A Rare Case of Pulmonary-Renal Syndrome With Triple-Seropositive for Myeloperoxidase-Anti-Neutrophil Cytoplasm Antibody (MPO-ANCA), Proteinase 3 (PR3)-ANCA and Anti-Glomerular Basement Membrane (GBM) Antibodies

Anti-glomerular basement membrane (anti-GBM) disease and anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis are the main causes of pulmonary-renal syndrome (PRS). The concurrence of both ANCA - myeloperoxidase (MPO) and proteinase 3 (PR3) - and anti-GBM antibodies has been described, although positivity for all three antibodies has rarely been reported. The natural history of triple-positive patients as well as the best therapeutic approach remains unknown. We describe a case of an 80-year-old woman that presented to the emergency department with a 3-month history of progressive fatigue, malaise and anorexia, and 5 weeks of cough with blood-streaked sputum and progressive peripheral edema. Through the complementary study, a rare diagnosis of PRS with triple-seropositive for both ANCA (MPO and PR3) and anti-GBM antibodies was made in a patient with untreated chronic hepatitis B virus infection. She was treated with glucocorticoid, cyclophosphamide, plasma exchange and entecavir, with pulmonary recovery. Renal function did not improve. After 2 years, the patient is still in dialysis, but did not have relapse of alveolar hemorrhage and ANCA and anti-GBM antibody titers remain negative. The authors intend to warn to PRS, in particular this rare cause, since delaying diagnosis can lead to significant morbidity and mortality for patients.