incomplete duplication. This can be further classified into type I-A where the distal duplicated urethra open on the dorsal or ventral surface of the penis but do not communicate with the urethra or bladder. In type I-B, a proximal accessory urethra opening originating in the urethral channel ends blindly in the periurethral tissues.

In type II, there is complete duplication of urethra. This is further classified into two: A and B. Type IIA has two meatus, while type IIB has a single meatus. Type IIA is further subdivided into type IIA-1 where there are two meatus with two separate urethra originating directly from the bladder; type IIA-2 has two meatus with two urethra, but they arise from a common urethra just distal to the neck of the bladder. Another variant of the type IIA-2 is a Y-shaped variant with the accessory urethra arising from the primary urethra and coursing independently to open into the rectum. Type IIB has two urethra that arise from the bladder or posterior urethra and unite into a common channel distally. In type III, duplication is at the level of the bladder, with urethra arising from a septa or duplicate bladder (figure 8).⁴

Figure 8.

Effman’s classification of urethral duplication.⁴

In a study by Lopes et al,⁵ who reported on 13 boys with urethral duplication, they found out that the mean age of presentation was 38 months (3 years). They have observed that type IIA2 was the most common pattern (8/13 patients, 61.5%), followed by type IA (3/13 patients, 23%) and type IIA1 (2/13 patients, 15.3%). The most frequent clinical manifestations were UTI observed in 11 out of 13 patients (84.6%) and anal urinary leakage, which is found in 7 out of 13 patients (53.8%). Associated anomalies were found in 9 out of 13 patients (69.2%).

Associated anomalies like urethral duplication include bifid scrotum, cryptorchidism, hypospadias, megalourethra, micropenis, vesicoureteral reflux, agenesis and renal ectopy, dysplastic-multicystic kidney, vertebral anomalies (sacral agenesis, thoracic hemivertebra) and anorectal anomalies.

In our case, the child presented at 8 months of age with double urinary stream, no incontinence or recurrent UTI, and had an associated right-sided grade 2 vesicoureteric reflux.

Radiological investigation is mandatory to establish a diagnosis, identify the type of the anomaly and rule out association with other anomalies.

Cystourethroscopy through the actual urethra will be useful if done to identify the opening of the accessory urethra in the bladder. Generally, accessory urethra is not scoped due to its narrow lumen.

Learning points.

• Even though a rare diagnosis, urethral duplication should be kept in mind when a patient with two streams of urine, or more commonly a recurrent urinary tract infection, comes to the physician.

• The diagnosis is to be confirmed radiologically with micturating cystourethrography (MCU).

• The treatment of each patient is to be tailored according to the level of duplication identified by the MCU, and it also dictates the type and the number of surgeries required to reconstruct the urethra.