Effects of different pretreatment methods on microbial recovery of infected tissues

Abstract

This study aimed to evaluate the effects of different pretreatment methods on the degree of microbial recovery in infected tissues. Standard strains of Staphylococcus aureus (SA), Escherichia coli (EC) and Candida albicans (CA) were used to construct single-surface, full-surface, and internal infection models in sterile pork tissue. Manual milling (MM), mechanical homogenization (MH), ultrasonic lysis (UL), dithiothreitol (DTT), and direct culture (DC) were used to pretreat infection tissues, the ability of the different pretreatment methods to achieve pathogen recovery in the different bacterial infection models was compared. At the same time, periprosthetic tissues collected from periprosthetic joint infection (PJI) were pretreated with the same methods. We showed that regardless of whether the single-surface or full-surface infection model was used in SA, EC, and CA infection, the microbial acquisition in the MH group was significantly higher than that in the MM (P <0.01) and UL groups (P <0.01). In the internal infection model, the microbial acquisition of the MH group was significantly higher than that of the MM (P <0.01), UL (P <0.01), DTT (P <0.01), and DC groups (P <0.01). In the PJI cases, the number of bacterial colonies obtained by MH was significantly higher than that obtained by other pretreatment methods (P = 0.004). The effects of MH and DTT in microbial recovery were significantly better than that of DC, UL and MM, and these methods can be used to process multiple tissue samples at the same time, which can further improve the efficiency of clinical microbial diagnosis.