Urethral duplication, also known as accessory urethra, is a rare anomaly occurring almost exclusively in boys. It has been reported in girls in association with bladder duplication. It almost always occurs in the sagittal plane. The term includes a wide variety of presentations, i.e., complete duplications, y-shaped variants with bifid configuration, spindle shaped urethra with a proximal and distal connection and a single meatus, etc.. There may be a single meatal opening or separate openings. The openings can be described as epispadic or hypospadic depending on the site of opening with respect to the glands penis. A single underlying embryologic cause has not been elucidated. Importantly, in nearly all cases, the ventrally positioned urethra is the functional one.
Patients may present with two urinary streams one of which may emanate from the vagina or anus. UTI can also be a presenting symptoms, especially if there is associated stenosis of the accessory urethra. Treatment varies with the type of duplication, but identification of the urethral extent and functional urethra with VCUG is required. Again, the ventrally positioned urethra is nearly always the functional one, but care must be taken to not confuse a ventral duplication to the perineum with a congenital urethral perineal fistula (Example).
Urethral Duplication (Triplication)
A. Urethral triplication
B. Posterior urethra
B
A
A
A
A. Suprapubic catheter
B. Short posterior urethra
C. Ventral functional urethra
D. Dorsal urethra
D
A
B
C
