Bladder stone secondary to migration of an acupuncture needle

A 61-year-old man who had been suffering from benign prostatic hyperplasia (BPH) for ten years visited our hospital complaining of dysuria and bladder pain. Abdominal X-ray showed a 2 cm calculus containing a needle-like shadow in the pelvis. Transurethral lithotripsy and trunsurethral resection of the prostate (TURP) were done. The calculus was a brown club-shaped bladder stone with the core being a 2 cm needle one side of which was broken. It was supposed to be an acupuncture needle that was retained in his back twenty years ago. This is the first case of a bladder stone secondary to migration of an acupuncture needle.