[MICROSCOPIC POLYANGIITIS WITH VARIABLE PRESENTATION].

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a group of rare diseases of systemic necrotizing vasculitis affecting small and medium-sized vessels and may be associated with the presence of anti- neutrophil cytoplasmic antibody. Vessels in different organs and systems are involved, leading to various clinical manifestations of the disease. We present 3 cases of microscopic polyangiitis which have been diagnosed and treated in one medical department for over 4 years. The first patient presented with a clinical picture resembling idiopathic pulmonary fibrosis (IPF) and the diagnosis of microscopic polyangiitis (MPA) was established only when acute renal failure appeared. With appropriate therapy, the renal function normalized but her respiratory status deteriorated and she died due to pulmonary infection. The second case presented with constitutional symptoms such as general weakness, weight loss, leg edema and elevated CRP. During the investigation, mononeuritis multiplex and then MPA were diagnosed. She was successfully treated. The third patient diagnosed with MPA presented as end stage renal failure and was treated by cyclophosphamide and rituximab. He did not receive cotrimoxazole that was recommended and was hospitalized for pneumocystis jirovecii pneumonia. Despite intensive therapy in the ICU by various antibiotics and mechanical ventilation, his condition deteriorated and the patient died.