K他命（Ketamine）長期濫用引起之膽道病變

Cholangiopathy Associated with Chronic Ketamine Abuse

K他命（ketamine）是一種解離性麻醉劑。它近年來卻被一些人濫用，成為一種產生幻覺及中樞興奮的毒品。K他命濫用最為大眾所熟知的後果是慢性膀胱炎及水腎，但最近學界卻更注意，K他命濫用所導致的膽道病變。我們在此報告了9例K他命濫用者合併膽道病變，它們是可逆性膽道擴張的變化。病人中有8例是20至30歲的年輕人，他們初始的表現包括意識失常、反覆上腹痛或慢性膀胱炎。腹部超音波、磁核共振膽胰管攝影術、腹部電腦斷層或內視鏡逆行性膽胰管造影術是我們用於診斷膽道病變的工具。其中有4例因起初誤判為膽管結石或括約肌功能不良（sphincter of Oddi dysfunction，SOD），而作了內視鏡括約肌切開術。膽道擴張的病人大部分合併肝功能異常（9例中有8例）。有一例病人作了肝臟生檢，結果只有輕微變化。過去文獻所報告的肝生檢亦呈現不同的結果，包括「硬化性膽管炎」的變化或橋連樣纖維化或非特異性發炎。將來更多的研究才能釐清這種歧異的結論。

Ketamine is a dissociative anesthetic agent. It is abused as a recreational hallucinogenic drug in recent years. It is well known that chronic ketamine abuse can induce chronic cystitis and hydronephrosis, but recent attention has been drawn to biliary tract disease in chronic abuser. We report 9 cases of ketamine abuse associated with reversible biliary dilatation. The ketamine abusers in our series are young (20-30 yrs old in 8 cases) and presented with impaired consciousness, recurrent upper abdominal pain or chronic cystitis. Abdominal sonography, CT scan (computerized tomography), MRCP (magnetic resonance cholangiopancreatography) and/ or ERCP (endoscopic retrograde cholangio-pancreatography) were used for the demonstration of biliary dilatation. Four cases received EST (endoscopic sphincterotomy) for misdiagnosis as common bile duct stone or SOD (sphincter of Oddi dysfunction). The biliary dilatation was associated with impaired liver function in 8 of 9 cases. Liver biopsy was performed in one of our cases and it revealed minimal change. Liver biopsy showed variable results in the published papers, including sclerosing cholangitis, bridge fibrosis or nonspecific inflammation. More studies are needed to clarify the differences in the future.