Invasive Kingella kingae infections in children: clinical and laboratory characteristics

Pediatrics. 2008 Dec;122(6):1305-9. doi: 10.1542/peds.2007-3070.

Abstract

Objective: Kingella kingae, a Gram-negative coccobacillus, is being increasingly recognized as an invasive pathogen in children, causing mainly bacteremia and arthritis; however, there have been only a few studies on K kingae infections to date, mostly small-scale series. The aim of this study was to report our experience with invasive K kingae infections in children who were hospitalized at a major tertiary medical center in Israel.

Methods: The medical charts of 62 children with proven invasive K kingae infections were reviewed: 42 with positive blood culture results and 20 with positive synovial fluid culture results.

Results: Most infections occurred among previously healthy children aged 5 to 22 months. Eighty percent had a mild concurrent illness of the respiratory or gastrointestinal tract. A chronic underlying disease was documented in 19% of the 1- to 15-year-old children with bacteremia. Three patients had persistent bacteremia, identified by 2 positive blood cultures drawn 1 to 4 days apart. Four (10%) patients from the bacteremia group had endocarditis, and 2 required emergency cardiac surgery. Only a mild-to-moderate elevation of serum inflammatory markers was noted except for patients with endocarditis or a prolonged course of arthritis. Patients with bacteremia received a diagnosis significantly later than those with arthritis, with no other between-group differences in age, month of disease onset, and inflammatory marker levels. All K kingae isolates were resistant to vancomycin and clindamycin.

Conclusions: Our large series indicates that invasive K kingae infections occur in previously healthy children, mostly during the first 2 years of life; affected older children usually have an underlying medical condition. The infection generally elicits only a mild inflammatory response unless accompanied by endocarditis. Despite its low virulence, K kingae might cause a life-threatening heart disease that requires emergent, aggressive treatment.

MeSH terms

  • Adolescent
  • Age Distribution
  • Anti-Bacterial Agents / therapeutic use
  • Arthritis, Infectious / diagnosis
  • Arthritis, Infectious / drug therapy
  • Arthritis, Infectious / epidemiology*
  • Bacteremia / diagnosis
  • Bacteremia / drug therapy
  • Bacteremia / epidemiology*
  • Child
  • Child, Preschool
  • Cohort Studies
  • Endocarditis, Bacterial / diagnosis
  • Endocarditis, Bacterial / drug therapy
  • Endocarditis, Bacterial / epidemiology*
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Infant
  • Israel / epidemiology
  • Kingella kingae / isolation & purification*
  • Linear Models
  • Male
  • Microbial Sensitivity Tests
  • Neisseriaceae Infections / diagnosis
  • Neisseriaceae Infections / drug therapy
  • Neisseriaceae Infections / epidemiology*
  • Probability
  • Retrospective Studies
  • Risk Assessment
  • Severity of Illness Index
  • Sex Distribution
  • Statistics, Nonparametric
  • Treatment Outcome

Substances

  • Anti-Bacterial Agents