Title : Early prosthetic joint infection of the knee due to clostridiodes difficile following episode of colitis
Abstract:
Introduction: Extraintestinal manifestations of Clostridioides difficile infection (CDI) are rare, occurring in <1% of reported CDI cases. Risk factors include intestinal barrier disruption, previous hospitalization, advanced age (>65 years), and use of broad-spectrum antibiotics. One extraintestinal manifestation of CDI is septic arthritis, including prosthetic joint infection (PJI). Previously reported PJI due to C. difficile often involved the hip and occurred months after initial CDI episode. We present a case of C. difficile PJI arising shortly after severe colitis following TKA, highlighting an unusually early and aggressive presentation.
Case Presentation: An 85-year-old female with a past medical history of hypothyroidism, hypertension, and osteoporosis, underwent a right TKA. Nine days later, she required revision due to a medial femoral condyle periprosthetic fracture. Her postoperative course was complicated by profuse and watery diarrhea associated with cramping abdominal pain and intermittent nausea. She tested positive for C. difficile by PCR and toxin EIA. She then completed a ten-day course of fidaxomicin and vancomycin, and she was discharged to an acute rehabilitation facility.
Three weeks later she presented with acute right knee pain associated with swelling and brown discharge as well as fever and chills. X-ray showed stable post-operative changes. CT of her right femur revealed 2 rim-enhancing collections, one within the rectus femoris muscle and another at the superficial aspect of the lateral fixation plate. Arthrocentesis revealed purulent fluid with 33207 total nucleated cells and 92% segmented neutrophils. She was started on vancomycin and cefepime for suspected PJI. Orthopedics performed incision and drainage (I&D), polyethylene liner exchange, and placement of antibiotic beads. Six days after initial I&D, C. difficile was isolated from intra-operative anaerobic tissue culture. Cefepime was stopped and metronidazole was added to her antimicrobial regimen. She then underwent repeat I&D with removal of all hardware and placement of an antibiotic spacer. Intraoperative culture again grew C. difficile. She received IV vancomycin for 7 days after recent I&D and continued oral metronidazole for a planned six-week course.
Discussion: PJI caused by C. difficile is exceptionally rare. The proposed mechanism for pathogenesis of prosthetic joint septic arthritis is hematogenous spread of translocated gut bacteria or direct inoculation during surgery. Additionally, surgical sites can be inoculated with spores from hospital surfaces. Isolation of the offending agent is typically achieved through anaerobic culture of intra-operative tissue. Blood cultures remain negative as in this case. Inpatient treatment for cases of septic arthritis caused by C. difficle are repeated debridement, vancomycin and metronidazole. Outpatient treatment from prior cases typically require prolonged antibiotic suppression of infection following acute surgical management, but show favorable results with adequate infection prevention and relapse, even after one-year follow-up. Previous cases for antibiotic courses upon discharge include either metronidazole or doxycycline. Patients with prolonged metronidazole use should be monitored for the development of peripheral neuropathy.
