bluuebunny/crossref_metadata_2025_split huggingface dataset:
P358 Candida auris survival on common medical supply surfaces under different environmental conditions
Authors: Khodadadi Hossein , Taghizadeh Mohammad , Zomorodian Kamiar , Nasr Reza , Hosseinpour Salar 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Background
Candida auris is an emerging multidrug-resistant pathogenic yeast. The increasing frequency of C. auris outbreaks is prompting alarm worldwide. This yeast survives and spreads on contaminated medical supplies, resulting in hospital outbreaks. To learn more about the yeast's spreading behaviors and transmission, we studied its persistence and survival on a variety of medical-related surfaces under diverse environmental conditions.

Methods
A total of 104 CFU/mL solutions of four Candida species, including C. auris, C. albicans, C. parapsilosis, and C. glabrata, were inoculated onto different 2 × 2 cm sheets of cotton textile, polystyrene, paper, aluminum, glass, latex, and dried Sabouraud dextrose agar. Inoculated sheets were incubated at various temperatures and subjected to light and darkness at 1, 2, 7, 14, 30, 45, 60, and 120-day intervals. After culture of the sheets on Sabouraud dextrose agar plates, the viable CFUs of yeasts were counted.

Results
All four species remained alive on all surfaces for at least 1 week under ambient and refrigerator temperatures, darkness, and light exposure. However, only latex and polystyrene surfaces maintained viable C. auris and C.parapsilosis for a maximum of 30 days at ambient temperature and darkness. C. auris survived on dried Sabouraud dextrose agar sheets for ˃4 months.

Conclusions
Candida auris and other pathogenic yeasts can survive on a variety of medical surfaces for extended periods of time. Latex and polystyrene devices are the best medical matrices for yeast persistence. If C. auris has access to organic and nutritional components, its survival could be greatly increased. To prevent C. auris transmission, appropriate disinfection and decontamination methods should be considered.
P364 Quantitative monitoring of Aspergillus fumigatus mycelial growth by optical density
Authors: Miyazawa Ken , Umeyama Takashi , Hoshino Yasutaka , Takatsuka Shogo , Muraosa Yasunori , Abe Keietsu , Miyazaki Yoshitsugu 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Objectives
Filamentous fungi generally form hyphal pellets in liquid culture. This property prevents filamentous fungi from applying the growth monitoring methods used for unicellular organisms such as yeast and bacteria. We have analyzed the biological functions of cell wall polysaccharide α-1,3-glucan and extracellular polysaccharide galactosaminogalactan (GAG) in Aspergillus species, and revealed that both α-1,3-glucan and GAG contribute to the pellet formation. Here we constructed the double disruption mutant of α-1,3-glucan and GAG biosynthesis-related genes (Δags1Δgtb3) in Aspergillus fumigatus AfS35 strain, and used the mutant for quantitative monitoring of the mycelial growth by optical density.

Methods
To measure the optical density of conidia and mycelia in shake-flask culture, conidia (final concentration, 1.0 × 10⁷/ml) of AfS35 or Δags1Δgtb3 strain were inoculated into 50 ml of Aspergillus minimal medium (AMM) medium in a 200-ml Erlenmeyer flask and rotated at 160 rpm at 37°C. At each sampling point, the culture (2 ml) was withdrawn, and 100 μL of the culture was mixed with 100 μL of 4% paraformaldehyde solution in a 96-well plate. OD₆₀₀ was measured in a microplate reader. To evaluate the susceptibility of the Δags1Δgtb3 strain to antifungal agents, conidia (final concentration, 5.0 × 10⁶/ml) were inoculated into 500 μL of RPMI medium containing an antifungal agent (voriconazole, itraconazole, amphotericin B, flucytosine, or micafungin) in a 48-well plate and rotated at 300 rpm using a microplate mixer at 35°C for 15 h, and OD₆₀₀ was measured in triplicate.

Results
In AMM flask culture, pellets became visible in AfS35 from 9 h, and their size increased with time, whereas the Δags1Δgtb3 hyphae were continuously dispersed (Fig. 1a). The OD₆₀₀ measurements of AfS35 suggested no correlation between apparent AfS35 growth and OD₆₀₀ (Fig. 1b). In the Δags1Δgtb3 strain, the first and third quartiles were 0.633 and 0.595 at 15 h (Fig. 1b), suggesting that the measurement of OD₆₀₀ is suitable for monitoring the growth of the mutant. As an application of the monitoring method, the Δags1Δgtb3 strain was grown in an RPMI medium containing the indicating antifungal agent for 15 h in a 48-well plate (Fig. 2). Growth was repressed in the presence of antifungal agents tested, except for micafungin (Fig. 2). Growth was completely inhibited at 2 μg/ml of voriconazole, 1 μg/ml of itraconazole, 0.5 μg/ml of amphotericin B, and 256 μg/ml of flucytosine (Fig. 2), which was in agreement with MICs determined by CLSI M38-A2.

Conclusion
We established a convenient strategy to monitor A. fumigatus hyphal growth. Our method can be directly applied to screening for novel antifungals against Aspergillus species.
P366 Role of the Sit1 siderophore transporter in iron uptake, germination, and virulence of Mucor lusitanicus
Authors: Nagy Gábor , Vágó Bernadett , Bauer Kitti , Rafael Bence , Szebenyi Csilla , Vágvölgyi Csaba , Papp Tamás 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM
Mucormycosis is a life-threatening systemic infection caused by certain members of the filamentous fungal order Mucorales (e.g., Rhizopus delemar, Lichtheimia corymbifera, and Mucor circinelloides). Mucormycosis is associated with a high mortality rate, which can be nearly 100% depending on the underlying condition of the patient. One of the main risk factors of mucormycosis has been the iron-chelating treatment. Iron is an essential nutrient for both the host and the pathogen. Therefore, organisms developed various strategies to acquire iron from the environment. Three strategies are available to microorganisms to uptake iron from the environment: acidification of the environment, reduction of ferric iron to the more soluble ferrous form, and secretion of soluble iron-chelating molecules. All fungi produce hydroxamate-type siderophore, except Mucorales fungi, which secrete a polycarboxylate siderophore, rhizoferrin. However, they also can utilize hydroxamate siderophores as xenosiderophores.

In the Mucor genome database, one putative sit1 gene encoding a ferrioxamine B transporter, which belongs to the ARN/SIT subfamily of the major facilitator superfamily (MFS), coding was found. In Saccharomyces cerevisiae, Candia albicans, and Aspergillus fumigatus, siderophore-iron chelates are taken up through Arn3/Sit1 transporters. The relative transcript level of sit1 gene was measured after iron-starvation, and different siderophore treatments using quantitative real-time PCR. We have started to create and characterize (growth and germination ability, in vivo virulence assay, etc.) a sit1 knock-out mutant constructed using a CRISPR-Cas9 system.

Sit1 gene showed significantly increased transcript levels using deferoxamine-iron, deferasirox-iron, and enterobactin-iron complexes. The colony diameter of the mutant strain was measured on Blood and Cas agar with (CasFe) or without iron (Cas-Fe). On CasFe agar, the growth ability of the mutant was significantly decreased compared to the control strain. In Galleria mellonella model, disruption of the sit1 gene resulted in decreased virulence. Relative transcript level of the putative rhizoferrin synthase gene (rfs) was measured in the sit1 knock-out mutant, where the gene showed an increased transcript level.

Our result suggested that Sit1 is required for germination and virulence of Mucor lusitanicus and it may influence rhizoferrin production.

This study was supported by the NKFI project K131796 and the grant ITM NKFIA TKP-2021-EGA-28. GN is grateful for the support of the Premium Postdoctoral Fellowship Program of the Hungarian Academy of Sciences (460 050).
P369 Aspergillus spp. in coastal environments with different salinity
Authors: Andrade Emília , Poester Dr Vanice , Hidalgo Jéssica , Souza Dr. Manuel , Bennelli Dr. Jéssica , Xavier Prof. Melissa 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM
Aspergillus is a fungus genus found in several environments due to its ubiquitous characteristic. The emergent antifungal resistance of these fungi and their relation with animal and human pathogens turned necessary a One Health approach, which unites animal, human and environmental health as one. In this context, the ocean can be an inhospitable environment in view of the high salinity and other variables like pH and temperature, however, Aspergillus spp. is reported as a pathogen of marine animals, and the ocean can be a reservoir and/or creator of resistant strains considering the unfavorable conditions found there.

Objective
We aimed to evaluate the seasonal frequency of Aspergillus spp. In different coastal environments in southern Brazil.

Methods
Samples of surface water were collected monthly from July 2021 to April 2022 at three coastal environments in the municipality of Rio Grande/RS. The locations were 1) Lagoonal system/Lagoa dos Patos (−32.0253°S, −52.1060°W); 2) Lagoon mouth (−32.1495°S, −52.1009°W) and 3) Sea/Cassino beach (−32.2066°S, −52.1738°W). Water samples (1000 ml) were collected in sterile bottles, refrigerated and cultured within 12 h. An adapted technique of filtering membrane (0.45 μm) culture by vacuum filtration system was performed. Briefly, after filtration, the membrane was transferred to a falcon tube with 10 mL of sterile saline and vortexed (3 min) for elution. Subsequently, the membrane was disposed of on Sabouraud-dextrose (SDA) plates with gentamicin and chloramphenicol (SDAGC). The resulting elution was centrifuged at 3500 rpm (3 min) and the precipitate (500 μL) was also cultured in duplicate by spreading on SDAGC plates. Plates were incubated at 30°C for 7 days, being evaluated daily for fungal growth. Aspergillus spp. were identified at section level by macro and micromorphological characteristics. The determination of the water salinity in the samples was performed with a YSI multiparameter (ProDSS).

Results
The average salinity of the water samples (n = 10) was 18.57 PSU (SD = 14.58) at point 1 (Lagoon), 19.45 PSU (SD = 14.95) for the point 2 (Lagoon mouth), and 31.31 PSU (SD = 3.18) for point 3 (Sea). Aspergillus spp. Was isolated in 23%, 37%, and 40% of the samples at points 1, 2 and 3, respectively. A total of 30 isolates were obtained, being 13 section Fumigati, 10 Flavi, 6 Nigri, and 1 Terrei. In point 1 and 2, the Fumigati section predominated (57% and 54%, respectively). On the other hand, at point 3, section Flavi (41%) predominated, with Fumigati corresponding to just 25%.

Conclusion
Although pathogenic Aspergillus sections can be isolated from environments with distinct salinities, the section Fumigati seems to be less frequent in higher salinity places. Their antifungal susceptibility profile will be tested prospectively.
P372 Deciphering transcript isoform switching and utilization in mature biofilm of Candida glabrata through a global transcriptomic approach
Authors: Raj Khem 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Objective
Eukaryotic cellular systems utilize alternative transcript isoforms generated via an isoform switching mechanism to thwart various stress conditions. To the best of our knowledge, transcript isoform switching and differential transcript isoform usage (DTU) in Candida glabrata have not been studied. Therefore, the present study was designed to delineate differential transcript isoform expression (DTE) and transcript isoform switching followed by DTU and the functional impact of transcripts in a mature biofilm of C. glabrata (clinical isolate; NCCPF 100037) through an RNA sequencing approach.

Results
DTE analysis generated 7837 transcript isoforms from the C. glabrata genome (5293 genes in total), and DTU investigations revealed that transcript isoforms of 292 genes were specifically utilized in the formation of mature biofilms via the isoform switching process. Gene Ontology/pathway analysis and protein-protein interactions further substantiated the functional attributes of switched transcript isoforms selectively used by C. glabrata in biofilm formation and survival.

Conclusion
The present study elucidates that specific transcript isoforms utilized in mature biofilms of C. glabrata could be used as potential targets for the development of novel antifungal therapeutics.
P399 Diagnostic value of Candida coloni zation index and serum Candida mannan antigen for candidemia in febrile episodes of pediatric lymphoreticular malignancies
Authors: Gautam Suchita , Das Shukla , Saha Rumpa , Singh N. P. , Gomber Sunil , Rai Gargi , Singh Praveen 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Objective
To evaluate the diagnostic performance of Candida colonization index and serum Candida mannan antigen predicting candidemia in febrile episodes of pediatric lymphoreticular malignancies

Methods
It was a prospective observational study done for 18 months, from November 2018 to April 2020 at the pediatric oncology unit of a multispecialty tertiary care center. Based on our patient load, duration of the proposed study, and available resources, a sample size of 49 (n = 49) was decided and 100 febrile episodes in children with lymphoreticular malignancy were studied. Children below 12 years, receiving chemotherapy for hematological malignancy having oral or axillary temperature ˃38.3°C for ˃1 h were included in this study. Children receiving the antifungal treatment in last 7 days were excluded from the study. Blood collected on day1 and day4 was cultured in BACTEC-9120. For colonization, swabs and samples were collected and cultured on SDA on day1, day4, and day8. All Candida isolates were subcultured on SDA and subjected to Gram's stain, germ tube test followed by Microscan identification. DNA sequencing followed by phylogenetic analysis was done for all the isolates of Candida recovered from blood. Antifungal susceptibility of yeast stains was done. Serum collected on day1 was used for C. mannan antigen detection using ELISA system.

Results
Prevalence of candidemia was 5%. Non-albicans Candida spp were isolated from blood cultures on day 4. Candida colonization decreased from day1 to day8. Colonization index (CI) day1 showed 80% sensitivity 98.9% specificity, and 98.9% negative predictive value. Significant colonization (CI ≥0.5) was seen in a larger proportion of cases that developed candidemia. There was a significant association of Candida colonization (CI ≥0.5) with occurrence of candidemia on day1 and day4. A total of 4 (80%) of candidemia episodes were positive for serum mannan antigen while 1 (20%) was negative. Mannan antigen was detected earlier with 80% sensitivity, 92.6% specificity, and 98.9% negative predictive value. All Candida isolates were sensitive to fluconazole, amphotericin-B, and caspofungin.
Receiver operator characteristic curves for diagnostic performance of various parameters in predicting candidemia show the following trends:

Conclusion
The CI can predict candidemia but the threshold value needs to be explored in pediatric patients with lymphoreticular malignancies. Mannan antigen detection gives early results with a high negative predictive value.
P414 Diagnostic allele-specific PCR for the identification of Candida auris clades and common resistance mutations
Authors: Carolus Hans , Jacobs Stef , Romero Celia Lobo , Deparis Quinten , Cuomo. Christina A. , Meis Jacques F. , Van Dijck Patrick 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM
Candida auris (C. auris) is an opportunistic pathogenic yeast that emerged worldwide during the past decade. This fungal pathogen poses a significant public health threat due to common multidrug resistance (MDR), alarming hospital outbreaks, and frequent misidentification. Genomic analyses have identified five distinct clades that are linked to five geographic areas of origin and characterized by differences in several phenotypic traits such as virulence and drug resistance.

Typing of C. auris strains and the identification of clades can be a powerful tool in molecular epidemiology and might be of clinical importance by estimating outbreak and MDR potential. As C. auris has caused global outbreaks, including in low-income countries, typing C. auris strains quickly and inexpensively is highly valuable. We report five allele-specific multiplex polymerase chain reaction (AS-multiplex PCR) assays for the identification of C. auris and each of the five described clades of C. auris based on conserved mutations in the internal transcribed spacer (ITS) rDNA region and a clade-specific gene cluster. Additionally, we developed AS-PCR assays for the identification of SNPs in FKS1 and ERG11 that are commonly linked to echinocandin and azole resistance respectively.

This PCR method provides a fast, cheap, sequencing-free diagnostic tool for the identification of C. auris, C. auris clades, and common resistance mutations.
P415 High positive and rapid detection of clinical urine samples of fungal infection based on modified calcium fluorescence
Authors: Chen Biao , Shi Dongmei 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Successful management of urinary fungal infection depends upon the detection positive and efficiency. The aim of this study was to evaluate the detection positive and efficiency of modified calcium fluorescent white (m-CFW) staining in direct detection of Candida spp. in urine samples of patients with suspected fungal infection. We collected 100 clinical urine samples from different departments and analyzed the detection positive rate of the methods of culture, KOH, sequence, and modified CFW. The results indicated that the positive rate of the methods was 12%, 8%, 14%, and 15%, respectively. The positive rate of modified CFW staining was significantly higher than that of ordinary microscopic examination and fungal culture (P &lt;.05). Modified CFW in the detection of fungi in urine can significantly improve the positive rate of fungi in clinical urine samples and shorten the detection time. It has a certain reference value for clinical diagnosis and medication.
P430 Correlation of microscopy and culture findings with serum ferritin level for the diagnosis of rhino-orbito-cerebral Mucormycosis during COVID-19 pandemic—a study from tertiary care hospital India
Authors: Lakshmanan Jothisri , Das Shukla , Singh Narendra Pal 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Objectives
Rhino-orbito-cerebral Mucormycosis (ROCM) is a fulminant manifestation with high morbidity and mortality rates. It was considered to be a notifiable disease during COVID-19 pandemic in India as per ICMR. Hence, this study was conducted to correlate microscopy (KOH) and culture findings with serum ferritin levels for the cases with suspected ROCM with diabetes mellitus (DM) as a primary risk factor presented to tertiary care hospitals in India during COVID-19 pandemic.

Methods
A prospective study was conducted during the COVID-19 second wave in 2021. Total 134 cases of suspected ROCM with DM were included in the study. Various types of samples received from Oto-rhino-laryngology department such as nasal crust, swab, secretions, lavage, biopsy, etc. They were subjected to KOH wet mount as well as culture on Sabouraud Dextrose Agar (SDA) with antibiotics and cycloheximide. Simultaneously serum samples were collected from all the patients for serum ferritin analysis. All of their COVID-19 status, Microcopy (KOH), and Culture findings were analyzed and correlated with serum ferritin levels.

Results
Of the 134 suspected ROCM cases with diabetes mellitus as a comorbidity, both KOH and culture positive for Mucorales such as Rhizopus species, Mucor species, Cunninghamella species, was 21.6% whereas KOH positive for Mucorales and culture positive for mixed growth such as Aspergillus species, Alternaria species, Bipolaris species, etc. was 10.4%. Serum ferritin level has been tested for all the cases and it is found to be increased by about 93%. Among these cases, 72% were confirmed COVID-19 positive. The mean age of these suspected ROCM patients was 62.3years, males were significantly more affected than females.

Conclusion
Microscopy (KOH) and culture are the mainstays of the diagnosis of ROCM. Besides diabetic ketoacidosis as the primary underlying risk factor, high serum ferritin level was appeared to be an additional factor for the severity and manifestations of the disease.
P438 Epidemiology, risk factor analysis and management of invasive Candida auris infections in tertiary care hepatobiliary center in India
Authors: Patel Niharika , Kale Pratibha , Khillan Vikas , Sarin Shiv Kumar 
Published: September 2022

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Objectives
Candida auris (C. auris) infections are associated with misidentification, intrahospital transmission, poor treatment outcomes, and higher mortalities. Prompt detection, earlier initiation of therapy and effective surveillance can curtail C. auris in hospitals. We aimed to study epidemiology, risk factors, and therapeutic management of invasive infections caused by C. auris in patients with hepatobiliary diseases.

Methods
Single-center, prospective study of patients with suspected invasive fungal infections between January2017-December 2021 in the patients with hepatobiliary diseases. Demographics, comorbidities, and laboratory variables were recorded. The positive yeast cultures were identified by VITEK 2 (Biomerieux, India) and antifungal sensitivity confirmed by Broth microdilution in accordance with CLSI guidelines. The final outcomes considered were mortality within 1 month after diagnosis or discharge of the patient with stable parameters.

Results
Total of 189 isolates of C. auris from 73 patients, blood 25 (13.2%), abdominal fluids 29 (15.3%), urine 90 (47.6%), respiratory 7 (3.6%), liver abscess 2 (1.05%), pancreatic abscess 1 (0.5%), and wound infections 3 (1.5%). Underlying disease was chronic liver disease 49 (68%), 15 (20%) post liver transplant patients, acute on chronic liver failure 5 (7%), acute liver failure 2 (3%), acute pancreatitis 1 (1.3%), and pancreatic neuroendocrine tumor 1 (1.3%). 18 (25%) patients were discharged, the mortality was 54 (74.04%). Risk factors were MELD 40 (P .04), Child C (P .05), and CTP score above 12. Prior use of steroids (P .02), neutropenia (P .03), prolonged hospital stay (P .029), the use of broad-spectrum antibiotics ˃7 days (P .05) were the risk factors significantly associated with the development of C. auris infections, and higher mortality. Co-morbidities, acute renal failure, diabetes, and hepatitis infection were not significantly associated with mortality. The antifungal resistance: fluconazole 68.42%, voriconazole 14.03%, flucytosine 59.64%, and amphotericin B 28% with no resistance to caspofungin and micafungin.

Conclusion
Our study depicts the spectrum of invasive infections caused by C. auris, its prevalence, risk factors, and therapeutic options. The presence of risk factors, steroid use, neutropenia, broad-spectrum antibiotic use, and a hospital stay of ˃7 days should prompt toward escalating diagnostic measures for rapid identification of C. auris for early initiation of therapy. Active screening of patients with risk factors can also reduce mortality. The study results also help to guide empiric therapy with echinocandins as azoles and amphotericin B show high resistance in these isolates.