It Melts Like Snow: Steroid Responsiveness of Immunoglobulin G4-Related Disease

Abstract

Dear Editor, A 35-year-old male presented with insidious onset gradually progressive bilateral painless submandibular swelling, followed by periorbital swelling [Figure 1] for the past 7 years. He had no constitutional or sicca symptoms. He had no history of addiction or autoimmunity in the family. Systemic examination was unremarkable. On evaluation, he had raised inflammatory markers with a negative autoimmune panel. Magnetic resonance imaging orbit showed bilateral orbital extraconal soft-tissue masses with contrast enhancement. Incisional biopsy from the extraconal mass was suggestive of fibrocollagenous stroma with aggregation of lymphocytes, plasma cells, and histiocytes without any necrosis or granuloma. On further evaluation, submandibular gland biopsy showed chronic sialadenitis with immunoglobulin G4 (IgG4)-positive plasma cell >10/hpf and IgG4: IgG ratio >40% [Figure 2] without any major organ involvement on imaging. The diagnosis of IgG4-related disease was kept. He was started on oral steroid 0.5 mg/kg/day and observed a rapid clinical response within 15 days of steroid therapy. Later, he was started on azathioprine and continued with tapering dose of steroid. He was followed up every month for first 3 months and then every 3 monthly upto 16 months without any signs of recurrence. For a long-standing indolent disease of 7 years, drastic steroid response with resolution of clinical symptoms was quite evident in our case.Figure 1: (a) Pretreatment bilateral upper eyelid swelling, (b) pretreatment bilateral submandibular swelling, (c and d) during glucocorticoid therapy (day 15) resolution of orbital and submandibular swelling, respectivelyFigure 2: Salivary gland with seromucinous acini and ducts embedded in mildly fibrotic stroma with numerous lymphoid follicles with germinal centers (a and b: H and E). Clusters of plasma cells are highlighted with CD138 immunohistochemical stain (c). IgG4 positive cells, >10/hpf (d)IgG4-related disease (IgG4-RD) is a chronic, systemic, fibroinflammatory condition with variable organ manifestation. CD4+ T-cells and B-cells are central to the pathogenesis causing organ damage and fibrosis. Marked expansion of IgG4-secreting plasmablast in the blood is usually seen in active and untreated cases.[1] Key to diagnosis is the classical histopathological hallmarks of lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis. IgG4 RD usually has a good response to steroids but a variable relapse rate. Factors associated with lesser treatment response and relapse were well analyzed in a Japanese multicenter study. Multivariate analysis from the study revealed that intermediate steroid initial dose (0.4–0.69 mg/day), slow tapering regimen (<0.4 mg/day), and shorter disease duration were associated with a significantly lower rate of disease relapse.[2] The study of isolated IgG4 ophthalmic disease also echoed similar results regarding steroid response and relapse, with more relapse in those with elevated serum IgG4 levels and a shorter duration of initial steroid treatment (<5 months). Low-dose steroid maintenance should be considered to avoid recurrence in patients with elevated serum IgG4 levels.[3] Later on, rituximab therapy showed promising results in inducing remission[4] and steroid-free long-term maintenance.[5] Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.