We define an algorithm to optimize bone and joint infection diagnosis in adults on synovial fluid samples. This prospective multi-center study included a large number of synovial fluids and compared the performance of classical culture on different media, inoculation of synovial fluid in blood culture bottles, and broad-range and specific PCR. We proposed an algorithm associating culture onto three solid media and into blood culture bottles and 16S, Staphylococcus, and Streptococcus PCR.

Costs related to off-label expensive antibiotics used to treat bone and joint infections (BJIs) in a referral centre in France were analysed in this cohort study. Despite the large increase in the number of patients treated with these antibiotics, the overall costs remained stable (approximately EUR 1 million) and were helped by the appearance of generic molecules at lower prices. Production of generic antibiotics at low cost is essential to limit the financial burden of the management of BJIs.