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Background Fungi are ubiquitous in the environment, and for patients with risk factors, they can present as pathogens. Unusual fungi often pose a diagnostic challenge and when encountered in practice, albeit infrequently, can delay diagnosis and treatment. Methods Over a period of three years (2018-2020), such cases were followed up till death or discharge and all details were noted down. All patients were diagnosed to have invasive fungal disease according to the EORTC/MSG criteria. Species identification was performed using MALDI-TOF MS and antifungal susceptibility testing (AFST) was done using standard CLSI guidelines. Results A total of 14 cases of rare yeasts were noted out of a total of 155 infections due to yeasts. Among these 5 presented with fungemia and 9 with invasive fungal infections (IFI). Of the IFI clinical isolates, there were 2 pus samples and 7 sterile fluids. The majority of these 14 patients were male (11) and belonged to extremes of age (8). The risk factors included CKD (2), prior history of tuberculosis (2), CLD (1), congenital heart disease (2), and type 2 diabetes mellitus (1). Pathogens isolated were Candida guilliermondii (2), Candida pelliculosa (2), Lodderomyces elongisporus (1) from the blood samples, and Trichosporon asahii (6), Candida guilliermondii (1), Candida kefyr (1), and Geotrichum spp. (1) from the other samples. Certain Candida species showed higher MICs to azoles and echinocandins. Trichosporon and Geotrichum showed higher MICs to azoles. Unfortunately, half of the patients (7) received no antifungals. Of those who did, 4 received mono therapy with azoles or Amphotericin B, while other 3 received combination or sequential therapy with azoles, echinocandins and Amphotericin B. Of the 14 patients, 3 patients expired. The etiological agents in these cases were Candida pelliculosa (fungemia) and Trichosporon asahii (IFI, 2 cases). Conclusion This study aims to highlight the clinical presentation of uncommon yeasts, presenting both as bloodstream infections (BSI) and as invasive disease. Improved methods of detection will help us improve our diagnostic accuracy of uncommon pathogens. The clinician should liaise closely with the laboratory, and treatment should be instituted according to the AFST data. Disclosures All Authors: No reported disclosures.

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM Objectives To report a case of Lodderomyces elongisporus fungemia in a late post-operative patient with the ventricular septal defect. Methods Informed consent was obtained from the parents of the child. Clinical history was collected. Routine biochemical tests were conducted. Blood samples were sent to the bacteriology and mycology laboratory for culture. Radiological examination of the head was done to ascertain the cause of neurological manifestations. Results An 11-year-old boy, previously diagnosed as a case of ventricular septal defect (VSD) and severe aortic regurgitation, had undergone VSD closure in December 2010 and aortic valve replacement in January 2011. He was discharged on oral anticoagulants. However, he did not follow up. In August 2018, he presented with fever and right-sided hemiparesis. Hemogram was within normal limits except for decreased hemoglobin. Bacteriological blood culture was sterile, but I.V. antibiotics were administered empirically. However, the patient started to have epileptic attacks and therefore was intubated and antiepileptics were administered. An NCCT of the head revealed a large intraparenchymal bleed. Echocardiography revealed intra-cardiac vegetation measuring 8 × 7 mm and moderate aortic regurgitation. Fungal blood culture inoculated in BACTEC Mycosis IC/F bottle flagged positive after 5 days of incubation. A smear and Gram stain from the same revealed budding yeast cells. Sub-culture was done on Sabouraud dextrose agar and HiCromeTM Candida Differential Agar, and blue-tinged colonies were observed on the latter. The isolate was identified as L. elongisporus when subjected to MALDI-TOF analysis. Identification was confirmed by sequencing the internal transcribed spacer (ITS) region of the ribosomal DNA. Antifungal susceptibility test was performed by broth microdilution as per CLSI guidelines. Antifungal therapy was initiated with liposomal amphotericin B, but he continued to have fever even after 1 week and consequently developed status epilepticus. CT scan of the brain revealed massive intracranial hemorrhage. Parents were advised neurosurgery, but they requested discharge against medical advice. The patient was lost to follow-up. Conclusions Lodderomyces elongisporus is a rare cause of invasive bloodstream infections and should not be ignored as a contaminant when isolated from sterile sites. It is often misidentified as Candida parapsilosis by conventional methods and commercially available systems but can be distinguished from it using chromogenic culture media and MALDI-TOF-MS. The current case report highlights the significance of L. elongisporus as a rare cause of invasive fungal infections, the difficulties faced in the identification of this pathogen, and the importance of newer diagnostic methods in identifying it.

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.

Introduction.Invasive mucormycosis (IM) is a life-threatening infection caused by fungi belonging to the order Mucorales. Histopathology, culture and radiology are the mainstay of diagnosis but lack sensitivity, leading to a delay in timely diagnosis and intervention. Recently, PCR-based approaches have been shown to be a promising method in diagnosing IM.Hypothesis/Gap Statement.Molecular-based approaches may be a valuable adjunct to standard conventional methods for diagnosing IM, especially among culture negatives and patients on antifungal therapy.Aim.In the present study we aimed to evaluate the clinical utility of panfungal and Mucorales-specific PCR for diagnosing IM from various clinical specimens.Methodology.This was a prospective study in which 239 clinically suspected cases of IM attending our tertiary care hospital from August 2015 to March 2018 were enrolled. All the cases were defined as ‘proven’, ‘probable’ or ‘possible’ based on EORTC/MSGERC guidelines. In addition to conventional diagnostics (KOH-calcofluor stain and culture), panfungal and Mucorales-specific PCR assays were also performed. The amplified products were sequenced for species identification.In vitroantifungal susceptibility was performed on all the culture-positive isolates.Results.Among 239 clinically suspected cases of IM, only 140 cases were diagnosed by the demonstration of aseptate ribbon-like hyphae on direct microscopy. Culture was positive in 35.7 % (54/140) of direct microscopy-positive samples. Among the proven cases (n=11), the sensitivity for both Mucorales-specific nested PCR and panfungal PCR was 100 %, but specificity was 91.9 and 73.7% respectively. In probable cases (n=129), the sensitivity of both the PCRs was 98.5 % and specificity for panfungal PCR was 73.7 and 91.9 % for Mucorales-specific PCR.Conclusion.Pan fungal PCR in combination with Mucorales-specific PCR, followed by sequencing, may play a significant role in IM diagnosis especially among those negative for both direct microscopy and culture.