IgG4-related systemic disease presenting with lung entrapment and constrictive pericarditis.

We describe a 29-year-old woman who presented with chronic pleuropericarditis complicated by lung entrapment and constrictive pericarditis. Pleural biopsy performed during the decortication procedure revealed fibrinous pleuritis with lymphoplasmacytic inflammation including IgG4-positive plasma cells. The patient responded favorably to corticosteroid therapy with resolution of pleural effusion and constrictive physiology. To our knowledge, this is the first reported case of IgG4-related systemic disease manifesting as lung entrapment and constrictive pericarditis.