2019 J. Leonard Goldner Award Winner: A Novel Intraoperative Technique Seeding Morselized Bone Tissue into Pediatric Blood Culture Bottles Improves Microbiological Diagnosis in Patients with Foot and Ankle Osteomyelitis

CATEGORY: Basic Sciences/Biologics, Diabetes INTRODUCTION/PURPOSE: Bone infection in the foot is a challenging pathology that frequently leads to amputation and major disability. Agent identification and antimicrobial susceptibility-guided therapy is the key for a successful treatment. Standard culture methods for bone tissue have demonstrated poor sensitivity. It has been reported that synovial fluid culture sensitivity is enhanced when seeded into pediatric blood culture bottles (PBCB), however, its performance for bone infection has yet to be determined. The aim of this study was to evaluate a novel method to obtain and process infected bone tissue using PBCB and comparing it with the standard technique. METHODS: Patients admitted at a single university hospital with foot osteomyelitis between 2008 and 2017 were recruited prospectively. The diagnosis was made by clinical, laboratory and imaging findings. A representative sample of infected bone tissue was obtained for each patient and simultaneously processed using the standard technique for solid tissue cultures (SCM) and a morselized bone sample that was seeded into a PBCB (BacT/ALERT® PF). Culture sensitivity and number of agents detected for each technique were compared using the McNemar and the Mann Whitney tests respectively. RESULTS: Over the period studied, 107 patients fitted the inclusion criteria. Of these, 63 patients had a diabetic-related infection. The causative agent was identified in 60.7% using the SCM and in 97.2% using PBCB (p < 0.001). We detected a mean of 1.05 bacteria species using SCM and 1.67 using PBCB (p<0.01). PBCB retrieved 1 bacterial species in 50.5% of the samples and 2 or more bacterial species in 46.7%. The SCM detected 1 bacterial species in 29% of the samples and 2 or more bacterial species in 31.7%. CONCLUSION: In this cohort, culture technique using morselized bone tissue seeded in PBCB identified the causative agent in a significantly larger percentage than SCM. Additionally, this method identified a larger number of agents. These findings demonstrate that this novel, simple and reproducible technique for culturing bone tissue samples allows a better microbiological diagnosis, without additional intraoperative risks, compared with standard methods.