Objective: IgG4-related disease (IgG4-RD) is characterized by IgG4-positive plasmacytic infiltration and fibrosis in various organs. Orbital involvement in IgG4-RD includes lacrimal glands, extra-ocular muscles, trigeminal nerve and other parts of the orbit. Immunohistochemical staining is used to diagnose IgG4-RD in patients with orbital inflammation. The purpose of this retrospective study was to clarify the clinicopathological features of IgG4-RD complicated with orbital involvement.
Methods: We examined the clinical features, pathological findings and response to treatment in nine patients with IgG4-RD who underwent orbital tissue biopsy between April 2010 and August 2012 at the University of Tsukuba Hospital.
Results: Among the nine patients, eight had dacryoadenitis, one had infraorbital nerve swelling, and another one had IgG4-related orbital inflammation. Involvement of other organs was identified in all patients, including involvement of the salivary glands, lymph nodes, lung, kidney and para-aorta. In all patients, biopsy samples from orbital tissues showed lymphoplasmacytic infiltration and fibrosis, and IgG4-positive/IgG-positive plasmacyte ratio of > 40%. All patients were treated with prednisolone (0.6 mg/kg/day) and responded well in early phase, although relapse was noted in two patients following tapering of prednisolone, evident by swelling of lacrimal glands.
Conclusion: Patients with IgG4-RD complicated with orbital involvement often present with involvement of other organs. The histopathological findings of orbital tissue match the characteristic features of IgG4-RD. Corticosteroid is effective for orbital and systemic involvement in IgG4-RD.