Identification of Candida albicans from clinical specimens obtained from Lebanese hospitals by fluorescence resonance energy transfer and probe melting curves. (c2005)

Abstract

The fungi are an independent group as plants and animals. Some fungi including the yeast are pathogenic to mammals and particularly humans. The increasing frequency of invasive fungal infections and the high mortality associated with disseminated fungal diseases have underscored the importance of rapid detection of these pathogenic fungi - most common of which are the Candida Spp. Thus, prompt detection and accurate speciation may help to improve fungal disease management as a whole and lead to more rational use of anti-fungal. Traditional identification methods are often time-consuming and depend largely on the skill and experience of the technician. In light of the above, the aim of the experiment was to evaluate a more recent realtime PCR technique that has been developed for the identification of many microbial organisms including the Candida spp and comparing that to results obtained from Lebanese hospitals. This technique relies on Fluorescence Resonance Energy Transfer and Probe Melting Curves. The above was done by using a Lightcycler Candida Kit from Roche Applied Science. The technique was used on 100 samples presumed to be C. albicans gathered from the Lebanese hospitals and its results were compared to those given by the hospital and to the results of a germ tube test repeated at LAU. 24 samples out of the 100 appeared negative on the light cycler. This discrepancy was quite significant with a p< 0.001. Further more, 6 samples gave false positive results with germ tube test and 17 showed a false negative result. Both, these results are significant with respect to the rate of false positivity and negativity. The real-time PCR is rapid, simple and specific and offers many advantages in reference to the conventional methods. Many discrepancies occurred in the result between the hospital and the repetition of the germ tube itself. Thus, in light of the results hospitals are advised to reconsider their techniques of identification.