[Rapid diagnostic system of bacterial infection]

Approach to develop genetic detection system for bacterial infection in blood is a demanding subject because number of bacteria in blood stream is very few and in most cases the number of bacteria is less than the detection limit of gene amplification methods. At the first stage of blood sampling, we only applied gene amplification method against fastidious organisms to culture and organisms causes severe infection. Organisms which are usually found very few in blood are subjected to blood culture. After monitoring system of blood culture gave positive signal of bacterial growth, DNA or RNA in culture media were extracted and amplified with universal primers for bacteria and fungi. Amplicons were applied to a rapid sequencer. However, in case of mixed infection, the sequencing is not successful. In such cases, the amplicons are analized with DNA microarray, immobilized 16S rDNA and 28S rDNA of 1,000 human pathogenic bacteria and fungi.