Comparison of independent and dependent culture methods for the detection of transient bacteremia in diabetic subjects with chronic periodontitis

Introduction: Oral-derived bacteremia may occur after several dental procedures and routine daily activities. Some conditions of the oral cavity may favor episodes of bacteremia. This would be the case of patients with diabetes mellitus and periodontitis, who exhibit exacerbated gingival inflammation and may be more prone to developing oral-derived bacteremia. Objective: To compare the effectiveness of an independent culture method (quantitative real-time PCR-qCR) and the most commonly used method (BacT-ALERT 3D (R)) for the diagnosis of bacteremia. Materials and methods: Blood samples were drawn from subjects with type 2 diabetes mellitus and chronic periodontitis before and after apple chewing. Samples were processed by an automated blood culture system (BacT-ALERT 3D (R)) monitored for 15 days with suitable subculture of positive cultures. In parallel, whole DNA from blood samples was purified using a commercial kit and screened by qPCR using a universal primer set of 16S rDNA for bacteria detection. Results: Blood cultures taken before apple chewing were shown to be negative by the two diagnostic methods. After chewing, two samples (11%) showed bacterial growth by BacT-ALERT 3D (R) whereas qPCR did not detect the presence of bacteria in any sample. Conclusions: qPCR did not show greater effectiveness than the BacT-ALERT 3D (R) in the detection of bacteremia of oral origin.