Table 1:

Summary of the 2020 Revised Comprehensive Diagnostic (RCD) Criteria for IgG4-Related Diseases.

Detailed Diagnostic (RCD) Criteria for IgG4-Related Diseases
1. Clinical and radiological feature	One or more organs show diffuse or localized swelling, mass, nodule characteristic for IgG4-related disease. In single organ involvement, lymph node swelling is omitted.
2. Serological diagnosis	Serum IgG4 levels are more than 135 mg/dL.
3. Pathological diagnosis	Positivity for two of the following three criteria:
	a. Dense lymphocyte and plasma cell infiltration with fibrosis.
	b. Ratio of IgG4-positive plasma cells/IgG-positive cells greater than 40% and the number of IgG4-positive plasma cells greater than 10 per high-powered field
	c. Typical tissue fibrosis, particularly storiform fibrosis, or obliterative phlebitis*
Diagnostic Classification	Definite: if +ve clinical and radiological features, +ve serological diagnosis, and +ve pathological diagnosis
	Probable: if +ve clinical and radiological features and +ve pathological diagnosis
	Possible: if +ve clinical and radiological features and +ve serological diagnosis