Differing Microorganism Profile in Early and Late Prosthetic Joint Infections Following Primary Total Knee Arthroplasty — Implications for Empiric Antibiotic Treatment

Prosthetic joint infection (PJI) is the leading cause of revision following total knee arthroplasty (TKA). Prior to microorganism identification, the choice of the correct empiric antibiotics is critical to treatment success. This study aims to 1) compare the microorganism and resistance profile in early and late PJIs; 2) recommend appropriate empiric antibiotics. A multicentre retrospective review was performed over a 15-year period. First episode PJIs were classified by both the Tsukayama Classification and Auckland Classification. For each PJI case, the causative organism and antibiotic sensitivity were recorded. Of eligible patients, 232 culture-positive PJI cases were included. Using either classification system, early PJIs (