Effect of 8-week prebiotic supplementation on gut health in Prosthetic Joint Infection patients

This is a randomized double blind placebo controlled study. The participants will be recruited when they present to the Department of Orthopaedics for the treatment of Prosthetic Joint Infection (PJI). Patients who are planned to undergo two stage revision for the treatment of PJI will be approached face to face to discuss participation in the study by the treating surgeons. Potential participants may have family members or others present to discuss the process. The consent process will primarily be done by the registrar on-call when patients are seen and admitted to the hospital or when patients are seen in the outpatient clinic by the Orthopaedic doctors. Each enrolled participant will be assigned a code and randomised to the placebo group or the control group using a computer-generated block randomisation plan by one of the study investigator. Treating surgeon will be blinded to the randomization plan. Once enrolled, all patients will undergo standard-of-care treatment for their PJI which includes optimization by a multidisciplinary team comprising of anaesthetist, infectious diseases consultant, orthopaedic doctors and joint replacement nurses as required. All patients will be given the required antibiotic therapy. This is independent of participant consent. After the first stage of revision surgery, the recruited patients are randomized to intervention group that will be adminstered one sachet of a prebiotic fiber supplement (64g) either mixed with milk or juice or food of their choice before or with the meals once a day for 8-weeks. All in-patients will be given the product with breakfast, supervised by the study dietician. On discharge, the patients will be given the clinical supplies to complete the supplementation period of daily for 8 weeks with a copy of printed instructions. All patients will be asked to bring the empty sachets to their follow-up appointments to record compliance. One of the investigators will ensure compliance through regular phone calls. Supplementation will start soon after the first stage revision when the patient is well enough to take oral foods. Some patients are sick and need longer ICU stay, hence the start of supplementation will vary from case to case. The supplementation phase will be for 8-weeks. The first stage revision surgery comprises of inserting a temporary antibiotic coated spacer for treatment of local infection. After the first stage revision, patients will be monitored for infection resolution through physical and blood examinations. Once the blood tests confirm infection resolution, which may vary from 12-24 weeks postop, patients will undergo second stage revision surgery which is the definitive replacement surgery and involves inserting a permanent prosthesis.