Outpatient parenteral antibiotic therapy (OPAT) for bone and joint infections: experience from a UK teaching...

We describe failure rates of 198 patients with bone and joint infection (BJI), including prosthetic joint infection and diabetic foot osteomyelitis, managed through the Glasgow centre for outpatient parenteral antibiotic therapy (OPAT) over a period of 4 years. Outcomes following initial intravenous antimicrobial therapy and a median follow-up time of 60 weeks are described.

A prospectively maintained registry of all patients attending OPAT was examined for cases of BJI. Once identified, patient case records were reviewed and data extracted. Diagnosis, demographics, microbiology and treatment were recorded, and case records were examined for evidence of failing initial prescribed OPAT therapy and up to 24 months of follow-up.

One hundred and ninety-eight cases of BJI were identified. The overall success rate following initial OPAT was 86.4%, with a range from 71.8% success rate for diabetic foot or stump infection (DFI) to 100% for metalwork-related infection. The failure rate over the follow-up period was 29.8%. Factors associated with poor initial outcome included older age, methicillin-resistant Staphylococcus aureus infection and DFI, factors that continued to explain failure up to 24 months in multivariate survival analysis.

For the majority of conditions, BJI can be successfully managed through OPAT. Identification of those likely to respond less well, including older patients, those with DFI and those with infections by resistant organisms, may encourage enhanced vigilance and consideration of newer or more aggressive treatments in these subgroups of patients.