EFFECTIVE STEROID MINI-PULSE THERAPY FOR REFRACTORY BILIARY STENOSIS DUE TO AUTOIMMUNE PANCREATITIS

Abstract

Autoimmune pancreatitis (AIP) is a recently described unique form of chronic pancreatitis, characterized by sausage-like diffuse swelling of the pancreas, diffusely irregular narrowing of the main pancreatic duct, and a high serum IgG4 concentration.1-3 Although most patients with AIP respond to oral steroid therapy, we report a case of refractory biliary stenosis due to AIP that was dramatically improved with steroid mini-pulse therapy for a short period. A 62-year-old man visited another hospital, complicating of general fatigue and jaundice. Because sausage-like diffuse swelling of the pancreas, diffusely irregular narrowing of the main pancreatic duct, and smooth stenosis of the lower bile duct on imaging studies, and a high serum IgG4 concentration, the diagnosis of AIP accompanied by biliary stenosis was made. After endoscopic biliary stenting, oral prednisolone was started. Although the symptom, diffuse pancreas swelling, and pancreatic duct narrowing improved, the biliary stenosis had no effects (Fig. 1, top). The patient was admitted to our hospital for further investigations. Because the patient refused re-treatment with high-dose oral prednisolone, we treated him with weekly 2 courses of steroid mini-pulse therapy (500 mg/day methyl-prednisolone for 3 days). 2 weeks later, the biliary stenosis improved dramatically (Fig. 1, bottom), and a biliary stent was not required. Oral prednisolone was prescribed as a maintenance treatment, and was gradually reduced. The patient has remained asymptomatic without elevations of hepatobiliary enzymes or biliary stenosis. Steroid pulse therapy is a well-recognized alternative for refractory autoimmune disorders.4 Because the patient refused re-treatment with high-dose oral prednisolone, we applied steroid mini-pulse therapy in the patient, resulting in dramatically resolution of the biliary stenosis for a short period. We recently reported another case of the bilio-enteric anastomotic stenosis caused by AIP, that was also dramatically improved with steroid mini-pulse therapy for a short period.5 When oral steroid therapy for AIP is ineffective, steroid mini-pulse therapy should be considered.FIGURE 1: After oral steroid therapy, irregular pancreatic duct narrowing improved, but the smooth stenosis of the lower bile duct remained (top). After steroid mini-pulse therapy, the biliary stenosis improved dramatically (bottom).