Abstract
Granulomatosis with polyangiitis is an anti-neutrophil cytoplasmic antibody-associated vasculitis that manifests in various ways by affecting the small-sized vessels in multiple organs. Acute pleuritis and pericarditis are both rare among the different manifestations of granulomatosis with polyangiitis. The symptoms in each of the organs are often apparent at the time of diagnosis and tend to diminish with treatment. Organ damage and progression of the disease during treatment are uncommon. We encountered a patient with granulomatosis with polyangiitis who, after starting intravenous methylprednisolone pulse therapy, concurrently developed acute pleuritis and pericarditis. The patient was a 47-year-old Japanese man with myalgia in whom kidney dysfunction, proteinase 3-anti-neutrophil cytoplasmic antibody positivity, and a lung mass were detected. Granulomatosis with polyangiitis was diagnosed pathologically from a lung and a kidney biopsy. Acute pleuritis and pericarditis, which developed after the first course of intravenous methylprednisolone pulse therapy, both resolved following the second course. The present report indicates that secondary serositis such as pleuritis and pericarditis can develop in patients with granulomatosis with polyangiitis even during glucocorticoid therapy.