673. Bacteremic Staphylococcus aureus osteoarticular infections: Observations on treatment and outcomes in a population with a high prevalence of MRSA
Session: Poster Abstract Session: They've Been Here a Billion Years! Pediatric Bacterial and Viral Infections
Thursday, October 27, 2016
Room: Poster Hall
Posters
  • BOAI poster IDWeek 2016.pdf (438.1 kB)
  • Background: Bacteremia is often one factor used in deciding the need for prolonged intravenous antimicrobial therapy in osteoarticular infections. Studies in populations with a low incidence of MRSA have shown little difference in outcome between osteomyelitis patients with and without bacteremia. We examined treatment practices and outcomes of S. aureus bacteremic osteoarticular infections (BOAI) evaluated at Texas Children’s Hospital (TCH).

    Methods: Cases of acute hematogenous osteomyelitis or septic arthritis in children with positive blood cultures for S. aureus at TCH from 2011-2014 were reviewed. Orthopedic complications included chronic osteomyelitis, growth arrest, pathologic fracture, avascular necrosis and chronic dislocation. Acute kidney injury (AKI) was defined as a doubling of the baseline creatinine.

    Results: 102 cases were included (35 MRSA). Orthopedic complications developed in 18 patients (17.6%). Patients with MRSA had a longer duration of fever (7.5 vs. 4 days, p<0.001), bacteremia and length of stay, more frequent abscesses (68.6% vs. 34.3%, p=0.002) and repeat surgical procedures (62.9% vs. 16.4%, p<0.001). 25 patients (4 MRSA) were discharged home on oral antibiotics. Patients discharged on oral antibiotics had a shorter duration of fever (3 vs. 6 days, p=0.03), a more rapid decline in C-reactive protein (p=0.02), smaller abscesses (p=0.05) and less often had MRSA (16% vs. 40.3%, p=0.03). The frequency of orthopedic complications did not increase in patients who received early transition to oral antibiotics. For patients with MRSA bacteremia the median duration of vancomycin was 6.5 days (IQR: 4-23); the rates of complications between those who received ≥ 7 days vs. < 7 days of vancomycin did not differ. Vancomycin serum troughs > 15 µg/ml were not associated with a decreased duration of fever, bacteremia or hospitalization, need for repeat operation or orthopedic complications but were associated with AKI (57.1%, p=0.001).

    Conclusion: S. aureus BOAI are associated with substantial morbidity. Early transition to oral therapy may be a safe option for select patients with S. aureus BOAI, including those due to MRSA. Prolonged courses of vancomycin and elevated vancomycin troughs were not associated with improved outcomes for MRSA OAI. Prospective studies are necessary to determine optimal management of S. aureus BOAI.

    Jonathon Mcneil, MD1, Kristina G. Hulten, PhD2, Edward O. Mason Jr., PhD, FIDSA2, Sheldon L. Kaplan, MD, FIDSA2 and Jesus G. Vallejo, MD, FIDSA3, (1)Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, Houston, TX, (2)Baylor College of Medicine and Texas Children's Hospital, Houston, TX, (3)Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, TX

    Disclosures:

    J. Mcneil, Forest Labs: Grant Investigator , Research grant and Site-Co-investigator on clinical trial that is unrelated to research presented

    K. G. Hulten, None

    E. O. Mason Jr., None

    S. L. Kaplan, Forest Labs: Grant Investigator , Research support and Site-PI for clinical trial unrelated to presented research
    Pfizer: Grant Investigator , Research grant
    Cubist: Grant Investigator , Research grant and Site-PI for clinical trial unrelated to presented research

    J. G. Vallejo, Forest Labs: Grant Investigator , Research grant and Site-Co-investigator on clinical trial that is unrelated to research presented

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.