P045 The association of performance of air pollutants on Candida drug resistance

Abstract Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Objective Therapeutic methods are very important in the prevalence of opportunistic fungal infections, which are among the main causes of human diseases. In this study, air pollution agents that are in direct contact with microorganisms and as a carbon source using CO2 and MTBE and their effects on aspects such as growth and particularly the evaluation of changes in the expression of interfering genes in susceptibility and drug resistance in these fungi were investigated. Materials and Methods Collecting samples and isolating Candida glabrata (C. glabrata) and Candida albicans (C. albicans) with phenotypic methods were accomplished. In this way, evaluating the minimum inhibitory concentration (MIC) with M27A4 protocol of CLSI was done. Adjusting to sensitive strains from the MIC test, which included 20 C. albicans and 10 C. glabrata which were sensitive to fluconazole and itraconazole drugs with 5% CO2 and 5 mg/ml MTBE interfering agents that are considered as air pollutants and also re-evaluating MIC testing to separate strains resistant to azole drug were accomplished. Results Up-regulation of some genes on two mentioned yeast had led to drug resistance in them, which were previously sensitive to both drugs. Correspondingly, 41% of C. glabrata samples in sputum showed sensitivity to these drugs. Up-regulation of ERG11(71%) and EPA1 (90%) were observed in resistant strains. Up regulation of genes associated with aspartate proteins and down regulation of SAP3 genes were recognized in C. glabrata in sputum and a 15% down-regulation of BAL isolate and 50% up-regulation of SAP1 gene in C. albicans sensitive samples were observed and compared with fluconazole and itraconazole with oral and joint source. Remarkably, decreased SAP2 expression in oral sources and 60% increase in resistant strains in C. albicans was observed. The down-regulation of SAP3 expression showed in the joint samples. An increase in HWP1expression (30%) was noted in isolated and drug-sensitive samples at the sputum and BAL source. CDR1 expression was increased in MTBE-affected species however, it decreased in the vicinity of CT. Conclusion Air pollutants such as CO2 and MTBE eventually caused drug resistance in Candida, which can be one of the causes of drug resistance in candidiasis infections.