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BACKGROUND: While the serological detection of (1â3)-ß-D-glucan (BDG) can indicate invasive fungal disease (IFD), false positivity occurs. Nevertheless, the presence of BDG can still be recognized by the host's innate immune system and persistent BDG antigenemia, in the absence of IFD, can result in deleterious proinflammatory immune responses. METHODS: During the XXX (INTENSE) study into the preemptive use of micafungin to prevent invasive candidiasis (IC) after abdominal surgery, the serum burden of BDG was determined to aid diagnosis of IC. Data from the INTENSE study were analyzed to determine whether BDG was associated with organ failure and patient mortality, while accounting for the influences of IC and antifungal therapy. RESULTS: A BDG concentration >100 pg/mL was associated with a significantly increased Sequential Organ Failure Assessment score (≤100 pg/mL: 2 vs >100 pg/mL: 5; P < .0001) and increased rates of mortality (≤100 pg/mL: 13.7% vs >100 pg/mL: 39.0%; P = .0002). Multiple (≥2) positive results >100 pg/mL or a BDG concentration increasing >100 pg/mL increased mortality (48.1%). The mortality rate in patients with IC and a BDG concentration >100 pg/mL and ≤100 pg/mL was 42.3% and 25.0%, respectively. The mortality rate in patients without IC but a BDG concentration >100 pg/mL was 37.3%. The use of micafungin did not affect the findings. CONCLUSIONS: The presence of persistent or increasing BDG in the patient's circulation is associated with significant morbidity and mortality after abdominal surgery, irrespective of IC. The potential lack of a specific therapeutic focus has consequences when trying to manage these patients, and when designing clinical trials involving patients where host-associated BDG concentrations may be elevated. CLINICAL TRIALS REGISTRATION: NCT01122368.
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Candidíase Invasiva , beta-Glucanas , Candidíase Invasiva/diagnóstico , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/prevenção & controle , Glucanos , Humanos , Micafungina , Prognóstico , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Fungal coinfection is a recognized complication of respiratory virus infections, increasing morbidity and mortality, but can be readily treated if diagnosed early. An increasing number of small studies describing aspergillosis in coronavirus disease 2019 (COVID-19) patients with severe respiratory distress are being reported, but comprehensive data are lacking. The aim of this study was to determine the incidence, risk factors, and impact of invasive fungal disease in adult COVID-19 patients with severe respiratory distress. METHODS: An evaluation of a national, multicenter, prospective cohort evaluation of an enhanced testing strategy to diagnose invasive fungal disease in COVID-19 intensive care patients. Results were used to generate a mechanism to define aspergillosis in future COVID-19 patients. RESULTS: One-hundred and thirty-five adults (median age: 57, M/F: 2.2/1) were screened. The incidence was 26.7% (14.1% aspergillosis, 12.6% yeast infections). The overall mortality rate was 38%; 53% and 31% in patients with and without fungal disease, respectively (P = .0387). The mortality rate was reduced by the use of antifungal therapy (mortality: 38.5% in patients receiving therapy vs 90% in patients not receiving therapy (P = .008). The use of corticosteroids (P = .007) and history of chronic respiratory disease (P = .05) increased the likelihood of aspergillosis. CONCLUSIONS: Fungal disease occurs frequently in critically ill, mechanically ventilated COVID-19 patients. The survival benefit observed in patients receiving antifungal therapy implies that the proposed diagnostic and defining criteria are appropriate. Screening using a strategic diagnostic approach and antifungal prophylaxis of patients with risk factors will likely enhance the management of COVID-19 patients.
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COVID-19 , Aspergilose Pulmonar Invasiva , Micoses , Adulto , Humanos , Unidades de Terapia Intensiva , Aspergilose Pulmonar Invasiva/diagnóstico , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Aspergilose Pulmonar Invasiva/epidemiologia , Pessoa de Meia-Idade , Micoses/diagnóstico , Micoses/epidemiologia , Estudos Prospectivos , SARS-CoV-2RESUMO
Rationale:Aspergillus infection in patients with suspected ventilator-associated pneumonia remains uncharacterized because of the absence of a disease definition and limited access to sensitive diagnostic tests.Objectives: To estimate the prevalence and outcomes of Aspergillus infection in adults with suspected ventilator-associated pneumonia.Methods: Two prospective UK studies recruited 360 critically ill adults with new or worsening alveolar shadowing on chest X-ray and clinical/hematological parameters supporting suspected ventilator-associated pneumonia. Stored serum and BAL fluid were available from 194 nonneutropenic patients and underwent mycological testing. Patients were categorized as having probable Aspergillus infection using a definition comprising clinical, radiological, and mycological criteria. Mycological criteria included positive histology or microscopy, positive BAL fluid culture, galactomannan optical index of 1 or more in BAL fluid or 0.5 or more in serum.Measurements and Main Results: Of 194 patients evaluated, 24 met the definition of probable Aspergillus infection, giving an estimated prevalence of 12.4% (95% confidence interval, 8.1-17.8). All 24 patients had positive galactomannan in serum (n = 4), BAL fluid (n = 16), or both (n = 4); three patients cultured Aspergillus sp. in BAL fluid. Patients with probable Aspergillus infection had a significantly longer median duration of critical care stay (25.5 vs. 15.5 d, P = 0.02). ICU mortality was numerically higher in this group, although this was not statistically significant (33.3% vs. 22.8%; P = 0.23).Conclusions: The estimated prevalence for probable Aspergillus infection in this geographically dispersed multicenter UK cohort indicates that this condition should be considered when investigating patients with suspected ventilator-associated pneumonia, including patient groups not previously recognized to be at high risk of aspergillosis.
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Aspergillus/isolamento & purificação , Pneumonia Associada à Ventilação Mecânica/diagnóstico por imagem , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Aspergilose Pulmonar/diagnóstico , Aspergilose Pulmonar/epidemiologia , Adulto , Distribuição por Idade , Idoso , Estudos de Coortes , Comorbidade , Cuidados Críticos/métodos , Estado Terminal/terapia , DNA Fúngico/análise , Feminino , Seguimentos , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pneumonia Associada à Ventilação Mecânica/patologia , Reação em Cadeia da Polimerase/métodos , Prevalência , Estudos Prospectivos , Aspergilose Pulmonar/diagnóstico por imagem , Radiografia Torácica/métodos , Medição de Risco , Distribuição por Sexo , Estatísticas não Paramétricas , Reino UnidoRESUMO
The objectives of this study were to evaluate the performance of the recently released IMMY Aspergillus galactomannan enzyme immunoassay (IMMY GM-EIA) when testing serum samples and to identify the optimal galactomannan index (GMI) positivity threshold for the diagnosis of invasive aspergillosis (IA). This was a retrospective case/control study, comprising 175 serum samples obtained from 131 patients, 35 of whom had probable or possible invasive fungal disease (IFD) as categorized using recently revised, internationally accepted definitions. The IMMY GM-EIA was performed following the manufacturer's instructions. Performance parameters were determined and receiver operator characteristic analysis was used to identify an optimal GMI threshold. Concordance with the Bio-Rad Aspergillus Ag assay (Bio Rad GM-EIA) and IMMY sona Aspergillus lateral flow assay was assessed. The median GMIs generated by the IMMY GM-EIA for samples originating from probable IA/IFD cases (n = 31), possible IFD (n = 4), and control patients (n = 100) were 0.61, 0.11, and 0.14, respectively, and were comparable to those of the Bio-Rad GM-EIA (0.70, 0.04, and 0.04, respectively). Overall qualitative observed sample agreement between the IMMY GM-EIA and Bio-Rad GM-EIA was 94.7%, generating a kappa statistic of 0.820. At a GMI positivity threshold of ≥0.5, the IMMY GM-EIA had a sensitivity and specificity of 71% and 98%, respectively. Reducing the threshold to ≥0.27 generated sensitivity and specificity of 90% and 92%, respectively. The IMMY GM-EIA provides a comparable alternative to the Bio-Rad GM-EIA when testing serum samples. Further prospective, multicenter evaluations are required to confirm the optimal threshold and associated clinical performance.
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Aspergilose , Mananas , Antígenos de Fungos , Aspergilose/diagnóstico , Aspergillus , Ensaio de Imunoadsorção Enzimática , Galactose/análogos & derivados , Humanos , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
Management of invasive aspergillosis has been improved by biomarker assays, but limited accessibility and batch testing limit the impact. Lateral flow assays (LFA) are a simple method for use outside specialist centers, provided performance is acceptable. The objective of this study was to determine the performance of the recently released IMMY sona Aspergillus LFA when testing serum samples. The study took the form of a retrospective, anonymous case/control study comprising 179 serum samples from 136 patients with invasive fungal disease, previously documented using recently revised internationally accepted definitions. The LFA was performed following the manufacturer's instructions using a cube reader to generate a galactomannan index (GMI). Performance parameters were determined, and receiver operator characteristic (ROC) analysis was used to identify an optimal threshold. Concordance with the Bio-Rad Aspergillus Ag assay (GM-EIA) was performed. At the recommended positivity threshold (GMI ≥ 0.5), LFA sensitivity and specificity were 96.9% (31/32) and 98% (98/100), respectively. ROC analysis confirmed the optimal threshold and generated an area under the curve of 0.9919. Qualitative agreement between LFA and GM-EIA was 89.0%, generating a Kappa statistic of 0.698, representing good agreement, with most discordance arising due to false-negative GM-EIA samples that were positive by LFA. The median GMI generated by the LFA was significantly greater than that generated by the GM-EIA. The IMMY sona Aspergillus LFA, when used with a cube reader, provides a rapid alternative to the well-established GM-EIA, potentially detecting more GM epitopes and enhancing sensitivity.
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Aspergilose , Mananas , Antígenos de Fungos , Aspergilose/diagnóstico , Aspergillus , Galactose/análogos & derivados , Humanos , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
In patients with hematological malignancies, bronchoalveolar lavage fluid (BALF) specimens are commonly used for the diagnosis of mold infections. However, it is not clear whether the cell pellet (P) or the supernatant fraction (S) of the BALF specimen is optimal for molecular diagnostic testing. Thus, 99 BALF specimens were collected from 96 hematology patients with or without allogeneic hematopoietic stem cell transplant. The cell pellets and supernatants were processed alone and in combination (S/P) for testing by two fungus-specific real-time PCR assays compliant with international recommendations. The results achieved with S/P were revealed to be superior in comparison to those achieved with S and P alone, with the use of each single fraction showing a reduced sensitivity for the detection of Aspergillus DNA (82% and 43% for S and P, respectively). In 57% of the samples, testing of the combination of S and P generated a lower quantification cycle value than testing of S or P alone. Molds would have been missed in 5 and 16 out of 28 samples if only S or P, respectively, was analyzed. No sample was positive by testing of S or P only. Similar results were obtained for the detection of Mucorales DNA in BALF specimens (reduced sensitivity of 67% and 50% for S and P, respectively). Study patients were categorized according to the current European Organization for the Research and Treatment of Cancer/Mycoses Study Group classification for invasive fungal disease (IFD), revealing that 35 patients had proven/probable IFD (36%), 47 patients had possible IFD (49%), and 14 patients had undetermined IFD (15%).
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Aspergillus/isolamento & purificação , Líquido da Lavagem Broncoalveolar/microbiologia , Infecções Fúngicas Invasivas/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Mucorales/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Adulto , Idoso , Idoso de 80 Anos ou mais , Aspergillus/genética , DNA Fúngico/genética , Humanos , Aspergilose Pulmonar Invasiva/diagnóstico , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/normas , Mucorales/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Sensibilidade e Especificidade , Adulto JovemRESUMO
The Dynamiker® Fungus (1-3)-ß-D-Glucan Assay (D-BDG) has recently become available in the Western Hemisphere for the diagnosis of invasive fungal disease (IFD). Evaluations of its performance for Pneumocystis pneumonia (PcP) are limited. A retrospective evaluation of D-BDG diagnosis of PcP was performed (23 PcP cases and 23 controls). Sensitivity and specificity were 87% and 70%, respectively, reducing the positivity threshold to 45 pg/ml increased sensitivity (96%), whereas a threshold of 300 pg/ml increased specificity (96%). The performance of D-BDG for the detection of PcP is comparable to other IFD, but sensitivity is below that required to confidently exclude PcP.
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Testes Diagnósticos de Rotina/métodos , Pneumonia por Pneumocystis/diagnóstico , Testes Diagnósticos de Rotina/normas , Polissacarídeos Fúngicos/sangue , Humanos , Pneumocystis carinii/química , Pneumonia por Pneumocystis/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade , beta-Glucanas/sangueRESUMO
With the proposal to include Aspergillus PCR in the revised European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) definitions for fungal disease, commercially manufactured assays may be required to provide standardization and accessibility. The PathoNostics AsperGenius assay represents one such test that has the ability to detect a range of Aspergillus species as well as azole resistance in Aspergillus fumigatus Its performance has been validated on bronchoalveolar lavage (BAL) fluid and serum specimens, but recent evidence suggests that testing of plasma may have enhanced sensitivity over that with serum. We decided to evaluate the analytical and clinical performances of the PathoNostics AsperGenius assay for testing of plasma. For the analytical evaluations, plasma was spiked with various concentrations of Aspergillus genomic DNA before extraction following international recommendations, using two automated platforms. For the clinical study, 211 samples from 10 proven/probable invasive aspergillosis (IA) and 2 possible IA cases and 27 controls were tested. The limits of detection for testing of DNA extracted using the bioMérieux EasyMag and Qiagen EZ1 extractors were 5 and 10 genomes/0.5-ml sample, respectively. In the clinical study, true positivity was significantly greater than false positivity (P < 0.0001). The sensitivity and specificity obtained using a single positive result as significant were 80% and 77.8%, respectively. If multiple samples were required to be positive, specificity was increased to 100%, albeit sensitivity was reduced to 50%. The AsperGenius assay provided good clinical performance, but the predicted improvement of testing with plasma was not seen, possibly as a result of target degradation attributed to sample storage. Prospective testing is required to determine the clinical utility of this assay, particularly for the diagnosis of azole-resistant disease.
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Antifúngicos/farmacologia , Aspergillus/isolamento & purificação , Azóis/farmacologia , Farmacorresistência Bacteriana , Aspergilose Pulmonar Invasiva/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Plasma/microbiologia , Adolescente , Adulto , Idoso , Aspergillus/efeitos dos fármacos , Automação Laboratorial/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Invasive fungal disease (IFD) can be caused by a range of pathogens. Conventional diagnosis has the capacity to detect most causes of IFD, but poor performance limits impact. The introduction of non-culture diagnostics, including the detection of (1-3)-ß-D-Glucan (BDG), has shown promising performance for the detection of IFD in variety of clinical settings. Recently, the Dynamiker® Fungus (1-3)-ß-D-Glucan assay (D-BDG) was released as an IFD diagnostic test. This article describes an evaluation of the D-BDG assay for the diagnosis of invasive aspergillosis (IA), invasive candidiasis (IC) and Pneumocystis pneumonia (PCP) across several high-risk patient cohorts and provides comparative data with the Associates of Cape Cod Fungitell® and BioRad Platelia™ Aspergillus Ag (GM) assays. There were 163 serum samples from 121 patients tested, from 21 probable IA cases, 28 proven IC cases, six probable PCP cases, one probable IFD case, 14 possible IFD cases and 64 control patients. For proven/probable IFD the mean BDG concentration was 209pg/ml, significantly greater than the control population (73pg/ml; P: <.0001). The sensitivity, specificity, and diagnostic odds ratio for proven/probable IFD was 81.4%, 78.1%, and 15.5, respectively. Significant BDG false positivity (9/13) was associated post abdominal surgery. D-BDG showed fair and good agreement with the Fungitell®, and GM assays, respectively. In conclusion, the D-BDG provides a useful adjunct test to aid the diagnosis of IFD, with technical flexibility that will assist laboratories processing low sample numbers. Further, large scale, prospective evaluation is required to confirm the clinical validity and determine clinical utility.
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Aspergilose/diagnóstico , Candidíase Invasiva/diagnóstico , Testes Diagnósticos de Rotina/normas , Pneumonia por Pneumocystis/diagnóstico , Aspergilose/sangue , Candidíase Invasiva/sangue , Feminino , Polissacarídeos Fúngicos/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia por Pneumocystis/sangue , Sensibilidade e Especificidade , beta-Glucanas/sangueRESUMO
The commercially developed PathoNostics AsperGenius species assay is a multiplex real-time PCR capable of detecting aspergillosis and genetic markers associated with azole resistance. The assay is validated for testing bronchoalveolar lavage fluids, replacing the requirement for culture and benefiting patient management. Application of this assay to less invasive, easily obtainable samples (e.g., serum) might be advantageous. The aim of this study was to determine the analytical and clinical performance of the AsperGenius species and resistance assays for testing serum samples. For the analytical evaluations, serum samples were spiked with various concentrations of Aspergillus genomic DNA for extraction, following international recommendations. For the clinical study, 124 DNA extracts from 14 proven/probable invasive aspergillosis (IA) cases, 2 possible IA cases, and 33 controls were tested. The resistance assay was performed on Aspergillus fumigatus PCR-positive samples when a sufficient fungal burden was evident. The limits of detection of the species and resistance assays for A. fumigatus DNA were 10 and ≥75 genomes/sample, respectively. Nonreproducible detection at lower burdens was achievable for all markers. With a positivity threshold of 39 cycles, the sensitivity and specificity of the species assay were 78.6% and 100%, respectively. For 7 IA cases, at least one genetic region potentially associated with azole resistance was successfully amplified, although no resistance markers were detected in this small cohort. The AsperGenius assay provides good clinical performance with the added ability to detect azole resistance directly from noninvasive samples. While the available burden will limit application, it remains a significant advancement in the diagnosis and management of aspergillosis.
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Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/isolamento & purificação , Azóis/farmacologia , Farmacorresistência Fúngica , Aspergilose Pulmonar Invasiva/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Soro/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aspergillus fumigatus/genética , DNA Fúngico/genética , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND: The use of the PCR to aid in the diagnosis of Pneumocystis pneumonia (PcP) has demonstrated excellent clinical performance, as evidenced through various systematic reviews and meta-analyses, yet there are concerns over the interpretation of positive results due to the potential presence of Pneumocystis colonization of the airways. While this can be overcome by applying designated positivity thresholds to PCR testing, the shear number of assays described limits the development of a universal threshold. Commercial assays provide the opportunity to overcome this problem, provided satisfactory performance is determined through large-scale, multi-centre evaluations. METHODS: Retrospective case/control and consecutive cohort performance evaluations of the OLM PneumID real-time PCR assay were performed on DNA eluates from a range of samples sent from patients where "in-house" PCR had been performed as part of routine diagnostic testing. The clinical performance of the PneumID assay was determined before including it in a diagnostic algorithm to provide the probability of PcP (dependent on diagnostic evidence). RESULTS: After being used to test 317 patients (32 with PcP), the overall performance of the PneumID assay was found to be excellent (Sensitivity/Specificity: 96.9%/95.1%). False positivity could be removed by applying a threshold specific to sample type (<33.1 cycles for BAL fluid; <37.0 cycles for throat swabs), whereas considering any positive respiratory samples as significant generated 100% sensitivity, making absolute negativity sufficient to exclude PcP. Incorporating the PneumID assay into diagnostic algorithms alongside (1-3)-ß-D-Glucan testing provided high probabilities of PcP (up to 85.2%) when both were positive and very low probabilities (<1%) when both were negative. CONCLUSIONS: The OLM PneumID qPCR provides a commercial option for the accurate diagnosis of PcP, generating excellent sensitivity and specificity, particularly when testing respiratory specimens. The combination of PcP PCR with serum (1-3)-ß-D-Glucan provides excellent clinical utility for diagnosing PcP.
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Background: Treatment for invasive candidiasis (IC) is time-critical, and culture-based tests can limit clinical utility. Nonculture-based methods such as Candida PCR represent a promising approach to improving patient management but require further evaluation to understand their optimal role and incorporation into clinical algorithms. This study determined the performance of the commercially available OLM CandID real-time PCR when testing serum and developed a diagnostic algorithm for IC. Methods: The study comprised a retrospective performance evaluation of the CandID real-time PCR assay when testing surplus serum (n = 83 patients, 38 with IC), followed by a prospective consecutive cohort evaluation (n = 103 patients, 24 with IC) post incorporation into routine service. A combined diagnostic algorithm, also including (1-3)-ß-D-Glucan testing, was generated. Results: Prospective CandID testing generated a sensitivity/specificity of 88%/82%, respectively. Specificity was improved (>95%) when both PCR replicates were positive and/or the patient had multiple positive samples. When combining CandID with (1-3)-ß-D-Glucan testing, the probability of IC when both were positive or negative was >69% or <1%, respectively. Conclusions: The CandID provides excellent performance and a rapid time-to-result using methods widely available in generic molecular diagnostic laboratories. By combining nonculture diagnostics, it may be possible to accurately confirm or exclude IC.
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Infections caused by the fungal pathogen Aspergillus fumigatus are increasingly resistant to first-line azole antifungal drugs. However, despite its clinical importance, little is known about how susceptible patients acquire infection from drug-resistant genotypes in the environment. Here, we present a population genomic analysis of 218 A. fumigatus isolates from across the UK and Ireland (comprising 153 clinical isolates from 143 patients and 65 environmental isolates). First, phylogenomic analysis shows strong genetic structuring into two clades (A and B) with little interclade recombination and the majority of environmental azole resistance found within clade A. Second, we show occurrences where azole-resistant isolates of near-identical genotypes were obtained from both environmental and clinical sources, indicating with high confidence the infection of patients with resistant isolates transmitted from the environment. Third, genome-wide scans identified selective sweeps across multiple regions indicating a polygenic basis to the trait in some genetic backgrounds. These signatures of positive selection are seen for loci containing the canonical genes encoding fungicide resistance in the ergosterol biosynthetic pathway, while other regions under selection have no defined function. Lastly, pan-genome analysis identified genes linked to azole resistance and previously unknown resistance mechanisms. Understanding the environmental drivers and genetic basis of evolving fungal drug resistance needs urgent attention, especially in light of increasing numbers of patients with severe viral respiratory tract infections who are susceptible to opportunistic fungal superinfections.
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Anti-Infecciosos , Aspergillus fumigatus , Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Humanos , Metagenômica , Testes de Sensibilidade MicrobianaRESUMO
Denture-associated stomatitis (DS) affects over two-thirds of denture-wearers. DS presents as erythema of the palatal mucosa in areas where denture-surface associated polymicrobial biofilms containing the fungus Candida albicans exist. The contribution of the oral bacterial microbiota toward the infection is unknown. Therefore, this study characterised the bacterial microbiota of sites within the oral cavity to identify potential associations with occurrence of DS. Denture-wearing patients were recruited (denture stomatitis (DS) n = 8; non-denture stomatitis (NoDS) n = 11) and the oral bacterial microbiota of the tongue, palate and denture-fitting surface was characterised using next-generation sequencing. Operational taxonomic units (OTUs) were identified to bacterial genera and species, and presence/absence and relative abundances were examined. A significant (P = 0.007) decrease in the number of OTUs and thus, diversity of the microbiota was observed in tongue samples of DS patients (vs non-DS). The microbiota of denture-fitting surfaces and palatal mucosae were similar. Large differences in the abundance of bacterial genera and species were observed at each sample site, and unique presence/absence of bacteria was noted. Presence/absence and relative abundance of specific bacteria associated with DS warrants further in vitro and in vivo evaluation, particularly as our previous work has shown C. albicans virulence factor modulation by oral bacteria.
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Dentaduras/microbiologia , Microbiota/genética , Estomatite sob Prótese/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias , Biofilmes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Boca/microbiologia , Mucosa Bucal/microbiologia , Palato/microbiologia , Estomatite/microbiologia , Fatores de VirulênciaRESUMO
AIMS: Although treatment for candidaemia is time critical, culture-based tests prolong turnaround times and may promote underdiagnosis. Non-culture-based tests have the potential to overcome these difficulties but are in limited clinical use. The aim of this work was to undertake an initial evaluation of two non-culture-based tests for diagnosis of candidaemia. METHODS: Patients with candidaemia were identified prospectively over a 4-month period. Sera drawn from case (candidaemic) and control (non-candidaemic) patients on the same day as the positive blood culture were tested with both the Renishaw RenDx Fungiplex test and a commercial ß-d-glucan (BDG) assay (Fungitell, Associates of Cape Cod). Sensitivity and specificity were calculated independently and in combination, using paired blood culture as the reference standard. RESULTS: There were 10 eligible case patients and 39 negative controls. PCR sensitivity and specificity were found to be 44.4% (95% CI 18.9% to 73.3%) and 87.2% (72.8% to 94.8%), respectively. BDG sensitivity and specificity were 80% (47.9% to 95.4%) and 89.7% (75.9% to 96.5%), respectively. When combining PCR and BDG, sensitivity was 90% (95% CI 57.4% to 100%) and specificity was 79.5% (64.2% to 89.5%). When two sequential specimens were tested, PCR sensitivity increased to 60% (95% CI 31.2% to 83.3%) and BDG sensitivity to 90% (54.7% to 100%). CONCLUSION: A combination of tests, or a single test at multiple time points, may be preferable to relying on one test at a single time point. This should be accounted for in design of future diagnostic accuracy studies of tests for invasive candidosis.
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Candida/genética , Candida/metabolismo , Candidemia/diagnóstico , DNA Fúngico/genética , Técnicas Microbiológicas , Reação em Cadeia da Polimerase , beta-Glucanas/sangue , Idoso , Biomarcadores/sangue , Candida albicans/genética , Candida albicans/metabolismo , Candida glabrata/genética , Candida glabrata/metabolismo , Candida parapsilosis/genética , Candida parapsilosis/metabolismo , Candidemia/sangue , Candidemia/microbiologia , Estudos de Casos e Controles , DNA Fúngico/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
Background/Objectives: Azole resistance in Aspergillus fumigatus associated with the TR34/L98H mutations in the cyp51A gene have been increasingly reported. Determining the environmental resistance rate has been deemed important when considering front-line therapy for invasive aspergillosis. The aim of the study was to determine prevalence of azole resistance in environmental A. fumigatus isolates across South Wales. Methods: Over 5 months in 2015, 513 A. fumigatus isolates were cultured from 671 soil and 44 air samples and were screened for azole resistance using VIPcheck™ agar plates containing itraconazole, voriconazole and posaconazole. Resistance was confirmed by the CLSI M38-A2 methodology. The mechanism of resistance was investigated using the PathoNostics AsperGenius® Assay. Results: Screening by VIPcheck™ plate identified azole-resistance in 30 isolates, most of which (28/30) harbored the TR34/L98H mutation, generating a prevalence of 6.0%. Twenty-five isolates had a MIC of ≥2 mg/L with itraconazole, 23 isolates had a MIC of ≥2 mg/L with voriconazole and seven isolates had a MIC ≥0.25 mg/L with posaconazole. All isolates deemed resistant by VIPcheck™ plates were resistant to at least one azole by reference methodology. Conclusions: There is significant environmental azole resistance (6%) in South Wales, in close proximity to patients susceptible to aspergillosis. Given this environmental reservoir, azole resistance should be routinely screened for in clinical practice and environmental monitoring continued.