In sphincter of Oddi patients, amelioration of pain is primarily associated with common bile duct dilation rather than hepatobiliary scintigraphy excretion time or alanine amino transferase – a single centre, retrospective study

There are few reliable predictors for reduced pain after biliary sphincterotomy or medical therapy in patients with sphincter of Oddi dysfunction (SOD). We explored whether prolonged intestinal bile excretion time, dilated common bile duct (CBD) diameter, or elevated alanine aminotransferase (ALT) were associated with reduced pain after treatment for SOD. This is a retrospective, single-centre study. Consecutive patients suspected of SOD were identified and screened. Medical treatment for SOD followed institutional standards in line with the Regional pain medication guidelines. The primary outcome was potential prognostic markers for reduced pain. In the biliary sphincterotomy group (n = 34), 85% patients experienced reduced pain when evaluated in the outpatient clinic, while 60% of patients receiving medical therapy (n = 159) experienced reduced pain (p = 0.009). No association was found between the hepatobiliary scintigraphy excretion time nor ALT and reduced pain in either treatment group. However, a dilated CBD was associated with reduced pain (odds ratio 2.89; 95% CI [1.02;8.17]). In SOD patients, amelioration of pain in both medically and surgically treated patients is primarily associated with common bile duct dilation, rather than hepatobiliary scintigraphy excretion time or ALT.