IgG4 related disease in pediatrics

Immunoglobulin G4 (IgG4)-related disease is a recently described entity that can affect almost any organ. Its diagnosis is based on the correlation of clinical, laboratory, and immunohistopathological findings. It is considered a rare disease in pediatrics, characterized by lymphoplasmacytic infiltration with an increased number of IgG4 cells, which can affect different organs, causing swelling and progressive fibrosis. We present the case of a pediatric patient, as this disease has been described primarily in adults and is therefore generally unknown to pediatricians.