title: Unusually severe cases of Kingella kingae osteoarticular infections in children.
abstract: BACKGROUND
  With the development of molecular biology and specific polymerase chain reaction, Kingella kingae has become the primary diagnosis of osteoarticular infections in young children. Clinical features of these osteoarticular infections are typically mild, and outcome is almost always favorable. We report a series of unusually severe cases of K. kingae osteoarticular infections.
  
  
  METHODS
  All patients with severe osteoarticular infections at presentation were reviewed retrospectively in 2 European pediatric centers. K. kingae was identified using real-time polymerase chain reaction in blood, fluid joint or osseous samples. Clinical, laboratory tests and radiographic data during hospitalization and follow-up were analyzed.
  
  
  RESULTS
  Ten children (mean age 21 ± 12 months) with severe osteoarticular infections caused by K. kingae were identified between 2008 and 2011. Diagnostic delay averaged 13.2 ± 8 days. Only 1 patient was febrile at admission, and 50% children had normal C-reactive protein values (≤10 mg/dL) at presentation. Surgical treatment was performed in all cases. Intravenous antibiotic therapy by cephalosporins for an average of 8 ± 6 days was followed by oral treatment for 27 ± 6 days. Mean follow-up was 24.8 ± 9 months, and satisfactory outcomes were reported in all cases. Two patients (20%) developed a central epiphysiodesis of the proximal humerus during follow-up, but without significant clinical consequence for the moment.
  
  
  CONCLUSIONS
  Because of their mild clinical features at onset, diagnosis of K. kingae osteoarticular infections can be delayed. Care should be taken for early detection and treatment of these infections because bony lytic lesions and potentially definitive growth cartilage damage can occur.
authors.affiliation: From the *Pediatric Orthopedic Department, Robert Debré University Hospital, Paris, France; †Pediatric Orthopedic Department, University Hospital of Geneva, Geneva, Switzerland; ‡Pediatric Department; and §Microbiology Department, Robert Debré University Hospital, Paris, France.
authors.forename: Cindy
authors.initials: C
authors.lastname: Mallet
authors.forename: Dimitri
authors.initials: D
authors.lastname: Ceroni
authors.forename: Estelle
authors.initials: E
authors.lastname: Litzelmann
authors.forename: Victor
authors.initials: V
authors.lastname: Dubois-Ferriere
authors.forename: Mathie
authors.initials: M
authors.lastname: Lorrot
authors.forename: Stéphane
authors.initials: S
authors.lastname: Bonacorsi
authors.forename: Keyvan
authors.initials: K
authors.lastname: Mazda
authors.forename: Brice
authors.initials: B
authors.lastname: Ilharreborde
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001850:Bone Diseases, Infectious / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology* / Q000628:therapy; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D017882:Kingella kingae / Q000302:isolation & purification*; D008297:Male; D016870:Neisseriaceae Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology* / Q000628:therapy; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents