Immunoglobulin G4-related lung disease in an adolescent patient

Abstract

Immunoglobulin G4-related disease is a recently recognized systemic immune-mediated condition characterized by lymphoplasmacytic infiltrate in various organs with IgG4 positive plasma cells. Isolated lung involvement is rare, difficult to diagnose and can mimic primary lung malignancy on imaging. We report the case of an isolated IgG4-related interstitial lung disease in a 16-year-old asymptomatic male adolescent with incidentally found bilateral nodular lesions by chest radiograph. The patient underwent surgical interventions for assumption of malignancy. Serum IgG4 levels was normal. Нistological examination revealed significant lymphoplasmacytic infiltrate with lymphoid follicle formation, peribronchial fibrosis, vascular obliteration. Prominent interstitial IgG4 positive plasma cell infiltrate was identified by immunohistochemistry. Isolated IgG4-related lung disease should be taken into account as a possible differential diagnosis of mass-forming lesions, even when no other organ manifestation is clinically apparent at the time of diagnosis.