Identification Of Candida Species From Blood Cultures With Fluorescent In Situ Hybridization (fish), Polymerase Chain Reaction-restriction Fragment Length Polymorphism (pcr-rflp) And Conventional Methods

Abstract

Objectives: Rapid and accurate identification of Candida species from blood cultures is crucial to ensure effective antifungal therapy and to reduce the morbidity and mortality associated with bloodstream fungal infections. In this study, we aimed to identify Candida spp. from blood culture samples with fluorescent in situ hybridization (FISH), polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and conventional methods. Materials and Methods:A total of 50 yeast positive samples out of 325 blood culture positive samples and 50 blood culture negative samples were examined by FISH, PCR-RFLP and conventional methods to identify Candida spp.Results: All three methods generally were compatible for identification of single-species Candida spp. (p<0.001). But, FISH and PCR-RFLP for the identification of multi-species Candida spp. were found more compatible than conventional methods (p<0.001). Besides, FISH is cheaper and quicker than the other two methods in the identification of Candida spp. from blood culture positive samples. The rates of multi-species candidemia with FISH, PCR-RFLP and conventional methods were 20%, 6% and 4%, respectively. Conclusion:Both PCR-RFLP and FISH methods might be preferred for the rapid identification of Candida spp. from blood culture positive samples. However, FISH is a more suitable method for the detection of multi-species candidemia.

Hyperspectral fluorescence microscopy detects autofluorescent factors that can be exploited as a diagnostic method for Candida species differentiation

“…Other molecular methods, such as fluorescent in situ hybridization (FISH), have been described both as quick and accurate. 24 However, utilizing FISH requires that each species needing identification has its own unique probe as well as preparing the sample in such a way that the probe can enter the cell and a culture step to generate enough sample to work with. Because our method does not require large numbers of cells and is a label-free method, it may be usable on a minimally processed clinical specimen, perhaps even as a point of care diagnostic.…”

Advances inCandidadetection platforms for clinical and point-of-care applications

“…For example, in one specimen, FISH method detected C. parapsilosis , whereas the conventional method misidentified it as C. glabrata . [63,64] It was later confirmed with repeated culture methods that detected Candida spp . was C. parapsilosis as correctly identified by FISH method.…”

“…The specificity and sensitivity of PNA FISH Flow probes for Candida identification were 100% (49 of 49) and 100% (101 of 101) respectively and the whole staining process completed in 1 h.[61] Gherna et al also used the PNA FISH detection kit from AdvanDX and identified C. albicans and C. glabrata from 40 positive blood culture bottles in 1.25 h.[62] In another report, FISH oligonucleotide probes, labeled with fluorescein isothiocyanate (FITC; green signal) and fluorochrome CY3 (red signal), were synthesized by Microsynth (Switzerland, Table 2). [63,64] Candida was detected in 98% of positive blood samples (49 of 50) with PF2 all yeast probe. Different Candida spp .…”

“…was C. parapsilosis as correctly identified by FISH method. [63,64] Overall, FISH detection methods offer a rapid platform for specific identification of Candida spp. from blood culture.…”