Y-Type Urethral Duplication: A True Variant of the Anomaly or a Misnomer?

Abstract

Objectives The objective of this study was to define anatomical and radiological features of the so-called Y-type urethral duplication. Methods The study included four male patients and one female patient with congenital connection between the urogenital tract and the external anal orifice. Investigations included renal sonography, urethrograms, and magnetic resonance imaging pelvis in the last patient. The urethrograms of male patients were carefully reviewed, in addition to available urethrograms of similar cases that could be obtained through searching the literature. Results Unlike cases of urethral duplication, the male patients had always a complete prepuce and a functioning anterior urethra in 25%. The accessory uroanal channel had almost always a constant origin from the posterior urethra. Some tension seems to be exerted by the urethroanal tract pulling on and causing a kink in the posterior urethra. Management was simple in patients without anterior urethral hypoplasia (one male and the female patient). Both were treated by simple excision of the communicating ano-urogenital tract through a perineal approach with an excellent outcome. Histopathological examination of excised tracts revealed stratified squamous cell in the former and transitional cell lining in the latter. In patients with hypoplastic anterior urethra, staged urethral reconstruction was performed in two, and progressive dilatation of hypoplastic anterior urethra was tried in the last patient. Conclusion Several observations would support diagnosing the congenital connection between the urinary tract and the external anal orifice in the male as a congenital fistula rather than an accessory urethra. Confirming and accepting this information may have its impact on changing the current surgical approach.

The so-called Y-type urethral duplication: anatomical insights through controversial terminology

“…Other reports described this condition as congenital "H-type" urethro-anal fistula analogous to the H-type trachea-esophageal fistula at the other (proximal) end of the gastrointestinal tract [5,6]. In a previous report, we have brought several observations that support the diagnosis of this abnormal uro-anal communication as a "fistula" rather than a "true" urethral duplication [7].…”

“…During the period between 2016 and 2021, the study included two newly diagnosed cases with abnormal communication between the lower urinary tract and the anus (the so-called Y-type urethral duplication), in addition to one previously reported case [7] whose preoperative imaging studies (including pelvic MRI) were available for analysis. Different surgical solutions have been applied for each case.…”

“…This report discusses one of the rare congenital anomalies where there is abnormal communication between the lower urinary tract and the anus. This condition may be inadvertently classified as a type of urethral duplication [7]. We believe that proper identification of the true nature of the disease can help to improve and standardize surgical management.…”

“…The process of complete separation of the anorectum from the lower urinary tract may become interrupted by the presence of obstruction (atresia) either at the anal side or the urethra; this would result in persistence of abnormal communication between both tracts (persistent cloacal duct of Reichel) [5,6,13]. In the literature, it is well documented among boys with imperforate anus that the rectum usually remains communicating via a fistula with the urinary tract (recto-bulbar/prostatic/bladder neck) [7]. On the other hand, urethral atresia is a much less common disorder; the condition is usually lethal causing fetal death due to severe renal dysplasia and lung hypoplasia unless urine can find its way out (escape) through a patent urachus or persistent communication with the anus [14].…”

“…Stephens and Donnellan showed this urethro-anal tract to be devoid of muscle coat; moreover, it showed severe shrinkage during specimen preparation. This may explain the reported high incidence of strictures and failure when using the accessory uro-anal tract in reconstruction of the urethra and would indicate for its true fistulous nature [7]. Sinha et al reported using a strip of rectal wall in continuity with the posterior ectopic urinary meatus adding extra length to the uro-anal tract during its mobilization to the anterior perineum [15].…”