Invasive pediatric Kingella kingae Infections: a nationwide collaborative study

Pediatr Infect Dis J. 2010 Jul;29(7):639-43. doi: 10.1097/INF.0b013e3181d57a6c.

Abstract

Background: Kingella kingae is a gram-negative coccobacillus, increasingly recognized as an invasive pediatric pathogen. To date, only few small series of invasive K. kingae infections have been published, mostly from single medical centers. A nationwide multicenter study was performed to investigate the epidemiologic, clinical, and laboratory features of children with culture-proven K. kingae infections.

Methods: Clinical microbiology laboratories serving all 22 medical centers in Israel were contacted in a search for children aged 0 to 18 years from whom K. kingae was isolated from a normally sterile site, dating from as far back as possible until December 31, 2007. Medical records of identified patients were reviewed using uniform case definitions.

Results: A total of 322 episodes of infection were identified in 321 children, of which 96% occurred before the age of 36 months. The annual incidence in children aged <4 years was 9.4 per 100,000. Infections showed a seasonal nadir between February and April. Skeletal system infections occurred in 169 (52.6%) children and included septic arthritis, osteomyelitis, and tenosynovitis. Occult bacteremia occurred in 140 children (43.6%), endocarditis in 8 (2.5%), and pneumonia in 4 (1.2%). With the exception of endocarditis cases, patients usually appeared only mildly ill. About one-quarter of children had a body temperature <38 degrees C, 57.1% had a blood white blood cell count <15,000/mm, 22.0% had normal C-reactive protein values, and 31.8% had nonelevated erythrocyte sedimentation rate.

Conclusions: K. kingae infections usually occur in otherwise healthy children aged 6 to 36 months, mainly causing skeletal system infections and bacteremia, and occasionally endocarditis and pneumonia. Clinical presentation is usually mild, except for endocarditis, necessitating a high index of suspicion.

Publication types

  • Multicenter Study

MeSH terms

  • Adolescent
  • Age Factors
  • Arthritis, Infectious / epidemiology
  • Arthritis, Infectious / microbiology
  • Arthritis, Infectious / pathology
  • Bacteremia / epidemiology
  • Bacteremia / microbiology
  • Bacteremia / pathology
  • Child
  • Child, Preschool
  • Endocarditis, Bacterial / epidemiology
  • Endocarditis, Bacterial / microbiology
  • Endocarditis, Bacterial / pathology
  • Female
  • Humans
  • Incidence
  • Infant
  • Israel / epidemiology
  • Kingella kingae / isolation & purification*
  • Male
  • Neisseriaceae Infections / epidemiology*
  • Neisseriaceae Infections / microbiology
  • Neisseriaceae Infections / pathology*
  • Osteomyelitis / epidemiology
  • Osteomyelitis / microbiology
  • Osteomyelitis / pathology
  • Pneumonia, Bacterial / epidemiology
  • Pneumonia, Bacterial / microbiology
  • Pneumonia, Bacterial / pathology
  • Seasons
  • Tenosynovitis / epidemiology
  • Tenosynovitis / microbiology
  • Tenosynovitis / pathology