Medical mycology最新文献

The emergence of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), triggered a global pandemic. Concurrently, reports of mucormycosis cases surged, particularly during the second wave in India. This study aims to investigate mortality factors in COVID-19-associated mucormycosis (CAM) cases, exploring clinical, demographic, and therapeutic variables across mostly Asian and partly African countries. A retrospective, cross-sectional analysis of CAM patients from 22 medical centers across eight countries was conducted, focusing on the first 3 months post-COVID-19 diagnosis. Data collected through the ID-IRI included demographics, comorbidities, treatments, and outcomes. A total of 162 CAM patients were included. The mean age was 54.29 ± 13.04 years, with 54% male. Diabetes mellitus (85%) was prevalent, and 91% had rhino-orbital-cerebral mucormycosis. Surgical debridement was performed in 84% of the cases. Mortality was 39%, with advanced age (hazard ratio [HR] = 1.06, [P < .001]), rituximab use (HR = 21.2, P = .05), and diabetic ketoacidosis (HR = 3.58, P = .009) identified as risk factors. The mortality risk increases by approximately 5.6% for each additional year of age. Surgical debridement based on organ involvement correlated with higher survival (HR = 8.81, P < .001). The utilization of rituximab and diabetic ketoacidosis, along with advancing age, has been associated with an increased risk of mortality in CAM patients. A combination of antifungal treatment and surgical intervention has demonstrated a substantial improvement in survival outcomes.

Candida lusitaniae fungemia is a serious infection that is rarely reported in children. The aim of this study is to describe a case series of C. lusitaniae fungemia and review previous publications regarding this rare pathogen. This is a multicenter case series of children diagnosed with C. lusitaniae fungemia. A total of 18 cases that occurred over a 15-year period in five tertiary hospitals were included. Additionally, a review of the literature regarding C. lusitaniae fungemia in children was performed. A total of 18 cases were enrolled; 11/18 (61%) were males, with a mean age of 2.3 years. All patients had severe underlying diseases and risk factors for opportunistic infection, most commonly prematurity and malignancies. More than one-third of cases occurred during the last 2 years of the study period. All isolates were susceptible to all tested antifungals. The survival rate following the acute infection was 94%, whereas the survival rate of 14 previously published cases was 71%, with the most common underlying diseases being CGD and malignancies. Candida lusitaniae fungemia is not a common event in the pediatric population, occurring exclusively in children with severe underlying diseases and significant risk factors. This cohort revealed better clinical outcomes than previously reported. All tested isolates were susceptible to all antifungal agents; variability in susceptibility as previously reported was not found in this study. The allegedly higher rate of infection in recent years is in need of further investigation in larger prospective studies in order to conclude if a real trend is at play.

The second international meeting on endemic mycoses of the Americas (IMEMA) and the first international symposium on implantation mycoses (ISIM) took place in Santiago del Estero, Argentina, on September 25-27, 2023. The conference provided a platform for researchers, clinicians, and experts to discuss the latest developments in the field of endemic and implantation mycoses. Topics included epidemiology, diagnostic advances, treatment strategies, and the impact of environmental factors on the spread of these fungal diseases. IMEMA and ISIM contributed to the regional discourse on the mycoses, emphasizing the importance of international cooperation in addressing these public health challenges.

The increasing prevalence of Candida parapsilosis as a causative agent of fungal infections underscores the need to comprehensively understand its virulence factors. Secreted aspartic proteases (Saps) play a significant role in adhesion events, promoting biofilm formation, causing tissue damage and evading the host's immune response. In C. parapsilosis, three Saps have been identified: Sapp1, Sapp2 and Sapp3. The present study investigates the production dynamics of Sapp1 and Sapp2 across 10 clinical isolates of C. parapsilosis using various approaches. Each fungal isolate demonstrated the capability to utilize bovine serum albumin (BSA) as the sole nitrogen source, as evidenced by its degradation in a cell-free culture medium, forming low molecular mass polypeptides. Interestingly, the degradation of different proteinaceous substrates, such as BSA, human serum albumin (HSA), gelatin and hemoglobin, was typically isolate-dependent. Notably, higher proteolysis of HSA compared to BSA, gelatin and hemoglobin was observed. A quantitative assay revealed that the cleavage of a peptide fluorogenic substrate (cathepsin D) was isolate-specific, ranging from 44.15 to 270.61 fluorescence arbitrary units (FAU), with a mean proteolysis of 150.7 FAU. The presence of both Sapp1 and Sapp2 antigens on the cell surface of these fungal isolates was confirmed through immunological detection employing specific anti-Sapp1 and anti-Sapp2 antibodies. The surface levels of Sapp1 were consistently higher, up to fourfold, compared to Sapp2. Similarly, higher levels of Sapp1 than Sapp2 were detected in fungal secretions. This study provides insights into the dynamic expression and regulation of Sapps in C. parapsilosis, highlighting a known virulence factor that is considered a potential target for drug development against this increasingly prominent pathogen.

Azole resistance in Aspergillus fumigatus (ARAf) is becoming a worldwide health threat due to increasing occurrence in the environment. However, environmental surveillance programs are not commonly in place and are lacking in Belgium. Since no data on the occurrence of ARAf and the presence of hotspots for the selection of azole resistance is available in Belgium, a first study on the prevalence of ARAf in the environment was conducted. A total of 232 air and compost or soil samples were taken from two composting facilities, and from horticultural and agricultural crops. The azole susceptibility pattern was determined using the EUCAST method (E. Def. 9.4), and the cyp51A gene and its promotor region were sequenced in A. fumigatus isolates with phenotypic azole resistance. Six pan-azole-resistant A. fumigatus isolates were identified, originating from compost and horticultural crops. Four isolates carried the TR34/L98H mutation, and one isolate carried the TR46/Y121F/T289A mutation. However, we did not observe any ARAf isolates from agricultural crops. In conclusion, this study reported the first TR34/L98H and TR46/Y121F/T289A mutation isolated from a composting facility and horticulture in Belgium. The implementation of standardization in environmental surveillance of A. fumigatus on a European level would be beneficial in order to identify hotspots.

Differently from immunocompromised patients, very little information is available in the literature regarding the clinical presentation, epidemiology, and outcomes of histoplasmosis in non-immunosuppressed individuals living in endemic areas. This retrospective case series study was carried out by reviewing the medical records of non-immunocompromised patients with histoplasmosis, residents in a hyperendemic area in northeastern Brazil, between 2011 and 2022. Thirty HIV-negative patients were identified with histoplasmosis, and 19 cases met the inclusion criteria: three had acute, five subacute and one chronic pulmonary forms; two with mediastinal picture and eight had disseminated disease (two with severe symptoms). The median age of our sample was 32.7 years old [interquartile range: 24-45]. Most of the patients were male (male-to-female ratio = 15:4) and resided in the state capital (n = 9). The majority had a previous history of exposure to well-known risk factors for Histoplasma infection. Pulmonary nodules were observed in all subacute form, two patients (acute and subacute forms) were initially treated empirically for pulmonary tuberculosis; one death was registered in the subacute form. The chronic pulmonary form of histoplasmosis was diagnosed in one patient only after the symptoms persisted despite specific treatment. The primary clinical manifestations of the moderate form of DH were enlarged lymph nodes, with histopathology being the main diagnostic method. The cases were detected as isolated occurrences and not as an outbreak, suggesting that exposure to Histoplasma can be more widespread than presumed. Despite the self-limiting nature of the disease, death can occur even in previously heathy patients.

Candida auris is an emerging fungal pathogen associated with multi-drug resistance rates and widespread outbreaks in hospitals and healthcare units worldwide. Sequencing studies have revealed that different clonal lineages of the fungus seem to be prevalent among distinct geographical sites. The first case of C. auris in Northern Greece was reported in Thessaloniki in October 2022, almost 2 years after the first isolation in Greece (Athens 2019). The Mycology Laboratory of the Medical School of Aristotle University of Thessaloniki stands as the reference laboratory for fungal diseases in Northern Greece and a meticulous search for the yeast, in plenty of suspicious samples, has been run since 2019 in the Lab as well as a retrospective analysis of all its yeasts' collection, back to 2008, with negative results for the presence of C. auris. Here, are presented the findings concerning the outbreak and surveillance of C. auris in Northern Greece, mainly the region of Thessaloniki and the broader area of Macedonia, from October 2022 until August 2023. The isolates from Northern Greece continue to fall in Clade I and present with an almost equal and stable sensitivity profile until now.

Trichophyton indotineae is an emerging species of the Trichophyton mentagrophytes complex (TMC), responsible for an epidemic of widespread hairless skin infections that is frequently (50-70%) resistant to terbinafine. In order to initiate appropriate treatment as quickly as possible without waiting for culture positivity (10-15 days) and molecular identification from the strain, we developed a dual quantitative PCR (qPCR) for the direct detection of T. indotineae in clinical samples. We first designed a T. indotineae-specific qPCR assay (TI-qPCR) targeting a single specific polymorphism in the internal transcribed spacer region. Although none of the 94 non-dermatophyte and 7 dermatophyte species were amplified, this TI-qPCR allowed amplification of other TMC species at a lower yield. With equal amounts (0.1 ng) of DNA per reaction, the mean quantitative cycle (Cq) values for T. indotineae and non-indotineae TMC were 27.9 (±0.1) and 38.9 (±0.3), respectively. Therefore, we normalized this assay against a previously validated pan-dermatophyte qPCR assay (PD-qPCR) and relied on the ΔCq [(TI-qPCR) - (PD-qPCR)] to identify T. indotineae versus other TMC species. Dual assay was validated using 86 clinical samples of culture-confirmed T. indotinea and 19 non-indotineae TMC cases. The mean ΔCq for non-indotineae TMC was 9.6 ± 2.7, whereas the ΔCq for T. indotinea was -1.46 ± 2.1 (P < .001). Setting the ΔCq at 4.5 as a cutoff value resulted in 100% specificity for the detection of T. indotineae. This dual qPCR assay quickly detects T. indotineae from skin scrapings, aiding in early diagnosis and treatment for patients with suspected infection.

The yeasts Cryptococcus neoformans and Cryptococcus gattii are fungal pathogens that can be isolated from the environment, including the surfaces of many plants. Cryptococcus gattii caused an outbreak on Vancouver Island, British Columbia beginning in 1999 that has since spread to the Pacific Northwest of the United States. Coastal Douglas fir (Pseudotsuga menziesii) is an important lumber species and a major component of the ecosystems in this area. Previous research has explored Cryptococcus survival and mating on Douglas fir plants and plant-derived material, but no studies have been done on the production of cryptococcal virulence factors by cells grown on those media. Here, we investigated the effects of growth on Douglas fir-derived media on the production of the polysaccharide capsule and melanin, two of the most important cryptococcal virulence factors. We found that while the capsule was mostly unchanged by growth in Douglas fir media compared to cells grown in defined minimal media, Cryptococcus spp. can use substrates present in Douglas fir to synthesize functional and protective melanin. These results suggest mechanisms by which Cryptococcus species may survive in the environment and emphasize the need to explore how association with Douglas fir trees could affect its epidemiology for human cryptococcosis.

Candida auris is an emerging fungal pathogen responsible for healthcare-associated infections and outbreaks with high mortality around the world. It readily colonizes the skin, nares, respiratory and urinary tract of hospitalized patients, and such colonization may lead to invasive Candida infection in susceptible patients. However, there is no recommended decolonization protocol for C. auris by international health authorities. The aim of this study is to evaluate the susceptibility of C. auris to commonly used synthetic and natural antiseptic products using an in vitro, broth microdilution assay. Synthetic antiseptics including chlorhexidine, povidone-iodine, and nystatin were shown to be fungicidal against C. auris. Among the natural antiseptics tested, tea tree oil and manuka oil were both fungicidal against C. auris at concentrations less than or equal to 1.25% (v/v). Manuka honey inhibited C. auris at 25% (v/v) concentrations. Among the commercial products tested, manuka body wash and mouthwash were fungicidal against C. auris at concentrations less than or equal to 0.39% (w/v) and 6.25% (v/v) of products as supplied for use, respectively, while tea tree body wash and MedihoneyTM wound gel demonstrated fungistatic properties. In conclusion, this study demonstrated good in vitro antifungal efficacy of tea tree oil, manuka oil, manuka honey, and commercially available antiseptic products containing these active ingredients. Future studies are warranted to evaluate the effectiveness of these antiseptic products in clinical settings.