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FTIR spectroscopy in medical mycology: Applications to the differentiation and typing of Candida

Laboratoire de Parasitologie-Mycologie, CHU de Reims, EA 3800, IFR53, Université de Reims Champagne-Ardenne, 51 rue Cognacq-Jay, 51096 Reims Cedex, France.
Analytical and Bioanalytical Chemistry (Impact Factor: 3.58). 04/2007; 387(5):1729-37. DOI: 10.1007/s00216-006-1005-1
Source: PubMed

ABSTRACT The incidence of fungal infections, in particular candidiasis and aspergillosis, has considerably increased during the last three decades. This is mainly due to advances in medical treatments and technologies. In high risk patients (e.g. in haematology or intensive care), the prognosis of invasive candidiasis is relatively poor. Therefore, a rapid and correct identification of the infectious agent is important for an efficient and prompt therapy. Most clinical laboratories rely on conventional identification methods that are based on morphological, physiological and nutritional characteristics. However, these have their limitations because they are time-consuming and not always very accurate. Moreover, molecular methods may be required to determine the genetic relationship between the infectious strains, for instance in Candida outbreaks. In addition, the latter methods require time, expensive consumables and highly trained staff to be performed adequately. In this study, we have applied the FTIR spectroscopic approach to different situations encountered in routine mycological diagnosis. We show the potentials of this phenotypic approach, used in parallel with routine identification methods, for the differentiation of 3 frequently encountered Candida species (C. albicans, C. glabrata and C. krusei) by using both suspensions and microcolonies. This approach, developed for an early discrimination, may help in the initial choice of antifungal treatment. Furthermore, we demonstrate the feasibility of the method for intraspecies comparison (typing) of 3 Candida species (C. albicans, C. glabrata and C. parapsilosis), particularly when an outbreak is suspected.

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    • "Despite the fact that conventional/classical tests are largely applied, yet, these tests are faced with several constrains. Time consuming and low discriminative power between closely related species are the major constrains [16]. Currently, genotypic methods are practically preferred than phenotypic methods. "
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    06/2013; 1(1):15–20. DOI:10.1016/j.ijvsm.2013.03.001
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    • "Eng., 28(4), 398-409, Dec. 2012 404 diferenciar os três espectros. Esse resultado demonstra que, mesmo nos casos em que os espectros de diferentes micro-organismos apresentem o mesmo aspecto visual, a análise estatística multivariada pode ser potencialmente útil para diferenciar os espectros desses micro-organismos (Essendoubi et al., 2005; Naumann, 2000; Timmins et al., 1998; Tintelnot et al., 2000; Toubas et al., 2007). "
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    12/2012; 28(4):398-409. DOI:10.4322/rbeb.2012.037
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    • "Fungi, which include filamentous fungi and yeasts, are very important organisms. They are employed in the production of pharmaceuticals, enzymes, organic acids and food, and some of them are associated with several diseases affecting humans and other animals [1] [5] [24] [37] [38] [43] [45] [47]. The earliest system for fungal species classification relied on morphological characters, mainly those of reproductive structures. "
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