Bacteriology of Orthopaedic Infections: 6 mo - 2 yrs



- See:
      - Osteomyelitis Child < 3yrs
      - Septic Hip

- Bacteriology:
    - between ages six months and two years, hemophilus influenza type B is the main pathogen in septic arthritis (30-50 %), followed by Staph aureus and strep;
    - in infants and children 1 month to 3 years old, the predominant organism causing hematogenous septic arthritis historically was haemophilus influenzae, followed by staphylococci and streptococci;
           - predominance of H. influenza has significantly declined since a vaccine has been developed;
           - in the study by Peltola H, et al. (1998), the incidence of haemophilus influenza septic arhtritis was 0% after 10 years of routine vaccination;
                  - Reduced incidence of septic arthritis in children by Haemophilus influenzae type-b vaccination. Implications for treatment.

    - differential dx: (child 3 mo - 6 yrs)
           - S. aureus           
           - H. influ           
           - Streptococci       
           - Enterobacteriaceae


- Lab Studies:
    - only the gram stain and culture are diagnostic of infection;
          - it is therefore imperative that material from direct aspiration of site of infection be obtained;
    - WBC count is unreliable;
    - ESR is useful for diagnosis and for following response to treatment;
    - blood cultures are also useful in diagnosis;


- Treatment:
    - septic hip: emergent drainage;
    - cefuroxime (75-100 mg/kg/day) is the current drug of choice since it provides adequate cerebrospinal fluid levels;
    - septic arthritis secondary to influenzae usually responds very rapidly to treatment;
    - second choice:
           - cefotaxime
           - ceftriaxone
           - timentin



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, November 29, 2012 4:21 pm