Mucor Research Articles

Inhibitory effect of lupeol, quercetin, and solasodine on Rhizopus oryzae: A molecular docking and dynamic simulation study

BackgroundMucormycosis is an infection caused by fungi belonging to the order Mucorales. Rhizopus oryzae is one of the most prevalent organisms identified in mucormycosis patients. Because it spreads quickly through the blood vessels, this opportunistic illness has an exceptionally high fatality rate, even when vigorous treatment is administered. Nonetheless, it has a high tolerance to antifungal medicines, limiting treatment options. As a result, improved methods for preventing and treating mucormycosis are desperately needed. Hence, this study was aimed at assessing the effect of lupeol, quercetin, and solasodine against mucormycosis based on computational approaches. MethodsThe Rhizopus oryzae RNA-dependent RNA polymerase (RdRp) was the target for the design of drugs against the deadly mucormycosis. The three-dimensional structure of the RdRp was modelled with a Swiss model and validated using PROCHECK, VERIFY 3D, and QMEAN. Using the Schrodinger maestro module, a molecular docking study was performed between RdRp and the antimicrobial phytochemicals lupeol, quercetin, and solasodine. A molecular dynamics (MD) simulation study was used to assess the stability and interaction of the RdRp with these phytochemicals. ResultsThe RdRp protein binds strongly to lupeol (−7.2 kcal/mol), quercetin (−9.1 kcal/mol), and solasodine (−9.6 kcal/mol), according to molecular docking assessment based on the lowest binding energy, confirmation, and bond interaction. Simulations suggest that lupeol, quercetin, and solasodine complexes with RdRp and showed stable confirmation with minimal fluctuation throughout the 200 nanoseconds based on the RMSD and RMSF trajectory assessments. ConclusionThe molecular docking and MD simulation investigation improved our understanding of phytochemical-RdRp interactions. Due to its high affinity for RdRp, solasodine may be a better treatment option for mucormycosis.

A Rapid and Specific Real-Time PCR Assay for the Detection of Clinically Relevant Mucorales Species

Infections triggered by filamentous fungi placed in the order Mucorales, phylum Zygomycota, can cause serious harm to immunocompromised patients. Since there is lack of a standardized PCR (polymerase chain reaction) assay for early diagnosis of this fungal infection, this work was aimed to develop a new PCR assay able to detect the presence of Mucorales genera in clinical specimens. Here, we describe a novel diagnostic TaqMan MGB probe assay for precise and rapid detection of the most common clinical species of Mucorales. Zygomycete-specific oligonucleotides were designed to specifically amplify and bind highly conserved sequences of fungal 28S rRNA gene. Additionally, we succeeded in differentiating Mucorales species (i.e., Rhizopus, Lichtheimia, Mucor, and Rhizomucor) in artificially infected serum samples, suggesting that the quantitative capability of this real-time PCR assay could potentially optimize the diagnosis of mucormycosis.

Post-Coronavirus Disease Mucormycosis: Predisposing Factors and Possible Treatment: A Narrative Review

Absract: Mucormycosis, commonly known as black fungus, is a life-threatening fungal infection belonging to the order Mucorales. It affects individuals having an impaired immune response or immune disorders such as diabetes mellitus, induced immunosuppression, hematological cancers, acquired immune deficiency syndrome, or who have gone through organ transplantation. Black fungus had symptoms like difficulty in breathing, blurred vision, coughing out blood, chest pain, blackening over the area of the nose. Tissue necrosis is the main symptom of this infection. It was increasing day by day and seen in vulnerable patients, including patients which were suffering from COVID 19 (coronavirus) and who were recovered. As we had seen that black fungus cases were rising in recovered COVID patients, various cases of white and yellow fungus were also reported.The treatment approach includes the use of antifungal agents, triazoles, surgery, combination therapy, etc. This review describes the clinical manifestation, predisposing factors, and treatment strategy of mucormycosis.

Molecular diagnosis of rhino-orbital mucormycosis in a COVID-19 setting.

Mucormycosis is a severe fungal infection caused by species of the order Mucorales. Early and accurate diagnosis is a prerequisite in the management of the disease. In the present study, we evaluated and compared two PCR-based techniques for the diagnosis and identification of mucormycosis in patients with rhino-orbital mucormycosis (ROM) post-COVID-19. Diagnosed clinically and radiologically, 25 patients of ROM were included in the study and endoscopically or blind collected nasal swabs or orbital tissues were submitted for microbiological evaluation (direct microscopy + culture) and PCR using primers targeting two different loci (ITS and 28S rDNA region) for diagnosis. All PCR products were further processed for species identification using Sanger sequencing whenever possible. Of the 25 samples included in the study, 16 samples were positive for presence of fungal filaments by Smear suggestive of Mucorales sp., but only 7/25 grew in culture. ITS-based PCR was able to identify mucormycosis in 7/25 (28%) samples and 28S rDNA PCR showed positivity for 19/25 (76%) samples. Rhizopus oryzaewas found to be the predominant species in our study. The sensitivity and specificity of 28S rDNA PCR compared to culture were found to be 85.71% and 27.78%, respectively, while for ITS-based PCR, they were 42.86% and 77.78%, respectively. 28S rDNA-based PCR is a reliable and sensitive method for early diagnosis of mucormycosis. Molecular techniques have shown a promising future to provide quick and effective treatment by accurately identifying the aetiologic agent.

Clinical case of rhino-orbital mucormycosis in a convalescent COVID-19 patient: diagnostic and treatment tactics

According to current data, SARS-CoV-2 virus has the ability to cause multi-organ pathology, leading to acute damage of various organs and systems and long-term consequences characterized by polymorphic symptoms. Recently, a high incidence of invasive mycoses, particularly mucormycosis COVID-M, has been noted among the COVID-19 complications. The predisposing factor for the development of this pathology is diabetes mellitus, immunodeficiency states, and prolonged use of high doses of glucocorticosteroids. Mucormycosis is characterized by severe clinical manifestations and high lethality, and timely diagnostics of this pathology often represents a difficult problem. The aim of this study was to analyze a clinical case of rhino-orbital mucormycosis in convalescent COVID-19 patient. In the study, there was used mucopurulent nasal discharge from the patient previously hospitalized with a severe novel coronavirus infection. Here, we describe the methodology allowing to isolate and identify a pure mold fungus culture from the biomaterial using methods of routine bacteriology and MALDI-ToF mass spectrometry. Direct microscopy examination of nasal cavity discharge revealed branched non-septic hyphae with a characteristic branching angle, allowing to preliminarily diagnose invasive mucormycosis. Growth of mycelial fungus colony was observed by using Sabourauds medium with potassium tellurite. Microscopy of the pure culture revealed branching mycelium without septa, broad, with irregular thickness, unsegregated hyphae, and sporangia with a typical column specific to mucormycetes. Analysis of the obtained mass spectra allowed to establish the microbial species identity as Lichtheimia corymbifera. The latter along with other members of the order Mucorales, are known to cause mucormycosis. As a result of antifungal treatment (Amphotericin B) and timely surgical intervention, the patient was discharged from the hospital with prominent clinical improvement and no complaints during further outpatient follow-up period. The analysis of this clinical case showed the lack of alertness in some clinical diagnostic laboratories to detect pathogens of invasive mycoses. To avoid errors, while making a diagnosis, attention should be paid not only to detection of fungal spores in clinical material, but also take into account the structure of mycelium underlying major difference between yeast-like fungi, higher and lower molds. The isolation and identification of a pure pathogen culture allows to confidently verify the diagnosis, timely correct the treatment tactics and monitor circulation of mycotic agents to prevent occurrence of mycoses in most vulnerable patients cohorts.

Emerging Syndemic: Black Fungus–A Post-COVID-19 Mucormycosis

Novel coronavirus has created a havoc in India; about 30 million cases have been reported and 0.4 million deaths are recorded till now due to coronavirus disease 2019 (COVID-19). But nowadays, some patients of COVID-19 in India are battling a very rare but fatal disease, that is, mucormycosis or “black fungus” disease. The consciousness about the black fungus disease in many people of India is due to its rising cases of COVID-19-associated mucormycosis (CAM) mostly among the people who have recovered from COVID-19. Following recovery from COVID-19, thousands of cases of several complications of patients regarding CAM are reported especially during the second wave of COVID-19 in India. Mucormycosis or “black fungus” is a rare disease caused by fungi belonging to the order Mucorales. It is a disease observed following infection with the novel coronavirus in India and has already taken the form of a pandemic in many states.[1] [2] Therefore, scientists have chosen to name the disease as a syndemic since this is synergistically created with the pandemic. The ubiquitous molds of mucormycosis having a worldwide dispersal, including the Rhizopus, Apophysomyces, Mucor, and Lichtheimia species, are found in plants, soil, decaying fruits and vegetables, and even in air. If contact occurs with airborne spore, then it germinates into hyphae and is regarded a very rare occurrence. This preferentially takes place inside the bucconasal cavity. After germination, it can invade the neighboring tissue and blood vessels that results in characteristic hemorrhage followed by black color development. The visualization of these dark necrotic tissues on skin and blood vessels of the affected person is termed as black fungus disease. Till now five major forms of mucormycosis have been identified, for example, rhinocerebral (44–49%), cutaneous (10–16%), pulmonary (10–11%), disseminated (6–11.6%), and gastrointestinal (2–11%) forms. Among these, the most common rhinocerebral form usually occurs in immunocompromised individuals. It exhibited a “pattern paranasal infection” with a porch into the oral cavity often. It is a quickly emerging angioinvasive infection, with rhinoorbital-cerebral and pulmonary manifestations. According to the Indian government, there are over 11,700 reported cases and over 126 casualties as of May 2021.[3] There is a surge in terms of infection rates. Though mucormycosis is generally regarded as harmless to an immunocompetent host, it may be fatal in some cases in its combination form with factors like indiscriminate use of steroids or other immunosuppressants, even in subjects presenting with mild symptoms of COVID-19. Immunocompromised patients like people with hematological malignancies, damaged mucosal layer, uncontrolled diabetes, ketoacidosis, and viral induced lymphopenia are the prime victims of this deadly fungus.[4] It is a fatal disease if unnoticed as it is invasive to blood vessels, distant organs, nose, mouth, eyes, sinus, and even brain. If untreated, the infection usually develops speedily, and leads to death within a few days of contamination.

60-Year-Old Patient with Invasive Mold Infection Consequent to an Encounter with a Barnyard Animal

Abstract Introduction/Objective Lichtheimia and Scedosporium species are ubiquitous fungi associated with a range of clinical presentations. We report a complex soft tissue coinfection caused by Lichtheimia spp. and Scedosporium spp. following a puncture wound by a rooster spur. Methods/Case Report A 60-year-old immunosuppressed man with a history of heart transplant presented with a non-healing wound 2-months after sustaining a lower leg puncture secondary to a rooster spur. The patient was previously treated with Augmentin for presumed cellulitis without improvement. To characterize the ongoing disease process, the wound was sampled with tissue portions routed for both histopathologic review and culture. In short order, the biopsy demonstrated invasive hyaline pauciseptate fungal hyphae consistent with organisms of the Mucorales order. In congruence, culture rapidly revealed a mucoraceous mold, subsequently identified as a Lichtheimia spp. Thus, the patient was treated with liposomal amphotericin B. However, days later, a second fungus - a Scedosporium spp. - was isolated from the original specimen. Consequently, isavuconazonium sulfate therapy was added. Re-review of the initial biopsy enabled distinction of two populations of fungal hyphae plausibly representing both molds. Despite numerous debridements and optimal medical management, the patient was ultimately referred for amputation. Results (if a Case Study enter NA) NA. Conclusion When encountered in an immunocompromised host, providers understandably respond to an invasive mucoraceous mold with alarm followed by quick, decisive action. However, septate molds, such as the Scedosporium spp., can also be aggressive. Further, the presence of more than one invasive mold presents a treatment challenge as the mucormycetes may require surgery coupled with amphotericin B therapy; whereas, the a Scedosporium spp. may be wholly resistant to amphotericin B. This case illustrates the critical role that an alert pathologist plays in guiding management through integration of data from different diagnostic modalities. It also constitutes an emphatic reminder that an illness may be caused by more than one actionable, invasive fungus.

Mucormycosis in India: Pathophysiology and Perspectives on Treatment and Management.

Mucormycosis, also known as "black fungus," is a potentially fatal disorder that causes blurred or double vision, chest pain, and breathing problems. The introduction of novel risk factors and causative agents, as well as the problems with controlling the disease, are all significant problems with mucormycosis in India. It is most common among COVID-19 patients. Mucormycosis is an invasive fungal disease that primarily affects immunosuppressant patients, mainly caused by mold fungi of the genus mucor, rhizopus, rhizomucor, and absidia, which are in the zygomycetes class and the Mucorales order. The most common risk factor is diabetes mellitus, followed by haematological malignancy and solid-organ transplantation. Reversal of underlying predisposing factors, surgical debridement of infected tissues, and proper antifungal therapy are all required for the treatment of mucormycosis. In this review, the epidemiology, pathogenesis, and symptoms of black fungus and its association with covid-19, treatment, and diagnosis are discussed.

Metabarcoding assessment of fungal diversity in brown algae and sponges of Mauritius.

Marine fungi are largely associated with second most inhabitants of the marine ecosystem such as sponges and algae. They are important colonizers and play vital ecological roles, such as nutrient cycling, organic matter decomposition, and symbiosis with other organisms. High throughput sequencing methods have been used successfully to reveal unknown fungal communities associated with a number of hosts particularly in the marine environment. However, the diversity of marine fungi associated with sponges and brown algae in Mauritius remains largely unknown. Traditional methods based on culturing do not provide reliable estimate of fungal diversity as only those that are able to grow under laboratory conditions are dominant; in addition, a large proportion of fungi, cultured in vitro remain most of the time unidentifiable, given that there are no sporulating structures to be examined morphologically. To overcome these limitations, we employed Illumina sequencing to unravel fungi species present in the sponges, Iotrochota sp. and Biemna sp. and the brown algae Turbinaria conoides, Sargassum pfeifferae, and Sargassum obovatum, collected from the north of Mauritius. Diversity analyses revealed that Biemna sp. had the highest diversity from the sampled sponges with fungi from 24 orders being recovered while from brown algae; Turbinaria conoides had the highest diversity with recovery of fungal taxa of the orders Botryosphaeriales, Chaetothyriales, Eurotiales, Hypocreales, and Mucorales with the latter four orders being common in both sampled algae and sponges. Beta diversity analyses revealed clustering only in the algae, Turbinaria conoides, and Sargassum pfeifferae and not in the co-occurring sponges, indicating that sampling location did not have much influence on fungal diversity. Our findings provide the first amplicon sequencing based insights of the fungal communities associated with macro-algae and sponges in Mauritius and supplements research on the fungal community existing in the oceans around the world.

Ibrexafungerp, a Novel Triterpenoid Antifungal in Development for the Treatment of Mold Infections.

Molds are ubiquitous in the environment, and immunocompromised patients are at substantial risk of morbidity and mortality due to their underlying disease and the resistance of pathogenic molds to currently recommended antifungal therapies. This combination of weakened-host defense, with limited antifungal treatment options, and the opportunism of environmental molds renders patients at risk and especially vulnerable to invasive mold infections such as Aspergillus and members of the Order Mucorales. Currently, available antifungal drugs such as azoles and echinocandins, as well as combinations of the same, offer some degree of efficacy in the prevention and treatment of invasive mold infections, but their use is often limited by drug resistance mechanisms, toxicity, drug-drug interactions, and the relative paucity of oral treatment options. Clearly, there is a need for agents that are of a new class that provides adequate tissue penetration, can be administered orally, and have broad-spectrum efficacy against fungal infections, including those caused by invasive mold organisms. Ibrexafungerp, an orally bioavailable glucan synthase inhibitor, is the first in a new class of triterpenoid antifungals and shares a similar target to the well-established echinocandins. Ibrexafungerp has a very favorable pharmacokinetic profile for the treatment of fungal infections with excellent tissue penetration in organs targeted by molds, such as the lungs, liver, and skin. Ibrexafungerp has demonstrated in vitro activity against Aspergillus spp. as well as efficacy in animal models of invasive aspergillosis and mucormycosis. Furthermore, ibrexafungerp is approved for use in the USA for the treatment of women with vulvovaginal candidiasis. Ibrexafungerp is currently being evaluated in clinical trials as monotherapy or in combination with other antifungals for treating invasive fungal infections caused by yeasts and molds. Thus, ibrexafungerp offers promise as a new addition to the clinician's armamentarium against these difficult-to-treat infections.

Molecular Mechanisms of Antifungal Resistance in Mucormycosis.

Mucormycosis is one among the life-threatening fungal infections with high morbidity and mortality. It is an uncommon and rare infection targeting people with altered immunity. This lethal infection induced by fungi belonging to the Mucorales family is very progressive in nature. The incidence has increased in recent decades owing to the rise in immunocompromised patients. Disease management involves a multimodal strategy including early administration of drugs and surgical removal of infected tissues. Among the antifungals, azoles and amphotericin B remain the gold standard drugs of choice for initial treatment. The order Mucorales are developing a high level of resistance to the available systemic antifungal drugs, and the efficacy still remains below par. Deciphering the molecular mechanisms behind the antifungal resistance in Mucormycosis would add vital information to our available antifungal armamentarium and design novel therapies. Therefore, in this review, we have discussed the mechanisms behind Mucormycosis antifungal resistance. Moreover, this review also highlights the basic mechanisms of action of antifungal drugs and the resistance landscape which is expected to augment future treatment strategies.

Current treatments against mucormycosis and future directions.

Mucormycosis (previously called zygomycosis) is a serious but rare fungal infection caused by a group of fungi belonging to the order Mucorales. These molds exist throughout the environment and generally do not cause serious problems in humans. Mucormycosis mainly affects individuals who are immunocompromised. The clinical manifestations of mucormycosis are wide-ranging; they include sinusitis (pansinusitis, rhino-orbital, or rhino-cerebral) as well as cutaneous, gastrointestinal, pulmonary, and disseminate infections. Many uncertainties remain regarding how to control these infections despite the recent addition of triazoles to the antifungal arsenal for treating this infection. Currently, lipid formulations of amphotericin B have become the standard treatment for mucormycosis due to their efficiency. Moreover, a growing body of data supports the need for surgical excision of infected and/or necrosed tissue whenever practical. In this mini review, the current status of treatment options for mucormycosis and recent studies of novel therapeutic options will be presented.

The TLR-NF-kB axis contributes to the monocytic inflammatory response against a virulent strain of Lichtheimia corymbifera, a causative agent of invasive mucormycosis.

Invasive mucormycosis (IM) is a life-threatening infection caused by the fungal order Mucorales, its diagnosis is often delayed, and mortality rates range from 40-80% due to its rapid progression. Individuals suffering from hematological malignancies, diabetes mellitus, organ transplantations, and most recently COVID-19 are particularly susceptible to infection by Mucorales. Given the increase in the occurrence of these diseases, mucormycosis has emerged as one of the most common fungal infections in the last years. However, little is known about the host immune response to Mucorales. Therefore, we characterized the interaction among L. corymbifera—one of the most common causative agents of IM—and human monocytes, which are specialized phagocytes that play an instrumental role in the modulation of the inflammatory response against several pathogenic fungi. This study covered four relevant aspects of the host-pathogen interaction: i) The recognition of L. corymbifera by human monocytes. ii) The intracellular fate of L. corymbifera. iii) The inflammatory response by human monocytes against the most common causative agents of mucormycosis. iv) The main activated Pattern-Recognition Receptors (PRRs) inflammatory signaling cascades in response to L. corymbifera. Here, we demonstrate that L. corymbifera exhibits resistance to intracellular killing over 24 hours, does not germinate, and inflicts minimal damage to the host cell. Nonetheless, viable fungal spores of L. corymbifera induced early production of the pro-inflammatory cytokine IL-1β, and late release of TNF-α and IL-6 by human monocytes. Moreover, we revealed that IL-1β production predominantly depends on Toll-like receptors (TLRs) priming, especially via TLR4, while TNF-α is secreted via C-type lectin receptors (CTLs), and IL-6 is produced by synergistic activation of TLRs and CTLs. All these signaling pathways lead to the activation of NF-kB, a transcription factor that not only regulates the inflammatory response but also the apoptotic fate of monocytes during infection with L. corymbifera. Collectively, our findings provide new insights into the host-pathogen interactions, which may serve for future therapies to enhance the host inflammatory response to L. corymbifera.

P396 Utility of nasal swabs as samples for the diagnosis of Mucormycosis using molecular methods for detection

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM ObjectivesMucormycosis is an aggressive, life-threatening infection caused by fungi in the order Mucorales. There was an explosion of new cases of rhino-sino-orbital mucormycosis following the COVID pandemic in India, and the need for easy and rapid diagnostics was felt. The current diagnosis of mucormycosis relies on mycological cultures, radiology, and histopathology. These methods lack sensitivity and are most definitive later in the course of infection, resulting in the failure of timely intervention.A real-time multiplex PCR platform is commercially available for the detection of Rhizopus spp., Mucor spp. Rhizomucor spp., Lichtheimia spp., and Cunninghamella spp. (PN-700, MucorGenius®, PathoNostics®, Maastricht, The Netherlands) This real-time PCR has been validated to identify these fungal pathogens from bronchoalveolar lavage, tissue, and serum samples. This study aimed to validate this PCR-based system to detect Mucorales from nasal swab samples and evaluate its utility in the detection of Mucorales from nasal cavities of high-risk patients developing signs and symptoms of mucormycosis.MethodsA single-center cross-sectional observational study was conducted on 50 hospitalized adult patients with signs and symptoms of mucormycosis. Nasal swabs were taken for PCR analysis once there was a clinical suspicion and were compared with the results of the gold standard. The gold standard for the diagnosis of mucormycosis was the conventional method (KOH mounted microscopy/HPE). Demographic details and risk factors for these patients were recorded, and the RTPCR-based test was run on the nasal swab samples of all these 50 patients. The workflow is depicted graphically in Fig. 1 (Created with BioRender.com).ResultsThe study population mean (SD) age was 50 (16) years and consisted of 32 (64%) males. A total of 39 (78%) patients were known cases of diabetes mellitus, 48 (96%) patients had amphotericin B intake, and 20 (40%) had posaconazole intake. In all, 21 (42%) patients had a past history of COVID-19 infection; 14 patients had received steroids and 10 patients received oxygen support. PCR for Mucorales was positive in 15 (30%) patients while the KOH mount was positive in 4 (8%) patients.ConclusionThese results are not encouraging for the use of nasal swabs as the sample for diagnosis of mucormycosis. Though the PCR performed better on the swab samples than KOH preparation and culture techniques, it highlights the importance of using standard sampling methods.

P365 Upsurge of Mucormycosis in COVID-19—a retrospective study in a tertiary care hospital in Punjab

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM ObjectivesCoronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been linked to a variety of opportunistic bacterial and fungal infections. Mucorales have been reported as the main fungal pathogens to exist as co-infection with COVID-19. Factors that contribute to a higher incidence of Mucormycosis or Mucorales to germinate in COVID-19 patients are high glucose levels in their blood (diabetes, steroid-induced hyperglycemia), low oxygen content (hypoxia), high iron levels, and decreased phagocytic activity of neutrophils due to immunosuppression because of cytokine storm in SARS-CoV-2 infection. Mucormycosis is an angioinvasive disease caused by order Mucorales and genus Rhizopus, Mucor, Rhizomucor, Cunnighamella, and Lichthemia. The most common species amongst all is Rhizopus arrhizus which is responsible for 90% cases of Rhino-Orbital Cerebral form and accounts for 60% cases of mucormycosis cases in India.MethodsA retrospective study was conducted at Christian Medical College and Hospital, Ludhiana from May 1, 2021 to February 28, 2022 for a duration of 10 months. Most of the samples obtained were necrotic bone/tissue or mucosa from the rhino-cerebral part. The obtained sample was inoculated on Sabouraud's Dextrose Agar (SDA) at 22°C as well as 37°C followed by 40% KOH examination. The tubes were routinely checked once in a week and Lactophenol Cotton Blue (LPCB) preparation was made from teasing the isolate once it becomes culture positive.ResultsTotal 29 samples were smear-positive for broad, sparsely septate hyphae in KOH examination under the microscope. Out of those 29 cases, 18 (62.06%) patients were COVID-19 positive (either RTPCR positive, TrueNat PCR positive, or Rapid Antigen positive), 5 patients were COVID-19 negative and COVID-19 testing was not done in 6 patients. Out of 29 smear-positive cases, 17 (58.62%) were culture positive for Mucorales, 7 (24.13%) grew contaminants namely Aspergillus species (mainly Aspergillus flavus), Penicillium species, bacterial contamination, and 5 (17.24%) were culture negative. Amongst 17 cases of Mucorales, 9 (52.94%) were Rhizopus species, 6 (35.29%) were Mucor species and 2 (11.76%) were Rhizomucor species. Amongst the culture-positive cases for Mucorales, 13 (72.22%) cases were COVID-19 positive.ConclusionCOVID-19 has thrown the entire globe into chaos, and there is still no specific cure for this viral illness. Patients are susceptible to secondary fungal infections such as Mucormycosis as a result of the infection, immunosuppression, previous comorbidities, and medicines. Mucormycosis infection is severe because of its rapid disease progression and angioinvasive nature. As a result, researchers and healthcare practitioners should take immediate steps to control this mucormycosis infection by understanding its impact and severity, particularly in COVID-19 patients. A multidisciplinary approach should involve quick diagnosis, antifungal therapy, any surgical consultation, and treatment that may help to reverse the underlying disease.

P366 Role of the Sit1 siderophore transporter in iron uptake, germination, and virulence of Mucor lusitanicus

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

P303 An unusual case of isolated gluteal abscess

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PMBackgroundMucormycosis is an invasive infection caused by fungi belonging to the order Mucorales. The angioinvasive disease caused by these fungi can prove to be fatal despite appropriate treatment. We report an unusual case of a gluteal abscess caused by a probable mucormycosis in an apparently immunocompetent individual.Case DescriptionA 68-year-old gentleman hailing from a rural area of Bihar, India presented with a painful swelling over the left buttock region for 4 weeks. He was a known hypertensive and had ischemic heart disease. He denied any history of fever. The lump had gradually increased in size. He was a retired school teacher with a farmland and reared livestock at home. He was a non-vegetarian and denied any addictions. He had a history of intermittent lower backache for which he used to take occasional intramuscular analgesic injections over his buttocks from a local medical practitioner.On examination, the swelling was about 4 cm X 4 cm in size, fluctuant, with ill-defined margins over the lateral region of the left buttock. The swelling was tender, warm, and not fixed to underlying structures. Systemic examination was unremarkable. Ultrasound examination revealed an ∼7.2 × 4.2 × 7.8 cm cystic lesion with a volume of 126cC. It was located predominantly in subcutaneous fat extending into muscular plane with septa and solid components in the left gluteal region (Fig. 1). It had thick walls and fine internal echoes within. Other investigations were unremarkable except for glycosylated Hb, which was 6.2%. Incision and drainage were done.During the procedure, it was seen as a cyst with a thick wall that was removed in toto. The contents were explored after removal and were found to be yellowish black with mucoid consistency. Histopathological examination revealed numerous broad, ribbon-like, aseptate fungal hyphae with right-angled branching infiltrating the inflamed tissue (Fig.2). There were numerous epithelioid granulomas surrounding the fungal elements in the soft tissue of the wall. The findings were consistent with a fungal abscess caused by mucormycosis. Culture of the fluid/pus was negative. Thus, a diagnosis of mucormycotic gluteal abscess was made and patient was commenced on 50 mg of amphotericin B deoxycholate in view of financial restraints. High resolution computed tomography of chest was done which was unremarkable.He developed an acute kidney injury after 2 doses of amphotericin B deoxycholate which was then stopped. Oral posaconazole was started. He has developed bilateral leg swelling post-oral posaconazole and is commenced on oral spironolactone for the same. The postoperative wound has healed well and there is no new swelling or tenderness over the area. He is planned for further follow-up.ConclusionsIsolated gluteal abscess caused by mucormycosis is rare in an apparently immunocompetent host.We assume that repeated intramuscular injections might have caused traumatic inoculation of fungus into the host which led to this outcome.

S4.1d In vitro activity of eight antifungals against 3343 filamentous pathogenic fungi collected during 18 years at the French National Reference Center for invasive mycosis and antifungals

S4.1 Treatment of rare mold infections in 2021: the role of new and old antifungals, September 22, 2022, 10:30 AM - 12:00 PM Background & ObjectivesThe NRCMA oversees the surveillance of invasive fungal diseases in France. As part of our expertise, we perform antifungal susceptibility testing based on European Committee on Antimicrobial Susceptibility Testing (EUCAST) methodology on all isolates. The antifungal profiles help us monitor the emergence of resistant isolates, determine the susceptibility pattern of wild-type strains to new antifungals, and in specific cases, determine the relationship between clinical failure and selection/emergence of a less susceptible isolate.We review the Minimum inhibitory concentrations (MIC) distribution of eight antifungals on clinical isolates of filamentous fungi identified at the NRCMA from 2003 to 2021.MethodsSpecies identification was performed by a combination of morphological features and multilocus sequencing. Only strains that produced enough conidia or spores were tested. In vitro susceptibility testing was performed according to the EUCAST procedure. Eight antifungal agents were used: triazoles [itraconazole, voriconazole, posaconazole, isavuconazole (since 2015)], echinocandins (caspofungin, micafungin), amphothericin B, and terbinafine. The concentrations inhibiting 50% (MIC50) and 90% (MIC90) of the isolates were determined for species with at least 5 and 10 isolates, respectively. For Aspergillus fumigatus isolates exhibiting high azole MICs, we sequenced the cyp51A gene for mutation screening.ResultsMICs were obtained for 3343 pathogenic strains. We identified Aspergillus spp. including cryptic species (32%), Fusarium spp. (21%), Mucorales (18%), phaeohyphomycetes (10%), i.e., Alternaria spp., Curvularia spp., Fonsecaea, Exophiala, Phaeoacremonium, rare hyphomycetes (9%), i.e., Rasamsonia, Paecilomyces, Trichoderma, Scopulariopsis. Scedosporium spp. (7%) and emergent pathogens such as Nannizziopsis obscura (1%), dimorphic fungi (1%), or to a less extent basidiomycetous molds. Examples of MIC results are presented in Table 1.For the nine genera of the order Mucorales, amphotericin B (AmB) exhibited low MICs except for Cunninghamella species and Saksenaea vasiformis. Posaconazole had variable activity depending on the species (high MIC values were observed for Mucor species) while voriconazole and echinocandins had none.In section Fumigati, amphotericin B MIC values were high due to the intrinsic resistance of cryptic species Aspergillus lentulus and A. udagawae. Other cryptic species were identified such as A. hiratsukae isolates which exhibited low MICs to all antifungals.Members of Aspergillus section Nidulantes such as A. nidulans and A. quadrilineatus showed variable MICs to caspofungin and amphotericin B.Among melanized fungi, Alternaria infectoria and A. alternata species group displayed low MICs of all azoles with the exception of voriconazole.Four Exophiala species were analyzed and had similar azole MICs, E. spinifera being the species with the lowest values.Multi-drug resistant profiles were observed especially in species belonging to Microascales such as Lomentospora prolificans, Microascus cirrosus, and Scopulariopsis brevicaulis. Members of Fusarium species complexes had predictably high MIC values to all antifungals including isavuconazole. Only Fusarium dimerum species complex had low MICs to amphotericin B.Further distribution analysis is ongoing. These large datasets provide a baseline for monitoring the emergence of antifungal resistance in our country and supports the fact that MIC determination should be performed for rare/emergent species and also in case of infections due to cryptic species, which would benefit patient management.

Post-COVID-19 sino-orbital mucormycosis: a case report

Mucormycosis is an invasive fungal infection caused by fungi of the order Mucorales. Mucorales fungi are ubiquitous in environment in association with decaying organic matter. Here we report the case of a 68-year old female who presented with history of ptosis of the left eye with decreased vision, facial pain and loss of sensation in the left cheek. She had history of COVID-19 infection. Magnetic resonances imaging of the brain revealed intense enhancement of left optic nerve. Bilateral spenoidal, ethmoidal and left maxillary sinus showed mucosal thickening. Histopathological and microbiological examination of the specimen confirmed the case of invasive mucormycosis. Despite treatment, patient died at 7th day of hospitalization.

P277 The epidemiology, clinical manifestations and outcomes of cerebral mucormycosis: A systematic review

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PMObjectivesMucormycosis is a devastating infection caused by Mucorales order ubiquitously existing in the environment. Cerebral mucormycosis, the mortal manifested type of brain infection, is commonly seen in association with deep immunocompromised status. Despite lethality of brain mucormycosis, the lack of consensus data specifically concerning clinical manifestations, radiographical characteristics, diagnosis methods, and management are severely felt.MethodsIn this systematic review and meta-analysis, we searched PubMed and Scopus (up to December 31, 2018) using the combination of the following keywords: (‘Mucor*’ or ‘Zygomyc*’) and (‘cereb*’ or ‘brain’ or ‘central nervous system’ or ‘intracranial’) and found ∼1462 articles.Only published case reports or case series with the definition of cerebral mucormycosis (finding the signs of this invasive mold in histopathological section or mycological examination and the presence of histopathological or radiological signs of brain involvement) were included. However, animal mucormycosis and papers in languages other than English or duplicates were excluded. Overall, 287/1462 articles were reviewed and included consisting of 345 cases of cerebral mucormycosis.ResultsA total of 206 (59.7%) patients were male. The most common risk factor was diabetes mellitus (51%), followed by hematological malignancies (23.8%). Remarkably, among hematological malignancies, acute lymphoblastic leukemia was significantly associated with cerebral mucormycosis (P <.001). In terms of reported risk factors, only 16.3% of patients had hematological malignancies till 2000, while the percentage of cases (29.7%) with this risk factor increased significantly after 2000 (P = .04). The most common clinical symptoms were orbital (46.4%) and neurological symptoms (41.2%), while headache was present in 35.9% of patients and fever only in 0.6%. Of the patients reported, 60.6% died and there was a significant correlation between mortality rate and diabetes mellitus (P = .003), while the mortality rate was not associated with other risk factors such as hematological malignancies.Conclusions: In patients with mucormycosis, the presence of orbital clinical symptoms may suggest cerebral involvement as much as the presence of neurologic symptoms. Finally, it can be said that Cerebral Mucormycosis is a very fatal mold infection, especially if it occurs in diabetic patients.