A simple pill may supercharge antibiotics against stubborn bone infections

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age ≥ 18 years old * Effective contraception throughout the study period for women of childbearing potential. * Ongoing oral amoxicillin monotherapy for the treatment of a documented osteoarticular infection, including: osteoarticular infection without implanted material (arthritis, osteitis, osteomyelitis), osteoarticular infection involving implanted material (osteoarticular prosthesis, osteosynthesis hardware, external fixator, or arthrodesis material excluding spinal instrumentation), or spondylodiscitis with or without implanted material, defined by the following criteria: * Microbiological documentation of one or more pathogens for which amoxicillin is the recommended antibiotic treatment (Enterococcus spp. susceptible to ampicillin, Streptococcus spp., Cutibacterium spp., and other anaerobic bacteria susceptible to amoxicillin), obtained from blood cultures, disco-vertebral biopsy, bone biopsy, joint aspiration, and/or intraoperative samples. * Treatment with oral amoxicillin monotherapy for the management of this osteoarticular infection, with the diagnosis established based on the following criteria: * Clinical signs, with one or more of the following: fever, hypothermia, chills, pain, spinal pain, arthritis, inflammatory or dehiscent scar over osteoarticular hardware, fistula, purulent drainage, and/or * Suggestive radiological findings (X-ray, CT scan, or MRI): bone lysis, periosteal reaction, sequestrum, soft tissue collection, joint effusion, radiolucent line around osteoarticular hardware suggestive of loosening. In cases of spondylodiscitis: T2 hyperintensity of the disc, T1 hypointensity of adjacent vertebral endplates on MRI, posterior facet joint arthritis, and/or * Final diagnosis of osteoarticular infection established by the treating medical or multidisciplinary surgical team based on a combination of clinical, microbiological, radiological, or other relevant findings. Patients with a history of one or more previous osteoarticular infections are eligible. * Oral amoxicillin treatment permitted based on clinical and biological improvement. * Planned hospitalization duration ≥4 days after inclusion. * Patient informed and having provided written informed consent to participate. Exclusion Criteria: * Pregnancy or breastfeeding. * Severe allergy to β-lactams or documented allergic contraindication to penicillins confirmed by allergy testing. * Contraindication to probenecid, including: hypersensitivity to probenecid, an ongoing acute gout attack, nephrolithiasis, secondary hyperuricemia due to chemotherapy, radiotherapy, or myeloproliferative syndrome because of the increased risk of uric acid nephropathy, and primary hyperuricemia due to uric acid overproduction. * Ongoing treatment, which cannot be discontinued, with a medication known to interact with probenecid: methotrexate, diprophylline, cholestyramine, phenobarbital, and zidovudine. If treatment discontinuation is possible, the washout period will be left to the investigator's discretion. * Renal impairment defined by an estimated glomerular filtration rate (eGFR) \<60 mL/min/1.73 m² according to the CKD-EPI equation, based on the most recent value available during hospitalization before inclusion. * Augmented renal clearance defined by an eGFR \>130 mL/min/1.73 m² according to the CKD-EPI equation, based on the most recent value available during hospitalization before inclusion. * Body weight \<40 kg or \>110 kg. * Severe hepatic impairment defined by prothrombin time (PT) \<50%, based on the most recent value available during hospitalization before inclusion. * Patients under legal guardianship, curatorship, judicial protection, or deprived of liberty. * Patients with cognitive impairment or who, in the investigator's opinion, are unable to understand the study, participate in all study visits considering the treatments and procedures required by the protocol, and/or provide informed consent. * Patients not affiliated with a social security system or another health insurance scheme, including patients covered by State medical aid (AME). * Concomitant participation in another clinical trial involving a medicinal product for human use, a clinical investigation of a medical device, or any interventional research involving human participants. * Participation in non-interventional research is permitted