Medically important pathogenic fungi invade vertebrate tissue and are considered primary when part of their nature life cycle is associated with an animal host and are usually able to infect immunocompetent hosts. Opportunistic fungal pathogens complete their life cycle in environmental habitats or occur as commensals within or on the vertebrate body, but under certain conditions can thrive upon infecting humans. The extent of host damage in opportunistic infections largely depends on the portal and modality of entry as well as on the host's immune and metabolic status. Diseases caused by primary pathogens and common opportunists, causing the top approximately 80% of fungal diseases [D. W. Denning, Lancet Infect Dis, 24:e428-e438, 2024, https://doi.org/10.1016/S1473-3099(23)00692-8], tend to follow a predictive pattern, while those by occasional opportunists are more variable. For this reason, it is recommended that diseases caused by primary pathogens and the common opportunists are named after the etiologic agent, for example, histoplasmosis and aspergillosis, while this should not be done for occasional opportunists that should be named as [causative fungus] [clinical syndrome], for example, Alternaria alternata cutaneous infection. The addition of a descriptor that identifies the location or clinical type of infection is required, as the general name alone may cover widely different clinical syndromes, for example, "rhinocerebral mucormycosis." A list of major recommended human and animal disease entities (nomenclature) is provided in alignment with their causative agents. Fungal disease names may encompass several genera of etiologic agents, consequently being less susceptible to taxonomic changes of the causative species, for example, mucormycosis covers numerous mucormycetous molds.
- MeSH
- houby * klasifikace patogenita MeSH
- lidé MeSH
- mykózy * mikrobiologie MeSH
- oportunní infekce mikrobiologie MeSH
- terminologie jako téma * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Spontaneous mycosis caused by Aureobasidium pullulans is documented in roach in a cyprinid-prevalent water reservoir in Czechia. Gross pathological lesions included pale gills and splenomegaly, as revealed during necropsy examination. Histological examination showed extensive foci with fungal elements in the kidney. The isolated fungus was identified through phenotypic and molecular characterization, including phylogeny. This report represents the first case of A. pullulans infection in fish and cold-blooded vertebrates, to the best of our knowledge.
- Publikační typ
- kazuistiky MeSH
Terbinafin, allylaminové antimykotikum, je léčivo první volby při systémové léčbě dermatofytóz. Inhibuje enzym skvalen-epoxidázu (SQLE), zapojený v biosyntetické dráze ergosterolu. Šíření terbinafinové rezistence u dermatofytů je nová výzva. Nejvyšší prevalence rezistence je popisována v Indii a jihovýchodní Asii, avšak rozšiřuje se globálně. Tato studie shrnuje data o rezistenci ze světa u druhů Trichophyton rubrum a T. mentagrophytes a porovnává je s daty z České republiky (ČR), včetně molekulárních mechanismů rezistence. V letech 2020–2021 bylo v ČR screeningovou metodou pro detekci rezistence testováno 514 kmenů T. rubrum a v letech 2018–2021 240 kmenů T. mentagrophytes. Rezistence byla zjištěna pouze u druhu T. mentagrophytes s prevalencí 2,5 %. Všechny rezistentní kmeny nesly mutaci F397L v genu SQLE a vykazovaly vysoké minimální inhibiční koncentrace k terbinafinu (≥ 4 mg/l). Vzhledem k relativně nízké prevalenci rezistence není nutné měnit současné postupy pro léčbu dermatofytóz v ČR, nicméně průběžné monitorování zůstává důležité.
Terbinafine, an allylamine antifungal agent, is the drug of first choice in the systemic treatment of dermatophytoses. It inhibits the enzyme squalene epoxidase (SQLE), involved in the ergosterol biosynthetic pathway. The spread of terbinafine resistance in dermatophytes is a new challenge. The highest prevalence of resistance is described in India and Southeast Asia, but it is spreading globally. This study summarizes resistance data from around the world in Trichophyton rubrum and T. mentagrophytes species and compares them with data from the Czech Republic, including molecular mechanisms of resistance. Between 2020 and 2021, 514 strains of T. rubrum and 240 strains of T. mentagrophytes have been screened for resistance in the Czech Republic. Resistance was detected only in T. mentagrophytes with a prevalence of 2.5%. All resistant strains carried the F397L mutation in the SQLE gene and showed high minimum inhibitory concentrations to terbinafine (≥ 4 mg/L). Due to the relatively low prevalence of resistance, there is no need to change the current management of dermatophytoses in the Czech Republic, but continuous monitoring remains important.
- MeSH
- antifungální látky farmakologie terapeutické užití MeSH
- Arthrodermataceae genetika patogenita účinky léků MeSH
- fungální léková rezistence * MeSH
- inhibitory enzymů farmakologie terapeutické užití MeSH
- lidé MeSH
- mikrobiální testy citlivosti statistika a číselné údaje MeSH
- mutace MeSH
- prevalence MeSH
- statistika jako téma MeSH
- terbinafin * farmakologie terapeutické užití MeSH
- tinea etiologie farmakoterapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
This study looked for correlations between molecular identification, clinical manifestation, and morphology for Trichophyton interdigitale and Trichophyton mentagrophytes. For this purpose, a total of 110 isolates were obtained from Czech patients with various clinical manifestations of dermatophytosis. Phenotypic characters were analyzed, and the strains were characterized using multilocus sequence typing. Among the 12 measured/scored phenotypic features, statistically significant differences were found only in growth rates at 37 °C and in the production of spiral hyphae, but none of these features is diagnostic. Correlations were found between T. interdigitale and higher age of patients and between clinical manifestations such as tinea pedis or onychomychosis. The MLST approach showed that internal transcribed spacer (ITS) genotyping of T. mentagrophytes isolates has limited practical benefits because of extensive gene flow between sublineages. Based on our results and previous studies, there are few taxonomic arguments for preserving both species names. The species show a lack of monophyly and unique morphology. On the other hand, some genotypes are associated with predominant clinical manifestations and sources of infections, which keep those names alive. This practice is questionable because the use of both names confuses identification, leading to difficulty in comparing epidemiological studies. The current identification method using ITS genotyping is ambiguous for some isolates and is not user-friendly. Additionally, identification tools such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry fail to distinguish these species. To avoid further confusion and to simplify identification in practice, we recommend using the name T. mentagrophytes for the entire complex. When clear differentiation of populations corresponding to T. interdigitale and Trichophyton indotineae is possible based on molecular data, we recommend optionally using a variety rank: T. mentagrophytes var. interdigitale and T. mentagrophytes var. indotineae.
- MeSH
- DNA fungální genetika chemie MeSH
- fenotyp MeSH
- fylogeneze MeSH
- mezerníky ribozomální DNA genetika chemie MeSH
- multilokusová sekvenční typizace veterinární MeSH
- sekvenční analýza DNA veterinární MeSH
- tinea * diagnóza veterinární MeSH
- Trichophyton MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
A mycotic infection manifesting as abdominal distension with free serous fluid accumulation in the coelomic cavity is documented in farmed rainbow trout. Histological examination using PAS and silver staining revealed the presence of numerous fungal hyphae in the spleen and gastrointestinal wall. The isolated fungus was sterile and identified by using phylogenetic analysis based on four loci as Neopyrenochaeta submersa. This is the first time this fungus has been reported as pathogen.
- Publikační typ
- kazuistiky MeSH
This study was designed to evaluate the prevalence of antifungal resistance, genetic mechanisms associated with in vitro induction of azole and echinocandin resistance and genotyping of Candida krusei, which is intrinsically resistant to fluconazole and is recovered from clinical and nonclinical sources from different countries. Our results indicated that all the isolates were susceptible or had the wild phenotype (WT) to azoles, amphotericin B, and only 1.27% showed non-WT for flucytosine. Although 70.88% of the isolates were resistant to caspofungin, none of them were categorized as echinocandin-resistant as all were susceptible to micafungin and no FKS1 hot spot 1 (HS1) or HS2 mutations were detected. In vitro induction of azole and echinocandin resistance confirmed the rapid development of resistance at low concentrations of fluconazole (4 μg/ml), voriconazole (0.06 μg/ml), and micafungin (0.03 μg/ml), with no difference between clinical and nonclinical isolates in the resistance development. Overexpression of ABC1 gene and FKS1 HS1 mutations were the major mechanisms responsible for azole and echinocandin resistance, respectively. Genotyping of our 79 isolates coupled with 217 other isolates from different sources and geography confirmed that the isolates belong to two main subpopulations, with isolates from human clinical material and Asia being more predominant in cluster 1, and environmental and animals isolates and those from Europe in cluster 2. Our results are of critical concern, since realizing that the C. krusei resistance mechanisms and their genotyping are crucial for guiding specific therapy and for exploring the potential infection source.
- MeSH
- antifungální látky farmakologie terapeutické užití MeSH
- azoly * farmakologie MeSH
- echinokandiny * farmakologie MeSH
- fungální léková rezistence genetika MeSH
- genotyp MeSH
- mikrobiální testy citlivosti MeSH
- Pichia MeSH
- prevalence MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This article reports the first verified cases of infection by Trichophyton bullosum in Africa since the description of the fungus, isolated in 1933 from the coat of horses in Tunisia and Mali. We found the fungus in cutaneous samples obtained from donkeys suffering from severe dermatitis with areas of alopecia and scaling in the surroundings of Cairo (Egypt). Fungal elements (arthroconidia and hyphae) were seen at the microscopy of material collected by skin scraping and digested in NaOH. Fungal colonies grown on various culture media were identified through PCR and sequencing of the ITS rDNA region. Since the original report in Africa and the Middle East, only a few cases have been reported thus far in humans in France and two cases in horses in the Czech Republic and Japan. Trichophyton bullosum seems thus an infrequent cause of dermatophytosis. However, the actual prevalence of this pathogen may be underestimated due to the similarity with T. verrucosum, a predominant cause of infection in cattle, occasionally found on horses and donkeys. Indeed, the two fungi can be distinguished only via molecular methods, which are poorly employed in epidemiological studies on equine and bovine dermatophytosis. The present study results add to our knowledge on the ecology of this poorly explored dermatophyte, supporting the concept that equines are the primary hosts of T. bullosum and confirming the presence of this pathogen in Africa. At the same time, these are the first unequivocally documented infections in donkeys due to T. bullosum.
- MeSH
- Arthrodermataceae * genetika MeSH
- Equidae MeSH
- koně MeSH
- skot MeSH
- tinea * epidemiologie mikrobiologie veterinární MeSH
- Trichophyton genetika MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- severní Afrika MeSH
Cannabis preparations are gaining popularity among patients with various skin diseases. Due to the lack of scientific evidence, dermatologists remain cautious about their prescriptions. So far, only a few studies have been published about the effects of high-potency cannabis extracts on microorganisms (especially dermatophytes) causing skin problems that affect more than 25% of the worldwide population. Even though, the high-potency cannabis extracts prepared by cold extraction are mostly composed of non-psychoactive tetrahydrocannabinolic acid (THCA) and only low amount of THC, their use in topical treatment can be stigmatized. The in vitro antimicrobial and antifungal activity of two high potent cannabis strains extracted by three solvents traditionally or currently used by cannabis users (ethanol; EtOH, butane; BUT, dimethyl ether; DME) was investigated by broth dilution method. The chemical profile of cannabis was determined by high-performance liquid chromatography with ultraviolet detection and gas chromatography with mass spectrometer and flame ionization detector. The extraction methods significantly influenced chemical profile of extracts. The yield of EtOH extracts contained less cannabinoids and terpenes compared to BUT and DME ones. Most of the extracts was predominantly (>60%) composed of various cannabinoids, especially THCA. All of them demonstrated activity against 18 of the 19 microorganisms tested. The minimal inhibitory concentrations (MICs) of the extracts ranged from 4 to 256 μg/mL. In general, the bacteria were more susceptible to the extracts than dermatophytes. Due to the lower content of biologically active substances, the EtOH extracts were less effective against microorganisms. Cannabis extracts may be of value to treat dermatophytosis and other skin diseases caused by various microorganisms. Therefore, they could serve as an alternative or supportive treatment to commonly used antibiotics.
- Publikační typ
- časopisecké články MeSH
The fungal cell wall, comprised primarily of protein and polymeric carbohydrate, maintains cell structure, provides protection from the environment, and is an important antifungal drug target. Pir proteins (proteins with internal repeats) are linked to cell wall β-1,3-glucan and are best studied in Saccharomyces cerevisiae. Sequential deletion of S. cerevisiae PIR genes produces strains with increasingly notable cell wall damage. However, a true null mutant lacking all five S. cerevisiae PIR genes was never constructed. Because only two PIR genes (PIR1, PIR32) were annotated in the Candida albicans genome, the initial goal of this work was to construct a true Δpir/Δpir null strain in this species. Unexpectedly, the phenotype of the null strain was almost indistinguishable from its parent, leading to the search for other proteins with Pir function. Bioinformatic approaches revealed nine additional C. albicans proteins that share a conserved Pir functional motif (minimally DGQ). Examination of the protein sequences revealed another conserved motif (QFQFD) toward the C-terminal end of each protein. Sequence similarities and presence of the conserved motif(s) were used to identify a set of 75 proteins across 16 fungal species that are proposed here as Pir proteins. The Pir family is greatly expanded in C. albicans and C. dubliniensis compared to other species and the orthologs are known to have specialized function during chlamydospore formation. Predicted Pir structures showed a conserved core of antiparallel beta-sheets and sometimes-extensive loops that contain amino acids with the potential to form linkages to cell wall components. Pir phylogeny demonstrated emergence of specific ortholog groups among the fungal species. Variation in gene expression patterns was noted among the ortholog groups during growth in rich medium. PIR allelic variation was quite limited despite the presence of a repeated sequence in many loci. Results presented here demonstrate that the Pir family is larger than previously recognized and lead to new hypotheses to test to better understand Pir proteins and their role in the fungal cell wall.
Tento návrh doporučeného postupu laboratorní diagnostiky dermatomykóz byl vypracován na základě odborné diskuze členů Pracovní skupiny pro mykologii Společnosti pro lékařskou mikrobiologii České lékařské společnosti JEP (PSM SLM ČLS JEP). Vychází z dokumentu „Doporučený postup laboratorní diagnostiky dermatomykóz“ zveřejněného na webových stránkách SLM ČLS JEP 23. 6. 2020 k všeobecné odborné diskuzi. Dosud byly pokyny v této oblasti mykologické laboratorní diagnostiky omezeny pouze na informace v příručkách a neexistoval žádný ucelený a systematický dokument na uvedené téma. Tuto mezeru se členové PSM SLM ČLS JEP snažili zaplnit, a vzniklo tak doporučení, pokrývající všechny části dermatomykologické laboratorní problematiky, od způsobu získání kvalitní anamnézy, správného postupu při odběru vzorků, jejich vyšetřování konvenčními mikroskopickými a kultivačními technikami, až po interpretaci získaných výsledků. Do této základní osnovy byly začleněny informace o diagnostickém potenciálu nových, moderních technologií, zejména molekulárně genetických metod a hmotnostní spektrometrie. Nedávno došlo k vypracování standardní evropské metodiky pro testování citlivosti dermatofytů k antimykotikům, proto byla i tato problematika do doporučení zahrnuta. Je samozřejmě počítáno s budoucí periodickou revizí tohoto dokumentu na základě nových poznatků.
This draft of guidelines for the laboratory diagnosis of dermatomycoses was developed based on discussion among members of the Czech Society for Medical Microbiology Working Group on Mycology. The document Guidelines for the Laboratory Diagnosis of Dermatomycoses was published for discussion on the Czech Society for Medical Microbiology website on 23 March 2020. Until recently, recommendations concerning this area of laboratory diagnosis in mycology were only limited to information in manuals and no comprehensive and systematic document concerning these issues was available. In an effort to fill the gap, members of the working group developed recommendations covering various laboratory aspects of mycology, from obtaining a proper history, to adequate sampling techniques, sample analyses using conventional microscopy and culture techniques, to interpretation of results. Additional information was on the diagnostic potential of novel, modern technology, in particular molecular genetic methods and mass spectrometry. The recently developed European standards for testing the susceptibility of dermatophytes to antifungals were also included in the recommendations. The document will be regularly updated based on new findings.
