[Bacterial pathogens of periprosthetic infections and diagnostic possibilities]

Successful treatment of patients with periprosthetic infection (PPI) requires a correct diagnosis supported by clinical, imaging, microbiological and other laboratory evidence. Equally important is to determine the causative agent of the infection as this may affect the subsequent treatment strategy. The paper aims at presenting cultivation results in a group of PPI patients and their comparison with molecular biology methods.

Material obtained during operations of PPI patients was examined by both the standard culture methods and the PCR technique to identify the etiological agents. The results were statistically compared.

In total, the group comprised 49 patients with hip, knee or elbow replacement infection verified during the operation. In 42 cases (85.7 %), the infectious agent was identified by cultivation. The infection was most frequently (62.0 %) caused by coagulase-negative staphylococci and Staphylococcus aureus. Monomicrobial and polymicrobial infections were demonstrated in 35 (71.4 %) and 7 (14.3 %) patients, respectively. The PCR assay aimed at the 16S rRNA segment of bacterial DNA was performed in 35 patients, with positive results in 25 cases (71.4 %). In 82.6 %, the agents detected by specific PCR were consistent with the cultivation results. A statistically non-significant difference in sensitivity between the two methods was found, with higher specificity in the case of PCR.

Standard cultivation methods remain a highly successful and useful tool for identifying the PPI causative agents.