title: Invasive pneumococcal infections in children following transplantation in the pneumococcal conjugate vaccine era.
abstract: BACKGROUND
  Pediatric recipients of hematopoietic stem cell and solid organ transplants are at increased risk of invasive pneumococcal infections (IPI). Data on IPI in this population are scarce. To our knowledge, this is the first study describing the epidemiology of IPI among pediatric transplant recipients in the pneumococcal conjugate vaccine (PCV) era.
  
  
  METHODS
  We identified transplant recipients with IPI at 8 children's hospitals in the U.S. from our surveillance database (2000-2014). Pneumococcal isolates were collected prospectively. Serotyping and antibiotic susceptibility were performed in a central laboratory. Categorical variables were analyzed by Fisher's exact test and continuous variables with nonparametric tests. Indirect cohort study design was used to calculate vaccine effectiveness.
  
  
  RESULTS
  We identified 65 episodes of IPI in transplant recipients. Recurrent IPI was observed in 10% of transplant recipients. The IPI crude incidence rate in solid organ transplant recipients was higher than in the general population. Most IPI episodes occurred >6 months after transplantation. Bacteremia and pneumonia were the most common presentations. Meningitis was unusual. No case fatalities were observed. Serotype 19A was the most common serotype (n=10), followed by 6C (n=7). In 2010-2014, 37% of IPI was caused by PCV13 serotypes. Four cases of vaccine breakthrough were identified. Most isolates were susceptible to penicillin and ceftriaxone. Pneumococcal conjugate and polysaccharide immunization rates were low.
  
  
  CONCLUSIONS
  Pediatric transplant recipients remain at increased risk of IPI in the vaccine era. Most cases presented as a late post-transplant infection. The interval between transplantation and IPI may allow adequate time for pneumococcal immunization.
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
authors.forename: Liset
authors.initials: L
authors.lastname: Olarte
authors.affiliation: Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Philana Ling
authors.initials: PL
authors.lastname: Lin
authors.affiliation: Department of Pediatrics, Ohio State University College of Medicine, Columbus, OH, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Barson
authors.affiliation: Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
authors.forename: Jose R
authors.initials: JR
authors.lastname: Romero
authors.affiliation: Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Tina Q
authors.initials: TQ
authors.lastname: Tan
authors.affiliation: Department of Pediatrics, Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Laurence B
authors.initials: LB
authors.lastname: Givner
authors.affiliation: Department of Pediatrics, University of Southern California School of Medicine, Los Angeles, CA, USA.
authors.forename: Jill A
authors.initials: JA
authors.lastname: Hoffman
authors.affiliation: Department of Pediatrics, Rady Children's Hospital San Diego, San Diego, CA, USA.
authors.forename: John S
authors.initials: JS
authors.lastname: Bradley
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
authors.forename: Kristina G
authors.initials: KG
authors.lastname: Hultén
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
authors.forename: Edward O
authors.initials: EO
authors.lastname: Mason
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
authors.forename: Sheldon L
authors.initials: SL
authors.lastname: Kaplan
mesh_terms: D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D016470:Bacteremia / Q000453:epidemiology; D002443:Ceftriaxone / Q000494:pharmacology / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects*; D006801:Humans; D007115:Immunization Schedule; D016867:Immunocompromised Host; D015994:Incidence; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D016377:Organ Transplantation / Q000009:adverse effects*; D010406:Penicillins / Q000494:pharmacology / Q000627:therapeutic use; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000627:therapeutic use*; D011446:Prospective Studies; D012008:Recurrence; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000302:isolation & purification* / Q000502:physiology; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate; D002443:Ceftriaxone
keywords: 
  Streptococcus pneumoniae
  ; pneumococcal disease; pneumococcal vaccine; transplantation