Bacteraemia and subsequent vertebral osteomyelitis: a retrospective review of 125 patients

Background: Vertebral osteomyelitis (VO) is associated with considerable morbidity and its incidence seems to be increasing. Haematogenous spread is an important aetiological factor. Aim: The objective was to describe a series of patients with VO and to search for a relationship between preceding bacteraemia and subsequent VO with the same pathogen. Design and methods: A retrospective study of all treated cases of VO in a tertiary hospital over a 10-year period. Results: There were 129 cases of VO (involving 125 patients) that received antimicrobial treatment. Eighty-three (66%) were male and the mean age was 59.5 years (range 1 month to 87 years). The vertebral level involved was lumbar in 66 (53%) cases and thoracic in 35 (28%) cases. Seventy-four cases (59%) had a microbiologically confirmed aetiology. The diagnostic yield from procedures was 46 and 36% from blood culture and bone biopsy, respectively. Staphylococcus aureus was the most common pathogen [38 of 74 (51%) cases]. Nine of 38 (24%) cases of Staphylococcus aureus VO had a preceding bacteraemia with the same pathogen in the previous year. Conclusions: Staphylococcus aureus is an important pathogen causing bacteraemia with the ability to cause metastatic complications including VO. The high proportion of cases developing VO following a documented bacteraemia, sometimes many months previously, reinforce the importance of adequate aggressive treatment for bacteraemia. VO must be considered in all patients presenting with back pain up to a year after bacteraemia. Previous bacteraemias with relevant pathogens can help guide antibiotic treatment at presentation of VO and if biopsy cannot be obtained.