Comparative study of the techniques used for the diagnosis of bacteremia in catheter-related infections

Catheter-related infections represent a significant source of morbidity, mortality and prolongation of hospital stay. Bacteriological diagnosis can be approached using various methodologies. This study aimed at evaluating the sensitivity and specificity of the techniques commonly used in the microbiology laboratory. One hundred and eighty catheters were analysed using the Maki, sonication (Sherertz technique) and vortex (Brun-Buisson technique) techniques. Each technique was applied first, second and third, in a systematic order. The sensitivity and specificity of the Maki method were 67% and 75% respectively, while for the Brun-Buisson and Sherertz quantitative techniques they were 78% and 83%, and 56% and 88% respectively. It was observed that the Brun-Buisson technique performed best when applied first, the Sherertz technique second, and the Maki technique third.