Cowper's Syringocele: A Rare Cause of New-Onset Voiding Dysfunction

Abstract

Cowper's syringocele is a condition caused by dilatation of the main duct of Cowper's gland. It is a very uncommon cause of urethral obstruction. Closed type causes urinary obstruction. The aim of this article is to report a case of closed type syringocele causing new-onset urinary obstruction in a 10-year-old boy.

INTRODUCTION

Bulbourethral glands, also known as Cowper's glands, are accessory sexual organs that contribute to the function of lubrication of urethra. Syringocele is a condition where there is a dilatation of the main duct of Cowper's gland, an uncommon cause of urethral obstruction.[1] Two types of syringoceles have been described, open and closed. Open type causes postvoid dribbling of urine, whereas closed type causes urinary obstruction.[2] The aim of this article is to report a case of closed-type syringocele causing new-onset urinary obstruction in a 10-year-old boy.

CASE REPORT

A 10-year-old boy presented with complaints of straining at micturition and urinary dribbling for 2 months only. Physical examination was unremarkable. Urine examination and renal function tests were normal. Ultrasound of the abdomen was normal, except for significant postvoid residual urine. Micturating cystourethrogram (MCUG) showed a normal urethra, normal bladder, and no evidence of vesicoureteral reflux, but the boy could not void in a stream and only had urinary dribbling despite straining.

Cystoscopy revealed a mildly trabeculated bladder with normal bladder neck and posterior urethra. A cystic translucent swelling [Figure 1] was noted in the posterior wall of the bulbar urethra, with a punctum/pinhole opening on its dome. A diagnosis of Cowper's syringocele was made. The syringocele was deroofed using a Bugbee electrode, which decompressed the cyst completely [Figure 2]. Bladder catheter was kept in situ for 5 days, and after its removal, the child passed urine in a good stream. He had neither straining nor urinary dribbling and is completely asymptomatic at 12 weeks of follow-up.

Figure 1.

Cowper's syringocele seen as cyst-like bulging in the bulbar urethra

Figure 2.

Post deroofing of syringocele using Bugbee

DISCUSSION

Cowper's syringocele is a rare cause of bladder-outlet obstruction in children, with literature limited to case reports and three pediatric case series. Cowper's syringocele arises due to the dilatation of the main duct of Cowper's gland. The Cowper's or bulbourethral glands are paired glands lying on either side of the membranous urethra in the dorsal aspect.[1] While the main Cowper's glands are present on the urogenital diaphragm, the accessory glands lie deeply within the bulbar urethral spongiosal tissue. Majority of the ducts combine to make a single confluent passage that opens in the posterior aspect of the bulbar urethra.[1]

Bever et al. classified syringoceles into open and closed types based on the configuration of the duct orifice to the urethra.[2] Open syringocele causes postvoid urinary dribbling, whereas the closed type causes obstructive symptoms.[3] Some closed types even cause perineal pain. Some syringoceles can cause severe urinary obstruction, leading to vesicoureteral reflux and renal failure.[3]

Theories regarding the genesis of syringocele include a mouse model where a deletion of transformation growth factor beta-2 gene exhibits hyperplasia of the Cowper's gland epithelium and cystic dilatation of the gland ducts.[4] Acquired theory proposes that the gland's duct can get obstructed due to inflammation or instrumentation, leading to retention of the mucous and causing dilatation of the duct.[4] Of note, Cowper's syringocele has also been reported as a cause for intrauterine or early postnatal death.[5]

In the present case, the boy had recent-onset urinary obstruction and cystoscopy was suggestive of a closed type of syringocele. The punctum/pinhole appearance was probably the obliterated orifice of the duct. Cystourethroscopy remains the gold standard for diagnosing Cowper's syringocele,[3] although MCUG and uroflowmetry may raise suspicion. Cystoscopic deroofing using diathermy hook (Bugbee) is the treatment of choice.

The present case report provides the presentation and treatment of closed type of Cowper's syringocele, which is an uncommon cause of urethral obstruction, thus guiding the pediatric surgeons to consider in the list of differential diagnosis for new-onset lower urinary tract symptoms in children. Cystourethroscopy is the gold standard for diagnosis as well as therapeutic management by incision of the syringocele.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the guardian has given his/her/their consent for his/her/their child's images and other clinical information to be reported in the journal. They understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.