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Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Aim To study the ecology, evolution, and resistance mechanism of Candida auris, using samples from patients, healthcare workers, hospital and environmental niches, using amplified fragment length polymorphism (AFLP) and antifungal susceptibility testing (AFST). Methods A total of 720 samples were screened for C. auris, including clinical samples from patients (tissue, body fluids), surveillance samples from patients (axillar/groin swabs), swabs and water samples from environmental locations and objects, surface swabs from hospital locations, and screening samples from healthcare personnel for hand carriage of C. auris. Samples were cultured on Sabouraud Dextrose agar (SDA) and CHROMagar. Colonies morphologically suggestive of C. auris were identified by Matrix Assisted Laser Desorption-Time of Flight (MALDI-TOF) and isolates were subjected to antifungal susceptibility testing (AFST) by broth micro-dilution method. DNA was extracted for analysis by amplified fragment length polymorphism (AFLP) and cluster analysis. The amplicons were subjected to capillary electrophoresis and fluorescent amplified length polymorphism (FALP) for the generation of a heat map and dendrogram to evaluate single nucleotide polymorphisms and single nucleotide variations (SNPs and SNVs). Results Out of 720 samples, C. auris was isolated and identified by MALDI-TOF from 50, including 37 from routine patient samples, 12/674 axillar/groin surveillance swabs, and 1/66 samples from hands of healthcare workers. C. auris was not isolated from any environmental samples or hospital surfaces. AFST revealed high overall rates of resistance to three important antifungal drugs−93.22%, 38.98%, and 52.54% of isolates were resistant to fluconazole, voriconazole, and amphotericin B respectively. Resistance to echinocandins was lower−1.81% of isolates were resistant to caspofungin, and micafungin. Additionally, 18 isolates showed only intermediate sensitivity to both voriconazole and caspofungin. The highest rates of resistance to amphotericin B, and azoles were observed in isolates from blood (62.5% of isolates) and axillar/groin swabs (44.5% of isolates) respectively. Resistance to caspofungin was seen in 14.28% of isolates from both groups. AFLP and capillary electrophoresis of extracted DNA revealed 188 variations in the range of 300-662 nucleotides. A total of 10 samples had no change in the nucleotides and were labeled as ‘constant’. The dendrograms generated by bioinformatic analysis of FALP results yielded two different clusters provisionally designated as cluster I and cluster II. Cluster I could be further distinguished into sub-cluster Ia and sub-cluster Ib, indicating further variations. Conclusions Candida auris is a pathogen of emerging importance in our center, with significant levels of resistance to several important antifungal drugs. Incidence of both the pathogen and antifungal drug resistance was observed in samples collected from patients, but not from the hospital or environment, and minimally from healthcare personnel. This suggests that the source of most C. auris infections is colonizers from the patient rather than environmental sources or healthcare workers, and infection control measures should be tailored accordingly.

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Objective Candida albicans is the major cause of fungal UTI in neonates and infants but nowadays incidence of other species of Candida is also increasing, and these are mostly multidrug resistant. It is, therefore, important to determine the causative Candida species in fungal UTI for appropriate management. This study was undertaken to determine the Candida species distribution in UTI along with susceptibility patterns and outcomes in infants and neonates admitted to various wards and intensive care units (ICUs) of our hospital. The incidence rate of candiduria in ICUs was also assessed. Method Urine samples were collected from infants and neonates presented in pediatric and neonatal ICUs and clinical wards with a clinical suspicion of candiduria. Infants at risk of invasive candidiasis were also included in the study. Identification of Candida species was done by Gram's staining, germ tube test, chlamydospore formation on corn meal agar, color of colonies on CHROMagar, and confirmed by Matrix Assisted Laser Desorption-Time of Flight (MALDI-TOF). Antifungal susceptibility was performed by using the Broth microdilution method as per the latest CLSI guidelines (M27-A3/M27-S4). Result Urine samples were received from 219 infants, and Candida was isolated from samples from 52 infants (isolation rate 23.75%), of which 30 were admitted to pediatric or neonatal ICU and 22 in the wards. The incidence rate of candiduria in ICU was 3.25%. Candida albicans was the most frequently isolated species from the samples of infants in the wards (13/22 ie, 59%), while Candida tropicalis was most frequently isolated from samples of infants in the ICUs (13/30 ie, 43.34%). Candida glabrata was the least commonly isolated species and was only encountered in the ICU. The species distribution of isolates is given in Table 1. There was no discrepancy between the results of conventional methods of identification and MALDI-TOF. Antifungal susceptibility was performed for 18 randomly selected isolates. All were found to be susceptible to caspofungin, micafungin, itraconazole, voriconazole, fluconazole, and amphotericin B. MIC distribution for various isolates is given in Table 2. Conclusion High index of suspicion of candiduria is necessary for early diagnosis of fungal UTI and initiation of antifungal treatment, especially in critically ill infants requiring intensive care. Species other than C. albicans are also encountered more frequently nowadays and these species often have higher MICs for commonly used antifungal drugs, which may lead to delayed or failed response to routine antifungal therapy and necessitate prolonged use and or higher doses of antifungals. Identification of Candida isolates at species level along with analysis of the susceptibility patterns is therefore important for successful outcomes in candiduria in neonates and infants.