title: Primary epiphyseal or apophyseal subacute osteomyelitis in the pediatric population: a report of fourteen cases and a systematic review of the literature.
abstract: BACKGROUND
  Primary epiphyseal or apophyseal subacute osteomyelitis (PEASAO) is a rare condition that typically has mild symptoms and lack of a systemic reaction, according to opinions, case reports, and case series. We reviewed fourteen consecutive cases of PEASAO treated at our institution over a thirteen-year period to characterize this disorder.
  
  
  METHODS
  We retrospectively reviewed the medical records of all children and adolescents who had been surgically managed for PEASAO at our institution from January 2000 to December 2012. A systematic review of the literature was also performed to identify trends in causative organisms and formulate evidence-based recommendations for diagnosis and treatment.
  
  
  RESULTS
  Fourteen children (median age, 27.8 months) with PEASAO were included in the study. Fever (rectal temperature, >38°C) was present at admission in two children, C-reactive protein was within the normal range (<10 mg/dL) in eleven, the erythrocyte sedimentation rate was >20 mm/hr in eight, and the white blood-cell count was normal in all. The pathogen was not identified on blood cultures in any child and was identified on classical cultures of bone samples in only one. Use of PCR (polymerase chain reaction) assays allowed the pathogen to be identified in an additional eight children. The pathogen was Kingella kingae in eight and methicillin-sensitive Staphylococcus aureus in one.
  
  
  CONCLUSIONS
  The use of organism-specific real-time PCR assays markedly improves the detection rate of the pathogen responsible for PEASAO, and K. kingae is the most commonly detected pathogen. The literature highlights a biphasic age distribution of PEASAO in children. The infantile form affects children from one to less than four years of age, accounting for approximately 75% of all PEASAO cases. The second form, in older children, is more likely to be associated with fever and systemic symptoms. The femur and the tibia are the most commonly affected long bones. Laboratory data are usually noncontributory for diagnosing PEASAO, and blood cultures are often sterile. Although K. kingae is the most commonly detected microorganism in children less than four years of age, S. aureus is responsible for most PEASAO in older children. Antibiotic treatment is usually sufficient to eradicate the pathogen.
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Ceroni
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Wilson
authors.initials: W
authors.lastname: Belaieff
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Abdessalam
authors.initials: A
authors.lastname: Cherkaoui
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Pierre
authors.initials: P
authors.lastname: Lascombes
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Jacques
authors.initials: J
authors.lastname: Schrenzel
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Geraldo
authors.initials: G
authors.lastname: de Coulon
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Victor
authors.initials: V
authors.lastname: Dubois-Ferrière
authors.affiliation: Pediatric Orthopedic Service (D.C., W.B., P.L., G.d.C., V.D.-F., and R.D.) and Clinical Microbiology Laboratory, Service of Infectious Diseases (A.C. and J.S.), University Hospitals of Geneva, 6 rue Willy Donzé, CH-1211 Geneva 14, Switzerland. E-mail address for D. Ceroni: dimitri.ceroni@hcuge.ch.
authors.forename: Romain
authors.initials: R
authors.lastname: Dayer
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D017882:Kingella kingae / Q000302:isolation & purification; D008297:Male; D016870:Neisseriaceae Infections / Q000175:diagnosis / Q000601:surgery; D010019:Osteomyelitis / Q000175:diagnosis / Q000382:microbiology* / Q000601:surgery; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000601:surgery; D013211:Staphylococcus aureus / Q000302:isolation & purification