Where have all the type I sphincter of Oddi patients gone?

Background: The Geenen-Hogan classification (GH) has been used to predict the likelihood of finding sphincter of Oddi dysfunction (SOD) and previous reports suggest a correlation with outcome after sphincterotomy (Type I > Type II > Type III). By definition, Type I patients (pts) have typical pain, elevated liver/pancreas lab tests during pain, dilated duct(s) and delayed drainage of contrast. The purpose of this retrospective study was to stratify our suspected SOD according to strict GH criteria and review their manometry results. Methods: We determined the GHC of all patients with postcholecystectomy pain (PCP) and those with unexplained pancreatitis who were referred for ERCP/SOM. Patients with prior biliary or pancreatic sphincterotomy (N=22) and patients with pancreatitis due to alcohol (N=19) were excluded. Results: SOM was successfully obtained in 109/110(99%) from one or both ducts. The GH for each group was: GHC Type I Type II Type III PCP 0/72 18/72 (25%) 54/72 (75%) Unexplained Pancreatitis 0/38 37/38 (97%) 1/38 (3%) Seven of 72 ( 9.7%) PCP pts had objective lab findings that did not fulfill the strict GH (>2x nl AST & ALP on 2 occasions) yet 5 of the 7 had abnormal SOM. Of 72 PCP pts, 25 had prior ERCP's, but only 3/25 (12%) had biliary drainage assessed, and in no case was this done property (pt in supine position immediately after contrast injection). Sixty-one percent of patients with Type II PCP, 74% of patients with Type III PCP, and 68% of patients with Type II pancreatic pain were found to have SOD. Summary: (1) Type I GH patients are rarely seen at referral centers. One explanation for this is that Type I patients are treated in the community without the use of SOM. (2) Drainage times are not being performed to evaluate for SOD and we suggest that modifications should be made to the GH to reflect this change in practice.