Prosthetic joint infection (PJI) is one of the most devastating complications following total joint arthroplasty (TJA) of the hip and knee. Standard of care (SOC) treatment includes surgery and antimicrobials. Morbidity and mortality remain high despite contemporary treatments. The human body is colonized by billions of organisms, collectively, the microbiome, which is central to healthy immune function. Microbiome disruption, dysbiosis, can impair the immune response to infection.

Despite recent evidence that suggests dysbiosis may be implicated in PJI, the role of probiotics in the treatment of PJI is unknown. Perioperative probiotics have been demonstrated to be safe and effective for infection prevention in abdominal surgery. The investigators hypothesize that perioperative probiotics will reduce re-infection in patients treated for PJI. A multi-centered, randomized controlled trial (RCT) at two academic, tertiary care centers will be conducted to determine the impact of probiotics on recurrent infection following treatment for PJI. Controls will receive SOC; study patients will receive a probiotic, started shortly after the initiation of and for the duration of their antibiotic therapy + 7 days, in addition to SOC. Primary outcome is re-operation for recurrent infection within 1 year.

The primary and secondary aims for this RCT are:

Primary Aim 1.1 To determine the impact of administration of probiotics administered for 6 weeks after the index surgical treatment for PJI on reinfection rates (deep infection) within 1 year following revision TJA for PJI in each of the treatment arms (probiotics and standard of care).

Secondary Aims 2.1 To evaluate the incidence of superficial infections including wound drainage, cellulitis, or infections superficial to the deep fascia within 1 year following revision TJA for PJI in each of the treatment arms (probiotics and standard of care).

2.2 To evaluate the safety of use of probiotics in this population and to monitor the incidence of adverse events in patients administered probiotics versus standard of care in patients undergoing treatment for PJI.

2.3 To evaluate the 1-year mortality rate in patients undergoing revision TJA for PJI in each of treatment arms (probiotics and standard of care).

2.4 To evaluate the rate of wound healing and dehiscence in patients undergoing revision TJA for PJI in each of treatment arms (probiotics and standard of care).

2.5 To evaluate the need for chronic antibiotic suppression for the treatment of PJI at final follow-up of one year following revision TJA for PJI in each of the treatment arms (probiotics and standard of care).

2.6 To evaluate the rate of infection with Clostridium difficile within 90 days of finishing antibiotic therapy in each of the treatment arms (probiotics and standard of care). The risk of developing C. difficile infection is present for 90 days following cessation of antibiotic treatment.

All patients scheduled to undergo revision total knee arthroplasty (TKA) or total hip arthroplasty (THA) for infection at the participating institutions will be screened for eligibility in this prospective trial.

Inclusion Criteria:

• Diagnosis of PJI based upon Musculoskeletal Infection Society (MSIS) criteria
• Planned treatment with surgical debridement, antibiotics, implant retention (DAIR), single- and two-stage revision TJA for PJI with an anticipated plan for eventual discontinuation of oral/IV antibiotics.
• Patients with prior PJI in the same joint that has recurred.
• Patients who understand the benefits and risks associated with taking a probiotic and are willing and able to provide informed consent.

Exclusion Criteria:

• Fungal PJI.
• Inflammatory bowel disease, diverticulitis, history of intestinal surgery, or gastrointestinal
• issue where there is concern for gut integrity.
• History of pancreatitis at any point in time.
• History of intolerance to probiotics.
• Immunocompromised patients.
• Revision TJA for aseptic reasons