Improvement of detection of bacterial pathogens in normally sterile body sites with a focus on orthopedic samples by use of a commercial 16S rRNA broad-range PCR and sequence analysis.

A new commercially available universal 16S and 18S rRNA gene PCR test, which is followed by sequence analysis of amplicons (SepsiTest), was evaluated for rapid identification of pathogens in the diagnosis of bone and joint infections. Eighty-three orthopedic samples and 21 specimens from other normally sterile body sites collected from 84 patients were analyzed in parallel by culture and PCR for detection of bacteria and fungi. Compared to culture, the diagnostic sensitivity and specificity of PCR were 88.5% and 83.5%, respectively. The detection rate of PCR (34.6%) was higher than that of bacterial culture (25.0%) as a consequence of the presence of fastidious and noncultivable species in samples and antibiotic treatment of patients. Thirteen culture-negative infections were identified by PCR, and PCR was able to detect culture-proven polymicrobial infections. On the other hand, three samples were culture positive but PCR negative. SepsiTest was demonstrated to be a valuable supplemental tool in the rapid detection of bacteria, especially for fastidious and noncultivable organisms, allowing earlier initiation of pathogen-adapted therapy in patients with bone and joint infections.