Immunosuppressant treatment for IgG4-related sclerosing cholangitis: A case report.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a multi-system fibroin-flammatory disorder that can involve any organ, including the salivary glands, pancreas, and biliary tree. Treatment of immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) is similar to that for IgG4-RD, but progression is irreversible in some cases. We present a case of IgG4-SC in which an immuno-suppressant induced marked clinical and radiologic improvement.

CASE SUMMARY: A 63-year-old male presented with a prominent itching sensation and wholebody jaundice. He showed obstructive-pattern jaundice, an elevated IgG4 level, and infiltration of a large number of IgG4-positive cells in the ampulla of Vater. The imaging findings of i ntrahepatic duct (IHD) and common bile duct dilation, an elevated serum IgG4 level, and characteristic histological findings led to diagnosis of IgG4-SC that compatible with the 2019 ACR/EULAR classification criteria. We planned to treat the patient with high-dose glucocorticoid (GC), followed by cyclophosphamide pulse therapy. After treatment with high-dose GC and an immunosuppressant, imaging studies showed that IHD dilatation had completely resolved.

CONCLUSION: Prompt diagnosis and appropriate treatment of IgG4-SC are important. Because there is a risk of relapse of IgG4-SC, the GC dose should be gradually reduced, and a maintenance immunosuppressant should be given.