A urinary calculi stuck in the penile urethra! The clips in action make the diagnosis painfully clear.
Urethral stones are a rare occurrence, and account for less than 2% of all urinary tract calculi. They are classified as primary stones, which form in situ due to underlying urethra pathologies such as strictures and diverticula, or more commonly secondary stones, which originate upstream in the urinary tract and migrate down to the urethra. When large enough, they can cause impaction, typically in the prostatic urethra.
Patients with an impacted urethral calculus usually present with acute retention of urine, severe pain as well a lower urinary tract symptoms such as urgency and frequency. Diagnosis is usually through radiographic imagining and 98% of stones are usually diagnosed using simple radiographs. Urethral imaging has also been traditionally performed with retrograde urethrography, but more recently, ultrasound has been used as an alternative, pain free method for obtaining detailed information about urethral pathology, though it is not usually part of the standard evaluation of patients who present with such symptoms.
The male urethra consists of both the posterior (prostatic and membranous) urethra and anterior (the bulbous and penile) urethra. Stones can occur throughout the length of the urethra and while the posterior urethra is better visualized via the use of a transrectal ultrasound, the anterior urethra can be imaged easily by placing the transducer probe directly over the shaft of the penis.
Impacted urethral stones are usually treated by pushing the stone back into the bladder for subsequent lithotripsy, in situ lithotripsy or open surgery. Attempts to manually manipulate the calculus back into the bladder should be best done by a trained urologist. In this case, the pelvic XRay demonstrated the presence of 0.4 cm opacity projected just inferior to the pubic symphysis. The patient underwent flexible cystoscopy and reduction of urethra calculi by the duty urologist and was admitted post procedure for monitoring. He was discharged well.
Hanna Bielawaska, MD; Norman L. Epstein, MD. “A stone down below: a urethral stone causing acute urinary retention and renal failure.’ CJEM 2010;12 (4):377-380
Christopher Peabody MD, Thomas Mailhot, MD and Phillips Perera, MD. “Ultrasound diagnosis of urethral calculi” West J Emerg Med. 2012 Dec; 13(6): 515
Dr. Yeo Eng Hui, Damien
NHG Emergency Medicine Residency Program
Emergency Department, Tan Tock Seng Hospital
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