Detection and identification of Candida spp. in human serum by LightCycler® real-time polymerase chain reaction

The aim of this work was to develop LightCycler® real-time polymerase chain reaction method to allow rapid detection and identification of Candida spp. in human serum with panfungal primers (internal transcribed spacer [ITS] and L18). Melting-curve analysis of the ITS sequences showed that each amplicon presented a specific melting point and enabled identification of 5 Candida spp. After parameters optimization, 58 sera were preliminary analyzed from 23 patients. For L18 primers, the LightCycler® system enabled detection of DNA in 92% of patients with positive blood culture. These primers were not able to differentiate between species of Candida. By using ITS primers, the LightCycler® system enabled detection of DNA in sera from 76.9% of patients with positive blood culture. With ITS primers, the species responsible for the infection was identified for 11 patients. These data revealed the LightCycler® as a potential tool for early detection and identification of Candida.