Addition of second-line steroid sparing immunosuppressants like mycophenolate mofetil improves outcome of Immunoglobulin G4-related disease (IgG4-RD): a series from a tertiary care teaching hospital in South India.

IgG4-related disease (IgG4-RD) is a systemic fibro-inflammatory disease. This disease may be associated with elevated serum and tissue IgG4 levels. Early treatment prevents fibrosis and organ damage. We retrospectively studied the clinicopathologic correlation and outcome of treatment in IgG4-RD. This single-center retrospective study was done using electronic records of patients subjected to assay of serum IgG4 levels in our laboratory by nephelometry. There were 473 patients with suspected IgG4-RD. Of them, 41 patients fulfilled comprehensive diagnostic criteria for IgG4-RD and 432 had diseases other than IgG4-RD. Clinical and histopathological data including tissue IgG4/IgG ratio, other relevant laboratory findings as well as management data of 41 patients with IgG4-RD were analyzed. There were 29 males and 12 females with mean age of 44.1 ± 2.19 years. Thirteen patients had definite, 19 had probable and 9 had possible IgG4-RD. Male predominance, multiple organ involvement and IgG4 responder Index were significantly higher in definite IgG4-RD as compared to probable and possible IgG4-RD. Serum IgG4 level was elevated in 37 patients (90.2%). Glucocorticoids were used in 35 patients (85.4%) and second-line immunosuppressive agent in 23 patients (65.7%). Of the 21 patients on follow-up, 19 (90.7%) had clinical improvement at the first follow-up visit. Nine (90%) out of the ten patients who were assessed by IgG4 responder index, also had shown improved score with treatment. Patients with IgG4-RD in our series showed favorable responses to treatment with glucocorticoids and addition of steroid sparing immunosuppressive agents (mainly mycophenolate mofetil) helped successful tapering of steroids, while maintaining the improvement.