Objectives

Staphylococcus aureus is the most common cause of pyogenic vertebral osteomyelitis (VO). Studies indicate that S. aureus VO results in poor outcome. We aimed to investigate risk factors for treatment failure in patients with Staphylococcus aureus bloodstream infection (SAB) and VO.

Methods

We conducted a post hoc-analysis of data from a German bi-center prospective SAB cohort (2006–2014). Patients were followed-up for one year. Primary outcome was treatment failure defined as relapse and/or death within one year.

Results

A total of 1069 patients with SAB were analyzed, with 92 VO patients. In addition to antibiotic treatment, surgery was performed in 60/92 patients. Treatment failed in 44/92 patients (death, n = 42; relapse, n = 2). Multivariable analysis revealed higher age (HR 1.04 [per year], 95%CI 1.01–1.07), Charlson comorbidity index (HR 1.20, 95%CI 1.06–1.36), presence of neurologic deficits (HR 2.53, 95%CI 1.15–5.53) and local abscess formation (HR 3.35, 95%CI 1.39–8.04) as independent risk factors for treatment failure. In contrast, surgery seemed to be associated with a favourable outcome (HR 0.45 (95%CI 0.20–0.997)).

Conclusion

SAB patients with VO exhibit a high treatment failure rate. Red flags are older age, comorbidities, neurologic deficits and local abscess formation. Whether these patients benefit from intensified treatment (e.g. radical surgery, prolongation of antibiotics) should be investigated further.

Background/Objectives The incidence of vertebral osteomyelitis (VO) has increased over the last years. Estimates from France for 2002/2003 from national hospital-discharge data showed an overall incidence of 2.3/100 000 with an increase with age: 0.3/100 000 (70 years) 1 Grammatico L. Baron S. Rusch E. Lepage B. Surer N. Desenclos J.C. et al. Epidemiology of vertebral osteomyelitis (VO) in France: analysis of hospital-discharge data 2002-2003.

Epidemiol Infect. 2008; 136: 653-660

. Incidence increased from 2.2 to 5.8 per 100 000 person-years over 1995–2008 in Denmark Kehrer et al. (2014). Likewise in Japan increasing incidences have been reported from 5.3 to 7.4 per 100 000 population per year over 2007–2010 (Akiyama et al. 2013) []. This increase is presumably due to an aging population with chronic comorbidities, a growing number of immunosuppressed patients, invasive procedures in vulnerable populations, and better diagnostics (Kehrer et al. 2014).