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Due to large outbreaks observed worldwide, Candida auris has emerged as a major threat to healthcare facilities. To prevent these phenomena, a systematic screening should be performed in patients transferred from regions where the pathogen is highly endemic. In this study, we recorded and analyzed French mycologists' current knowledge and practice regarding C. auris screening and diagnosis. Thirty-six centers answered an online questionnaire. Only 11 (30.6 %) participants were aware of any systematic screening for C. auris for patients admitted to their hospital. In the case of post-admission screening, axillae/groins (n = 21), nares (n = 7), rectum (n = 9), and mouth (n = 6) alone or various combinations were the body sites the most frequently sampled. Only six centers (8.3 %) reported using a commercially available plate allowing the differentiation of C. auris colonies from that of other Candida species, while five laboratories (13.8 %) had implemented a C. auris-specific qPCR. Considering the potential impact on infected patients and the risk of disorganization in the care of patients, it is crucial to remember to biologists and clinicians the utmost importance of systematic screening on admission.
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Data on the epidemiology of tinea capitis (TC), an infection of the scalp by dermatophytes, are scarce in Cameroon. This study aimed to determine the prevalence of TC among school-children in the Dschang Subdivision, Western Cameroon. A cross-sectional study was carried out in June 2021 in Dschang including pupils aged 5-13. First, a standardized questionnaire was administered to participant for the collection of sociodemographic data. Then, samples were collected and cultured onto Sabouraud-Chloramphenicol-Gentamicin Agar. The etiological agents were identified based on their morphological features and with MALDI-TOF mass spectrometry. A total of 1070 children were clinically examined and 108 (10.1%) children presented with TC lesions. The mean age of the 1070 participants was 8.3 ± 2.6 years (range: 5-13 years); 772 (72.2%) were males. The use of borehole water (OR = 0.01, 95%CI[0.001-0.03]), spring water (OR = 0.2, 95%CI[0.08-0.50]), rainwater (OR = 0.004, 95%CI[0.001-0.016]), and hairdressing salons visits (OR = 0.413, 95%CI[0.196-0.872]) were associated with a decreased TC risk in the multivariate logistic regression analysis. In contrast, sharing bed with siblings (OR = 4.48, 95%CI[2.095-9.60]) was associated with an increased TC risk in children. Among the 32 dermatophytes isolated in culture, Microsporum audouinii was the most frequent (43.8%), followed by Trichophyton rubrum (25.0%) and T. soudanense (25.0%). Microsporum canis and T. violaceum were both rarely isolated. Further studies are warranted to assess the association of TC with domestic water usage that has been highlighted in this study.
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Tiña del Cuero Cabelludo , Tiña del Cuero Cabelludo/epidemiología , Tiña del Cuero Cabelludo/microbiología , Humanos , Camerún/epidemiología , Niño , Masculino , Femenino , Adolescente , Estudios Transversales , Preescolar , Prevalencia , Encuestas y Cuestionarios , Microsporum/aislamiento & purificación , Factores de Riesgo , Arthrodermataceae/aislamiento & purificación , Arthrodermataceae/clasificación , Instituciones Académicas , Trichophyton/aislamiento & purificaciónRESUMEN
The nomenclature and phylogeny of dermatophytes is currently based on the nucleotide sequence polymorphisms of a few genomic regions. However, the limitations of this multilocus sequence-based approach makes dermatophyte species identification difficult. Variation and adaptation are key to the persistence of species. Nevertheless, this heterogeneity poses a genuine problem for the classification and nomenclature of dermatophytes. The relatively high intra-species and low inter-species polymorphisms of this keratinophilic group of fungi hampers both species delineation and identification. Establishing the taxonomic boundaries of dermatophyte species complexes remains controversial. Furthermore, until recently, knowledge of molecular biology, genetics and genomics remained limited. This systematic review highlights the added value of whole genome sequencing and analysis data in dermatophyte classification that might enhance identification and, consequently, the diagnosis and management of dermatophytoses. Our approach consisted in describing and comparing the dermatophyte mitochondrial genomes, secretomes (Adhesins, LysM domains, proteases) and metabolic pathways, with the aim to provide new insights and a better understanding of the phylogeny and evolution of dermatophytes.
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Arthrodermataceae , Arthrodermataceae/genética , Análisis de Secuencia de ADN , Filogenia , Genómica , Secuenciación Completa del GenomaRESUMEN
The present study employed data collected during the Mycosands survey to investigate the environmental factors influencing yeasts and molds distribution along European shores applying a species distribution modelling approach. Occurrence data were compared to climatic datasets (temperature, precipitation, and solar radiation), soil datasets (chemical and physical properties), and water datasets (temperature, salinity, and chlorophyll-a concentration) downloaded from web databases. Analyses were performed by MaxEnt software. Results suggested a different probability of distribution of yeasts and molds along European shores. Yeasts seem to tolerate low temperatures better during winter than molds and this reflects a higher suitability for the Northern European coasts. This difference is more evident considering suitability in waters. Both distributions of molds and yeasts are influenced by basic soil pH, probably because acidic soils are more favorable to bacterial growth. Soils with high nitrogen concentrations are not suitable for fungal growth, which, in contrast, are optimal for plant growth, favored by this environment. Finally, molds show affinity with soil rich in nickel and yeasts with soils rich in cadmium resulting in a distribution mainly at the mouths of European rivers or lagoons, where these metals accumulate in river sediments.
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Ríos , Contaminantes del Suelo , Ríos/química , Suelo/química , Cadmio/análisis , Contaminantes del Suelo/análisis , Metales/análisis , Levaduras , Monitoreo del AmbienteRESUMEN
The goal of most studies published on sand contaminants is to gather and discuss knowledge to avoid faecal contamination of water by run-offs and tide-retractions. Other life forms in the sand, however, are seldom studied but always pointed out as relevant. The Mycosands initiative was created to generate data on fungi in beach sands and waters, of both coastal and freshwater inland bathing sites. A team of medical mycologists and water quality specialists explored the sand culturable mycobiota of 91 bathing sites, and water of 67 of these, spanning from the Atlantic to the Eastern Mediterranean coasts, including the Italian lakes and the Adriatic, Baltic, and Black Seas. Sydney (Australia) was also included in the study. Thirteen countries took part in the initiative. The present study considered several fungal parameters (all fungi, several species of the genus Aspergillus and Candida and the genera themselves, plus other yeasts, allergenic fungi, dematiaceous fungi and dermatophytes). The study considered four variables that the team expected would influence the results of the analytical parameters, such as coast or inland location, urban and non-urban sites, period of the year, geographical proximity and type of sediment. The genera most frequently found were Aspergillus spp., Candida spp., Fusarium spp. and Cryptococcus spp. both in sand and in water. A site-blind median was found to be 89 Colony-Forming Units (CFU) of fungi per gram of sand in coastal and inland freshwaters, with variability between 0 and 6400 CFU/g. For freshwater sites, that number was 201.7 CFU/g (0, 6400 CFU/g (p = 0.01)) and for coastal sites was 76.7 CFU/g (0, 3497.5 CFU/g). For coastal waters and all waters, the median was 0 CFU/ml (0, 1592 CFU/ml) and for freshwaters 6.7 (0, 310.0) CFU/ml (p < 0.001). The results advocate that beaches should be monitored for fungi for safer use and better management.
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Playas , Arena , Australia , Mar Negro , Hongos , Humanos , Italia , Microbiología del AguaRESUMEN
Mycobacterium ulcerans secrete a series of non-ribosomal-encoded toxins known as mycolactones that are responsible for causing a disabling ulceration of the skin and subcutaneous tissues named Buruli ulcer. The disease is the sole non-contagion among the three most common mycobacterial diseases in humans. Direct contact with contaminated wetlands is a risk factor for Buruli ulcer, responsible for M. ulcerans skin carriage before transcutaneous inoculation with this opportunistic pathogen. In this study, we analysed the bacterial and fungal skin microbiota in individuals exposed to M. ulcerans in Burkina Faso. We showed that M. ulcerans-specific DNA sequences were detected on the unbreached skin of 6/52 (11.5%) asymptomatic farmers living in Sindou versus 0/52 (0%) of those living in the non-endemic region of Tenkodogo. Then, we cultured the skin microbiota of asymptomatic M. ulcerans carriers and negative control individuals, all living in the region of Sindou. A total of 84 different bacterial and fungal species were isolated, 21 from M. ulcerans-negative skin samples, 31 from M. ulcerans-positive samples and 32 from both. More specifically, Actinobacteria, Aspergillus niger and Aspergillus flavus were significantly associated with M. ulcerans skin carriage. We further observed that in vitro, mycolactones induced spore germination of A. flavus, attracting the fungal network. These unprecedented observations suggest that interactions with fungi may modulate the outcome of M. ulcerans skin carriage, opening new venues to the understanding of Buruli ulcer pathology, prophylaxis and treatment of this still neglected tropical infection.
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Aspergilosis/epidemiología , Úlcera de Buruli/epidemiología , Piel/microbiología , Aspergillus/genética , Aspergillus/patogenicidad , Burkina Faso/epidemiología , Úlcera de Buruli/microbiología , ADN Bacteriano/genética , Hongos/genética , Humanos , Microbiota/genética , Mycobacterium ulcerans/patogenicidad , Piel/metabolismoRESUMEN
To determine fungal species distribution of interdigital intertrigo among seafarers in Dakar, Senegal, a cross-sectional study was carried out from May to August 2017 among seafarers clinically diagnosed with interdigital intertrigo. A questionnaire was filled to each patient before sampling the affected folds and transporting to Aristide Le Dantec University Hospital where mycological analyses were realized. Species identification by MALDI-TOF MS was performed in Marseille, France. In total, 169 men (21-66 years) were included. Few of them (3%) had a high level of education and the duration of the mycosis exceed 10 years for 88% of patients. Direct microscopic examination (ME) was positive in 34.3%. Among samples with positive ME, 58.6% had positive culture. An overall incidence of 30.2% was found. Patients with confirmed cases aged between 28 and 66 years. Among them, those between 36-50 years were predominant (52.9%). Those with a high level of education were less representative (2%). For 52.1% of patients, the duration of the mycosis was superior to 10 years. Furthermore, 57% of cases were significantly associated with other types of tinea pedis and/or onychomycosis (P=0.03). Culture was positive in 23.7% isolating 43 strains successfully identified at the species level by MALDI-TOF MS for 31 isolates: 20 Candida and 11 dermatophytes. The rest was identified only at the genus level belonged to Fusarium. In definitive, MALDI-TOF MS could be a useful tool for routine and fast identification of dermatophytes, yeasts and NDFF in clinical mycology laboratories.
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Dermatosis del Pie/microbiología , Intertrigo/microbiología , Personal Militar , Técnicas de Tipificación Micológica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Adulto , Anciano , Candida/aislamiento & purificación , Estudios Transversales , Dermatosis del Pie/epidemiología , Humanos , Intertrigo/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Personal Militar/estadística & datos numéricos , Onicomicosis/epidemiología , Onicomicosis/microbiología , Senegal/epidemiología , Tiña del Pie/epidemiología , Tiña del Pie/microbiología , Viaje , Trichophyton/clasificación , Trichophyton/aislamiento & purificación , Adulto JovenRESUMEN
Aspergillus niger, the third species responsible for invasive aspergillosis, has been considered as a homogeneous species until DNA-based identification uncovered many cryptic species. These species have been recently reclassified into the Aspergillus section Nigri However, little is yet known among the section Nigri about the species distribution and the antifungal susceptibility pattern of each cryptic species. A total of 112 clinical isolates collected from 5 teaching hospitals in France and phenotypically identified as A. niger were analyzed. Identification to the species level was carried out by nucleotide sequence analysis. The MICs of itraconazole, voriconazole, posaconazole, isavuconazole, and amphotericin B were determined by both the EUCAST and gradient concentration strip methods. Aspergillus tubingensis (n = 51, 45.5%) and Aspergillus welwitschiae (n = 50, 44.6%) were the most common species while A. niger accounted for only 6.3% (n = 7). The MICs of azole drugs were higher for A. tubingensis than for A. welwitschiae The MIC of amphotericin B was 2 mg/liter or less for all isolates. Importantly, MICs determined by EUCAST showed no correlation with those determined by the gradient concentration strip method, with the latter being lower than the former (Spearman's rank correlation tests ranging from 0.01 to 0.25 depending on the antifungal agent; P > 0.4). In conclusion, A. niger should be considered as a minority species in the section Nigri The differences in MICs between species for different azoles underline the importance of accurate identification. Significant divergences in the determination of MIC between EUCAST and the gradient concentration strip methods require further investigation.
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Antifúngicos , Itraconazol , Antifúngicos/farmacología , Aspergillus , Francia , Pruebas de Sensibilidad MicrobianaRESUMEN
A survey of mycology laboratories for antifungal susceptibility testing (AFST) was undertaken in France in 2018, to better understand the difference in practices between the participating centers and to identify the difficulties they may encounter as well as eventual gaps with published standards and guidelines. The survey captured information from 45 mycology laboratories in France on how they perform AFST (number of strains tested, preferred method, technical and quality aspects, interpretation of the MIC values, reading and interpretation difficulties). Results indicated that 86% of respondents used Etest as AFST method, with a combination of one to seven antifungal agents tested. Most of the participating laboratories used similar technical parameters to perform their AFST method and a large majority used, as recommended, internal and external quality assessments. Almost all the participating mycology laboratories (98%) reported difficulties to interpret the MIC values, especially when no clinical breakpoints are available. The survey highlighted that the current AFST practices in France need homogenization, particularly for MIC reading and interpretation.
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Antifúngicos/uso terapéutico , Laboratorios , Pruebas de Sensibilidad Microbiana , Micología , Práctica Profesional/estadística & datos numéricos , Pruebas Antimicrobianas de Difusión por Disco/métodos , Pruebas Antimicrobianas de Difusión por Disco/normas , Pruebas Antimicrobianas de Difusión por Disco/estadística & datos numéricos , Farmacorresistencia Fúngica , Francia , Historia del Siglo XXI , Humanos , Laboratorios/normas , Laboratorios/estadística & datos numéricos , Ensayos de Aptitud de Laboratorios/métodos , Ensayos de Aptitud de Laboratorios/estadística & datos numéricos , Pruebas de Sensibilidad Microbiana/métodos , Pruebas de Sensibilidad Microbiana/normas , Pruebas de Sensibilidad Microbiana/estadística & datos numéricos , Micología/historia , Micología/métodos , Micología/normas , Micología/estadística & datos numéricos , Práctica Profesional/normas , Control de Calidad , Encuestas y CuestionariosRESUMEN
By choosing a capacity-building strategy based on human resources, the late Professor Ogobara Doumbo and Professor Yeya Toure have succeeded in establishing a center devoted to malaria research in the economically unfavorable environment of Mali. By taking advantage of the advent of a pluralist democracy in Mali in 1991, the Malaria Research and Training Centre (MRTC) has become a model of excellence in training in biomedical research and a renowned clinical research center. Since 2003, MRTC researchers have conducted more than 20 phase-1 and -2 clinical trials of antimalarial vaccines, thus becoming a reference both in Africa and globally. The MRTC owes its success to several factors. While the focus on human capacity building has been critical for sustainability, the quality of the partnerships and the density of the partnership network have also played a critical role. The NIH partnership enabled us to construct new buildings to house modern laboratories. These facilities made it possible to conduct leading-edge research programs, the results of which in turn provided access to significant other funding sources, not only to finance new projects, but also to purchase modern heavy equipment. Lastly, it has been possible to set up a policy for training Malian researchers at the Masters and PhD levels, with the aim of fueling a critical mass of scientific expertise. The combination of each of these factors has created an environment conducive to sustainable research and whose recent results have heightened expectations for a rich future.
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Academias e Institutos/organización & administración , Investigación Biomédica , Laboratorios/organización & administración , Malaria , Investigación Biomédica/educación , Investigación Biomédica/organización & administración , Recursos en Salud , Humanos , Malaria/prevención & control , MalíRESUMEN
Dermatophytic mycetoma of the scalp is a rarity, especially when not associated with tinea capitis. Here, we report a case of dermatophytic mycetoma of the scalp, that was not associated with tinea capitis, caused by an atypical Microsporum audouinii strain. To our knowledge, this is the second reported case, thirty-eight years after the first that was published in 1980.
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Dermatomicosis/diagnóstico , Microsporum/aislamiento & purificación , Micetoma/diagnóstico , Micetoma/microbiología , Cuero Cabelludo/microbiología , Adulto , Antifúngicos/uso terapéutico , Biopsia , ADN Intergénico/genética , Dermatomicosis/tratamiento farmacológico , Femenino , Humanos , Microsporum/efectos de los fármacos , Microsporum/genética , Micetoma/tratamiento farmacológico , Cuero Cabelludo/patología , Senegal , Análisis de Secuencia de ADN , Piel/patología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
AIMS: Candida albicans biofilms are commonly associated with severe oral infections. We previously discovered that a crude extract from the Solidago virgaurea plant (SV extract) was a potent inhibitor of C. albicans biofilm formation. Here, we further investigate the mechanisms underlying C. albicans biofilm inhibition by the SV extract. METHODS AND RESULTS: The SV extract was shown to inhibit laboratory and clinical C. albicans isolates adherence and hyphal transition on inert support and epithelial human cells, without affecting viability and growth of planktonic yeasts. Interestingly, RT-PCR-based experiments demonstrated that some key genes involved in adhesion and hyphal morphological switch (e.g. Hwp1p, Ece1p, Als3p) were strongly down-regulated by the SV extract. Moreover, antimicrobial synergy testing (checkerboard assay) demonstrated that antifungal effects of miconazole, nystatin or a common antiseptic mouthwash were synergistically improved when used in combination with the SV extract. CONCLUSIONS: The SV extract prevents C. albicans biofilm formation through direct inhibition of key adherence and hyphae-associated genes. SIGNIFICANCE AND IMPACT OF THE STUDY: Biofilm is considered as a key virulence factor of C. albicans infection. Our discovery of an inhibitor specifically acting on genes involved in biofilm formation paves the way for the future development of a new class of antifungal product.
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Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida albicans/genética , Extractos Vegetales/farmacología , Solidago/química , Antifúngicos/farmacología , Células Cultivadas , Sinergismo Farmacológico , Expresión Génica/efectos de los fármacos , Humanos , Hifa/efectos de los fármacos , Miconazol/farmacología , Nistatina/farmacología , Extractos Vegetales/químicaRESUMEN
There is a scarcity of recent epidemiological data on intestinal parasitic infections in France. We conducted a prospective study aimed at estimating the prevalence of 10 enteric parasites in Marseille, France, using real-time polymerase chain reaction (PCR)-based diagnosis. A total of 643 faeces from 488 patients referred to the Parasitology-Mycology Laboratory of the University Hospital of Marseille over a 6 months period were included. DNA was extracted using a semi-automated method. Parasites of interest were detected using singleplex quantitative PCRs (qPCRs). For positive samples, the Blastocystis subtype was determined by sequence analysis. During the study, the overall prevalence of enteric parasites was 17%. Blastocystis sp. was the most frequent species (10.5%), followed by Dientamoeba fragilis (2.3%) and Giardia intestinalis (2.3%). The prevalence of other parasites was <1% each. The ST3 Blastocystis subtype was predominant (43.6%) and the other subtypes identified were ST1, ST2, ST4 and ST6. This is the first time that a qPCR-based diagnosis has been used to survey the prevalence of 10 enteric parasites in a French University Hospital. This study confirms that fast, specific, sensitive and simultaneous detection in a single stool sample by qPCR clearly outperforms conventional microscopy-based diagnosis. Furthermore, qPCR is particularly well suited to surveying gastroenteritis agents.
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Heces/parasitología , Parasitosis Intestinales/epidemiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Francia/epidemiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Adulto JovenRESUMEN
Fungus ball is the most common form of non-invasive fungal rhinosinusitis. Aspergillusfumigatus (between 44.8% and 75%) and Aspergillusflavus (14%) are the two most common species recovered. However, recent advances in mycological laboratory methods have enhanced the detection and identification of fungi within fungus balls. Fusarium species, sometimes recovered from other forms of fungal rhinosinusitis such as allergic fungal rhinosinusitis or acute invasive fungal rhinosinusitis, are poorly associated with sinonasal fungus ball. Here, we describe two further cases of a fungus ball due to Fusariumproliferatum and provide the first description of this fungal pathogen with a fungus ball of odontogenic origin. These case reports demonstrate that uncommon fungal species such as Fusarium spp. might be underestimated as agents of sinusal cavity fungus ball. Enhanced mycological detection and diagnostic techniques might give rise, in the near future, to the emergence of new or rare fungal species associated with this clinical entity.
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Fusarium/aislamiento & purificación , Sinusitis Maxilar/microbiología , Membrana Mucosa/microbiología , Rinitis/diagnóstico , Sinusitis/diagnóstico , Femenino , Fusarium/patogenicidad , Humanos , Sinusitis Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Membrana Mucosa/cirugía , Rinitis/microbiología , Sinusitis/microbiología , Tomografía Computarizada por Rayos XRESUMEN
Human mansonellosis is caused by M. perstans, M. ozzardi and M. streptocerca, the three main filarial species in the genus Mansonella. Despite accumulating evidence of a high prevalence in endemic areas, there is currently no filariasis control programme targeting mansonellosis. The health-related impact on people living with these filariae remains unknown, and evidences regarding treatment strategies are scarce. Like other neglected diseases, it mainly affects poor populations living in tropical and subtropical climates. Mansonellosis can be considered one of the most neglected tropical infectious diseases. The objective of this literature review was to draw attention to the gap of knowledge regarding Mansonella spp. taxonomy, the transmission of these arthropod-borne filariasis and the health outcomes of people living with mansonellosis.
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Pityriasis versicolor (PV) is a superficial mycosis caused by yeast of the genus Malassezia. The most common isolated Malassezia species in PV lesions differ among M. furfur, M. globosa and M. sympodialis. We purpose to determine the distribution of Malassezia species in PV patients at the seafarers' medical service in Dakar, Senegal and to examine whether any association between identified Malassezia species and patients' profile. From May 2017 to August 2017, first a questionnaire was filled to get informative data before collection of skin scrapings taken from most scaly site using sterile scalpel blade and application of scotch® for direct examination (DE). At the laboratory, DE, culture and identification by MALDI-TOF MS were done. One hundred patients with PV - all men - were included with a mean age of 34 years. Among seafarers, 81% were sailors. Clinical prevalence of PV was highest in aged adults patients with ages of 31 to 60 years (56%). Seafarers with high level of education were less representative with only 2%. The mean duration of the PV was 26.83 months. 20% of subjects suffered lesions in more than one location. The chest was the most affected anatomical site. Furthermore, possible predisposing factors associated with PV were also detected. DE was positive in 95% but culture growth only in 46%. MALDI-TOF MS analysis of the positive cultures could be performed in 84.8% (39/46). Only M. furfur was identified in 100% (39/39). In definitive, M. furfur is the only causative agent of PV in Dakar.
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Malassezia/clasificación , Malassezia/aislamiento & purificación , Tiña Versicolor/microbiología , Adolescente , Adulto , Humanos , Malassezia/genética , Masculino , Persona de Mediana Edad , Personal Militar/estadística & datos numéricos , Prevalencia , Factores de Riesgo , Senegal/epidemiología , Piel/microbiología , Piel/patología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tiña Versicolor/epidemiología , Tiña Versicolor/patología , Adulto JovenRESUMEN
Conventional dermatophyte identification is based on morphological features. However, recent studies have proposed to use the nucleotide sequences of the rRNA internal transcribed spacer (ITS) region as an identification barcode of all fungi, including dermatophytes. Several nucleotide databases are available to compare sequences and thus identify isolates; however, these databases often contain mislabeled sequences that impair sequence-based identification. We evaluated five of these databases on a clinical isolate panel. We selected 292 clinical dermatophyte strains that were prospectively subjected to an ITS2 nucleotide sequence analysis. Sequences were analyzed against the databases, and the results were compared to clusters obtained via DNA alignment of sequence segments. The DNA tree served as the identification standard throughout the study. According to the ITS2 sequence identification, the majority of strains (255/292) belonged to the genus Trichophyton, mainly T. rubrum complex (n = 184), T. interdigitale (n = 40), T. tonsurans (n = 26), and T. benhamiae (n = 5). Other genera included Microsporum (e.g., M. canis [n = 21], M. audouinii [n = 10], Nannizzia gypsea [n = 3], and Epidermophyton [n = 3]). Species-level identification of T. rubrum complex isolates was an issue. Overall, ITS DNA sequencing is a reliable tool to identify dermatophyte species given that a comprehensive and correctly labeled database is consulted. Since many inaccurate identification results exist in the DNA databases used for this study, reference databases must be verified frequently and amended in line with the current revisions of fungal taxonomy. Before describing a new species or adding a new DNA reference to the available databases, its position in the phylogenetic tree must be verified.
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Arthrodermataceae/clasificación , Arthrodermataceae/genética , Código de Barras del ADN Taxonómico/métodos , Dermatomicosis/microbiología , Arthrodermataceae/aislamiento & purificación , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Dermatomicosis/diagnóstico , Humanos , Filogenia , Estudios Prospectivos , Análisis de Secuencia de ADNRESUMEN
Aspergillus section Terrei is a species complex currently comprised of 14 cryptic species whose prevalence in clinical samples as well as antifungal susceptibility are poorly known. The aims of this study were to investigate A. Terrei clinical isolates at the species level and to perform antifungal susceptibility analyses by reference and commercial methods. Eighty-two clinical A. Terrei isolates were collected from 8 French university hospitals. Molecular identification was performed by sequencing parts of beta-tubulin and calmodulin genes. MICs or minimum effective concentrations (MECs) were determined for 8 antifungal drugs using both EUCAST broth microdilution (BMD) methods and concentration gradient strips (CGS). Among the 79 A. Terrei isolates, A. terreus stricto sensu (n = 61), A. citrinoterreus (n = 13), A. hortai (n = 3), and A. alabamensis (n = 2) were identified. All strains had MICs of ≥1 mg/liter for amphotericin B, except for two isolates (both A. hortai) that had MICs of 0.25 mg/liter. Four A. terreus isolates were resistant to at least one azole drug, including one with pan-azole resistance, yet no mutation in the CYP51A gene was found. All strains had low MECs for the three echinocandins. The essential agreements (EAs) between BMD and CGS were >90%, except for those of amphotericin B (79.7%) and itraconazole (73.4%). Isolates belonging to the A section Terrei identified in clinical samples show wider species diversity beyond the known A. terreus sensu stricto Azole resistance inside the section Terrei is uncommon and is not related to CYP51A mutations here. Finally, CGS is an interesting alternative for routine antifungal susceptibility testing.
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Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Aspergillus/genética , Anfotericina B/farmacología , Azoles/farmacología , Equinocandinas/farmacología , Humanos , Itraconazol/farmacología , Pruebas de Sensibilidad MicrobianaRESUMEN
The Penicillium genera, encompassing about 225 different species of fungi, are naturally present in the environment. These genera are poorly linked to human disease, except for Penicillium marneffei causing septicemia in immunocompromised hosts. Thus, Penicillium species recovered from respiratory tract samples are often considered as inhaled contaminants in the clinical laboratory. However, we report here a case of fungal maxillary sinusitis due to Penicillium roqueforti diagnosed in a 40-year-old female, a teacher, complaining of moderate pain for months in the maxillary sinus and chronic posterior rhinorrhea. CT scanner and MRI enabled a preliminary diagnosis of left maxillary fungus ball-type sinusitis with calcified material seen on CT and marked very low signal in T2 weighted images seen on MRI. Anatomopathological and mycological examination of sinusal content showed septate hyphae. Direct sequencing of the sinusal content revealed P. roqueforti. P. roqueforti has been traditionally used in France for more than 200 years for cheese ripening. However, to our knowledge, this ascomycetous fungus has very rarely been associated in the literature with human disease. P. roqueforti is associated only with cheese worker's lung, a hypersensitivity pneumonitis affecting employees in blue cheese factories. Other species in the Penicillium genus are reported to cause various disorders such as invasive infection, superficial infection or allergic diseases. P. roqueforti has never previously been reported as a cause of human infection. Thus, we report the first case of fungus ball due to P. roqueforti in an immunocompetent patient.
Asunto(s)
Sinusitis Maxilar/diagnóstico , Sinusitis Maxilar/patología , Micosis/diagnóstico , Micosis/patología , Penicillium/aislamiento & purificación , Adulto , Femenino , Francia , Humanos , Imagen por Resonancia Magnética , Seno Maxilar/diagnóstico por imagen , Sinusitis Maxilar/microbiología , Micosis/microbiología , Penicillium/clasificación , Penicillium/genética , Análisis de Secuencia de ADN , Tomografía Computarizada por Rayos XRESUMEN
Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry has emerged as a reliable technique to identify molds involved in human diseases, including dermatophytes, provided that exhaustive reference databases are available. This study assessed an online identification application based on original algorithms and an extensive in-house reference database comprising 11,851 spectra (938 fungal species and 246 fungal genera). Validation criteria were established using an initial panel of 422 molds, including dermatophytes, previously identified via DNA sequencing (126 species). The application was further assessed using a separate panel of 501 cultured clinical isolates (88 mold taxa including dermatophytes) derived from five hospital laboratories. A total of 438 (87.35%) isolates were correctly identified at the species level, while 26 (5.22%) were assigned to the correct genus but the wrong species and 37 (7.43%) were not identified, since the defined threshold of 20 was not reached. The use of the Bruker Daltonics database included in the MALDI Biotyper software resulted in a much higher rate of unidentified isolates (39.76 and 74.30% using the score thresholds 1.7 and 2.0, respectively). Moreover, the identification delay of the online application remained compatible with real-time online queries (0.15 s per spectrum), and the application was faster than identifications using the MALDI Biotyper software. This is the first study to assess an online identification system based on MALDI-TOF spectrum analysis. We have successfully applied this approach to identify molds, including dermatophytes, for which diversity is insufficiently represented in commercial databases. This free-access application is available to medical mycologists to improve fungal identification.