Abstract
Double-positive disease, defined by double-seropositivity for serum anti-glomerular basement membrane (GBM) antibodies and anti-neutrophil cytoplasmic antibodies (ANCA) is a rare cause of pulmonary-renal syndrome. Here, we present an exceptional course of a 20-year-old male with seropositivity for anti-myeloperoxidase anti-neutrophil cytoplasmic antibodies and anti-GBM antibody, who presented first with renal impairment due to focal necrotizing crescentic glomerulonephritis. After receiving treatment, he presented two years later with a relapse manifesting with diffuse alveolar hemorrhage and multiple splenic infarcts. We discuss the clinical presentation patterns and treatment strategies of this entity.