RESUMEN
For postnatal diagnosis of congenital toxoplasmosis (CT), the gold standard for the detection of anti-Toxoplasma IgM in newborns relies on the immunosorbent agglutination assay (ISAGA), which is manufactured from whole Toxoplasma parasites that become difficult to maintain. For IgG, only the Platelia assay provides a validated assay for cord blood according to the manufacturer, allowing its use in this context. We compared the analytical performance of four commercialized automated assays, Platelia, Abbott, Vidas, and Liaison, for the detection of IgG and IgM in the cord blood or peripheral blood of newborns from women infected during pregnancy. The assays were performed on samples from 509 newborns, collected from the university hospitals of Montpellier, Nîmes, and Toulouse. For IgM, the four assays appeared to be sufficiently informative to be used for congenital toxoplasmosis diagnosis (area under the curve [AUC] > 0.8, receiver operating characteristic [ROC] analysis), with Platelia showing the best performance, similar to ISAGA with regard to accuracy (83%). For the Vidas (76%), Abbott (75%), and Liaison (74%) assays, the accuracy was significantly lower. Maternal treatment significantly decreased the sensitivity of all the assays. For IgG, the four evaluated assays showed a sensitivity of over 90%, with Abbott (95%) and Liaison (94%), exhibiting a significantly higher sensitivity than Platelia (90%). Furthermore, Abbott showed its superiority in the cases of maternal infection during the third trimester. In the context of the newborns of mothers infected by Toxoplasma gondii during pregnancy, to ensure efficient care, Platelia and Abbott seemed to be the most suitable reference tests for the detection of IgM for the former and IgG for the latter.
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Complicaciones Parasitarias del Embarazo , Toxoplasma , Toxoplasmosis Congénita , Toxoplasmosis , Anticuerpos Antiprotozoarios , Femenino , Humanos , Inmunoglobulina G , Inmunoglobulina M , Recién Nacido , Embarazo , Complicaciones Parasitarias del Embarazo/diagnóstico , Toxoplasmosis/diagnóstico , Toxoplasmosis Congénita/diagnósticoRESUMEN
The diagnostic accuracy of a commercial Toxoplasma gondii IgA antibody enzyme-linked immunosorbent assay (ELISA) was evaluated in the context of routine practice on 289 newborns with congenital toxoplasmosis (CT) and 220 healthy controls. The performance of this assay was compared to that of the current gold-standard test for anti-Toxoplasma IgM detection, an immunosorbent agglutination assay (ISAGA). IgM and IgA sensitivity and specificity were assessed in cord and postnatal samples. The sensitivity of IgA detection by ELISA on all serum and peripheral blood samples was 60.56% and 56.52%, respectively, which is low compared with the sensitivity of IgM detection by ISAGA (73.26% on serum samples, 82.35% on peripheral blood). Adding the T. gondii IgA antibody ELISA to the diagnostic panel did not significantly increase the overall performance of the serological diagnosis based on IgM detection.
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Toxoplasma , Toxoplasmosis Congénita , Toxoplasmosis , Anticuerpos Antiprotozoarios , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina A , Inmunoglobulina M , Recién Nacido , Toxoplasmosis/diagnóstico , Toxoplasmosis Congénita/diagnósticoRESUMEN
BACKGROUND: Moulds are often wrongly considered contaminants, not very sensitive to conventional antifungal treatments, but they may cause ungual hyphomycosis, particularly Aspergillus. Due to the lack of precise diagnostic criteria, their real impact is underestimated. OBJECTIVES: Retrospective descriptive analysis of all ungual hyphomycosis cases diagnosed at Montpellier Hospital from 1991 to 2019 to: (i) determine the incidence of onychomycosis by pseudo-dermatophytes and moulds; (ii) perform an epidemiological analysis of nail aspergillosis; and (iii) provide simple criteria for mould involvement in onychopathy. PATIENTS/METHODS: Data concerning 4053 patients were collected: age, sex, onychomycosis location, direct examination results, species(s) identified and fungal co-infections. Moreover, clinical data of patients with nail aspergillosis were analysed to identify potential contributing factors, and the classical criteria for mould involvement in onychopathy were critically reviewed. RESULTS: A pseudo-dermatophyte or a mould was involved in nail colonisation in 17.25% of patients (men/women ratio: 0.70; mean age: 53.1 years). The identified hyphomycetes belonged mainly to the genera Fusarium (45.68%), Scopulariopsis (30.23%) and Aspergillus (16.94%). Analysis of the clinical reports of 102 patients with ungual aspergillosis (men/women ratio: 0.67; mean age: 56.3 years) identified cardiovascular (43.9%), endocrine (25.8%), cancer (19.7%) and skin (18.2%) diseases as contributing factors. CONCLUSIONS: The adoption of simple and reliable criteria (ie, characteristic filaments on direct microscopic examination after periodic acid-Schiff staining, growth at seeding points in culture) allows determining the formal involvement of a mould in chronic onychopathies and avoiding possible side effects and costs of empirical or inappropriate and repetitive treatments.
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Aspergilosis , Enfermedades de la Uña , Onicomicosis , Aspergilosis/diagnóstico , Aspergilosis/epidemiología , Aspergillus , Femenino , Francia/epidemiología , Hongos , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Uña/epidemiología , Enfermedades de la Uña/microbiología , Onicomicosis/diagnóstico , Onicomicosis/epidemiología , Estudios RetrospectivosRESUMEN
OBJECTIVES: Aspergillus cryptic species are increasingly recognised causes of Aspergillus diseases, including life-threatening invasive aspergillosis (IA). However, as their accurate identification remains challenging in a routine practice, few is known from a clinical and epidemiological perspective. Recently, the MSI application has emerged as a powerful tool for the detection and identification of Aspergillus cryptic species. We aimed to use to the network of users of the MSI application to conduct a multicentre prospective screening of Aspergillus cryptic species-related IA and analyse their epidemiological, clinical and mycological characteristics. METHODS: Over a 27-month period, the clinical involvement of 369 Aspergillus cryptic isolates, from 13 French and Danish MSI application users, was prospectively analysed. Species identification was confirmed by DNA-sequencing and antifungal susceptibility testing was performed using EUCAST reference method. Fifty-one A fumigatus sensu stricto invasive cases were also analysed. RESULTS: Fifteen cryptic isolates were responsible of IA. Eight species were involved, including 5 cases related to the species A sublatus. These species showed high rate of in vitro low susceptibility to antifungal drugs. In comparison with A fumigatus sensu stricto invasive cases, pre-exposure to azole drugs was significantly associated with cryptic IA (P = .02). DISCUSSION: This study brings new insights in cryptic species related IA and underlines the importance to identify accurately at the species level these Aspergillus isolates. The increasing use of antifungal drugs might lead in the future to an epidemiologic shift with an emergence of resistant isolates involved in IA.
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Aspergillus/clasificación , Aspergilosis Pulmonar Invasiva/microbiología , Adulto , Anciano , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Farmacorresistencia Fúngica , Femenino , Francia/epidemiología , Humanos , Aspergilosis Pulmonar Invasiva/epidemiología , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Rapid diagnostic tests (RDTs) detecting the histidine-rich protein 2 (PfHRP2) have a central position for the management of Plasmodium falciparum infections. Yet, variable detection of certain targeted motifs, low parasitaemia, but also deletion of pfhrp2 gene or its homologue pfhrp3, may result in false-negative RDT leading to misdiagnosis and delayed treatment. This study aimed at investigating the prevalence, and understanding the possible causes, of P. falciparum RDT-negative infections at Montpellier Academic Hospital, France. METHODS: The prevalence of falsely-negative RDT results reported before and after the introduction of a loop-mediated isothermal amplification (LAMP) assay, as part as the malaria screening strategy in January 2017, was analysed. Negative P. falciparum RDT infections were screened for pfhrp2 or pfhrp3 deletion; and exons 2 were sequenced to show a putative genetic diversity impairing PfHRP2 detection. RESULTS: The overall prevalence of P. falciparum negative RDTs from January 2006 to December 2018 was low (3/446). Whereas no cases were reported from 2006 to 2016 (0/373), period during which the malaria diagnostic screen was based on microscopy and RDT, prevalence increased up to 4.1% (3/73) between 2017 and 2018, when molecular detection was implemented for primary screening. Neither pfhrp2/3 deletion nor major variation in the frequency of repetitive epitopes could explain these false-negative RDT results. CONCLUSION: This paper demonstrates the presence of pfhrp2 and pfhrp3 genes in three P. falciparum RDT-negative infections and reviews the possible reasons for non-detection of HRP2/3 antigens in a non-endemic setting. It highlights the emergence of falsely negative rapid diagnostic tests in a non-endemic setting and draws attention on the risk of missing malaria cases with low parasitaemia infections using the RDT plus microscopy-based strategy currently recommended by French authorities. The relevance of a novel diagnostic scheme based upon a LAMP assay is discussed.
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Antígenos de Protozoos/análisis , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Plasmodium falciparum/aislamiento & purificación , Proteínas Protozoarias/análisis , Reacciones Falso Negativas , Francia/epidemiología , Malaria Falciparum/epidemiología , Plasmodium falciparum/genética , PrevalenciaRESUMEN
The taxonomy of Aspergillus species has recently been revolutionized with the introduction of cryptic species and section concepts. However, their species-level identification in routine laboratories remains a challenge. The aim of this study was to prospectively assess the identification accuracy of cryptic species of Aspergillus in various laboratories using the mass spectrometry identification (MSI) platform, an independent and freely accessible online mass spectrometry database. Over a 12-month period, when a select set of MSI users identified cryptic species, they were contacted and requested to send the isolates to our laboratory for sequence-based identification. Sequence and MSI identification results were then compared. During the study period, 5108 Aspergillus isolates were identified using MSI including 1477 (28.9%) cryptic species. A total of 245 isolates that corresponded to 56 cryptic species and 13 sections were randomly selected for DNA sequencing confirmation. Agreement between the two methods was 99.6% at the section level and 66.1% at the species level. However, almost all discrepancies (72/83, 86.7%) were misidentifications between closely related cryptic species belonging to the same section. Fifty-one isolates from noncryptic species were also identified, thus yielding 100% and 92.2% agreement at the section and species level, respectively. Although the MSI fungus database is a reliable tool to identify Aspergillus at the section level, the database still requires adjustment to correctly identify rare or cryptic species at the species level. Nevertheless, the application properly differentiated between cryptic and sensu stricto species in the same section, thus alerting on possible specific isolate characteristics.
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Aspergillus/química , Aspergillus/clasificación , Bases de Datos Factuales , Internet , Técnicas Microbiológicas/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , HumanosRESUMEN
Human leishmaniases are widespread diseases with different clinical forms caused by about 20 species within the Leishmania genus. Leishmania species identification is relevant for therapeutic management and prognosis, especially for cutaneous and mucocutaneous forms. Several methods are available to identify Leishmania species from culture, but they have not been standardized for the majority of the currently described species, with the exception of multilocus enzyme electrophoresis. Moreover, these techniques are expensive, time-consuming, and not available in all laboratories. Within the last decade, mass spectrometry (MS) has been adapted for the identification of microorganisms, including Leishmania However, no commercial reference mass-spectral database is available. In this study, a reference mass-spectral library (MSL) for Leishmania isolates, accessible through a free Web-based application (mass-spectral identification [MSI]), was constructed and tested. It includes mass-spectral data for 33 different Leishmania species, including species that infect humans, animals, and phlebotomine vectors. Four laboratories on two continents evaluated the performance of MSI using 268 samples, 231 of which were Leishmania strains. All Leishmania strains, but one, were correctly identified at least to the complex level. A risk of species misidentification within the Leishmania donovani, L. guyanensis, and L. braziliensis complexes was observed, as previously reported for other techniques. The tested application was reliable, with identification results being comparable to those obtained with reference methods but with a more favorable cost-efficiency ratio. This free online identification system relies on a scalable database and can be implemented directly in users' computers.
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Bases de Datos Factuales , Leishmania/clasificación , Leishmaniasis/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Biblioteca de Genes , Humanos , Internet , Leishmania/genética , Leishmaniasis/parasitologíaRESUMEN
Monitoring fungal ecology and resistance to antifungal agents within intensive care units (ICU) is essential for the management of invasive fungal infections. Therefore, a retrospective descriptive study was carried in the ICU of Nimes University Hospital, France, from 2007 to 2016. As the majority of invasive fungal infections in ICU are caused by Candida species, the study objectives were to describe Candida species distribution, to assess candidaemia incidence and to monitor the antifungal drug susceptibility of Candida isolates and the consumption of antifungal agents. Among the recorded invasive Candida infections (n=244), 43% were intra-abdominal and 22% bloodstream infections. Candida albicans was the most frequent species (55.8%), followed by Candida glabrata (14.1%), Candida tropicalis (10%), Candida parapsilosis (8%) and Candida krusei (5.3%). Candidaemia incidence was 4.49 per 1000 admissions. The mean consumption of antifungal agents was of 170.5 defined daily doses (DDD) for 1000 hospital days (HD) per year. Changes in antifungal drug consumption were observed, with an increased use of echinocandins (from 17.96 DDD/1000 HD in 2007 to 48.76 DDD/1000 HD in 2016), and the total treatment cost tripled during the study period. No significant change in fungal ecology or in the emergence of resistant species was observed; indeed, only 1.1% of isolates presented an unusual resistance to antifungal agents.
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Antifúngicos/uso terapéutico , Candida/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Candidiasis/epidemiología , Candida/clasificación , Candida/genética , Candida/aislamiento & purificación , Candidiasis/microbiología , Farmacorresistencia Fúngica , Francia/epidemiología , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Pruebas de Sensibilidad Microbiana , Estudios RetrospectivosRESUMEN
Nucleoporins are evolutionary conserved proteins mainly involved in the constitution of the nuclear pores and trafficking between the nucleus and cytoplasm, but are also increasingly viewed as main actors in chromatin dynamics and intra-nuclear mitotic events. Here, we determined the cellular localization of the nucleoporin Mlp2 in the 'divergent' eukaryotes Leishmania major and Trypanosoma brucei. In both protozoa, Mlp2 displayed an atypical localization for a nucleoporin, essentially intranuclear, and preferentially in the periphery of the nucleolus during interphase; moreover, it relocated at the mitotic spindle poles during mitosis. In T. brucei, where most centromeres have been identified, TbMlp2 was found adjacent to the centromeric sequences, as well as to a recently described unconventional kinetochore protein, in the periphery of the nucleolus, during interphase and from the end of anaphase onwards. TbMlp2 and the centromeres/kinetochores exhibited a differential migration towards the poles during mitosis. RNAi knockdown of TbMlp2 disrupted the mitotic distribution of chromosomes, leading to a surprisingly well-tolerated aneuploidy. In addition, diploidy was restored in a complementation assay where LmMlp2, the orthologue of TbMlp2 in Leishmania, was expressed in TbMlp2-RNAi-knockdown parasites. Taken together, our results demonstrate that Mlp2 is involved in the distribution of chromosomes during mitosis in trypanosomatids.
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Cromosomas , Leishmania major/genética , Mitosis/genética , Proteínas de Complejo Poro Nuclear/fisiología , Proteínas Protozoarias/fisiología , Trypanosoma brucei brucei/genética , Transporte Biológico , Centrómero/química , Centrómero/metabolismo , Cromosomas/química , Proteínas de Complejo Poro Nuclear/análisis , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas Protozoarias/análisis , Proteínas Protozoarias/metabolismoRESUMEN
Pneumonia due to Pneumocystis jirovecii (PCP) is a frequent infection among HIV-positive or other immunocompromised patients. In the past several years, PCR on pulmonary samples has become an essential element for the laboratory diagnosis of PCP. Nevertheless, very few comparative studies of available PCR assays have been published. In this work, we evaluated the concordance between four real-time PCR assays, including three commercial kits, AmpliSens, MycAssay, and Bio-Evolution PCR, and an in-house PCR (J. Fillaux et al. 2008, J Microbiol Methods 75:258-261, doi:http://dx.doi.org/10.1016/j.mimet.2008.06.009), on 148 pulmonary samples. The results showed concordance rates ranging from 81.6% to 96.6% (kappa, 0.64 to 0.93). Concordance was excellent between three assays: the in-house assay, AmpliSens, and the MycAssay PCR (kappa, >0.8). The performances of these PCR assays were also evaluated according to the classification of the probability of PCP (proven, probable, possible, or no final diagnosis of PCP) based on clinical and radiological signs as well as on the direct examination of bronchoalveolar lavage samples. In the proven PCP category, Pneumocystis jirovecii DNA was detected with all four assays. In the probable PCP category, the in-house PCR, AmpliSens, and the MycAssay PCR were positive for all samples, while the Bio-Evolution PCR failed to detect Pneumocystis jirovecii DNA in two samples. In the possible PCP category, the percentage of positive samples according to PCR varied from 54.5% to 86.4%. Detection of colonized patients is discussed. Finally, among the four evaluated PCR assays, one was not suitable for colonization detection but showed good performance in the proven and probable PCP groups. For the three other assays, performances were excellent and allowed detection of a very low fungal burden.
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Técnicas de Diagnóstico Molecular/métodos , Pneumocystis carinii/aislamiento & purificación , Neumonía por Pneumocystis/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: Blastocystis sp. is the most common intestinal parasite of humans. Despite its potential public health impact, epidemiological data regarding the prevalence and molecular subtype distribution of Blastocystis sp. in Europe are rarely reported. Therefore, the first multi-center epidemiological survey performed in Europe was conducted in France to diagnose and subtype Blastocystis sp. and to identify risk factors for infection. METHODS: Stool samples from 788 patients were collected either in summer or winter in 11 hospitals throughout France together with patient data. All stool samples were tested for the presence of Blastocystis sp. by quantitative PCR targeting the SSU rDNA gene. Positive samples were sequenced to determine the distribution of the subtypes in our cohort. Statistical analyses were performed to identify potential risk factors for infection. RESULTS: Using quantitative PCR, the overall prevalence of Blastocystis sp. was shown to reach 18.1 %. The prevalence was significantly higher in summer (23.2 %) than in winter (13.7 %). Travellers or subjects infected with other enteric parasites were significantly more infected by Blastocystis sp. than non-travellers or subjects free of other enteric parasites, respectively. Different age-related epidemiological patterns were also highlighted from our data. The prevalence of Blastocystis sp. was not significantly higher in patients with digestive symptoms or diagnosed with chronic bowel diseases. Among symptomatic patients, Blastocystis sp. infection was significantly associated with abdominal pain. Gender, socioeconomic status, and immune status were not identified as potential risk factors associated with infection. Among a total of 141 subtyped isolates, subtype 3 was predominant (43.3 %), followed by subtype 1 and subtype 4 (20 %), subtype 2 (12.8 %), subtype 6 and subtype 7 (2.1 %). No association between ST and clinical symptoms was statistically evidenced. CONCLUSIONS: A high prevalence of Blastocystis sp. infection was found in our French patient population. Seasonal impact on the prevalence of Blastocystis sp. was highlighted and recent travels and age were identified as main risk factors for infection. Most cases were caused by subtypes 1 to 4, with a predominance of subtype 3. Large variations in both prevalence and ST distribution between hospitals were also observed, suggesting distinct reservoirs and transmission sources of the parasite.
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Infecciones por Blastocystis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Blastocystis/clasificación , Blastocystis/aislamiento & purificación , Infecciones por Blastocystis/diagnóstico , Niño , Preescolar , Estudios Transversales , Heces/parasitología , Femenino , Francia , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto JovenRESUMEN
Leishmania are unicellular eukaryotes that have many markedly original molecular features compared with other uni- or multicellular eukaryotes like yeasts or mammals. Genome plasticity in this parasite has been the subject of many publications, and has been associated with drug resistance or adaptability. Aneuploidy has been suspected by several authors and it is now confirmed using state-of-the-art technologies such as high-throughput DNA sequencing. The analysis of genome contents at the single cell level using fluorescence in situ hybridization (FISH) has brought a new light on the genome organization: within a cell population, every chromosome, in every cell, may be present in at least two ploidy states (being either monosomic, disomic or trisomic), and the chromosomal content varies greatly from cell to cell, thus generating a constitutive intra-strain genomic heterogeneity, here termed 'mosaic aneuploidy'. Mosaic aneuploidy deeply affects the genetics of these organisms, leading, for example, to an extreme degree of intra-strain genomic diversity, as well as to a clearance of heterozygous cells in the population without however affecting genetic heterogeneity. Second, mosaic aneuploidy might be considered as a powerful strategy evolved by the parasite for adapting to modifications of environment conditions as well as for the emergence of drug resistance. On the whole, mosaic aneuploidy may be considered as a novel mechanism for generating phenotypic diversity driven by genomic plasticity.
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Aneuploidia , Genoma de Protozoos , Leishmania/genética , Adaptación Biológica , Evolución Molecular , Heterogeneidad Genética , Tamaño del Genoma , Inestabilidad GenómicaRESUMEN
This study aimed to assess the antileishmanial activity of biomolecules obtained from Olea europaea L. leaves and twigs recovered from eight Tunisian cultivars. The extraction was first carried out with 80% methanol, and then the obtained extract was fractionated using three solvents of increasing polarity: cyclohexane (CHX), dichloromethane (DCM) and ethyl acetate (EtOAc). The antileishmanial activity was determined against leishmanial strains responsible for cutaneous, visceral, and mucocutaneous leishmaniasis. The cyclohexane fraction of the leaves of cv. Chemlali from the region of Sidi-Bouzid exhibited the strongest leishmanicidal activity against all the tested leishmanial strains. The inhibition concentrations (IC50) were 16.5, 14.5, and 7.4 µg mL-1 for Leishmania mexicana (cutaneous), Leishmania braziliensis (mucocutaneous), and Leishmania donovani (visceral), respectively. Interestingly, low cytotoxicity was observed on THP-1 cells with selective indexes (SI) ranging from 22.8 to 50.5. HPLC-HRMS and full-house NMR analysis allowed the identification of three triterpenic compounds, oleanolic acid (IC50 = 64.1 µg mL-1), erythrodiol (IC50 = 52.0 µg mL-1), and uvaol (IC50 = 53.8 µg mL-1). Antileishmanial activity of uvaol and oleanolic acid has been previously reported. However, this work constitutes the first report of the antileishmanial activity of erythrodiol which showed combinatorial interaction with uvaol (IC50 = 26.1 µg mL-1) against Leishmania tropica. The mixture of the three compounds, as major ones, exhibited an enhanced activity against Leishmania tropica (IC50 = 16.3 µg mL-1) compared to erythrodiol alone or the combination of uvaol and erythrodiol. This finding is of great importance and needs further investigation. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03825-3.
RESUMEN
OBJECTIVES: To determine the epidemiological cut-off values (ECVs) of ten antifungal agents in a wide range of yeasts and Aspergillus spp. using gradient concentration strips. METHODS: The minimum inhibitory concentrations for amphotericin B, anidulafungin, caspofungin, micafungin, flucytosine, fluconazole, itraconazole, isavuconazole, posaconazole, and voriconazole, determined with gradient concentration strips at 35 French microbiology laboratories between 2002 and 2020, were retrospectively collected. Then, the ECVs were calculated using the iterative method and a cut-off value of 97.5%. RESULTS: Minimum inhibitory concentrations were available for 17 653 clinical isolates. In total, 48 ECVs (including 32 new ECVs) were determined: 29 ECVs for frequent yeast species (e.g. Candida albicans and itraconazole/flucytosine, and Candida glabrata species complex [SC] and flucytosine) and rare yeast species (e.g. Candida dubliniensis, Candida inconspicua, Saccharomyces cerevisiae, and Cryptococcus neoformans) and 19 ECVs for Aspergillusflavus SC, Aspergillusfumigatus SC, Aspergillusnidulans SC, Aspergillusniger SC, and Aspergillusterreus SC. CONCLUSIONS: These ECVs can be added to the already available gradient concentration strip-specific ECVs to facilitate minimum inhibitory concentration interpretation and streamline the identification of nonwild type isolates.
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Antifúngicos , Itraconazol , Humanos , Antifúngicos/farmacología , Itraconazol/farmacología , Flucitosina , Saccharomyces cerevisiae , Estudios Retrospectivos , Filogenia , Fluconazol/farmacología , Aspergillus , Pruebas de Sensibilidad Microbiana , Farmacorresistencia FúngicaRESUMEN
The protozoan parasite Leishmania is generally considered to be diploid, although a few chromosomes have been described as aneuploid. Using fluorescence in situ hybridization (FISH), we determined the number of homologous chromosomes per individual cell in L. major (i) during interphase and (ii) during mitosis. We show that, in Leishmania, aneuploidy appears to be the rule, as it affects all the chromosomes that we studied. Moreover, every chromosome was observed in at least two ploidy states, among monosomic, disomic or trisomic, in the cell population. This variable chromosomal ploidy among individual cells generates intra-strain heterogeneity, here precisely chromosomal mosaicism. We also show that this mosaicism, hence chromosome ploidy distribution, is variable among clones and strains. Finally, when we examined dividing nuclei, we found a surprisingly high rate of asymmetric chromosome allotments, showing that the transmission of genetic material during mitosis is highly unstable in this 'divergent' eukaryote: this leads to continual generation of chromosomal mosaicism. Using these results, we propose a model for the occurrence and persistence of this mosaicism. We discuss the implications of this additional unique feature of Leishmania for its biology and genetics, in particular as a novel genetic mechanism to generate phenotypic variability from genomic plasticity.
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Aneuploidia , Aberraciones Cromosómicas , Leishmania major/citología , Leishmania major/genética , Segregación Cromosómica , Hibridación Fluorescente in Situ , Leishmania major/crecimiento & desarrollo , Mitosis , Parasitología/métodosRESUMEN
BACKGROUND: Flow cytometry and cell sorting are powerful tools enabling the selection of particular cell types within heterogeneous cell mixtures. These techniques, combined with whole genome amplification that non-specifically amplify small amounts of starting DNA, offer exciting new opportunities for the study of malaria genetics. Among them, two are tested in this paper: (1) single cell genotyping and (2) parasite DNA purification for subsequent whole genome sequencing using shotgun technologies. METHODS: The method described allows isolation of Plasmodium falciparum trophozoites, genotyping and whole genome sequencing from the blood of infected patients. For trophozoite isolation, parasite and host nuclei are stained using propidium iodide (PI) followed by flow cytometry and cell sorting to separate trophozoites from host cells. Before genotyping or sequencing, whole genome amplification is used to increase the amount of DNA within sorted samples. The method has been specifically designed to deal with frozen blood samples. RESULTS AND CONCLUSION: The results demonstrate that single trophozoite genotyping is possible and that cell sorting can be successfully applied to reduce the contaminating host DNA for subsequent whole genome sequencing of parasites extracted from infected blood samples.
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Citometría de Flujo/métodos , Parasitología/métodos , Plasmodium falciparum/aislamiento & purificación , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Propidio/metabolismo , Coloración y Etiquetado/métodos , TrofozoítosRESUMEN
OBJECTIVE: Post kala-azar dermal leishmaniasis (PKDL) is a rare complication of visceral leishmaniasis. We aimed at reporting PKDL cases in people living with HIV (PLHIV) and compare their characteristics based on whether PKDL occurred in the context of immune recovery under antiretroviral therapy (ART) or not. DESIGN: National survey and literature review. METHODS: We called for observations in France in October 2020 and performed a literature review from PubMed (Medline) and Web of Science up to December 2020. Two groups of patients were defined based on whether PKDL occurred in the context of immune recovery under ART (group 1) or not (group 2), and compared. RESULTS: Three PLHIV with PKDL identified in France in the last decade were described and added to 33 cases from the literature. Compared with group 2 (16/36, 44.4%), patients from group 1 (20/36, 55.6%) originated more frequently from Europe (12/20, 60% vs. 2/16, 12.5%; P â=â0.0038), had higher median blood CD4 + cell counts (221/µl vs. 61/µl; P â=â0.0005) and increase under ART (122/µl, interquartile range 73-243 vs. 33/µl, interquartile range 0-53; P â=â0.0044), had less frequently concomitant visceral leishmaniasis (3/20, 15% vs. 8/12, 66.7%; P â=â0.006), and a trend to more frequent ocular involvement (7/20, 35% vs. 1/16, 6.25%; P â=â0.0531). CONCLUSION: In PLHIV, PKDL occurs after a cured episode of visceral leishmaniasis as part of an immune restoration disease under ART, or concomitant to a visceral leishmaniasis relapse in a context of AIDS. For the latter, the denomination 'disseminated cutaneous lesions associated with visceral leishmaniasis' seems more accurate than PKDL.
Asunto(s)
Infecciones por VIH , Leishmaniasis Cutánea , Leishmaniasis Visceral , Europa (Continente) , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Leishmaniasis Cutánea/complicaciones , Leishmaniasis Cutánea/patología , Leishmaniasis Visceral/complicaciones , Leishmaniasis Visceral/epidemiología , RecurrenciaRESUMEN
BACKGROUND: In France, leishmaniasis is endemic in the Mediterranean region, in French Guiana and to a lesser extent, in the French West Indies. This study wanted to provide an updated picture of leishmaniasis epidemiology in metropolitan France and in its overseas territories. METHODOLOGY/PRINCIPAL FINDINGS: Leishmaniasis cases were collected by passive notification to the French National Reference Centre for Leishmaniases (NRCL) in Montpellier from 1998 to 2020 and at the associated Centre in Cayenne (French Guiana) from 2003 to 2020. In metropolitan France, 517 autochthonous leishmaniasis cases, mostly visceral forms due to Leishmania infantum (79%), and 1725 imported cases (French Guiana excluded), mainly cutaneous leishmaniasis from Maghreb, were recorded. A slight decrease of autochthonous cases was observed during the survey period, from 0.48 cases/100,000 inhabitants per year in 1999 (highest value) to 0.1 cases/100,000 inhabitants per year in 2017 (lowest value). Conversely, imported cases increased over time (from 59.7 in the 2000s to 94.5 in the 2010s). In French Guiana, 4126 cutaneous and mucocutaneous leishmaniasis cases were reported from 2003 to 2020. The mean incidence was 103.3 cases per 100,000 inhabitants/year but varied in function of the year (from 198 in 2004 to 54 in 2006). In Guadeloupe and Martinique (French West Indies), only sporadic cases were reported. CONCLUSIONS/SIGNIFICANCE: Because of concerns about disease expansion and outbreaks in other Southern Europe countries, and leishmaniasis monitoring by the NRCL should be continued and associated with a more active surveillance.
Asunto(s)
Leishmania infantum , Leishmaniasis Cutánea , Leishmaniasis Mucocutánea , Humanos , Francia/epidemiología , Indias OccidentalesRESUMEN
Cryptococcosis is the third most common cause of invasive fungal infection in solid organ transplant recipients and cryptococcal meningitis (CM) its main clinical presentation. CM outcomes, as well as its clinical features and radiological characteristics, have not yet been considered on a large scale in the context of kidney transplantation (KT). We performed a nationwide retrospective study of adult patients diagnosed with cryptococcosis after KT between 2002 and 2020 across 30 clinical centers in France. We sought to describe overall and graft survival based on whether KT patients with cryptococcosis developed CM or not. Clinical indicators of CNS involvement and brain radiological characteristics were assessed. Eighty-eight cases of cryptococcosis were diagnosed during the study period, with 61 (69.3%) cases of CM. Mortality was high (32.8%) at 12 months (M12) but not significantly different whether or not patients presented with CM. Baseline hyponatremia and at least one neurological symptom were independently associated with CM (p < 0.001). Positive serum cryptococcal antigen at diagnosis was also significantly associated with CM (p < 0.001). On magnetic resonance imaging (MRI), three patterns of brain injury were identified: parenchymal, meningeal, and vascular lesions. Although CM does not affect graft function directly, it entails a grim prognosis.
RESUMEN
Comprehensive data on emerging invasive fungal infections (EIFIs) in the critically ill are scarce. We conducted a case-control study to characterize EIFIs in patients admitted to a French medical ICU teaching hospital from 2006 to 2019. Among 6900 patients, 26 (4 per 1000) had an EIFI: Mucorales accounted for half, and other isolates were mainly Saprochaete, Fusarium and Scedosporium. EIFIs occurred mostly in patients with immunosuppression and severe critical illness. Antifungal treatments (mainly amphotericin B) were administered to almost all patients, whereas only 19% had surgery. In-ICU, mortality was high (77%) and associated with previous conditions such as hematological malignancy or cancer, malnutrition, chronic kidney disease and occurrence of acute respiratory distress syndrome and/or hepatic dysfunction. Day-90 survival rates, calculated by the Kaplan-Meier method, were similar between patients with EIFIs and a control group of patients with aspergillosis: 20%, 95% CI (9- 45) versus 18%, 95% CI (8- 45) (log-rank: p > 0.99). ICU management of such patients should be assessed on the basis of underlying conditions, reversibility and acute event severity rather than the mold species.