Background: Endoscopic palliation in malignant hilar biliary obstruction requires ERCP. However, contrast injection leads to cholangitis. Recently, contrast-free metal stenting with or without MRCP has shown encouraging results. However, MRCP and metal stents are costly. There have been no reports on the use of air cholangiography in these patients. Methods: We prospectively studied the role of air cholangiogaphy assisted unilateral plastic stenting in these patients. Results: Ten patients with unresectable malignant hilar biliary obstruction were studied. Air cholangiography detected type II obstruction in 8 and type I in 2 patients which is similar to MRCP. All patients underwent unilateral plastic stenting. A successful endoscopic drainange was achieved in 100% patients. Cholanngitis occurred in none and there was no 30-day mortality. No major complications were observed. Conclusion: Air cohlangiography assisted plastic stenting in these patients is a safe and effective method of palliation. However, it requires a larger study. Introduction: A description of IgG4-related sclerosing cholangitis (IgG4-SC) without pancreatic lesion has recently been reported. In addition to imaging, diagnosis relies on findings of elevated serum IgG4 and immunodetection of invading IgG4-positive cells. Here we report a case of IgG4-SC with only slight common bile duct abnormalities and normal pancreatic findings. Case Study: A 65-year-old man suffering from cephalalgia, general malaise and muscle ache was admitted to our hospital. His blood examinations on admission revealed eosinophilia, mild anemia, liver dysfunction and an IgG level of 2820 mg/dl (IgG4 374 mg/dl). Although ERCP did not reveal typical stenosis or irregularities of the bile duct wall, visualization of peripheral bile ducts was slightly impaired. Echography revealed thickening of the intrahepatic bile duct and gallbladder walls as well as adenopathy. Due to a gradual increase in pleural effusion and a progression of anemia, oxygenation was begun on the seventh day of illness. Based on the combination of eosinophilia, elevated serum IgG4 levels, image findings and a negative result for helminth, IgG4-SC was suspected. Liver biopsy was performed on the ninth day of illness and steroid therapy was initiated, after which symptoms and laboratory findings improved. The IgG4-positive plasmocytic infiltrate present around the portal region at the time of biopsy disappeared within eight months of treatment. Summary: This case displayed two unusual features that are not generally observed with IgG4-SC: complications due to hemolytic anemia, and destruction of the peripheral bile duct with little damage to the common bile duct. Introduction: Various systemic diseases have been reported to be associated with IgG4. Although steroids are effective in the treatment of IgG4-related diseases, there are some reports on relapses with their treatment, and cases are often difficult to differentiate from malignant diseases. We encountered a case of autoimmune pancreatitis with sclerosing cholangitis (AIP-SC), in whom CA19-9 was elevated with episodes of exacerbation and an elevated serum IgG4 concentration. IgG4 staining was also useful for the diagnosis. Case Study: An 81-year-old woman noticed tumors beneath the bilateral jaw and was found to have an elevated level of CA19-9 (304) seven years previously. Her left submandibular gland was removed and diagnosed as sclerosing sialadenitis. Four years previously, she was diagnosed as having diabetes mellitus complicated by a recurrence of CA19-9 (419) elevation and liver dysfunction. Cholangiocarcinoma was suspected based on ERCP, but was not confirmed by histologic findings of bile duct biopsy. Elevated IgG4 and other test results established the diagnosis of AIP-SC, so steroid therapy was initiated, after which symptoms and laboratory findings improved. This recurrence of CA19-9 elevation (634) was diagnosed as a relapse of AIP-SC based on an increased IgG4 level and histologic findings. Summary: Some papers have reported that IgG4-positive cells are found in liver tissue in this disease, but such cells were not detected in the liver specimens in our case. This might be because intra-liver sites may have differed in the degree of morbidity, and long-term steroid therapy might have suppressed inflammation in the liver tissue.