原田 淳樹, 木原 敏晴, 宮崎 佑也, 本多 弘幸, 中西 裕美, 宮田 康好, 酒井 英樹

Junki HARADA, Toshiharu KIHARA, Yuya MIYAZAKI, Hiroyuki HONDA, Hiromi NAKANISHI, Yasuyoshi MIYATA, Hideki SAKAI

長崎大学病院泌尿器科・腎移植外科

Department of Urology and Renal Transplantation, Nagasaki University Hospital

キーワード : urethral stone, hypospadias, urethroplasty, scrotal ultrasonography

症例は30歳男性．3歳で尿道下裂に対する尿道形成術を施行された．陰嚢内の硬結と終末尿滴下を主訴とし，精査で受けたmagnetic resonance imagingで長径3 cmの陰嚢内腫瘤を指摘されたため当科を紹介された．同腫瘤は陰嚢超音波検査で境界明瞭かつ音響陰影を伴い，computed tomographyや尿道造影検査の結果も合わせて，形成尿道内の尿道結石と診断された．外尿道口狭窄のため経尿道的砕石術が困難であり，外尿道口と形成尿道の一部を切開し尿道結石を摘出した．尿道結石は尿道下裂形成術後の晩期合併症の1つであり，尿道狭窄や尿道憩室，形成尿道内の発毛がその原因とされる．陰嚢超音波検査が診断の契機となり，成人期に巨大な形成尿道内結石を摘出した1例を経験したので報告する．

A 30-year-old man, who underwent urethroplasty for hypospadias at three years of age, visited a hospital complaining of scrotal induration and terminal dribbling. Magnetic resonance imaging for assessing this induration revealed a 3-cm subscrotal mass. Thereafter, the patient was referred to our department for further evaluation. Scrotal ultrasonography demonstrated a well-circumscribed mass with acoustic shadowing. Based on image findings of ultrasonography, computed tomography, and urethrography, he was diagnosed with urethral stone in the neourethra. Since it was impossible to perform transurethral lithotripsy owing to severe meatal stenosis, this urethral stone was removed by meatotomy and incising a part of the patient's neourethra. Urethral stone is recognized as one of the late complications after urethroplasty for hypospadias. Urethral stricture, diverticulum, and hair are causes of urethral stone following hypospadias repair. In this case, scrotal ultrasonography was an important and useful modality for us to strongly suspect that the subscrotal mass was a huge urethral stone.