Periprosthetic joint infections are a rare but serious complication following primary and revision arthroplasty. Rapid and reliable diagnosis is required for appropriate treatment. We have developed and validated a specific mPCR for the detection of the most common pathogens of prosthetic joint infections, which was evaluated in a prospective study (341 samples) in comparison to cultivation, broad-spectrum PCR and metagenomic analysis. The molecular methods proved to be particularly useful for the detection of pathogens in culture-negative samples and in patients who had previously received antibiotic therapy. The mPCR had low sensitivity in detecting chronic low-grade infections, while broad-spectrum PCR had the highest sensitivity compared to culture. mPCR had the highest specificity. Sensitivity and specificity were further increased when we combined cultivation and molecular methods. In this dissertation, we also performed a genome analysis (typing and detection of 40 selected virulence factors) of 64 Cutibacterium isolates (C. acnes, C. avidum, C. granulsoum in C. namnetense). No correlation was found between the selected virulence factors and the different sequence types of C. acnes, the anatomical sites or the distribution among the isolates associated or not with infection. However, we observed differences in the presence of virulence factors between Cutibacterium spp. species, subspecies and phylotypes of C. acnes.
|
