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1.
Front Cell Infect Microbiol ; 14: 1321886, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558853

RESUMO

Cryptococcosis is a life-threatening invasive fungal infection with significantly increasing mortality worldwide, which is mainly caused by Cryptococcus neoformans and Cryptococcus gattii. These two species complexes have different epidemiological and clinical characteristics, indicating the importance of accurate differential diagnosis. However, the clinically used culture method and cryptococcal capsular antigen detection couldn't achieve the above goals. Herein, we established a novel duplex flap probe-based isothermal assay to identify the Cryptococcus neoformans and Cryptococcus gattii within 1 hour. This assay combined the highly sensitive nucleic acid isothermal amplification and highly specific fluorescence probe method, which could effectively distinguish the sequence differences of the two species complexes using two different fluorescence flap probes in a single reaction system. This novel method showed excellent detection performance with sensitivity (10 copies/µL each) and specificity (100%) compared to traditional culture and sequencing methods. Furthermore, we applied this method to spiked clinical samples, 30 cerebrospinal fluids and 30 bronchoalveolar lavage fluids, which kept good detection performance. This novel rapid duplex flap probe-based isothermal assay is a promising and robust tool for applications in differential diagnosis of the Cryptococcus neoformans and Cryptococcus gattii in clinical settings, especially when clinical suspicion for cryptococcal disease is high and epidemiological studies.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Cryptococcus neoformans/genética , Cryptococcus gattii/genética , Criptococose/diagnóstico , Criptococose/microbiologia , Antígenos de Fungos , Líquido da Lavagem Broncoalveolar
2.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612814

RESUMO

Ag nanoparticles (AgNPs) were biosynthesized using sage (Salvia officinalis L.) extract. The obtained nanoparticles were supported on SBA-15 mesoporous silica (S), before and after immobilization of 10% TiO2 (Degussa-P25, STp; commercial rutile, STr; and silica synthesized from Ti butoxide, STb). The formation of AgNPs was confirmed by X-ray diffraction. The plasmon resonance effect, evidenced by UV-Vis spectra, was preserved after immobilization only for the sample supported on STb. The immobilization and dispersion properties of AgNPs on supports were evidenced by TEM microscopy, energy-dispersive X-rays, dynamic light scattering, photoluminescence and FT-IR spectroscopy. The antioxidant activity of the supported samples significantly exceeded that of the sage extract or AgNPs. Antimicrobial tests were carried out, in conditions of darkness and white light, on Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans. Higher antimicrobial activity was evident for SAg and STbAg samples. White light increased antibacterial activity in the case of Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa). In the first case, antibacterial activity increased for both supported and unsupported AgNPs, while in the second one, the activity increased only for SAg and STbAg samples. The proposed antibacterial mechanism shows the effect of AgNPs and Ag+ ions on bacteria in dark and light conditions.


Assuntos
Antígenos de Grupos Sanguíneos , Nanopartículas Metálicas , Antioxidantes/farmacologia , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Prata/farmacologia , Antígenos de Fungos , Antibacterianos/farmacologia , Antígenos O , Dióxido de Silício , Extratos Vegetais/farmacologia
3.
BMC Infect Dis ; 24(1): 406, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627642

RESUMO

BACKGROUND: Opportunistic infections (OIs) are common causes of mortality among people living with HIV (PLHIV). We determined prevalence and 30-day mortality due to histoplasmosis, cryptococcosis, and TB in PLHIV with advanced HIV disease (AHD). METHODS: PLHIV 18 years and older, with a CD4 + T-cell count of less than 350 cells/mm3 newly diagnosed with HIV infection or re-engaged in care after being without ART for more than 90 days (Group A). The second group included symptomatic PLHIV regardless of ART status or CD4 + T-cell count (Group B); all followed for 30 days. Detection of Histoplasma Ag (HisAg) in urine was done by enzyme immunoassay (EIA), Cryptococcus antigen (CrAg) was detected in serum and cerebrospinal fluid (CSF) specimens by lateral flow assay (LFA), and lipoarabinomannan (LAM) detection in urine was by LFA (TB LAM) and in sputum by GeneXpert for diagnosis of Mycobacterium infections. RESULTS: From August 2021 to June 2022, 491 PLHIV were enrolled; 482 (98%) had a CD4 + T-cell result, and 381 patients (79%) were classified with AHD according to CD4 + T-cell count (< 200 CD4/mm3). Frequency of an OI was 38% (n = 145/381). Antigen test positivity rate was 16% (72/467) for TB-LAM, 9% (43/464) for HisAg, and 11% (51/484) for CrAg. Twenty-one of 34 (62%) patients receiving CSF CrAg tests were positive, confirming meningitis. Significant differences in 30-day mortality were observed in patients with an OI (16%) vs. no OI (7%) (p = 0.002). Mortality was highest in patients with histoplasmosis (25%), co-infection (22%), cryptococcosis (18% overall; 19% for cryptococcal meningitis), and TB (10%). CONCLUSIONS: TB and fungal OIs, including co-infection, were common in PLHIV in Paraguay and had high associated mortality. Laboratories and health facilities need access to CD4 + T-cell testing and rapid diagnostic assays.


Assuntos
Coinfecção , Criptococose , Infecções por HIV , Histoplasmose , Infecções Oportunistas , Tuberculose , Humanos , Infecções por HIV/epidemiologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Testes de Diagnóstico Rápido , Paraguai/epidemiologia , Criptococose/complicações , Criptococose/diagnóstico , Criptococose/epidemiologia , Tuberculose/complicações , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Antígenos de Fungos
4.
Front Immunol ; 15: 1347164, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487534

RESUMO

Introduction: Severe equine asthma (SEA) is a common chronic disease of adult horses with characteristic recurrent airway obstruction and similarities to neutrophilic asthma in humans. As an extrinsic stimulus, hay dust exposure is a major risk factor and induces acute exacerbation in susceptible horses. However, single inducing agents of SEA have hardly been identified on a molecular basis. Aspergillus fumigatus (A. fumigatus) is a common mold species in hay and has been described as a major provoking agent of SEA. Methods: Aiming to identify disease-relevant antigens, we analyzed A. fumigatus using an immunoproteomics approach on two-dimensional immunoblots of A. fumigatus protein probed with serum from environmentally matched asthmatic and healthy horses (n=5 pairs). A. fumigatus binding serum immunoglobulins (Pan-Ig), and the isotypes IgG4/7 and IgG3/5 were quantified for each protein spot and then compared between asthmatic and healthy horses. Results and discussion: For 21 out of 289 spots serum immunoglobulin (Ig) binding was different between the two groups for Pan-Ig or the isotypes. If differences were detected, Pan-Ig and IgG4/7 binding to the proteins were lower, while IgG3/5 binding was higher in asthmatic than healthy horse sera. Proteins were extracted from the 21 spots of interest and analyzed by liquid chromatography mass spectrometry. Eight prioritized proteins (candidate antigens) were expressed as recombinant proteins. Some of these have been previously described as major or minor A. fumigatus allergens, alongside other proteins, most with hydrolase activity. Recombinant candidate antigens were tested on 1D immunoblots to confirm their relevance as antigens by serum antibody binding. Four proteins (beta-hexosaminidase, class II aldolase/adducin domain protein, glucoamylase, peptide hydrolase B0XX53) showed different antibody binding characteristics between asthmatic and healthy horses and are likely relevant antigens in SEA. Their identification can provide the basis for innovative diagnostics, prevention, or therapeutic approaches. Additionally, a more profound understanding of SEA and its potential underlying mechanisms can be established. Elevated serum IgG3/5 antibodies correlate with T helper cell 2 responses in other equine pathologies, and the recombinant SEA antigens developed here can become instrumental in analyzing the involvement of SEA-specific T cell responses and Ig responses in future studies.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Humanos , Adulto , Animais , Cavalos , Aspergillus fumigatus , Asma/veterinária , Antígenos de Fungos , Imunoglobulina G
5.
Med Mycol ; 62(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38479779

RESUMO

Definitive diagnosis of histoplasmosis relies on culture and/or cytology/histopathology; however, these procedures have limited sensitivity and cultures are time-consuming. Antibodies detection by immunodiffusion has low sensitivity in immunocompromised individuals and uses histoplasmin (HMN), a crude antigenic extract, as reagent. Novel protein antigen candidates have been recently identified and produced by DNA-recombinant techniques to obtain standardized and specific reagents for diagnosing histoplasmosis. To compare the analytical performance of novel enzyme-linked immunosorbent assays (ELISAs) for antibodies testing for diagnosing histoplasmosis using different Histoplasma capsulatum antigens as reagents. The H. capsulatum 100 kDa protein (Hcp100), the M antigen and its immunoreactive fragment F1 were produced by DNA-recombinant techniques. Galactomannan was purified from both the yeast and mycelial cell walls (yGM and mGM, respectively). The analytical performance of the ELISA tests for the serological detection of antibodies against these antigens was evaluated and compared with those obtained using HMN as reagent. Antibodies detection by the Hcp100 ELISA demonstrated 90.0% sensitivity and 92.0% specificity, versus 43.3% sensitivity and 95.0% specificity of the M ELISA, 33.3% sensitivity and 84.0% specificity of the F1 ELISA, 96.7% sensitivity and 94.0% specificity of the yGM ELISA, 83.3% sensitivity and 88.0% specificity of the mGM ELISA, and 70.0% sensitivity and 86.0% specificity for the HMN ELISA. In summary, Hcp100 is proposed as the most promising candidate for the serodiagnosis of histoplasmosis. The primary immunoreactive element in HMN proved to be GM rather than the M antigen. Nevertheless, a higher incidence of cross-reactions was noted with GM compared to M.


Hcp100 is a promising serodiagnostic candidate for histoplasmosis, boasting high sensitivity and specificity. Notably, GM, rather than M antigen, emerged as the primary immunoreactive element in HMN, despite a higher incidence of cross-reactions with GM compared to M.


Assuntos
Histoplasmose , Humanos , Histoplasmose/diagnóstico , Histoplasmose/veterinária , Histoplasma/genética , Anticorpos Antifúngicos , Técnicas Imunoenzimáticas , Antígenos de Fungos , Anticorpos , Imunodifusão/veterinária , Saccharomyces cerevisiae , DNA
6.
Mycoses ; 67(3): e13709, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38429225

RESUMO

BACKGROUND: Cryptococcal meningitis (CM), an opportunistic fungal infection affecting immunocompromised hosts, leads to high mortality. The role of previous exposure to glucocorticoids as a risk factor and as an outcome modulator has been observed, but systematic studies are lacking. OBJECTIVE: The primary aim of this study is to evaluate the impact of glucocorticoid use on the clinical outcomes, specifically mortality, of non-HIV and non-transplant (NHNT) patients diagnosed with CM. METHODS: We queried a global research network to identify adult NHNT patients with CM based on ICD codes or recorded specific Cryptococcus CSF lab results with or without glucocorticoid exposure the year before diagnosis. We performed a propensity score-matched analysis to reduce the risk of confounding and analysed outcomes by glucocorticoid exposure. We used a Cox proportional hazards model for survival analysis. RESULTS: We identified 764 patients with a history of glucocorticoid exposure and 1267 patients without who developed CM within 1 year. After propensity score matching of covariates, we obtained 627 patients in each cohort. The mortality risk in 1 year was greater in patients exposed to prior glucocorticoids (OR: 1.3, CI: 1.2-2.0, p = 0.002). We found an excess of 45 deaths among CM patients with previous glucocorticoid use (7.4% increased absolute risk of dying within 1 year of diagnosis) compared to CM controls without glucocorticoid exposure. Hospitalisation, intensive care unit admission, emergency department visits, stroke and cognitive dysfunction also showed significant, unfavourable outcomes in patients with glucocorticoid-exposed CM compared to glucocorticoid-unexposed CM patients. CONCLUSIONS: Previous glucocorticoid administration in NHNT patients seems to associate with 1-year mortality after CM adjusted for possible confounders related to demographics, comorbidities and additional immunosuppressive medications. Serial CrAg screening might be appropriate for higher-risk patients on glucocorticoids after further cost-benefit analyses.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Cryptococcus neoformans , Cryptococcus , Infecções por HIV , Meningite Criptocócica , Adulto , Humanos , Meningite Criptocócica/microbiologia , Glucocorticoides/efeitos adversos , Fatores de Risco , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/microbiologia , Antígenos de Fungos
8.
Clin Microbiol Infect ; 30(5): 682.e1-682.e4, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38309324

RESUMO

OBJECTIVES: This study aimed to identify the cause of false-positive serum Aspergillus antigen galactomannan (GM) results in our centre. METHODS: We performed a case-control study aiming to elucidate the factors associated with false-positive GM results. Independent risk factors for false-positive GM were evaluated through a multivariable regression analysis. An interrupted time series analysis was used to evaluate the effectiveness of an intervention removing the identified factors. RESULTS: Among 568 patients tested, GM was positive in 130 patients of whom 97 had false-positive GM (cases). These were compared with 427 patients with true-negative GM (controls). Administration of dextrose-containing fluids within 6 days before GM testing was an independent predictor for false-positive GM results (adjusted odds ratio [aOR], 18.60; 95% CI, 8.95-38.66. An analysis of GM presence in different dextrose-containing fluids revealed positivity in 34.8% (8 of 23) (manufacturer A) and 33.3% (5 of 15) (manufacturer B) of the samples. Investigation of the manufacturing process revealed that the saccharification process employed enzymes derived from Aspergillus niger. After identifying the root cause of false positivity, GM-containing dextrose fluid use was restricted. Interrupted time series analysis showed an immediate reduction of GM false-positivity (-6.5% per week, p = 0.045) and a declining trend (-0.33% per week, p = 0.005) postintervention. CONCLUSIONS: Administering dextrose-containing fluids was the primary factor causing false-positive serum Aspergillus antigen GM assay results. Our investigation led to a modification of the manufacturing process of the dextrose-containing fluids.


Assuntos
Antígenos de Fungos , Aspergilose , Galactose/análogos & derivados , Glucose , Análise de Séries Temporais Interrompida , Mananas , Humanos , Mananas/sangue , Estudos de Casos e Controles , Glucose/análise , Reações Falso-Positivas , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Antígenos de Fungos/sangue , Aspergilose/diagnóstico , Aspergilose/sangue , Adulto , Aspergillus/imunologia , Aspergillus/isolamento & purificação , Fatores de Risco , Aspergillus niger
9.
BMC Infect Dis ; 24(1): 162, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321369

RESUMO

BACKGROUND: Pulmonary cryptococcosis (PC) rarely occurs in immunocompetent children. CASE PRESENTATION: A 13-year-old boy was admitted to the First Affiliated Hospital of Ningbo University in February 2023 with complaints of cough and chest pain. Physical examination showed slightly moist rales in the right lung. Chest computed tomography (CT) suggested a lung lesion and cavitation. Blood routine test, lymphocyte subsets, immunoglobulin, and complement tests indicated that the immune system was normal. However, the serum cryptococcal antigen test was positive. Next-generation sequencing revealed Cryptococcus infection. The child was diagnosed with PC and was discharged after treating with fluconazole 400 mg. Four months later, chest CT showed that the lung lesion diminished, and reexamination of serum cryptococcal antigen test turned positive. CONCLUSION: PC should be considered in an immunocompetent child with pulmonary cavities with nonspecific symptoms.


Assuntos
Criptococose , Masculino , Criança , Humanos , Adolescente , Criptococose/diagnóstico , Fluconazol , Pulmão , Tomografia Computadorizada por Raios X , Antígenos de Fungos
10.
Sci Rep ; 14(1): 261, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168000

RESUMO

An enzyme-free sandwich amperometric immunosensor based on bimetallic Pt/Ag nanoparticle (Pt/AgNPs)-functionalized chitosan (Chi)-modified multiwalled carbon nanotubes (MWCNTs) as dual signal amplifiers and Chi-modified MWCNTs (MWCNTs-Chi) as substrate materials was developed for ultrasensitive detection of fowl adenovirus group I (FAdV-I). MWCNTs have a large specific surface area, and many accessible active sites were formed after modification with Chi. Hence, MWCNTs-Chi, as a substrate material for modifying glassy carbon electrodes (GCEs), could immobilize more antibodies (fowl adenovirus group I-monoclonal antibody, FAdV-I/MAb). Multiple Pt/AgNPs were attached to the surface of MWCNTs-Chi to generate MWCNTs-Chi-Pt/AgNPs with high catalytic ability for the reaction of H2O2 and modified active sites for fowl adenovirus group I-polyclonal antibody (FAdV-I/PAb) binding. Amperometric i-t measurements were employed to characterize the recognizability of FAdV-I. Under optimal conditions, and the developed immunosensor exhibited a wide linear range (100.93 EID50 mL-1 to 103.43 EID50 mL-1), a low detection limit (100.67 EID50 mL-1) and good selectivity, reproducibility and stability. This immunosensor can be used in clinical sample detection.


Assuntos
Técnicas Biossensoriais , Antígenos de Grupos Sanguíneos , Nanopartículas Metálicas , Nanotubos de Carbono , Nanotubos de Carbono/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas , Reprodutibilidade dos Testes , Peróxido de Hidrogênio , Imunoensaio , Prata , Antígenos de Fungos , Anticorpos Monoclonais , Adenoviridae , Limite de Detecção , Ouro/química
11.
Sci Rep ; 14(1): 2552, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38291146

RESUMO

Galactomannan (GM) is a polysaccharide cell wall component released by Aspergillus spp., and an immunoenzymatic GM assay is used for the diagnosis of invasive pulmonary aspergillosis. We evaluated the cause of strong positivity for GM in patients with no typical signs of aspergillosis. Repeat assays were performed using different instruments and reagent lots, but there were no differences in results among the assays. Patients with strongly positive GM results were investigated. Medication histories revealed that 14 of 23 patients had been administered total parenteral nutrition solution from one manufacturer and 4 patients had been administered dextrose solution from a different manufacturer before being tested. The results of GM assays conducted on samples of dextrose solution and the glucose fraction of the total parenteral nutrition solution were strongly positive, confirming the causes of the false-positive reactions. We hypothesize that a trace amount of GM was introduced into the glucose-containing solutions because glucoamylase, which is necessary for the saccharification step of glucose synthesis, was derived from Aspergillus niger. To enhance patient care and prevent unnecessary antifungal prescriptions, healthcare providers and manufacturers of healthcare products need to be aware of the possibility of false-positive reactions for GM.


Assuntos
Aspergilose , Humanos , Aspergilose/tratamento farmacológico , Mananas , Galactose , Glucose/uso terapêutico , Soluções de Nutrição Parenteral , Sensibilidade e Especificidade , Antígenos de Fungos
12.
Mycoses ; 67(1): e13670, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37897135

RESUMO

PURPOSE: H. capsulatum is endemic in Indonesia, but the value of Histoplasma antigen detection has not been studied. PATIENTS AND METHODS: Histoplasma galactomannan (GM) ELISA was applied to sera of patients with unproven pulmonary tuberculosis (TB) and patients with a positive Aspergillus GM. Both Histoplasma and Aspergillus GM tests were performed to determine any possible cross-reaction with certain foods. RESULTS: Fourteen of 122 (11.5%) sera of patients with newly diagnosed clinical TB were positive for Histoplasma GM. The positivity rate in the serum of patients 5-6 and 12 months after TB diagnosis was 3.8% and 3.5%, respectively. Of 88 positive Aspergillus GM sera, 63 (71.6%) were also positive for Histoplasma GM. All tested foods were positive for Aspergillus GM, while 65% of foods were positive for Histoplasma GM. CONCLUSION: Galactomannan is widespread in sera and food in Jakarta, possibly related to food consumption. Histoplasma and Aspergillus antigen detection for the diagnosis will require additional means of confirming the diagnosis; negative tests may be more helpful for ruling out invasive histoplasmosis and aspergillosis.


Assuntos
Aspergilose , Histoplasmose , Humanos , Histoplasma , Indonésia , Histoplasmose/diagnóstico , Aspergilose/diagnóstico , Aspergillus , Antígenos de Fungos , Mananas/análise , Sensibilidade e Especificidade
13.
mBio ; 15(1): e0276923, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38088540

RESUMO

IMPORTANCE: Candidemia (bloodstream invasion by Candida species) is a major fungal disease in humans. Despite the recent progress in diagnosis and treatment, therapeutic options are limited and under threat of antimicrobial resistance. The disease mortality remains high (around 40%). In contrast with deep-seated invasive candidiasis, particularly that occurring in patients with hematologic malignancies and organ transplants, patients with candidemia are often not immunocompromised and therefore able to mount memory anticandidal immune responses, perhaps primed by Candida commensalism. We investigated antibody immunity in candidemia patients and report here on the ability of these patients to produce antibodies that react with Candida antigens. In particular, the patients with high titers of IgG reactive with two immunodominant, virulence-associated antigens (Als3 and MP65) had a higher 30-day survival. If confirmed by controlled, prospective clinical studies, our data could inform the development of antibody therapy to better treat a severe fungal infection such as candidiasis.


Assuntos
Candidemia , Candidíase Invasiva , Humanos , Candida , Candidemia/diagnóstico , Candidemia/tratamento farmacológico , Estudos Prospectivos , Candidíase Invasiva/tratamento farmacológico , Antígenos de Fungos , Anticorpos/uso terapêutico , Antifúngicos/uso terapêutico
14.
J Clin Microbiol ; 62(1): e0121323, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38099670

RESUMO

Histoplasma and Blastomyces antigen detection assays are commonly used diagnostic tools. However, a high level of cross-reactivity between these antigens prevents definitive pathogen identification by these assays alone. Retrospective analysis of 3,529 patients with Histoplasma and Blastomyces antigen testing performed on the same serum sample yielded an overall percent agreement of 99.3% (3,506 of 3,529; kappa: 0.859) between the two assays, suggesting that use of a single assay to detect both antigens may be an alternative diagnostic approach. We assessed performance of the Gotham BioTech Blastomyces antigen (GBA) enzyme immunoassay (EIA) (Portland, Maine) for detection of Blastomyces and Histoplasma antigens in serum. Comparison to the MiraVista Diagnostics Blastomyces (MVB) EIA showed 100% positive (24 of 24), negative (57 of 57), and overall (81 of 81) percent agreement. Additionally, 171 sera were used to compare the GBA EIA to the MiraVista Diagnostics Histoplasma (MVH) EIA, which showed 91.3% (63 of 69), 98% (100 of 102), and 95.3% (163 of 171) positive, negative, and overall percent agreement, respectively. Among eight patients with discordant GBA/MVH EIA results, seven had additional fungal testing performed, and results suggested that the MVH and GBA results were inaccurate for two and five samples, respectively. Overall, this study suggests that the GBA EIA has a high level of agreement with both of the commonly used, individual Blastomyces and Histoplasma antigen EIAs. By taking advantage of the high level of cross-reactivity between Blastomyces and Histoplasma antigen EIAs, utilization of a single antigen detection assay for these fungi provides an opportunity to optimize test utilization and decrease patient cost while maintaining a high level of diagnostic accuracy.


Assuntos
Blastomyces , Histoplasma , Humanos , Estudos Retrospectivos , Antígenos de Fungos , Técnicas Imunoenzimáticas
15.
Medicina (B Aires) ; 83(6): 863-874, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38117705

RESUMO

INTRODUCTION: Histoplasmosis is a systemic mycosis of universal distribution, highly endemic in the Americas. It is caused by a dimorphic fungus Histoplasma capsulatum var. capsulatum. It affects both immunocompetent and immunocompromised individuals where progressive and disseminated forms are observed. A very important risk factor is HIV infection/AIDS, with a mortality rate of 20-40% in Latin America. The diagnosis of this mycosis is made by conventional and molecular methods or by antigen and antibody detection. METHODS: In this retrospective, longitudinal and analytical study, carried out over a period of 2 years, the sensitivity (S) and specificity (E) of a commercial kit for the detection of Histoplasma antigen by EIA technique (HC-Ag) was evaluated in 50 patients with AIDSassociated histoplasmosis. In addition, its performance was compared with that of other diagnostic techniques routinely used in our laboratory. RESULTS: HC-Ag had a S of 94%, E 96%, positive likelihood coefficient (CVP): 20.68 and negative likelihood coefficient (CVN): 0.06. The delay time of the results was 4 days, similar to that of antibody detection and n-PCR and much less than that of blood cultures. The combination of methods improved S to 100%; with similar values in E. CONCLUSION: The HC-Ag method demonstrated its usefulness in the diagnosis of progressive disseminated histoplasmosis and the combination of methods is a good option to increase sensitivity and decrease the time to reach the diagnosis of certainty. This allows improving the strategy in the management of the disease and decreasing its case-fatality rate.


Introducción: La histoplasmosis es una micosis sistémica de distribución universal, altamente endémica en las Américas. Es causada por un hongo dimórfico: Histoplasma capsulatum var. capsulatum. Afecta tanto a inmunocompetentes como a inmunocomprometidos, se observan formas progresivas y diseminadas. Un factor de riesgo muy importante es la infección por HIV/sida, con una tasa de mortalidad del 20-40% en América Latina. El diagnóstico de esta micosis se realiza por métodos convencionales y moleculares o por detección de antígenos y anticuerpos. Métodos: En este estudio retrospectivo, longitudinal y analítico, realizado en un periodo de 2 años, se evaluó la sensibilidad (S) y especificidad (E) de un kit comercial para la detección de antígeno de Histoplasma por técnica de EIA (HC-Ag) en 50 pacientes con histoplasmosis asociada a sida. Además, se comparó su rendimiento con el de otras técnicas diagnósticas utilizadas habitualmente en nuestro laboratorio. Resultados: HC-Ag tuvo una S del 94%, E del 96%, coeficiente de verosimilitud positiva (CVP) de 20.68 y coeficiente de verosimilitud negativa (CVN) de 0.06. El tiempo de demora de los resultados fue de 4 días, similar al de la detección de anticuerpos y n-PCR y mucho menor que el de los hemocultivos. La combinación de métodos mejoró la S a 100%; con valores similares en E. Conclusión: El método HC-Ag demostró su utilidad en el diagnóstico de histoplasmosis diseminada progresiva y la combinación de métodos es una buena opción para aumentar la sensibilidad y disminuir el tiempo para llegar al diagnóstico de certeza. Esto permite mejorar la estrategia en el manejo de la enfermedad y reducir su tasa de letalidad.


Assuntos
Infecções por HIV , Histoplasmose , Humanos , Histoplasmose/diagnóstico , Histoplasma , Estudos Retrospectivos , Argentina/epidemiologia , Técnicas Imunoenzimáticas , Antígenos de Fungos/análise
16.
Ann Clin Lab Sci ; 53(5): 765-770, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37945009

RESUMO

OBJECTIVE: We presented the performance of cryptococcal antigen lateral flow assay test using bronchoalveolar lavage fluid (BALF) samples in the HIV-negative Chinese population. METHODS: From January 2019 to June 2022, cryptococcal antigen was detected in both serum and BALF samples from 113 patients with suspected pulmonary cryptococcosis. RESULTS: 49 patients were finally diagnosed with pulmonary cryptococcosis. The sensitivity of cryptococcal antigen lateral flow assay test in serum and BALF specimens from confirmed cases was 90.0% and 96.0%, respectively, and the specificity was 87.3% and 95.5%, respectively. When the diameter of the lung lesion was less than 15 mm, the antigen positivity rate of BALF was higher than that of serum. Moreover, the result of the cryptococcal antigen test was associated with the lymphocytes count of BALF. CONCLUSION: Our data demonstrate that cryptococcal antigen Lateral Flow Assay for BALF specimens might contribute to the early diagnosis of pulmonary cryptococcosis.


Assuntos
Criptococose , Cryptococcus , Infecções por HIV , Humanos , Líquido da Lavagem Broncoalveolar , Criptococose/diagnóstico , Testes Imunológicos , Antígenos de Fungos , Infecções por HIV/complicações
17.
Allergy Asthma Proc ; 44(6): 395-401, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37919848

RESUMO

Background: Allergy immunotherapy (AIT) with fungal extracts is not as straight forward as that with other inhalants. The complexities relate to the number of airborne fungal spores, the limited data on the exposure to the spores of individual species of fungi and their clinical importance, the poor quality of the fungal allergen extracts that are available for the diagnosis and treatment, and the lack of controlled studies establishing dosing and efficacy of AIT with fungal extracts except for Alternaria. Objective: The objective was to review what is known with regard to the role of fungi in causing allergic respiratory diseases as well as the evidence that exists for the role of AIT as a treatment for these conditions. Methods: A search was conducted of PubMed, textbooks, known articles on immunotherapy with fungal extracts, and references derived from these primary sources. Results: Nine immunotherapy studies that used Alternaria or its major allergen Alt a 1 and two studies that used Cladosporium herbarum were identified. When a good quality extract was administered in adequate doses, immunotherapy with Alternaria was as effective as that with other inhalant allergens. There was a suggestion of efficacy with a specially prepared Cladosporium extract, but systemic reactions were common and limited the tolerated dose. The use of immunotherapy as an adjunct treatment for allergic fungal sinusitis is briefly reviewed, but controlled trials are lacking. Conclusion: Fungal immunotherapy should largely be limited to Alternaria alternata and perhaps C. herbarum. Under conditions of demonstrated exposure to a particular species of fungus and with symptoms that correlate with that exposure as well as availability of an apparently potent extract of that fungus to which the patient is sensitive that fungus may be considered for immunotherapy. Fungal (mold) mixes should not be used for diagnosis or therapy.


Assuntos
Hipersensibilidade , Transtornos Respiratórios , Humanos , Alérgenos/uso terapêutico , Antígenos de Fungos , Hipersensibilidade/terapia , Hipersensibilidade/diagnóstico , Imunoterapia , Extratos Vegetais
18.
BMC Pulm Med ; 23(1): 427, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925443

RESUMO

BACKGROUND: Sarcoidosis and hypersensitivity pneumonitis (HP) are two distinct clinical entities that share granulomatous inflammation, although each of them has specific clinical, radiologic and pathologic profiles. Coexistence of the two diseases have been described, suggesting, at least in some cases, a common biologic background. CASE PRESENTATION: We describe two patients showing the concurrent diagnosis of sarcoidosis and hypersensitivity pneumonitis. Case 1: a 51-year old never smoker man had a history of occupational exposure, episodes of acute exacerbations and positive serum precipitins to Penicillium spp suggestive of HP, while the positivity of serum angiotensin converting enzyme (ACE) favored sarcoidosis. Case 2: a 42-year old non-smoker woman with occasional finding of enlarged mediastinal lymph nodes had a history of domestic exposure to molds and positive serum precipitins to Aspergillus spp suggestive of HP. In both cases high resolution computed tomography (HRCT) together with broncoscopy findings allowed to maintain both the diagnoses: HRCT showed both enlarged hilar/mediastinal limph nodes and intersitial lung involvement typical of HP; bronchoalveolar lavage presented marked lymphocytosis and granulomatous nodal lesions were observed at transbronchial needle aspiration. CONCLUSIONS: Sarcoidosis and HP share some clinical findings and the differential diagnosis may be difficult. Our cases suggest that a common trait may be responsible for the concurrent diagnosis of sarcoidosis and hypersensitivity pneumonitis in the same patient.


Assuntos
Alveolite Alérgica Extrínseca , Sarcoidose , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Adulto , Precipitinas , Antígenos de Fungos , Alveolite Alérgica Extrínseca/complicações , Alveolite Alérgica Extrínseca/diagnóstico , Sarcoidose/complicações , Sarcoidose/diagnóstico , Lavagem Broncoalveolar , Granuloma/patologia
19.
J Clin Microbiol ; 61(11): e0059823, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37823667

RESUMO

Fungal antigens such as ß-(1→3)-D-glucan (BDG) or mannan (Mn) are useful for detection of candidemia. However, detailed data on serum levels before diagnosis and during treatment are scarce. We conducted a prospective study at two German tertiary care centers for 36 months. Sera from adult patients with candidemia were tested for BDG (Fungitell assay) and Mn (Platelia Candida Ag-Plus assay). For each patient, the clinical course and biomarker kinetics were closely followed and compared. 1,243 sera from 131 candidemia episodes and 15 relapses were tested. In 35% of episodes, empirical therapy included an antifungal drug. Before blood culture sampling, BDG and Mn levels were elevated in 62.4% and 30.8% of patients, respectively. Sensitivity at blood culture sampling was 78.6% (BDG) and 35.1% (Mn). BDG levels of non-survivors were significantly higher than those of survivors. During follow-up, a therapeutic response was associated with decreasing BDG and Mn levels in 84.3% or 70.5% of episodes, respectively. A median increase of 513 pg BDG/mL and 390 pg Mn/mL indicated a relapse of candidemia with a sensitivity of 80% or 46.7%, respectively. In 72.9% and 46.8% of patients, increasing BDG or Mn levels were associated with a fatal outcome. Prior to discharge, BDG and Mn levels had dropped or normalized in 65.7% or 82.1% of patients, respectively. Summarising, in patients with candidemia, biomarker positivity usually precedes culture positivity. Relapses are mostly accompanied by secondary biomarker increases. Rising concentrations of BDG and Mn predict lethality, whereas decreasing levels suggest a favorable outcome in the majority of patients.


Assuntos
Candidemia , beta-Glucanas , Adulto , Humanos , Candidemia/diagnóstico , Candidemia/tratamento farmacológico , Candidemia/microbiologia , Mananas , Glucanos/uso terapêutico , Estudos Prospectivos , Sensibilidade e Especificidade , Antígenos de Fungos , Biomarcadores , Recidiva
20.
Microbiol Spectr ; 11(6): e0167323, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37800931

RESUMO

IMPORTANCE: This manuscript describes an occurrence of false-positive GM tests in patients receiving TPN products from a manufacturer who had recently changed the supplier of the glucose component. We describe the clinical presentation of nine false-positive cases and the results of serologic and microbiological investigations of the TPN products suspected of contamination with GM. Attempts to detect GM in parenteral nutrition products were made since the detection of GM in sodium gluconate-containing solutions in 2007, but none of them identified the source of elevated GM indexes in TPN products. However, the present study demonstrated that the glucose component of the TPN products contained a high level of GM antigen, which caused false-positive GM assay results. The source of GM was glucoamylase, which was derived from A. niger in the manufacturing process. Physicians and clinical microbiology laboratories should be aware of this issue to improve interpretation and patient care.


Assuntos
Aspergillus , Mananas , Humanos , Reações Falso-Positivas , Imunoensaio , Nutrição Parenteral Total , Antígenos de Fungos
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