IgG4-related disease in pediatric patients: a single-center experience

Objective Immunoglobulin G4-related disease (IgG4-RD) is a systemic, immune-mediated, and fibroinflammatory disease that can affect almost any organ system. We aimed to present our single-center experience of pediatric patients with IgG4-RD, a rare disease in children. Methods Pediatric patients diagnosed with IgG4-RD at the Hacettepe University between June 2014 and September 2020 were evaluated retrospectively. Patients with definite, probable, or possible diagnosis of IgG4-RD were included. Results A total of eight patients with a median age of 13.4 (IQR 9.5–15.0) years were included in the study. Clinical presentations were IgG4-related ophthalmic disease in six patients, IgG4-related lymphadenopathy in one patient, and IgG4-related sialadenitis and lymphadenopathy of several lymph nodes accompanied by pancreatitis, ulcerative colitis, and pulmonary manifestations in one patient. Elevated serum IgG4 was detected in three of eight patients (37.5%). The main histopathological feature was fibrosis and lymphoplasmacytic infiltrates. Corticosteroids were used as first-line treatment in almost all patients with or without steroid-sparing agents. Azathioprine, methotrexate and rituximab were used as steroid-sparing agents. Relapse occurred in two of seven patients. Radiotherapy was used as the last resort in one patient with severe orbital disease. Conclusion IgG4 RD mainly presents with orbital manifestations in pediatric population but has wide phenotypic clinical variability. Although rare, early recognition and treatment are essential for a better outcome in these patients.