Rifampicin resistance and risk factors associated with significantly lower recovery rates after two-stage revision in patients with prosthetic joint infection.

Objectives: Rifampicin plays a key role in the management of prosthetic joint infections (PJIs); however, the emergence of rifampicin resistance is associated with less favourable clinical outcomes. The purpose of this study was to investigate the impact of rifampicin resistance and other patient-related factors on recovery rates among patients with PJI undergoing two-stage revision.

Methods: We reviewed medical records and microbiology reports of 73 patients (41 males and 32 females) undergoing two-stage revision due to PJI between 2017 and 2019. Patient-specific data, comorbidities and the antibiotic resistance of microbiological isolates were registered. Forty-eight patients had hip, 22 had knee, 2 had shoulder and 1 had elbow joint infection. Obtained data were statistically analysed with a logistic regression model.

Results: Rifampicin-sensitive organism was isolated in 53 cases (72.6%). Recovery rate was 92.5% in the sensitive and 60.0% in the resistant group. We observed that rifampicin resistance significantly reduced the probability of recovery. Furthermore, in the rifampicin-sensitive group, the probability of recovery decreased with advancing age with a significant drop above the age of 60 years. The effect of age is negligible in the rifampicin-resistant group. We also found that type 2 diabetes mellitus has a negative effect on recovery. Coagulase-negative Staphylococci were predominant in the rifampicin-sensitive (50% of the isolates) and Gram-negative rods in the resistant group (40%).

Conclusions: Rifampicin resistance was associated with lower recovery rates among patients undergoing two-stage revision due to PJI. Higher age and type 2 diabetes mellitus had negative impact on clinical outcome.