Knee
Deep infection following joint replacement is a devastating complication. The misery for the patient and surgeon extends through further surgery, antibiotic chemotherapy, and a result inferior to that had the infection not occurred.1
The nature of the causative agents in deep joint infection after total knee arthroplasty is changing. Staphylococcus aureus used to be the principle organism causing deep infections in both total knee arthroplasty (TKA) and total hip arthroplasty (THA).2 Coagulase negative staphylococcus (CNS) is emerging as the leading culprit in early, delayed and late TKA deep infection.3 This is different to the leading cause of infection following THA, which remains Staphylococcus aureus. The reasons for this difference are unclear. However, having a ‘standard’ arthroplasty prophylactic antibiotic may leave TKA patients vulnerable to CNS. CNS strains are evolving with variable resistance to commonly used prophylactic antibiotic agents4 given parenterally or in cement.
In addition to ward and theatre procedures in infection prevention, local data of infection-causing organisms may be key to choosing effective prophylactic antibiotics. These are subject to change over time.5 Coffee with a friendly microbiologist once in a while may be time well spent.
Ms Leela C Biant, Consultant Orthopaedic Surgeon, Edinburgh Royal Infirmary, UK
References
1. Blom AW, Brown J, Taylor AH, Pattison G, Whitehouse S, Bannister GC. Infection after total knee arthroplasty. J Bone Joint Surg [Br] 2004;86-B:688-91.
2. Peersman G, Laskin R, Davis J, Peterson M. Infection in total knee replacement: a retrospective review of 6489 total knee replacements. Clin Orthop Relat Res 2001;392:15-23.
3. Phillips SA Biant LC Breusch SJ Dave J. Deep Prosthetic Joint Infection. The Increasing Incidence of Coagulase Negative Staphlococcus Infections. AAOS February 2012.
