Retroperitoneal fibrosis and constrictive pericarditis-IgG4 related diseases: A case report.

Retroperitoneal fibrosis (RPF) is a rare disease characterized by infiltration of inflammatory cells and deposition of thickened fibrous tissues. The present study presents the case of a 53-year-old patient treated for generalized weakness and fatigue for 1 year prior to hospitalization. A cardiac ultrasound revealed pericardial effusion that required pericardiocentesis, during which 1,400 ml serous fluid with the characteristics of an exudate was aspirated.