Species Identification of Candida Strains Isolated from Patients with Candidemia, Hospitalized in Tehran, by Enzymatic Digestion of ITS–rDNA

Document Type : Original Article (s)

Authors

1 Assistant Professor, Department of Biology, School of Applied Sciences, Imam Hossein University, Tehran, Iran

2 Associate Professor, Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran

3 Assistant Professor, Department of Microbiology, Applied Microbiology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran

4 Department of Medical Technology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran

Abstract

Background: Candidemia is a very important infection in terms of incidence and mortality. It can be caused by several species of the genus Candida and should be diagnosed and treated quickly. Although Candida albicans is still the most common causative agent of candidemia, the incidence of blood infections due to non-albicans Candida species has increased in the recent years. Species identification of the agents is necessary from the viewpoints of continuous epidemiological survey and susceptibility or resistance of different species to the antifungal drugs.Methods: In this study, forty eight clinical isolates of Candida species obtained from blood specimen cultures belonging to 32 immunocompromised patients with candidemia who were hospitalized in some therapeutic centers in Tehran, Iran, were precisely identified at the species level by a set of PCR-RFLP assays.Findings: C. parapsilosis was the most frequent agent of candidemia followed by C. glabrata, C. albicans, C. tropicalis and C. kefyr. These findings were unexpected and should be specifically mentioned because C. albicans is almost always the most common cause of candidemia and all other clinical forms of candidiasis, while among the isolates of the current study it only ranked third in terms of abundance.Conclusion: We found that C. parapsilosis as the most common causative agent of candidemia in our samples. Considering the relatively low number of studied isolates, it seems that a larger study is needed to confirm these results.

Keywords


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