bluuebunny/crossref_metadata_2025 huggingface dataset:
P317 Phaeohyphomycosis caused by Phialophora verrucosa in a patient with CARD9 mutations
Authors: Zhang Lu , Zhang Yi , Wang Zijuan , Wang Xiaowen , Li Ruoyu
Published: September 2022

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM

 

Objectives

To study an intractable case of phaeohyphomycosis caused by Phialophora verrucosa and the underlying genetic and immunological mechanisms.

Methods

Clinical and laboratory findings of the patient were studied. The patient's DNA was sequenced for CARD9. Innate and adaptive immunological responses of patient-derived PBMCs were evaluated with ELISA and flow cytometry.

Results

A 29-year-old Chinese male, born to nonconsanguineous parents, developed an enlarging plaque on his right anterior tibia at 25 years and underwent a 15-month treatment of oral itraconazole at the local hospital. Upon discontinuation of the medication, the plaque spread over his face, upper limbs, and back. Physical examination indicated dark brown verrucous plaques and nodules with surface ulcers and scabs on his right leg, upper limbs, and face. Skin biopsy revealed pigmented yeast cells with budding and yeast cell chain in the dermis. Based on tissue culture, we identified P. verrucosa as the causative pathogen, which was further validated by ITS, BT, and TEF gene sequencing. Thus, subcutaneous phaeohyphomycosis was diagnosed, and itraconazole combined with amphotericin B was prescribed. The lesions improved only marginally. We, therefore, gave him oral posaconazole instead, based on in vitro antifungal susceptibility results. After 1 month of posaconazole treatment, the serum BG assay value decreased and the lesions improved markedly.

Based on previous reports linking CARD9 deficiency to phaeohyphomycosis, as well as early onset and recalcitrance characters, Sanger sequencing was performed in this patient and identified two compound heterozygous mutations in exon 6 (R373P) and exon 8 (D274GfsX60) of CARD9. We then evaluated the functional effect of the CARD9 mutations by assessing the stimuli-dependent release of proinflammatory cytokines and helper T cell differentiation. Cytokine production was markedly impaired in PBMCs post 24 h of stimulation with LPS, curdlan, TDB, mannan, MDP, β-glucan, and various fungal ligands. Moreover, the patient showed a significant absence in Th22 and Th17 cell proportions, as well as lower IL-17A and IL-22 production after six days of co-incubation with the stimuli mentioned above.

Conclusion

Our report highlighted that otherwise healthy patients diagnosed with early-onset, unexplained, and recalcitrant phaeohyphomycosis should be analyzed for CARD9 mutations and immune deficiency. Furthermore, posaconazole may be an alternative worth trying after the failure of other antifungals due to its ideal results achieved in our case.
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

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

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

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

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

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

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

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

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 <.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

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

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.
P439 Biomarker detection for the diagnosis of disseminated histoplasmosis in people living with HIV/ AIDS in Southern Brazil: a year of implementation
Authors: Blan Bianca , Basso Rossana , Poester Vanice , Benelli Jéssica , Sanchotene Karine , Xavier Melissa
Published: September 2022

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

 

Background

Disseminate histoplasmosis (DH) is an important opportunistic disease in HIV/AIDS patients.

Objective

We aimed to report partial results of the implementation of the Histoplasma urinary biomarker as a routine test for the diagnosis of DH in people living with HIV/AIDS (PLWHA) admitted to a reference hospital in Southern Brazil.

Methods

The study was performed in a tertiary hospital, which is recognized as a regional reference center to 21 cities for the treatment of PLWHA. At this service, since the beginning of 2021, a new protocol for DH investigation was adopted, including the systematic execution of urinary antigen test for histoplasmosis (Histoplasma GM EIA, IMMY®) in PLWHA. We retrospectively evaluated data from all of these patients diagnosed with DH in the last 1 year, between March 2021 and March 2022. The study was approved by our university ethics committee (CEP/FURG; N° 234/2018).

Results

Within the 12 months period, 243 patients from our hospital were investigated by Histoplasma GM EIA through urine samples. A total of 19 were diagnosed with DH through this test, resulting in a prevalence of 7.8%. Interestingly, nine of them were also investigated by antibody detection through immunodiffusion test (IMMY), being all negative in this serology. DH was the AIDS-defining illness in 21% of these patients (4/19), and co-infection with Mycobacterium tuberculosis was detected in 37% (7/19). Half of the patients (11/19) were severe immunosuppressed (CD4 + lymphocytes <100 cells/mm3), 21% (n = 4) had rates between 100 and 200 cells/mm3 and 21% (n = 4) had >200 cells/mm3. The majority of the patients (74%; n = 14) had advanced signs of DH, showing pulmonary impairment, weight loss, fever, neurological, and/or skin lesions and lymphadenopathy, suggesting late diagnosis, 16% (3/19) of the patients had few signs of DH (suggesting precocity), and two patients were diagnosed before the onset of the clinical manifestation, with the strategy of the use of GM Histoplasma EIA as a screening test. Although the antifungal treatment, five of them (35.7%) died.

Conclusion

The systematic use of the test to detect a specific biomarker in urine samples had improved substantially the diagnosis of DH in PLWHA in our hospital (19 cases in one year). In addition, since we could diagnose DH with precocity in five patients, we suggest that in regions where DH is hyperendemic, the GM Histoplasma EIA could be used as a screening test for all AIDS patients, similar to what is preconized to cryptococcal disease. More robust studies are instigated to evaluate this strategy, and its benefits to an early diagnosis, resulting in a better quality of life, better prognosis, and consequently reduction of the mortality rate.
P456 Defungi: direct mycological examination of microscopic fungi images
Authors: Álvarez María Alejandra Vanegas , Sopó Leticia , Sopo Camilo Javier Pineda , Hajati Farshid , Gheisari Soheil
Published: September 2022

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

 

Objective

To classify five fungi types using two different deep learning approaches and three different convolutional neural network models, VGG16, Inception V3, and ResNet50.

Method

A mycological laboratory in Colombia donated the images used for the development of this research work. They were manually labeled into five classes and curated with subject matter expert assistance. The images were later cropped and modified with automated coding routines to produce the final dataset.

Results

We present experimental results classifying five types of fungi using two different deep learning approaches and three different convolutional neural network models, VGG16, Inception V3, and ResNet50. The first approach benchmarks the classification performance for the models trained from scratch, while the second approach benchmarks the classification performance using pre-trained models based on the ImageNet dataset. Using k-fold cross-validation testing on the 5-class dataset, the best performing model trained from scratch was Inception V3, reporting 73.2% accuracy. Likewise, the best performing model using transfer learning was VGG16, with 85.04% accuracy.

Conclusion

The statistics provided by the two approaches create an initial benchmark to encourage future research work to improve classification performance. Furthermore, the dataset built is published on Kaggle and GitHub to encourage future research.
P463 Toxicological evaluation of Aureobasidum pullulans var. pullulans induced mycotoxicosis in amurine model
Authors: Kumari Ankita , Singh Karuna
Published: September 2022

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

 

Objectives

The genus Aureobasidium includes 14 species, amongst which Aureobasidium pullulans is the most well-known species. Aureobasidium pullulans, includes two well-documented varieties found in indoor environments and associated with health issues: A. pullulans var. pullulans and A. pullulans var. melanogenum. Aureobasidium pullulans is a mold belonging to the family Dothioraceae. It colonizes nails, hair, and skin in humans. Deleterious immune reactions may occur in humans, like hypersensitivity pneumonitis and allergies. Respiratory allergies may result due to high levels of Aureobasidium in the air. The metabolites of the mold, like mycotoxin, are known to cause toxic-irritant effects. In view of this, the present work evaluates the effects of the toxic secondary metabolites of A. pullulans var. pullulans (CBS 577.93) in a murine model.

In order to maximize the toxicological potential of A. pullulans pullulans (CBS 577.93) for the production of mycotoxins, an understanding of its mode of action in an animal model is necessary. In the present study, we report the mycotoxicological activity of A. pullulans pullulans (CBS 577.93) in experimental mice.

Material and Methods

Mycotoxins isolated from A. pullulans pullulans (CBS 577.93) were used for the experimental induction of mycotoxicosis in Swiss mice (C3HHC strain). The mycotoxin was administered intraperitoneally (IP) and intranasally (IN). To assess the toxic effects of the A. pullulans mycotoxins, eight organs, namely liver, lungs, kidney, spleen, stomach, heart, brain, and testis, were taken into consideration. The hematological, histopathological, and biochemical aspects of A. pullulans-induced mycotoxicosis were investigated.

Results

Conclusion

Thus, from the present study, we concluded that mycotoxins isolated from A. pullulans (CBS 577.93) documented toxicity in all eight organs, with the testis and lungs being the worst affected organs. Even at a very small concentration and short exposure, the mycotoxin caused severe damage to the vital organs. New risk assessment approaches should be considered to investigate the toxicological interactions of A. pullulans mycotoxins in the indoor environment and in animal models.
P480 A novel zincophore locus in Candida auris?
Authors: Chakraborty Tanmoy , Wilson Duncan
Published: September 2022

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM

Candida auris is an emerging multidrug-resistant human fungal pathogen that is spreading rapidly across the world and is associated with hospital-acquired invasive infections with high mortality rates. Whilst previous studies have focused on understanding the basic biology and drug resistance mechanisms of C. auris, nothing is known about the strategies underlying trace metal acquisition. Trace metals like zinc are known to be crucial for numerous biological functions across all kingdoms of life. Thus, in this study, we aimed to characterize the zinc uptake mechanisms of C. auris and determine their role in virulence. We compared the ability of C. auris to grow in zinc-restricted conditions with other pathogenic fungi belonging to the CTG and WGD clade. Regardless of the clade, we found that C. auris has a striking ability to grow under extreme zinc-limiting conditions when compared with other human pathogenic fungi.

 

Other fungi have been demonstrated to scavenge zinc via a zincophore locus, encoding a secreted zinc-binding protein Pra1 and its cognate receptor, Zrt101. However, in silico analysis of C. auris revealed that this species has undergone a rearrangement of the locus. The canonical zincophore gene PRA1 has translocated to another chromosome and the extracellular zinc-binding domain of the Zrt101 receptor has undergone an inverted duplication generating a novel putative zincophore.

 

Our qRT-PCR analysis demonstrated that both PRA1 and the novel zincophore genes were upregulated in response to neutral pH and zinc-restriction. Protein supernatant from C. auris strains also showed high zinc binding activity. Furthermore, we have generated mutants lacking the novel zincophore gene in C. auris by CRISPR/Cas9 and found that these deletion mutants exhibited perturbed growth under zinc limitation. Together our observations suggest that C. auris has evolved a unique zinc acquisition strategy from the environment and the host.
P489 Anti-granulocyte-macrophage colony-stimulating factor (Anti-GM-CSF) autoantibodies—the underrecognized cause of Cryptococcosis in non-HIV individuals in Thailand: Case series from a single tertiary care hospital
Authors: Pongdumbun Tuvanont , Treebupachatsakul1 Pornpit , Umrod Pinklow , Tantibhedhyangkul Wiwit , Chayakulkeeree Methee
Published: September 2022

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM

 

Background

Cryptococcosis is an opportunistic fungal infection in immunocompromised patients. Granulocyte-macrophage colony-stimulating factor (GM-CSF) regulates the functions of phagocytes and alveolar macrophages, which are crucial in cryptococcal control. Anti-granulocyte-macrophage colony-stimulating factor (Anti-GM-CSF) autoantibodies have been found to be associated with cryptococcosis in non-HIV individuals but this syndrome has never been described in Thai population.

Methods

We report here the case series of patients hospitalized in a tertiary care hospital in Northern Thailand.

Results

Three apparently immunocompetent patients, 34, 38, and 45 years old, were presented with neurological manifestations. Brain computed tomography scans and lumbar punctures were performed and the results showed evidence of cryptococcal meningoencephalitis. Two of the patients also had pulmonary cryptococcosis. We performed Anti-GM-CSF autoantibody ELISA assays in the patient's sera and all of three serum samples revealed a high titer of anti-GM-CSF autoantibodies. The patients were treated with amphotericin B deoxycholate with or without flucytosine for induction antifungal therapy, followed by fluconazole consolidation treatment. All patients were cured and had favorable outcomes.

Conclusions

Anti-GM-CSF autoantibodies syndrome is underrecognized in Thai patients and is a new entity of immunodeficiency associated with cryptococcal meningoencephalitis and disseminated cryptococcosis in Thai patients.
P501 Aspergillus fumigatus complicates one third of the patients with suspected bronchial asthma or pulmonary tuberculosis: Clinical validation of indigenously developed diagnostic kits
Authors: Kale Kavita , Bharmal Mohammed Husain , Choudhary Hansraj , Chowdhary Anuradha , Chaudhry Anil , Agarwal Ritesh , Shivaprakash M. Rudramurthy , Chakrabarti Arunaloke , Madan Taruna
Published: September 2022

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

 

Objectives

Aspergillus fumigatus, an opportunistic fungus, causes complications in about 5%-20% of bronchial asthma and about 26% of pulmonary tuberculosis patients. Detection of Aspergillus fumigatus specific IgG and IgE antibodies in the patient serum is an excellent tool to screen for Aspergillus sensitization early on to employ anti-fungal drugs in the clinical management to stall the progression of lung fibrosis.

Methods

Novel indigenous AfuPEPLISA assays were developed for the detection of specific IgG and IgE, based on the 12 amino acid long synthetic peptide epitope of Asp f1, an 18 kDa major allergen/antigen. The novel diagnostic kits were manufactured at a licensed GMP facility under a test license. Independent validation of the kits was pursued at PGIMER and VPCI hospitals in suspected bronchial asthma patients (n = 1307), and the diagnostic efficiency was compared with currently used ImmunoCAP assay.

Results

The diagnostic specificity and sensitivity were found to be 95.7% and 89.8%, respectively, for IgG; and 94.2% and 70%, respectively for IgE AfuPEPLISA, and were not significantly different from ImmunoCAP assay. Screening of the suspected patients of pulmonary tuberculosis (PTB) at RBIPMT Hospital for the presence of A. fumigatus specific IgG and IgE antibodies was pursued using AfuPEPLISA kits. A total of 82 out of 254 suspected PTB patients (32.3%) were seropositive in agreement with the previous reports.

See Figures 1 and 2 below.

Conclusion

The study inferred that indigenously developed AfuPEPLISA kits are an economically viable option to integrate in the clinical management of patients with suspected bronchial asthma or PTB for efficient diagnosis of Aspergillus sensitization.
P7 Banging your head against the (fungal) wall
Authors: Gow Neil A R
Published: September 2022

Plenary session 7, September 23, 2022, 2:00 PM - 3:00 PM

 

 

For a fungus, there may be nothing as biologically variable and highly regulated as its cell wall. This makes the wall intellectually and methodologically challenging to study, but worth the effort because they have the potential to reveal novel targets for antifungal drugs and the mechanisms that are important for immune recognition. Differences and adaptations to the cell wall composition can serve to resist chemotherapy and create a moving target for efficient immune recognition. We have used a variety of microscopic, forward, and reverse genetic and immunological tools to generate a new spatially accurate model of the cell wall and to explore how dynamic changes in the wall influence drug efficacy and immune surveillance. We show that the cell has a mechanism to maintain wall robustness within physiological limits. We also have demonstrated that immune-relevant epitopes can be diffuse or clustered, superficial or buried in the cell wall and they changed during batch culture and between yeast, hypha, and other cellular morphologies. We have screened libraries of mutants with immune pattern recognition receptors (PRRs) to define the sub-set of fungal genes that assemble and regulate immune epitopes. This is revealing novel processes that are important for the assembly of the cell wall. These experiments demonstrate that the fungal cell surface is ordered, complex and dynamically changing, requiring immune recognition to mobilize the concerted action of multiple receptors operating singly and in combination. My presentation will focus on work that demonstrates and describes recent advances that have generated a scaler and dynamic model of the cell wall that illuminates mechanisms of immune recognition and cell wall homeostasis.
S1.1d Risk factors associated with oropharyngeal candidiasis in COVID-19 patients: a case control study
Authors: Salehi Mohammadreza , Kiyaei Reyhaneh Sadat , Khodavaisy Sadegh , Khajavirad Nasim , Manshadi Seyed Ali Dehghan , Darazam Ilad Alavi , Seifi Arash
Published: September 2022

S1.1 Controversies in the clinical management of invasive candidiasis in critically ill patients, September 21, 2022, 11:00 AM - 12:30 PM

 

Objectives

With the emergence and spread of the coronavirus disease-19 (COVID-19) in the world, humans have been faced with the biggest challenge in health care systems in recent decades. The aim of the present study is to identify risk factors associated with oropharyngeal candidiasis (OPC) in COVID-19 patients.

Methods

The total number of confirmed COVID-19 patients was 218 (105 participants as cases who experienced OPC and 113 participants as controls without any evidence of OPC). The questionnaire used in this study consists of demography data, treatment strategy, clinical and laboratory data, and underlying diseases to collect information at the time of clinical OPC and follow them until the end of hospitalization.

Results

Pseudomembranous candidiasis (77/105, 73.3%) was the most prevalent form of OPC in case patients. The majority of cases (58.1%) and control (58.4%) groups were male. Increasing age of COVID-19 patients (P = .03) and length of hospitalization (P = .016) were significantly associated with OPC. Diabetes (P = .003), solid tumor (P = .019), and hypertension (P = .000) were the most common underlying conditions. Use of dentures (P = .003) and poor oral hygiene (P = .000) were related to OPC in case groups. Therapy with chloroquine (P = .012), IVIG (P = .001), diuretics (P = .000), and corticosteroid pulse therapy (P = .000) were significantly associated with the development of OPC in case patients.

Conclusion

It is reasonable to consider that old age, length of hospitalization, poor oral hygiene, corticosteroid usage, diabetes, solid tumor, and hypertension may predispose to the development of OPC in COVID-19 patients.
S4.5a A randomized, double blind phase II proof-of-concept superiority trial of fosravuconazole 200 mg or 300 mg weekly dose versus itraconazole 400 mg daily, all three arms in combination with surgery, in patients with eumycetoma in Sudan—top line results
Authors: Fahal Ahmed Hassan , Bakhiet Sahar Mubarak , Mohamed El Samani Wadaa , Ahmed Eiman Siddig , Bakhiet Osama El Hadi , Yousif Abu Bakar Ahmed , Fahal Lamis Ahmed , Alla Hadel Yassir Atta , Razig A Razig Osman A , Siddig Emmanuel Edwar , Hassan Omnia Babekir , Abdulla Sahar A Rahman , Mohaemd Amir Faroug , Jodda Nagwa Adam , Bahar Mustafa El Nour , Nyaoke Borna A. , Egondi Thaddaeus , Oyieko Peelen , Zijlstra Eduard E. , Strub-Wourgaft Nathalie
Published: September 2022

Objectives

To determine whether, in addition to surgery, fosravuconazole (Fos) monotherapy of either 200 mg or 300 mg weekly was more effective [defined as complete cure at the End of Treatment (EOT; 52-week) visit] than the standard-of-care 12-month regimen of itraconazole (Itra) monotherapy, in patients with small to moderate eumycetoma lesions caused by Madurella mycetomatis.

Methods

This was a single-center (Mycetoma Research Center, Khartoum, Sudan), comparative, randomized, double-blind, parallel-group, active-controlled, clinical superiority trial in participants with eumycetoma requiring surgery. Participants were randomized in a 1:1:1 ratio. In Arm 1 participants took a loading dose of Fos 300 mg on Day 1, Day 2, and Day 3, followed by a weekly dose of 300 mg for a total duration of 12 months. In Arm 2 participants took Fos 200 mg on Day 1, Day 2, and Day 3, followed by a weekly dose of 200 mg for a total duration of 12 months. In Arm 3 participants took Itra 400 mg daily for 12 months. All patients underwent surgery after 6 months of treatment in which the remaining lesion was removed. Mycetoma lesions were between 2 to ≤16 cm in diameter. The age cut-off was ≥15 years. The diagnosis of M. mycetomatis was confirmed by PCR. Safety monitoring included, among other, severe, and serious treatment-related events.

Results

A total of 122 participants were screened and 104 participants were enrolled (34 in Fos 300 mg, 34 in Fos 200 mg weekly, and 36 in Itra 400 mg). Complete cure after 12 months (EOT) of treatment was demonstrated in terms of an absence of eumycetoma mass, sinuses, and discharge; normal ultrasound of the lesion site or normal MRI; and a negative fungal culture from a surgical biopsy if a mycetoma mass was present. The complete cure rate was assessed in the mITT population. Secondary efficacy analyses were performed in the Per Protocol population. In addition, the influence of age, changes in clinical symptoms and signs, size, and duration of the lesion on outcome was examined. Safety was satisfactory and compliance was good.

Conclusion

This is the first randomized controlled trial in eumycetoma, comparing two azoles, fosravuconazole (two dosage regimens) and itraconazole, in combination with surgery. Detailed efficacy and safety results will be communicated and discussed in the oral presentation.