Primary urethral stones are a rare cause of acute urinary retention.[1,2] In this patient, long standing benign prostate enlargement predisposed him to the development of the bladder diverticulum. Any cause of bladder outlet obstruction such as neurogenic bladder, posterior urethral valves, benign prostate enlargement, or urethra stricture may be complicated by bladder or urethral stones as seen in this patient. Our patient presented with acute urinary retention as well as difficulty with urethral catheterization. Prolonged urethral catheter leads to formation of encrustations around the catheter balloon resulting in catheter retention. Similarly, the prolonged lower urinary tract symptoms in this patient may account for the bladder diverticulum and diverticular stones prior to the TURP. The sudden bladder decompression following the catheter removal could be responsible for the stones being driven down the urethra.
During the TURP the diverticulum mouth was widened but the stones could not be extracted probably due to their sizes. Supra pubic cystolithotripsy then followed by TURP or simultaneous suprapubic cystolithotripsy and TURP is preferred. In the developing country with limited endoscopic equipment, open retropubic or transvesical prostatectomy, diverticulectomy and stone removal is an alternative treatment. This may reduce the patient's agony.
Imaging studies often localize these stones commonly in the posterior urethra[6–9] or anterior urethra though at times computed tomography may not be able to identify impacted urethral stone. In our patient the plain radiograph of the pelvis and male external genitalia confirmed the anterior and posterior urethral stones (steinstrasse).
Other reports and studies have demonstrated that urethral stones could be easily pushed back either manually with a catheter or endoscopically into the urinary bladder[2,6,8] This was not our experience, as the impacted urethral stones was not pushed back, hence meatotomy, antegrade manual extraction, generous urethral lubrication with 2% xylocaine jelly was performed. Urethral stones that are pushed into the urinary bladder are removed by open cystolithotomy in the tropics where facilities are not available. While in the industrialized countries, extra corporeal shock wave lithotripsy or cystolithotripsy are effective and safe options of treatment. Electrohydraulic endourethral lithotripsy is quite good for accessible urethral stones and is least traumatic.
Urethro-cystoscopy confirmed complete stone removal with no urethral injury.
BMC Urol. 2012;12(31) © 2012 BioMed Central, Ltd.