RT Journal Article SR Electronic T1 Selection of an Appropriate Empiric Antibiotic Regimen in Culture-Negative Hematogenous Vertebral Osteomyelitis JF bioRxiv FD Cold Spring Harbor Laboratory SP 363549 DO 10.1101/363549 A1 Ki-Ho Park A1 Dong Youn Kim A1 Yu-Mi Lee A1 Mi Suk Lee A1 Kyung-Chung Kang A1 Jung Hee Lee A1 Seong Yeon Park A1 Chisook Moon A1 Yong Pil Chong A1 Sung-Han Kim A1 Sang-Oh Lee A1 Sang-Ho Choi A1 Yang Soo Kim A1 Jun Hee Woo A1 In-Gyu Bae A1 Oh-Hyun Cho YR 2018 UL http://biorxiv.org/content/early/2018/07/11/363549.abstract AB The aim of this study was to determine which antibiotic combinations are appropriate for culture-negative hematogenous vertebral osteomyelitis (HVO), based on the antibiotic-susceptibility pattern of organisms isolated from cases of culture-proven HVO. We conducted a retrospective chart review of adult patients with microbiologically proven HVO in five tertiary-care hospitals over a 7-year period. The appropriateness of empiric antibiotic regimens was assessed based on the antibiotic susceptibility profiles of isolated bacteria. In total, 358 cases of microbiologically proven HVO were identified. The main causative pathogens identified were methicillin-susceptible Staphylococcus aureus (33.5%), followed by methicillin-resistant S. aureus (MRSA) (24.9%), aerobic gram-negative bacteria (21.8%), and Streptococcus species (11.7%). Extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and anaerobes accounted for only 1.7% and 1.4%, respectively, of the causative pathogens. Based on the susceptibility results of isolated organisms, levofloxacin plus rifampicin was appropriate in 73.5%, levofloxacin plus clindamycin in 71.2%, and amoxicillin-clavulanate plus ciprofloxacin in 64.5% of cases. These oral combinations were more appropriate for treating community-acquired HVO (85.8%, 84.0%, and 80.4%, respectively) than healthcare-associated HVO (52.6%, 49.6%, and 37.6%, respectively). Vancomycin combined with ciprofloxacin, ceftriaxone, ceftazidime, or cefepime was similarly appropriate (susceptibility rates of 93.0%, 94.1%, 95.8%, and 95.8%, respectively). In conclusion, in a setting with a high prevalence of MRSA HVO, oral antibiotic combinations may be suboptimal for treatment of culture-negative HVO and should be used only in patients with community-acquired HVO. Vancomycin combined with fluoroquinolone or a broad-spectrum cephalosporin was appropriate in most cases of HVO in this study.