Response to pneumococcal vaccine in interstitial lung disease patients: Influence of systemic immunosuppressive treatment.

BACKGROUND: Interstitial lung diseases (ILD) are severe respiratory diseases, and ILD patients are treated with corticosteroid and immunosuppressive agents. However, it is unclear whether these medications influence the response of pneumococcal vaccine.

OBJECTIVES: We examined the immunogenicity of pneumococcal vaccines (PPSV23 and PCV13) in ILD patients undergoing immunosuppressive treatment.

METHODS: ILD patients who were regularly followed at the outpatient clinic were enrolled. Sera were collected before and 4-8 weeks after vaccination. Serotype-specific immunoglobulin G (IgG) concentrations against pneumococcal serotype 19F were measured by ELISA.

RESULTS: IgG concentrations to serotype 19F were increased in all groups in response to the vaccine. Both PCV13 and PPSV23 induced IgG concentrations in patients immunized for the first time. Response rates for the ILD group were comparable with those for the ILD group undergoing corticosteroid therapy. Only idiopathic pulmonary fibrosis patients undergoing immunosuppressive therapy had a significantly lower response.