IGHA1 and lupus nephritis: Similarly, glomerular Gd-IgA1 deposition is not specific for IgAN and IgAV nephritis, but may also occur in IgAN with hepatitis B virus antigen or in lupus nephritis [only that their amount is higher in IgAN, and glomerular IgG seems indeed specific for Gd-IgA1 (35)].