Endoscopic therapy of recurrent acute pancreatitis
ABSTRACTEndoscopic therapy has emerged as an alternative to surgery for the subset of patients with acute recurrent pancreatitis whose disease is due to gallstones or other mechanical processes that obstruct the outflow of the pancreas. In this article, the authors review the specific situations in which endoscopic therapy might be useful in patients with acute recurrent pancreatitis.
KEY POINTS
- Recurrent attacks of acute pancreatitis can be prevented only by determining and treating the underlying cause.
- Endoscopic procedures can cause anxiety and carry a risk of bleeding, perforation, and pancreatitis. The risks, benefits, and other treatment options should be discussed with the patient.
- Endoscopic therapy is now the preferred treatment of sphincter of Oddi dysfunction at centers that have experience with this technique.
- In patients with pancreas divisum and recurrent acute pancreatitis, surgical and endoscopic minor sphincterotomy are equally effective.
OTHER PROCESSES OBSTRUCTING THE FLOW OF PANCREATIC JUICE
Any process preventing free flow of pancreatic juice can lead to acute pancreatitis. The cause of the blockage can be around the ampulla, in the ampulla, or in the duct.61
Periampullary lesions, tumors, or polyps can press on the ampulla and cause complete or relative obstruction of the pancreatic duct with a subsequent increase in intraductal pressure and, thus, acute pancreatitis.62 Tumors or polyps of the ampulla, such as ampullary adenoma or carcinoma, can cause pancreatitis by directly obstructing the pancreatic duct where it opens into the duodenum.63–66 Intraductal processes such as ductal adenocarcinoma, intraductal papillary mucinous tumor, pancreatic duct stone, and intraductal stricture due to cancer, chronic pancreatitis, or trauma can also cause pancreatitis by preventing free flow of pancreatic juice.67–71
Although it is well known that sequelae of severe chronic pancreatitis such as ductal strictures or intraductal stones can lead to recurrent attacks of acute pancreatitis by preventing the free flow of pancreatic juice, a relationship also seems to exist between early chronic pancreatitis and recurrent acute pancreatitis.72 Several studies have shown that up to 50% of patients with idiopathic recurrent pancreatitis have evidence of chronic pancreatitis.72–74 However, it is still unclear whether early chronic pancreatitis is the underlying cause of the recurrent attacks of acute pancreatitis or whether recurrent attacks of acute pancreatitis might have led to the development of chronic pancreatitis.
Diagnosis
Ampullary and periampullary neoplasms can be diagnosed endoscopically. Intraductal lesions such as strictures can be diagnosed by MRCP, especially secretin-enhanced MRCP, or by ERCP. ERCP has the additional advantage of being able to deliver treatment, ie, balloon dilation and stenting. In the case of ductal strictures, upsizing of the stents or placement of multiple stents during subsequent procedures is usually needed. Pancreatic ductal calcifications associated with chronic pancreatitis are usually radiopaque and are easily visible on plain films or computed tomography of the abdomen. Parenchymal and ductal changes of chronic pancreatitis can be diagnosed by endoscopic ultrasonography.
Treatment
The treatment is to relieve the obstruction and re-establish the free flow of pancreatic juice.
Periampullary tumors or polyps can be resected surgically or, if they involve only the mucosa, by endoscopic mucosal resection. Ampullary adenomas can be resected endoscopically. Ampullary carcinomas usually require surgical resection.
Small, nonobstructive stones in the pancreatic duct can be removed during ERCP.75 Larger stones may need to be fragmented by extracorporeal shock wave lithotripsy to facilitate removal by ERCP.75
Intraductal strictures should raise the suspicion of pancreatic adenocarcinoma, especially in older patients.61 In these cases, relief of the obstruction by placement of a pancreatic stent can prevent further attacks of pancreatitis until a diagnosis can be established and a more definitive treatment can be offered.
