Perioperative antibiotics should not be withheld in proven cases of periprosthetic infection

Area of Science:

• Orthopedic surgery
• Infectious disease diagnostics
• Microbiology

Background:

• Periprosthetic infection diagnosis relies on intraoperative cultures, but organism isolation is not always successful.
• Preoperative antibiotics may potentially interfere with the accuracy of intraoperative cultures.

Purpose of the Study:

• To determine if preoperative antibiotics affect the isolation of organisms from intraoperative tissue samples in patients undergoing total knee arthroplasty (TKA).
• To investigate the concordance between preoperative joint aspirate cultures and intraoperative cultures.

Main Methods:

• Retrospective review of 171 patients with periprosthetic infections (2000-2005) who had positive preoperative aspiration cultures.
• Documentation of preoperative antibiotic administration and analysis of intraoperative culture results.
• Comparison of false-negative rates between patients who received preoperative antibiotics and those who did not.

Main Results:

• The false-negative rate for intraoperative cultures was 12.5% in patients who received preoperative antibiotics versus 8% in those who did not, with no statistically significant difference observed.
• Organisms isolated from preoperative aspirate cultures were identical to intraoperative isolates in 97% of cases.

Conclusions:

• Administration of preoperative antibiotics to patients with positive preoperative joint aspirates does not significantly increase the rate of false-negative intraoperative cultures.
• Preoperative joint aspiration cultures are reliable indicators of the causative organisms in periprosthetic joint infections, even when patients receive preoperative antibiotics.