title: Pneumococcal polysaccharide vaccination in adults undergoing immunosuppressive treatment for inflammatory diseases--a longitudinal study.
abstract: BACKGROUND
  Patients undergoing immunosuppressive therapy are at increased risk of infection. Community-acquired pneumonia and invasive pneumococcal disease account for substantial morbidity and mortality in this population and may be prevented by vaccination. Ideally, immunization to pneumococcal antigens should take place before the start of immunosuppressive treatment. Often, however, the treatment cannot be delayed. Little is known about the efficacy of pneumococcal vaccines during immunosuppressive treatment. The objectives of this study were to determine the percentage of vaccine-naïve, immunosuppressed adults with inflammatory diseases seroprotected against Streptococcus pneumoniae and to assess factors associated with the immunogenicity, clinical impact and safety of 23-valent pneumococcal polysaccharide vaccine (PPV) in seronegative subjects.
  
  
  METHODS
  This observational study included patients 18 years of age and older who were receiving prednisone ≥20 mg/day or other immunosuppressive drugs. Exclusion criteria were PPV administration in the previous 5 years, intravenous immunoglobulins and pregnancy. Serum immunoglobulin G (IgG) antibody levels against six pneumococcal serotypes were measured. Seropositivity was defined as IgG of 0.5 μg/ml or greater for at least four of six serotypes. Seronegative patients received PPV, and seropositive patients were included as a comparison group. Vaccine response and tolerance were assessed after 4-8 weeks. Disease activity was evaluated on the basis of the Physician Global Assessment scores. Serology was repeated after 1 year, and information on any kind of infection needing medical attention was collected. Outcomes were the proportion of seropositivity and infections between vaccinated and unvaccinated patients.
  
  
  RESULTS
  Of 201 included patients, 35 received high-dose corticosteroids and 181 were given immunosuppressive drugs. Baseline seronegativity in 60 (30%) patients was associated with corticotherapy and lower total IgG. After PPV, disease activity remained unchanged or decreased in 81% of patients, and 87% became seropositive. After 1 year, 67% of vaccinated compared with 90% of observed patients were seropositive (p < 0.001), whereas the rate of infections did not differ between groups. Those still taking prednisone ≥10 mg/day tended to have poorer serological responses and had significantly more infections.
  
  
  CONCLUSIONS
  PPV was safe and moderately effective based on serological response. Seropositivity to pneumococcal antigens significantly reduced the risk of infections. Sustained high-dose corticosteroids were associated with poor vaccine response and more infections.
authors.affiliation: Division of Clinical Immunology and Allergy, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. lara.fischer@chuv.ch.|Division of Dermatology, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. lara.fischer@chuv.ch.
authors.forename: Lara
authors.initials: L
authors.lastname: Fischer
authors.affiliation: Division of Clinical Immunology and Allergy, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. patricia.francis@hcuge.ch.
authors.forename: Patricia Francis
authors.initials: PF
authors.lastname: Gerstel
authors.affiliation: Division of Clinical Epidemiology, Department of Health and Community Medicine, University Hospital and Faculty of Medicine, Geneva, Switzerland. antoine.poncet@hcuge.ch.
authors.forename: Antoine
authors.initials: A
authors.lastname: Poncet
authors.affiliation: Center for Vaccinology, University Hospital and Faculty of Medicine, Geneva, Switzerland. claire-anne.siegrist@unige.ch.
authors.forename: Claire-Anne
authors.initials: CA
authors.lastname: Siegrist
authors.affiliation: Division of Dermatology, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. emmanuel.laffitte@hcuge.ch.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Laffitte
authors.affiliation: Division of Rheumatology, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. cem.gabay@hcuge.ch.
authors.forename: Cem
authors.initials: C
authors.lastname: Gabay
authors.affiliation: Division of Clinical Immunology and Allergy, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. joerg.seebach@hcuge.ch.
authors.forename: Joerg Dieter
authors.initials: JD
authors.lastname: Seebach
authors.affiliation: Division of Clinical Immunology and Allergy, Department of Medical Specialties, University Hospital and Faculty of Medicine, Geneva, Switzerland. camillo.ribi@chuv.ch.|Division of Immunology and Allergy, Lausanne University Hospital CHUV, Lausanne, Switzerland. camillo.ribi@chuv.ch.
authors.forename: Camillo
authors.initials: C
authors.lastname: Ribi
mesh_terms: D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D016867:Immunocompromised Host / Q000187:drug effects* / Q000276:immunology*; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D022242:Pneumococcal Vaccines / Q000276:immunology / Q000627:therapeutic use*
chemical_list: C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007166:Immunosuppressive Agents; D022242:Pneumococcal Vaccines