title: Factors associated with treatment failure in vertebral osteomyelitis requiring spinal instrumentation.
abstract: Patients with vertebral osteomyelitis may require instrumentation for spinal stabilization. Determining the optimal duration and type of antimicrobial therapy for these patients is challenging. The aim of this study was to examine risk factors for treatment failure, in particular antimicrobial duration, in a cohort of patients requiring spinal instrumentation for vertebral osteomyelitis. We conducted a retrospective cohort study of all patients with vertebral osteomyelitis who had spinal instrumentation between January 2002 and January 2012 at the University of Maryland Medical Center. The primary outcome measure was treatment failure >4 weeks postoperatively. We identified 131 patients with vertebral osteomyelitis requiring spinal instrumentation, 94 of whom had >4 weeks of follow-up and were included in the primary analysis. Treatment failure occurred in 22 of the 94 patients (23%) at a median of 4 months after surgery. Among patients who failed therapy, 20 of 22 failed within 1 year of surgery. Cervical and thoracic infection sites and the presence of negative cultures were associated with fewer treatment failures. Addition of rifampin and the use of chronic suppressive antimicrobials did not affect treatment failure rate. Twenty-three percent of patients with spinal instrumentation for vertebral osteomyelitis experienced treatment failure. Treatment failure almost always occurred within the first year of spinal instrumentation.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Maryland, Baltimore, Maryland, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Arnold
authors.forename: Clare
authors.initials: C
authors.lastname: Rock
authors.forename: Lindsay
authors.initials: L
authors.lastname: Croft
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Gilliam
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Morgan
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D003646:Debridement; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000601:surgery; D016908:Gram-Positive Bacterial Infections / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D009984:Orthopedic Fixation Devices / Q000382:microbiology*; D010019:Osteomyelitis / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000601:surgery; D012189:Retrospective Studies; D012307:Risk Factors; D013131:Spine / Q000187:drug effects / Q000382:microbiology / Q000601:surgery; D013997:Time Factors; D017211:Treatment Failure
chemical_list: D000900:Anti-Bacterial Agents