Does sphincter of Oddi dysfunction cause chronic pancreatitis?

Sphincter of Oddi dysfunction (SOD) occurs in some patients with chronic pancreatitis (CP). If SOD is causative, a spectrum of severity of CP should be seen with some patients having early changes detectable only by sensitive diagnostic techniques. Methods: Patients with pancreatico-biliary type pain with no objective evidence of either acute or chronic pancreatitis were studied with sphincter of Oddi manometry (SOM) and evaluated for evidence of CP. Patients with pancreas divisum (n=21) or inadequate pancreatography (n=7) were excluded. SOM was performed using a triple lumen water perfused catheter (one port used for aspiration), and considered abnormal if both perfused leads were ≥ 40 mmHg. Pancreatic ductography (Cambridge classification), endoscopic ultrasound (EUS), and secretin stimulated pure pancreatic juice (PPJ) (abnormal HCO3 < 95 mmol/L) were used to detect CP. Chronic pancreatitis was graded as severe (Cambridge severe or Cambridge moderate plus either ≥ 5 of 7 EUS criteria or abnormal PPJ), or mild to moderate (either Cambridge moderate, ≥ 3 EUS criteria, or abnormal PPJ; or Cambridge mild plus ≥ 3 EUS criteria or abnormal PPJ). Results: Eighty-three patients (72F, 11M) with post-cholecystectomy pain (n=69) or pain with gallbladder in situ (n=14) were evaluated with SOM and pancreatography; 37 underwent EUS and 40 had PPJ HCO3 analysis. The patients are classified according to SOM results and evaluation for CP below. Chronic Pancreatitis SOD None Mild - Moderate Severe YES 31 18 0 NO 29 4 1 There was no evidence of CP in 63% (31/49) of SOD patients. Early (mild to moderate) CP was found in the remaining 37% (18/49) of SOD patients, and 44% (8/18) had isolated pancreatic SOD. Patients with SOD and evidence of early CP were significantly older than those without CP (54 ± 4 vs 42 ± 2 yr, respectively p=0.01). Conclusions: These data support a causative relationship between SOD and chronic pancreatitis.