Prognostic factors analysis of patients with rapid progressive interstitial pneumonias treated by direct hemoperfusion with polymyxin B-immobilized fiber column

Background: Rapid progressive interstitial pneumonias (RPIPs) are episodes of acute respiratory worsening with high mortality. Direct hemoperfusion with polymyxin B-immobilized fiber column (PMX-DHP), which was established in Japan for treatment of sepsis, has been shown to improve the respiratory status of patients with ARDS. Recent reports have suggested beneficial effects of PMX-DHP on oxygenation in RPIPs as well. Aimes : To investigate the prognostic factors in patients with RPIPs treated by PMX-DHP. Methods: This retrospective study subjects consisted of 33 patients with RPIPs, including seventeen with IPF, four with NSIP, five with acute interstitial pneumonia, three with Asbestosis, two with collagen vascular diseases associated-IP and two with chronic hypersensitivity pneumonitis. Patients were treated with PMX-DHP once daily for successive two days for 6 hours, concurrently with corticosteroids. Independent predictors of survival were determined using Cox proportional hazards analysis. Results: P/F ratio significantly improved from 144.7 ± 53.4 to 202.3 ± 79.5 just after PMX-DHP (p<0.01). Survival rates after PMX-DHP were 51.5% at 90days, and the hospital discharge rate was 45.4%. We identified four prognostic factors, including age, time from onset to PMX-DHP, KL-6, SP-D. Using ROC analysis, we found useful threshold for age, time from onset to PMX-DHP, KL-6, SP-D, which were 69 years old, 8 days, 1366 U/mL, 331 ng/mL, respectively. Conclusions: In RPIP patients in our cohort, we identified that age, time from onset to PMX-DHP, KL-6, SP-D may be useful for the selection of patients who benefit from PMX-DHP.