Electronic equipment and appliances in special wards of hospitals as a source of azole-resistant Aspergillus fumigatus: a multi-centre study from Iran.

BACKGROUND: Azole-resistant Aspergillus fumigatus (ARAf), reported as a global public health concern, has been unexpectedly observed in different countries. AIM: To identify ARAf and detect azole resistance related to the CYP51A mutation in different hospital environmental samples. METHODS: In this multi-centre study from Iran, surfaces of electronic equipment and appliances from different hospitals in Iran were sampled using cotton swabs. All samples were cultured using azole-containing agar plates (ACAPs). Recovered Aspergillus isolates were identified at the species level using partial DNA sequencing of the ß-tubulin gene. The azole susceptibility testing of A. fumigatus isolates was performed using the Clinical and Laboratory Standards Institute M38-A3 guideline. The sequencing of the CYP51A gene was also performed to detect mutations related to resistance. FINDINGS: Out of the 693 collected samples, 89 (12.8%) Aspergillus species were recovered from ACAPs. Aspergillus fumigatus (41.6%) was the most prevalent, followed by A. tubingensis (23.6%) and A. niger (15.6%). Among 37 isolates of A. fumigatus, 19 (51.3%) showed high minimum inhibitory concentration (MIC) values to at least one of the three azoles, voriconazole, itraconazole, and posaconazole. CYP51A polymorphisms were detected in all 19 isolates, of which 52.6% showed the TR34/L98H mutation. Other detected mutations were G432C, G448S, G54E/G138C, F46Y, and Y121F/M220I/D255E. T289F and G432C were the first reported mutations in ARAf. CONCLUSION: There was a considerable level of azole resistance in hospital environmental samples, a serious warning for patients vulnerable to aspergillosis. Our findings have also revealed a different mutation pattern in the CYP51A gene.

In vitro antifungal activities of Actinomyces species isolated from soil samples against Trichophyton mentagrophytes.

BACKGROUND AND PURPOSE: Cutaneous infections arise from a homogeneous group of keratinophilic fungi, known as dermatophytes. Since these pathogenic dermatophytes are eukaryotes in nature, use of chemical antifungal agents for treatment may affect the host tissue cells. In this study, we aimed to evaluate the antifungal activity of Actinomyces species against Trichophyton mentagrophytes (abbreviated as T. mentagrophytes). The isolates were obtained from soil samples and identified by polymerase chain reaction (PCR) technique. MATERIAL AND METHODS: In total, 100 strains of Actinomyces species were isolated from soil samples in order to determine their antagonistic activities against T. mentagrophytes in Kerman, Iran. The electron microscopic study of these isolates was performed, based on the physiological properties of these antagonists (e.g., lipase, amylase, protease and chitinase), using relevant protocols. The isolates were identified using gene 16S rDNA via PCR technique. RESULTS: Streptomyces flavogriseus, Streptomyces zaomyceticus strain xsd08149 and Streptomyces rochei were isolated and exhibited the most significant antagonistic activities against T. mentagrophytes. Images were obtained by an electron microscope and some spores, mycelia and morphology of spore chains were identified. Molecular, morphological and biochemical characteristics of these isolates were studied, using the internal 16S rDNA gene. Active isolates of Streptomyces sequence were compared to GenBank sequences. According to nucleotide analysis, isolate D5 had maximum similarity to Streptomyces flavogriseus (99%). CONCLUSION: The findings of this study showed that Streptomyces isolates from soil samples could exert antifungal effects on T. mentagrophytes.