High-dose prednisolone after intravenous methylprednisolone improves prognosis of acute exacerbation in idiopathic interstitial pneumonias

Background and objective Acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) (AE-IPF) is a poor prognostic disorder. AE is also reported to occur in other idiopathic interstitial pneumonias (IIPs). There are limited data available regarding the effectiveness of treatment for AE-IIPs. The objective of this study was to clarify the prognostic impact of the initial dose of prednisolone (PSL) for treating AE-IIPs. Methods Eighty-five patients with AE-IIPs, diagnosed according to the criteria of the Japanese Respiratory Society, were enrolled in this study (IPF/non-IPF: 63/22 patients) from 2004 to 2013. We performed multivariate Cox proportional hazard regression analysis to identify poor prognostic factors. HRCT patterns at the onset of AE-IIPs were classified as diffuse or non-diffuse. We evaluated the prognostic significance of the initial dose of PSL by adjusting for other prognostic factors. Results Median survival time (MST) after AE-IIPs diagnosis was 49 days. MST of AE-IPF and AE-non-IPF was 39 and 49 days, respectively. A diffuse HRCT pattern, lower serum IgG and higher serum surfactant protein-D at AE diagnosis, long-term oxygen therapy (LTOT) before AE and positive pressure ventilation (PPV) use for AE were significant poor prognostic factors for all patients, as were LTOT before AE and lower serum IgG for no-PPV patients. High-dose PSL ≥ 0.6 mg/kg was a significant prognostic factor for no-PPV patients after adjusting for other prognostic factors. Conclusion We concluded that a dose of PSL ≥ 0.6 mg/kg after i.v. high-dose methylprednisolone therapy should be recommended for the treatment of AE-IIPs.