Suppressive Antibiotic Therapy After Debridement, Antibiotics, and Implant Retention is Well-Tolerated Without Inducing Resistance: A Multicenter Study.

BACKGROUND: Suppressive antibiotic therapy (SAT) after total joint arthroplasty (TJA) debridement, antibiotics, and implant retention (DAIR) maximizes reoperation-free survival. We evaluated SAT after DAIR of acutely infected primary TJA regarding: 1) adverse drug reaction (ADR)/intolerance; 2) reoperation for infection; and 3) antibiotic resistance. METHODS: Patients who underwent total knee arthroplasty (TKA) or total hip arthroplasty (THA) DAIR for acute periprosthetic joint infection at two academic medical centers from 2015 to 2020 were identified (n = 115). Data were collected on patient demographics, infecting organisms, antibiotics, ADR/intolerances, reoperations, and antibiotic resistances. Median SAT duration was 11 months. Stepwise multivariate logistic regressions were used to identify covariates significantly associated with outcomes of interest. RESULTS: There were 11.1 and 16.3% of TKA and THA DAIR patients, respectively, who had ADR/intolerance to SAT. Patients prescribed trimethoprim/sulfamethoxazole (P = .0014) or combination antibiotic therapy (P = .0169) after TKA DAIR had increased risk of ADR/intolerance. There was no difference in reoperation-free survival between TKA (83.3%) and THA (65.1%) DAIR (P = .5900) at mean 2.8-year follow-up. Risk of reoperation for infection was higher among TKA Staphylococcus aureus infections (P = .0004) and lower with increased SAT duration (P < .0450). The optimal duration of SAT was nearly 2 years. No cases of antibiotic resistance developed due to SAT. CONCLUSIONS: Consider SAT after TJA DAIR due to improved reoperation-free survival and favorable safety profile. Prolonged SAT did not induce antibiotic resistance. Use trimethoprim/sulfamethoxazole with caution because of the increased likelihood of ADR/intolerance. LEVEL OF EVIDENCE: Therapeutic Level III.

How Many Patients Qualify for Extended Oral Antibiotic Prophylaxis Infection Following Primary and Revision Hip and Knee Arthroplasties?

Extended oral antibiotic prophylaxis (EOAP) has been suggested to reduce rates of periprosthetic joint infection (PJI) postoperatively after total joint arthroplasty (TJA). The purpose of this multicenter study is to define how many TJA patients are considered high risk for developing PJI based on published EOAP criteria and determine whether this status is associated with socioeconomic or demographic factors. All primary and aseptic revision TJAs performed in 2019 at three academic medical centers were reviewed. High-risk status was defined based on prior published EOAP criteria. Area deprivation index (ADI) was calculated as a measure of socioeconomic status. Data were reported as means with standard deviation. Both overall and institutional differences were compared. Of the 2,511 patients (2,042 primary and 469 revision) in this cohort, 73.3% met criteria for high risk (primary: 72.9% [1,490] and revision: 74.6% [350]). Patient's race or age did not have a significant impact on risk designation; however, a larger proportion of high-risk patients were women (p = 0.002) and had higher Elixhauser scores (p < 0.001). The mean ADI for high-risk patients was higher (more disadvantaged) than for standard-risk patients (64.0 [20.8] vs. 59.4 [59.4]) (p < 0.001). Over 72% of primary and revision TJA patients at three medical centers met published criteria for EOAP. These patients were more often women, had more comorbidities, and lived in more disadvantaged areas. Our findings suggest that most patients qualify for EOAP, which may call for more stringent criteria on who would benefit extended antibiotic prophylaxis.