Major salivary gland enlargement in IgG4-related disease is associated with multiorgan involvement and higher basal disease activity

Objective: To evaluate if major salivary gland enlargement in patients with IgG4-related disease (IgG4-RD) is associated with systemic involvement. Methods: We included 47 patients with diagnosis of IgG4-RD. We retrospectively collected demographics, organ involvement, disease activity and damage assessed by the IgG4-RD Responder Index (IgG4-RD RI) and treatment. Results: 25 patients (53%) were men, mean age 50.8 years and median disease duration 27 months. Most frequently anatomic sites affected were lymph nodes 55%, pancreas 51% and lacrimal glands 43%. We observed major salivary gland involvement in 22 (46.8%) patients. When we compared patients with (n = 22) vs. without (n = 25) salivary gland enlargement, the first group had a higher number of affected organs, a higher prevalence of lacrimal glands, lymph nodes, and lung involvement, rheumatoid factor positivity, azathioprine and prednisone use, as well as a higher baseline IgG4-RD RI and a longer delay in diagnosis. At logistic regression analysis we found an association of major salivary gland enlargement with the basal IgG4-RD RI (OR 1.37, 95%CI 1.09-1.61, p = .001) and with lacrimal gland involvement (OR 34.7, 95%CI 4.6-258, p = .001). Conclusion: Our study highlights the systemic nature of IgG4-RD. Patients with major salivary gland enlargement should be routinely screened for multi-organ disease.