A Case Report of Pulmonary‐Renal Syndrome Treated With Continuous Hemodiafiltration and Hemodialysis

: This case describes a 40‐year‐old man complaining of general malaise, dyspnea with hemoptysis and anuria. Laboratory data indicated renal failure and the presence of systemic inflammation. His chest radiograph and computed tomography showed bilateral diffuse interstitial alveolar infiltration. These findings indicated acute deterioration of chronic renal dysfunction complicated by interstitial pneumonitis. He initially received daily conventional hemodialysis (HD), an antibiotic and oxygen therapy. However, his renal and pulmonary function continued to deteriorate. Antineutrophil cytoplasm antibodies against myeloperoxidase (MPO‐ANCA) and antibodies against proteinase 3 (PR3‐ANCA) were negative. We suspected that his pulmonary‐renal syndrome was caused by ANCA‐negative vasculitis. We applied mechanical ventilation, pulsed methylprednisolone therapy and continuous hemodiafiltration (CHDF) combined with HD. PaO2/FiO2 ratio and mean pulmonary arterial pressure gradually improved after initiation of CHDF. He was finally separated from mechanical ventilation after 44 days in the hospital. He is currently alive with the support of conventional HD.