Open Access Highly Accessed Research article

Is switching to an oral antibiotic regimen safe after 2 weeks of intravenous treatment for primary bacterial vertebral osteomyelitis?

Baharak Babouee Flury1*, Luigia Elzi1, Marko Kolbe2, Reno Frei3, Maja Weisser1, Stefan Schären4, Andreas F Widmer1 and Manuel Battegay1

Author Affiliations

1 Division of Infectious Diseases and Hospital Epidemiology, University Hospital, Petersgraben 4, Basel 4031, Switzerland

2 Medical Faculty, University of Basel, Basel, Switzerland

3 Division of Clinical Microbiology, University Hospital Basel, Basel, Switzerland

4 Department of Orthopedic Surgery, University Hospital of University Basel, Basel, Switzerland

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BMC Infectious Diseases 2014, 14:226  doi:10.1186/1471-2334-14-226

Published: 27 April 2014



Vertebral osteomyelitis (VO) may lead to disabling neurologic complications. Little evidence exists on optimal antibiotic management.


All patients with primary, non-implant VO, admitted from 2000–2010 were retrospectively analyzed. Patients with endocarditis, immunodeficiency, vertebral implants and surgical site infection following spine surgery were excluded. Persistence of clinical or laboratory signs of inflammation at 1 year were defined as treatment failure. Logistic regression was used to estimate the odds ratios (OR) of switch to an oral regimen after 2 weeks.


Median antibiotic treatment was 8.1 weeks in 61 identified patients. Switch to oral antibiotics was performed in 72% of patients after a median intravenous therapy of 2.7 weeks. Switch to oral therapy was already performed after two weeks in 34% of the patients. A lower CRP at 2 weeks was the only independent predictor for switch to oral therapy (OR 0.7, 95% confidence interval 0.5-0.9, p = 0.041, per 10 mg/l increase). Staphylococcus aureus was the most frequently isolated microorganism (21%). Indications for surgery, other than biopsy, included debridement with drainage of epidural or paravertebral abscess (26 patients; 42%), and CT - guided drainage (3 patients).

During the follow-up, no recurrences were observed but 2 patients died of other reasons than VO, i.e. the 1 year intention to treat success rate was 97%.


Cure rates for non-implant VO were very high with partly short intravenous and overall antibiotic therapy. Switching to an oral antibiotic regimen after two weeks intravenous treatment may be safe, provided that CRP has decreased and epidural or paravertebral abscesses of significant size have been drained.

Vertebral osteomyelitis; Switch to oral therapy; Antibiotic management