DESAFIOS NO DIAGNÓSTICO DA POLIANGEÍTE MICROSCÓPICA: UM RELATO DE CASO

Introduction: Microscopic polyangiitis (MPA) is a rare and potentially fatal vasculitis that affects small vessels, usually associated with neutrophil cytoplasmic antibodies (ANCA) positivity. Its symptoms can be quite nonspecific, which delays the identification of the disease and the initiation of appropriate treatments. Objective: This study aims to report and analyze a complex case of MPA, focusing on the diagnostic and therapeutic challenges faced. Methodology: This is a case study of a 51-year-old patient, initially treated for uveitis and skin lesions, who developed rapidly progressive glomerulonephritis and severe pulmonary complications. Data were collected through documentary analysis of medical records, laboratory tests, and biopsies, and were supplemented with interviews with the attending team. Results: The patient presented with a varied and nonspecific clinical picture, making early diagnosis difficult. Confirmation occurred at a late stage through renal biopsy and immunological markers, with progression to renal failure and alveolar hemorrhage. Despite treatment with pulse therapy and hemodialysis, the patient died. Conclusion: This study highlights the importance of early clinical suspicion and a multidisciplinary approach in MPA. The diversity of manifestations and the lack of specific findings in early stages reinforce the need for systematic diagnostic strategies to improve patient outcomes.