title: C-reactive protein and interleukin-6 levels in the early detection of infection after open fractures.
abstract: OBJECTIVE
  To measure C-reactive protein (CRP) and interleukin-6 (IL-6) levels in 30 patients with open fractures and correlate the levels with infection.
  
  
  METHODS
  29 men and one woman aged 9 to 70 (mean, 37) years presented with open fractures of the upper or lower extremity within 12 hours of injury and underwent debridement and external fixation 3 to 40 (mean, 16) hours after injury. Serum CRP and IL-6 concentrations were measured preoperatively and on postoperative days 2 and 4. CRP was measured using latex agglutination and nephelometry, and IL-6 by enzyme-linked immunosorbent assay. The mean CRP and IL-6 levels in infected and non-infected patients were compared. The trend of CRP and IL-6 levels within the infected group was analysed. Correlations between CRP and infection, and between IL-6 and infection were analysed.
  
  
  RESULTS
  11 of the 30 patients developed wound infection. The day-2 CRP levels of 30 patients were positive (range, 7-28 µg/ml). In 27 patients, the CRP levels were higher on day 2 than preoperation. On day 4, CRP levels declined sharply in patients without infection (mean, 8 µg/ml) but were persistently elevated in patients with infection (mean, 17 µg/ml). The sensitivity and specificity of the CRP test were 100% and 42%, respectively. In the 11 patients with infection, the IL-6 concentrations were elevated at day 2 (mean, 689 pg/ml) and decreased progressively at day 4 (mean, 175 pg/ml). The sensitivity and specificity of the IL-6 test were 90% and 100%, respectively. Infection correlated with CRP and IL-6 levels.
  
  
  CONCLUSIONS
  Serial serum measurements of IL-6 and CRP levels help in the early diagnosis of infections after open fractures before they are clinically evident.
authors.affiliation: Departments of Orthopaedics and Microbiology, Jawaharlal Institute of Post Graduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: Balaji
authors.initials: B
authors.lastname: Douraiswami
authors.forename: Patro K
authors.initials: PK
authors.lastname: Dilip
authors.forename: B N
authors.initials: BN
authors.lastname: Harish
authors.forename: Menon
authors.initials: M
authors.lastname: Jagdish
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002097:C-Reactive Protein / Q000032:analysis*; D003646:Debridement; D016267:External Fixators; D005260:Female; D005592:Fracture Fixation; D005597:Fractures, Open / Q000097:blood* / Q000150:complications / Q000601:surgery*; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D007841:Latex Fixation Tests; D035002:Lower Extremity / Q000293:injuries; D008297:Male; D008875:Middle Aged; D009391:Nephelometry and Turbidimetry; D013530:Surgical Wound Infection / Q000175:diagnosis*; D013997:Time Factors; D034941:Upper Extremity / Q000293:injuries; D055815:Young Adult
chemical_list: D015850:Interleukin-6; D002097:C-Reactive Protein