title: Serious infections in systemic lupus erythematosus with a focus on pneumococcal infections.
abstract: BACKGROUND
  Infections are important denominators of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Pneumococcus pneumoniae has been identified as a relatively frequent cause of serious infections in SLE and vaccination against this pathogen is possible. We analysed the incidence of serious infections in a cohort of SLE patients, focussing on Streptococcus pneumoniae.
  
  
  METHODS
  We retrospectively screened the medical records of all SLE patients who were regularly seen in the outpatient clinic of our department between January 2010 and December 2012. We registered all infections that necessitated admission to the hospital (serious infection) and compared relevant clinical and laboratory parameters and immunomodulating/immunosuppressive treatment in patients with and without serious infections.
  
  
  RESULTS
  In the total cohort of 260 patients, there were 132 episodes of serious infection in 70 patients, with a median follow-up per patient of 11.4 years (range 0 to 50.2 years). S. pneumoniae accounted for 11/132 (8.3%) serious infection episodes and eight of 11 episodes were invasive. With a follow-up of 3970.6 years for the total cohort, this leads to an incidence of 201/100.000 patient-years. In the multivariate analysis neither clinical parameters nor use of immunosuppressive drugs correlated with occurrence of serious infections.
  
  
  CONCLUSIONS
  Compared to the incidence of invasive pneumococcal infections in the Dutch population (15.6/100.000 patient years), the incidence in SLE patients is 13 times higher. This, in combination with the absence of a relation to use of immunosuppressive drugs, is a strong argument to recommend vaccination against S. pneumoniae in all SLE patients.
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, The Netherlands r.luijten@umcutrecht.nl.
authors: R K M A C
authors: RK
authors: Luijten
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, The Netherlands.
authors: B V J
authors: BV
authors: Cuppen
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, The Netherlands.
authors: J W J
authors: JW
authors: Bijlsma
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, The Netherlands.
authors: R H W M
authors: RH
authors: Derksen
mesh_terms: D000293:Adolescent; D000328:Adult; D004927:Escherichia coli Infections / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D015994:Incidence; D007239:Infections / Q000453:epidemiology*; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D011018:Pneumonia, Pneumococcal / Q000453:epidemiology*; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000453:epidemiology*; D013211:Staphylococcus aureus; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents
keywords: Systemic lupus erythematosus; infections; vaccination