Anterior urethral valves: Not such a benign condition.

Abstract

Purpose: Anterior urethral valves (AUVs) is an unusual cause of congenital obstruction of the male urethra, being 15-30 times less common than posterior urethral valves (PUVs). It has been suggested that patients with congenital anterior urethral obstruction have a better prognosis than those with PUV, with less hydronephrosis, and a lower incidence of chronic renal insufficiency (5 vs. 30%). The long-term prognosis of AUVs is not clear in the literature. In this report we describe our experience and long-term follow up of patients with anterior urethral valve. Materials and Methods: We retrospectively identified 13 patients who presented with the diagnosis of AUVs in our institutions between January 1994 and June 2012. Two patients were excluded: one patient had no follow up after intervention; the other had a follow up <1 year. From the 11 patients included, we evaluated the gestational age, prenatal and postnatal ultrasound findings, voiding cystourethrogram findings, age upon valve ablation, micturition pattern, creatinine, and clinical follow up. Results: Between 1994 and 2012 we evaluated 150 patients with the diagnosis of urethral valves. Of this group, 11 patients (7.3%) had AUVs and an adequate follow up. Mean follow up is 6.3 years (2.5-12 years). Five (45.4%) patients had prenatal diagnosis of AUV. The most common prenatal ultrasonographic finding was bilateral hydronephrosis and distended bladder. One patient showed a large perineal cystic mass, which was confirmed to be a dilated anterior urethra. The mean gestational age was 37.6 weeks (27-40 WGA). Postnatally, 90% had trabeculated bladder, 80% hydronephrosis, and 40% renal dysplasia. The most common clinical presentation was urinary tract infection in five patients (45.4%), followed by weak urinary stream found in four patients (36.3%). The age at initial surgical intervention ranged between 7 days and 13 years. Seven (63.6%) patients had primary transurethral valve resection or laser ablation and three patients (27.2%) had primary vesicostomies. One boy (9.1%) had penile urethrostomy with excision of urethral diverticulum. Two (18.2%) patients developed end-stage renal disease. Conclusion: Anterior urethral valve is a rare congenital entity affecting the genitourinary system in males. Early urinary tract obstruction resulted in end-stage renal disease in 18% of our patient population. In our series, the complication rate and the evolution to renal failure are high and similar to patients with PUV. In patients with AUVs we recommend long-term follow up and close evaluation of patient's bladder and renal function.