title: Defective antipneumococcal polysaccharide antibody response in children with recurrent respiratory tract infections.
abstract: BACKGROUND
  Recurrent pyogenic infections are known to occur in patients with an impaired response to polysaccharide antigens. We investigated the occurrence of deficient responses to pneumococcal capsular polysaccharides in patients with recurrent respiratory tract and recurrent systemic infections.
  
  
  METHODS
  Forty-five patients, 1.7 to 17.1 years of age, were immunized with 23-valent pneumococcal polysaccharide vaccine. Antibody levels to seven pneumococcal serotypes (3, 4, 6A, 9N, 14, 19F, 23F) were determined by ELISA before and after immunization. In addition, patients received a booster immunization with diphtheria toxoid, tetanus toxoid, and poliomyelitis virus vaccine.
  
  
  RESULTS
  Thirty-five patients had normal serum immunoglobulin levels. Five of these patients (14%) had low antipneumococcal preimmunization antibody levels and failed to respond to pneumococcal vaccination, whereas the response to booster immunization with protein antigens was appropriate. Three patients were younger than 3 years old, and one had a family history of IgG2 deficiency. Low IgG developed in a fifth patient during follow-up. Ten patients had a humoral immunodeficiency. Seven of these patients failed to respond to pneumococcal vaccination.
  
  
  CONCLUSIONS
  We conclude that a defective immune response to polysaccharide antigens in patients requires long-term follow-up to distinguish transient maturational delay from a persistent selective impaired response to polysaccharide antigens, which on occasion may precede the development of humoral immunodeficiency disease.
authors.affiliation: Department of Immunology, University Hospital for Children and Youth, Het Wilhelmina Kinderziekenhuis, Utrecht, The Netherlands.
authors.forename: L A
authors.initials: LA
authors.lastname: Sanders
authors.forename: G T
authors.initials: GT
authors.lastname: Rijkers
authors.forename: W
authors.initials: W
authors.lastname: Kuis
authors.forename: A J
authors.initials: AJ
authors.lastname: Tenbergen-Meekes
authors.forename: B R
authors.initials: BR
authors.lastname: de Graeff-Meeder
authors.forename: I
authors.initials: I
authors.lastname: Hiemstra
authors.forename: B J
authors.initials: BJ
authors.lastname: Zegers
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D000918:Antibody Specificity; D001428:Bacterial Vaccines / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D004168:Diphtheria Toxoid / Q000276:immunology; D022422:Diphtheria-Tetanus Vaccine; D004338:Drug Combinations; D006801:Humans; D007114:Immunization; D007136:Immunoglobulins / Q000097:blood; D007153:Immunologic Deficiency Syndromes / Q000453:epidemiology / Q000276:immunology*; D007223:Infant; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D012008:Recurrence; D012044:Regression Analysis; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013745:Tetanus Toxoid / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D004168:Diphtheria Toxoid; D022422:Diphtheria-Tetanus Vaccine; D004338:Drug Combinations; D007136:Immunoglobulins; D011135:Polysaccharides, Bacterial; D013745:Tetanus Toxoid