Outcome of valve ablation in late-presenting posterior urethral valves

Abstract

Objective: To explore the symptoms, radiological findings and outcome after valve ablation in patients who present late with posterior urethral valves (PUV) and who typically have mild forms of the disease with often minimal upper tract changes; these patients frequently escape detection by ultrasonography in utero and the diagnosis may be delayed to as late as adolescence.

Patients and methods: The charts of 70 boys (mean age 7.46 years, range 2-14) diagnosed late with PUV and treated with value ablation were retrospectively reviewed. Before ablation, history of voiding habits, voiding frequency, presence of enuresis, dysuria and the incidence of gross haematuria was recorded. Findings of a physical examination, laboratory testing (urine analysis and serum creatinine levels), ultrasonography and voiding cysto-urethrography (VCUG) were noted. After valve ablation, a review included a detailed voiding history and re-examination of abnormal variables including an assessment of enuresis, voiding frequency and ultrasonography. The mean (range) follow-up was 25 (1-78) months. One patient was lost after his first follow-up visit, but data were included to that time.

Results: The most common presenting symptom was voiding dysfunction; 47 (67%) presented with nocturnal enuresis, 42 (60%) with urinary frequency and 12 (17%) with a history of urinary tract infection. On physical examination 12 (17%) had mild age-corrected hypertension. Microhaematuria was present in 21 (30%) but all patients had normal serum creatinine levels. Ultrasonography showed hydronephrosis in 33 (47%) and a postvoid residual volume in 57 (81%). On VCUG, 52 (79%) patients had clear evidence of PUV, 22 (31%) bladder trabeculation, 11 (16%) vesico-ureteric reflux and eight (11%) diverticula. On cystoscopy, 67 (96%) patients presented with the classic sail-shaped PUV and three a ring-shaped valve. After surgical ablation of the valve most patients dramatically improved; 31 of 42 (74%) had resolution of urinary frequency, 24 of 33 (73%) of diurnal enuresis and 17 of 47 (38%) nocturnal enuresis. Of 57 patients, 39 (68%) established good bladder emptying. Of 33 affected, 20 (60%) had some reduction of hydronephrosis but 63% continued to have some symptoms of voiding dysfunction.

Conclusion: PUV should be considered in boys presenting with voiding dysfunction. After valve ablation most patients improve dramatically. Despite surgery, enuresis, urinary frequency and poor bladder emptying persisted in some and required further treatment. The continued bladder dysfunction suggested that irreversible urinary tract damage may have occurred. Even in this apparently mildly affected group, long-term follow-up is essential.