Abstract
Aim
Data on Prosthetic joint infection (PJI) caused by multi-drug resistant (MDR) or XDR (extensively drug resistant) Gram negative bacteria (GNB) are limited. Treatment options are also restricted. We conducted a multi-national, multi-center assessment of clinical data and factors of outcome for these infections.
Method
PJI were defined upon international guidelines. Data from 2000–2015 on demographics, clinical features, microbiology, surgical treatment and antimicrobial therapy was collected retrospectively. Factors associated with treatment success were evaluated by logistic regression analysis.
Results
A total of 133 PJI were evaluated. Female (n=84, 61.4%) and the elderly [mean age (+/-SD) 73 (12.7)] predominated. Diabetes mellitus was the most frequent comorbidity (n=42,32.1%) followed by rheumatoid arthritis (n=14,10.7). Most PJI were early infections (84.4 %). XDR accounted for 23 cases; half of them due to Pseudomonas aeruginosa. Prevalence of MDR or XDR GNB was not different between early and late PJIs (p=0.114). Overall, P.aeruginosa (n=25, 19.1%) was followed by Klebsiella spp (n=23,17.6%) and Enterobacter spp (n=22,16.8%). PJI was located at the hip (n=85 65.6%), knee (n=41,31.3%), shoulder (n=3,2.3%) and ankle (n=1, 0.8%). Clinical characteristics included soft tissue infection (66.4%), pain (51.1%), fever (32.1%) and sinus tract(29.8%). Surgery for PJIs consisted of DAIR (debridement, antibiotics and implant retention), (n=64, 49.6%), followed by explantation of the arthroplasty (n=32, 24.8%), two-stage revision (n=16, 12,4%), one stage revision (n=9, 7%), arthrodesis (n=2, 1.6%). Median duration of antibiotic therapy was 51 days (IQR 25–75: 40–90 days). Cure after treatment was assessed in 78 patients (58.6%). No-DAIR surgical procedures in PJIs were more likely to be successful compared to DAIR surgery (75.8% vs 50%, OR 3.13, 95% CI:1.47–6.70, p=0.003)both in early or late infections.
Conclusions
PJI by MDR/XDR GNB affects female, the elderly with comorbidities and previous surgery for PJI. P.aeruginosa is frequent, mostly XRD. No-DAIR procedures have higher probability of treatment success than DAIR even in early infection. Despite surgery and long-term antimicrobial administration, treatment success was less than 60%, probably reflecting the lack of effective treatment options.
