189. Risk Factors and Outcomes of Hematogenous Vertebral Osteomyelitis in Patients with staphylococcus Aureus Bacteremia: Results from a 20-year Prospective Cohort

BACKGROUND: Hematogenous vertebral osteomyelitis (HVOM) is a rare, but devastating complication of Staphylococcus aureus bacteremia (SAB). Risk factors and outcomes associated with HVOM among patients with SAB remain incompletely understood. METHODS: All adult, hospitalized, non-neutropenic patients with SAB were prospectively enrolled from 1995 to 2015. Additional data was subsequently collected on all patients with HVOM. Diagnosis of HVOM was made either radiographically or microbiologically by culture from the infection site. Patients who underwent lumbar puncture or spinal surgery within 30 days prior to the diagnosis of HVOM were excluded. RESULTS: Of 2,475 cases of prospectively enrolled patients with SAB, 90 (3.6%) developed HVOM. The most common site of involvement was the lumbar spine (65.6%). MRI was used in the diagnosis of 90% of patients and although only 28.9% underwent bone biopsy, 88.5% of these bone cultures grew S. aureus. Patients with HVOM were more likely to have community-acquired SAB (22.2% vs. 9.9%, P < 0.0001) and persistent bacteremia (47.8% vs. 20.5%, P < 0.0001). Patients with HVOM who required surgical intervention were more likely to have motor deficit (60.9% vs. 21.4%, P = 0.0013) and have associated epidural abscesses (69.6% vs. 44.8%, P = 0.0400). Prolonged antibiotic use for HVOM was common, with 13.3% remaining on therapeutic antibiotics and 16.6% on suppressive therapy at 6 months. This dropped to 2.2% on therapeutic and 15.5% on suppressive therapy at 12 months. All-cause mortality was high in the HVOM cohort at 14.4% at 90-days, increasing to a cumulative 18.9% and 20.0% at 6 and 12-months, respectively. Rates of readmission, recurrent bacteremia, paralysis, and mortality at 6 and 12-months were similar for those who required surgical intervention and those who did not. Demographics, comorbidities, and clinical characteristics of patients with and without hematogenous vertebral osteomyelitis (HVOM) [Image: see text] CONCLUSION: HVOM in patients with SAB was associated with high rates of all-cause mortality up to 12 months following date of diagnosis. Patients with community-acquired bacteremia and persistent bacteremia were more likely to develop HVOM. DISCLOSURES: Vance G. Fowler, Jr., MD, MHS, Achaogen (Consultant)Actavis (Grant/Research Support)Advanced Liquid Logics (Grant/Research Support)Affinergy (Consultant, Research Grant or Support)Affinium (Consultant)Allergan (Grant/Research Support)Ampliphi Biosciences (Consultant)Basilea (Consultant, Research Grant or Support)Bayer (Consultant)C3J (Consultant)Cerexa (Consultant, Research Grant or Support)Contrafect (Consultant, Research Grant or Support)Cubist (Grant/Research Support)Debiopharm (Consultant)Destiny (Consultant)Durata (Consultant)Forest (Grant/Research Support)Genentech (Consultant, Research Grant or Support)Integrated Biotherapeutics (Consultant)Janssen (Consultant, Research Grant or Support)Karius (Grant/Research Support)Locus (Grant/Research Support)Medical Biosurfaces (Grant/Research Support)Medicines Co. (Consultant)Medimmune (Consultant, Research Grant or Support)Merck (Consultant, Research Grant or Support)NIH (Grant/Research Support)Novadigm (Consultant)Novartis (Consultant, Research Grant or Support)Pfizer (Grant/Research Support)Regeneron (Consultant, Research Grant or Support)Tetraphase (Consultant)Theravance (Consultant, Research Grant or Support)Trius (Consultant)xBiotech (Consultant)