Congenital urethral fistula with normal anus: a report of two cases

Congenital rectourethral or anourethral fistulae without imperforate anus in males are rare, representing less than 1% of anorectal malformations. We report our experience with two males with "N type" urethral fistulae. One, a 5-year-old boy, presented with recurrent urinary tract infections (UTIs) and passage of urine per anus. Investigations included a voiding cystourethrogram (VCUG), which demonstrated a fistula from the urethra to the anus. On physical examination, a small perianal opening was noted just outside the anus, which drained a small amount of urine after voiding. The fistula was excised via a perineal approach. The second patient is a 5-year-old boy with a long history of recurrent UTI requiring multiple hospitalizations since the newborn period. Chronic renal failure developed as a complication of repeated urinary tract infections. Investigations showed a single hydronephrotic pelvic kidney and a small bladder. He underwent numerous diagnostic and reconstructive procedures including cystoscopy and augmentation cystoplasty. Recurrent infections continued and an N type anourethral fistula was eventually diagnosed. The fistula was located between the anal canal and the membranous urethra. An anterior perineal approach was also used. Both fistulae were easily located, and reconstructive surgery of the urethra was not required. Postoperative VCUGs in both patients were normal. They have been free of infection with normal urinary continence since resection of the fistula. Congenital N type anourethral fistulae are rare, but should be considered in cases of recurrent urinary tract infections. The diagnosis may be missed by endoscopic procedures, but VCUG should demonstrate the fistulous tract.