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. CONCLUSION: 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.

Value of CT-guided biopsy in the diagnosis of septic discitis.

AIM: To determine the role of CT-guided biopsy in the management of cases of infective discitis. METHODS: Data were examined from a retrospective case series of CT-guided biopsies for the 5-year period ending June 2006. RESULTS: 98 CT-guided biopsies were performed in the study period on 103 patients. Malignancy was diagnosed in 49 episodes. Discitis and paravertebral abscess accounted for 27 cases. Culture was positive in nine of 25 (36%) samples received by the microbiology laboratory. Staphylococcus aureus (four cases) and Mycobacterium tuberculosis (three cases) were the most frequent organisms isolated, followed by group G streptococci and coagulase-negative staphylococci (one case each). Blood cultures were diagnostic in a further nine patients. The main reason for a negative culture was prior antimicrobial therapy. The biopsy changed management in 9/25 (36%) of cases. There were no reported adverse events. CONCLUSION: Septic discitis is a serious condition with a wide variety of infective causes. CT-guided biopsy is a useful tool when the diagnosis of infectious spinal infection is considered in terms of commencing and targeting therapy, and it is a safe and well-tolerated procedure.