Oral tetracyclines for bone and joint infections: what do we know?

Background and aim: Complex bone and joint infections (BJIs), including prosthetic joint infections (PJIs) and infections associated with osteosynthetic materials, present significant treatment challenges that often require surgical intervention and prolonged antibiotic therapy. In France, the incidence of PJIs in knee and hip arthroplasties ranges from 0.79 % to 2.4 %, with staphylococci being the primary pathogens involved. Recent studies have suggested that oral antibiotic therapy may be as effective as intravenous therapy and that 12 weeks of antibiotic treatment are needed. Tetracyclines, particularly doxycycline and minocycline, are of interest because of their broad-spectrum activities, good oral bioavailability, and potential efficacy in treating BJIs. We aimed to provide a literature review on the role of oral tetracyclines in the management of BJIs. Method: We performed a systematic review of the literature identified via an electronic search of PubMed and ScienceDirect. Results: A total of 648 articles were screened, and 31 studies were included. Pharmacological studies demonstrated that the bone to blood penetration ratio ranged from 0.06 to 0.75. Less than 20 % of strains implicated in BJIs exhibited resistance to oral tetracyclines. Four studies demonstrated potential inhibition of strain growth. Eight studies that included 62 patients reported curative treatment, with a success rate ranging from 82 % to 100 % for PJIs regardless of the surgical management. For suppressive therapy, 10 studies that included 201 patients reported success rates ranging from 57 % to 100 %. The rate of adverse effects ranged from 0 % to 14 % for curative treatment and from 0 % to 57 % for suppressive treatment, leading to treatment discontinuation in less than 20 % of cases. Conclusion: This review highlights that the number of studies supporting the use of oral tetracyclines for the treatment of BJIs is limited. More robust pharmacological and clinical studies are needed to confirm the safety and efficacy profiles of oral tetracyclines for the treatment of BJIs.