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BACKGROUND: Rapid galactomannan tests, such as the sõna Aspergillus GM Lateral Flow Assay (GM-LFA) and the Aspergillus Galactomannan Ag VIRCLIA® Monotest (GM-Monotest), which are suitable for the analysis of single samples, have the potential to accelerate diagnosis of invasive aspergillosis (IA). OBJECTIVES: To compare the performance of the GM-Monotest and the GM-LFA for the diagnosis of IA. PATIENTS/METHODS: Two patient cohorts were analysed: adults who had received an allogeneic haematopoietic stem-cell transplant (alloHSCT-cohort) and patients with proven/probable IA from a 5-year period (cross-sectional IA-cohort). In the alloHSCT-cohort, weekly serum samples were tested, whereas in the cross-sectional IA-cohort sera and bronchoalveolar lavage fluids were analysed. The diagnostic performance was calculated using two definitions for positivity: (1) a single positive GM result and (2) at least two positive GM results from consecutive samples. IA classification followed EORTC/MSG 2019. RESULTS: The alloHSCT-cohort included 101 patients. Four had proven/probable IA, 26 possible IA and 71 no IA. The specificity for one positive serum and two consecutively positive sera was 88.7% and 100% (GM-Monotest) and 85.9% and 98.6% (GM-LFA). Comparison of ROC curves in the alloHSCT-cohort showed no significant difference. The cross-sectional IA-cohort included 59 patients with proven/probable IA. The sensitivity for one positive sample and two consecutively positive samples was 83.1% and 55.1% (GM-Monotest) and 86.4% and 71.4% (GM-LFA). CONCLUSIONS: Both assays showed comparable diagnostic performance with a higher sensitivity for the GM-LFA if two consecutive positive samples were required for positivity. However, due to poor reproducibility, positive GM-LFA results should always be confirmed.
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Aspergillus , Galactosa , Mananos , Sensibilidad y Especificidad , Humanos , Mananos/sangre , Mananos/análisis , Galactosa/análogos & derivados , Masculino , Persona de Mediana Edad , Femenino , Estudios Transversales , Adulto , Anciano , Aspergillus/aislamiento & purificación , Aspergillus/inmunología , Aspergilosis Pulmonar Invasiva/diagnóstico , Antígenos Fúngicos/sangre , Antígenos Fúngicos/análisis , Líquido del Lavado Bronquioalveolar/microbiología , Líquido del Lavado Bronquioalveolar/química , Inmunoensayo/métodos , Trasplante de Células Madre Hematopoyéticas , Aspergilosis/diagnóstico , Aspergilosis/microbiología , Estudios de Cohortes , Adulto JovenRESUMEN
OBJECTIVE: Cryptococcosis predominantly presents as a meningoencephalitis in Thailand. Early and expeditious diagnosis is essential for reducing both mortality and morbidity associated with cryptococcal meningitis. We aim to define and establish the diagnostic performances between the benchmark commercially available diagnostic kit (CrAg® LFA) and the large-scale prototype of an inexpensive in-house immunochromatographic test (ICT) based on monoclonal antibody (MAb) 18B7. METHODS: We have developed the large-scale prototype for the rapid detection of cryptococcal polysaccharide antigens by utilizing a single antibody sandwich ICT format employing MAb 18B7, which is highly specific to Cryptococcus neoformans glucuronoxylomannan (GXM) antigens. An in-house MAb18B7 ICT was manufactured in accordance with industry standards under the control of the International Organization for Standardization (ISO) 13485. RESULTS: The diagnostic sensitivity, specificity, and accuracy for the in-house MAb 18B7 ICT were 99.10%, 97.61%, and 97.83%, respectively. The agreement kappa (κ) coefficient was 0.968 based on the retrospective evaluation of 580 specimens from patients living in northern Thailand with clinically suspected cryptococcosis. CONCLUSION: The data suggest that this in-house MAb 18B7 ICT will be highly beneficial for addressing the issue of cryptococcal infection in Thailand. Moreover, it is anticipated that this inexpensive ICT can play a pivotal role in various global strategies aimed at eradicating cryptococcal meningitis among individuals living with HIV by 2030.
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Anticuerpos Monoclonales , Antígenos Fúngicos , Cromatografía de Afinidad , Criptococosis , Cryptococcus neoformans , Sensibilidad y Especificidad , Humanos , Tailandia , Anticuerpos Monoclonales/inmunología , Cromatografía de Afinidad/métodos , Criptococosis/diagnóstico , Cryptococcus neoformans/inmunología , Cryptococcus neoformans/aislamiento & purificación , Antígenos Fúngicos/análisis , Antígenos Fúngicos/inmunología , Estudios Retrospectivos , Anticuerpos Antifúngicos/sangre , Polisacáridos/análisis , Polisacáridos/inmunología , Masculino , Femenino , Adulto , Pruebas Diagnósticas de Rutina/métodos , Persona de Mediana Edad , Anciano , Adulto JovenRESUMEN
Aspergillus species can colonize and infect immunocompetent and immunocompromised hosts. Conventional fungal identification depends on microscopic analysis and microorganism medium growth. Other diagnostic methods, non-growth dependent, to invasive fungal infections, are the biomarkers that detect circulating polysaccharides, for example, 1-3-ß-d-Glucan and galactomannan. Both are polysaccharides present on the external layer of fungi cell wall and can be detected in clinical samples during the growth of the fungus in the patient. This study aimed to compare the galactomannan detection of Lateral Flow Assay and Enzyme Immunoassay methods in Bronchoalveolar Lavage Fluid. The galactomannan antigen in Bronchoalveolar Lavage Fluid was measured using Enzyme Immunoassay according to the manufacturer's instructions (PLATELIA ASPERGILLUS™ BioRad) and, using a Lateral Flow Assay according to the manufacturer's instructions (Galactomannan LFA IMMY©). The 71 samples were Bronchoalveolar Lavage Fluid of patients hospitalized at Unicamp Clinical Hospital between 2019 and 2021; of these samples 12/71 (16.9 %) resulted in positive Galactomannan-Lateral Flow Assay. In contrast, Galactomannan-Enzyme Immunoassay resulted as positive in 9/71 (12.6 %) samples, a difference that showed not significant statistically (p-value = 0.36) Comparing both assays' results identified 8 divergences between them, about 11 % of the total sample. The Sensitivity (73.3 %), Specificity (92.35 %), Positive Predictive Value (62.85 %) and Negative Predictive Value (95.15 %) of Lateral Flow Assay were calculated using the Galactomannan Enzyme Immunoassay as standard. The Lateral Flow Assay demonstrated good results when compared with the Enzyme Immunoassay.
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Aspergillus , Líquido del Lavado Bronquioalveolar , Galactosa , Técnicas para Inmunoenzimas , Mananos , Sensibilidad y Especificidad , Mananos/análisis , Galactosa/análogos & derivados , Humanos , Líquido del Lavado Bronquioalveolar/microbiología , Líquido del Lavado Bronquioalveolar/química , Aspergillus/inmunología , Aspergillus/aislamiento & purificación , Técnicas para Inmunoenzimas/métodos , Aspergilosis/diagnóstico , Aspergilosis/microbiología , Biomarcadores/análisis , Antígenos Fúngicos/análisis , Reproducibilidad de los ResultadosRESUMEN
The Platelia Aspergillus Antigen immunoassay is the "gold standard" for Aspergillus galactomannan (GLM) measurement in sera and bronchoalveolar lavage (BAL) for the diagnosis of invasive pulmonary aspergillosis (IPA). We evaluated the performance of the Aspergillus GLM antigen Virclia Monotest compared to the Platelia assay. A total of 535 specimens [320 sera, 86 bronchial aspirates (BAs), 70 BAL, and 59 tracheal aspirates (TAs)] from 177 adult patients (72 hematological, 32 Intensive Care Unit, and 73 hospitalized in other wards) were processed for GLM testing upon clinical request. One patient had proven IPA, and 11 had probable disease. After excluding indeterminate Virclia results (n = 38), 396 specimens yielded concordant results (56 positive and 340 negative) and 101 discordant results (Virclia positive/Platelia negative, n = 95). The overall agreement between immunoassays was higher for sera (κ 0.56) than for BAL (κ ≤ 0.24) or BAS and TA (κ ≤ 0.22). When considering all specimen types in combination, the overall sensitivity and specificity of the Virclia assay for the diagnosis of proven/probable IPA were 100% and 65%, respectively, and for the Platelia immunoassay, sensitivity and specificity were 91.7% and 89.4%, respectively. The correlation between index values by both immunoassays was strong for serum/BAL (ρ = 0.73; P < 0.001) and moderate for BAS/TA (Rho = 0.52; P = 0.001). The conversion of Virclia index values into the Platelia index could be derived by the formula y = (11.97 * X)/3.62 + X). Data from GLM-positive serum/BAL clinical specimens fitted the regression model optimally (R2 = 0.94), whereas that of BAS and TA data did not (R2 = 0.11). Further studies are needed to determine whether the Virclia assay may be an alternative to the Platelia assay for GLM measurement in sera and lower respiratory tract specimens.IMPORTANCEGalactomannan detection in serum or bronchoalveolar fluid specimens is pivotal for the diagnosis of invasive pulmonary aspergillosis (IPA). The Platelia Aspergillus Antigen immunoassay has become the "gold standard" for Aspergillus GLM measurement. Here, we provide data suggesting that the Virclia Monotest assay, which displays several operational advantages compared with the Platelia assay, may become an alternative to the Platelia assay, although further studies are needed to validate this assumption. We also provide a formula allowing the conversion of Virclia index values into Platelia values. The study may contribute toward positioning the Virclia assay within the diagnostic algorithm of IPA.
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Antígenos Fúngicos , Aspergillus , Galactosa , Mananos , Sensibilidad y Especificidad , Humanos , Galactosa/análogos & derivados , Mananos/análisis , Mananos/sangre , Antígenos Fúngicos/análisis , Antígenos Fúngicos/sangre , Antígenos Fúngicos/inmunología , Aspergillus/inmunología , Aspergillus/aislamiento & purificación , Aspergillus/química , Femenino , Masculino , Inmunoensayo/métodos , Persona de Mediana Edad , Aspergilosis Pulmonar Invasiva/diagnóstico , Adulto , Líquido del Lavado Bronquioalveolar/microbiología , Líquido del Lavado Bronquioalveolar/química , Anciano , Anciano de 80 o más AñosRESUMEN
One of the standard assays for the fungal pathogen Cryptococcus neoformans is the glucuronoxylomannan (GXM) ELISA. This assay utilizes monoclonal antibodies targeted against the critical virulence factor, the polysaccharide (PS) capsule. GXM ELISA is one of the most used assays in the field used for diagnosis of cryptococcal infection, quantification of PS content, and determination of binding specificity for antibodies. Here we present three variations of the GXM ELISA used by our group-indirect, capture, and competition ELISAs. We have also provided some history, perspective, and notes on these methods, which we hope will help the reader choose, and implement, the best assay for their research.While it has long been referred to as the GXM ELISA, we also suggest a name update to better reflect our updated understanding of the polysaccharide antigens targeted by this assay. The Cryptococcal PS ELISA is a more accurate description of this set of methodologies and the antigens they measure. Finally, we discuss the limitations of this assay and put forth future plans for expanding the antigens assayed by ELISA.
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Criptococosis , Cryptococcus neoformans , Ensayo de Inmunoadsorción Enzimática , Polisacáridos , Ensayo de Inmunoadsorción Enzimática/métodos , Cryptococcus neoformans/inmunología , Criptococosis/diagnóstico , Criptococosis/microbiología , Criptococosis/inmunología , Polisacáridos/análisis , Polisacáridos/inmunología , Humanos , Antígenos Fúngicos/inmunología , Antígenos Fúngicos/análisis , Polisacáridos Fúngicos/inmunología , Polisacáridos Fúngicos/análisis , Anticuerpos Monoclonales/inmunología , Anticuerpos Antifúngicos/inmunologíaRESUMEN
BACKGROUND: Due to a delay in diagnosis by conventional techniques and high mortality, the development of a standardised and rapid non-culture-based technique is an unmet need in pulmonary, gastrointestinal, and disseminated forms of mucormycosis. Though limited studies have been conducted for molecular diagnosis, there are no established serologic tests for this highly fatal infection. OBJECTIVE: To develop and evaluate an indirect in-house enzyme-linked immunosorbent assay (ELISA) utilising antigens of Rhizopus arrhizus for detecting anti-Rhizopus antibodies (IgG and IgM) in sera of patients with mucormycosis. METHODS: We extracted both secretory and mycelial Rhizopus antigens using standardised protocols. Bradford assay was used for protein quantification. We then standardised an indirect ELISA using R. arrhizus mycelial and secretory antigens (10.0 µg/mL in bicarbonate buffer pH 9.2) for detecting anti-Rhizopus IgG and IgM antibodies in patient sera. We included patients with mucormycosis, other fungal infections, and healthy controls. Antibody index value (E-value) was calculated for each patient sample. RESULTS: Asparagine broth culture filtrate utilising 85% ammonium sulphate salt fractionation and mycelial homogenate grown in yeast extract peptone dextrose (YPD) broth precipitated with trichloroacetic acid (TCA) yielded a large amount of good-quality protein for the assay. We included 55 patients with mucormycosis (rhino-orbito-cerebral mucormycosis [ROCM, n = 39], pulmonary [n = 15], gastrointestinal [n = 1]), 24 with other fungal infections (probable aspergillosis [n = 14], candidiasis [n = 10]), and healthy controls (n = 16). The sensitivity of the antibody test for diagnosing mucormycosis ranged from 83.6-92.7% for IgG and 72.7-87.3% for IgM, with a specificity of 91.7-92.5% for IgG and 80-82.5% for IgM. The sera from patients with other fungal infections and healthy individuals did not show significant cross-reactivity. CONCLUSION: The detection of anti-Rhizopus IgG antibody performed significantly better in comparison to IgM-based ELISA for diagnosing both ROCM (sensitivity of 84.6% vs. 69.2%) and pulmonary cases (86.6% vs. 80.0%). More extensive studies are required to confirm our findings.
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Anticuerpos Antifúngicos , Antígenos Fúngicos , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G , Inmunoglobulina M , Mucormicosis , Rhizopus , Sensibilidad y Especificidad , Pruebas Serológicas , Mucormicosis/diagnóstico , Mucormicosis/microbiología , Mucormicosis/inmunología , Humanos , Rhizopus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Antígenos Fúngicos/inmunología , Antígenos Fúngicos/análisis , Pruebas Serológicas/métodos , Anticuerpos Antifúngicos/sangre , Inmunoglobulina M/sangre , Inmunoglobulina G/sangre , Femenino , Masculino , Persona de Mediana EdadRESUMEN
Several lateral flow assays (LFA) capable of detecting Aspergillus fumigatus in serum and broncho-alveolar lavage fluid (BALF) within the hour, thereby potentially accelerating the screening process, are now commercially available. We prospectively compared three LFA targeting A. fumigatus on BALF collected from non-surgical intensive care patients between June 2022 and February 2023. The three LFA tested were Sõna Aspergillus galactomannan LFA (Immy), Fungadia Aspergillus antigen (Gadia), and AspLFD (OLM Diagnostics). We compared the results of these LFA with those of the galactomannan (GM) Platelia Aspergillus enzyme immunoassay (Bio-Rad), culture on Sabouraud medium and Aspergillus qPCR. We tested 97 BALF samples from 92 patients. In total 84 BALF samples tested negative with all three LFA, and four BALF samples tested positive with the AspLFD assay only (OLM). Only one BALF sample tested positive with the three LFA. In addition, three BALF samples tested positive only with the GM Platelia immunoassay. Four diagnosis of probable invasive aspergillosis were retained for the 92 patients tested. This prospective series included very few positive samples. From a practical point of view, the LFA from OLM presented the simplest protocol for use.
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Antígenos Fúngicos , Aspergillus fumigatus , Líquido del Lavado Bronquioalveolar , Galactosa , Aspergilosis Pulmonar Invasiva , Mananos , Humanos , Líquido del Lavado Bronquioalveolar/microbiología , Líquido del Lavado Bronquioalveolar/química , Estudios Prospectivos , Galactosa/análogos & derivados , Antígenos Fúngicos/análisis , Mananos/análisis , Masculino , Femenino , Aspergillus fumigatus/aislamiento & purificación , Persona de Mediana Edad , Aspergilosis Pulmonar Invasiva/diagnóstico , Aspergilosis Pulmonar Invasiva/microbiología , Anciano , Adulto , Tamizaje Masivo/métodos , Sensibilidad y Especificidad , Inmunoensayo/métodos , Anciano de 80 o más AñosRESUMEN
PURPOSE: Cancer patients are at heightened risk for invasive aspergillosis (IA), a condition associated with elevated mortality risk. The JF5-based Aspergillus Galactomannoprotein Lateral Flow Device (AspLFD) offers rapid point-of-care testing (POCT) for IA. This study evaluated the diagnostic performance of AspLFD in cancer populations. METHODS: This retrospective study examined cancer patient bronchoalveolar lavage fluid (BALF) and serum samples collected between September 2021 and January 2023. Both AspLFD and galactomannan (GM) assays were conducted, and the results were analysed by two independent researchers. RESULTS: This study included 242 samples from 218 cancer patients, with 58 BALF and 184 serum samples. The overall agreement between AspLFD and GM assay results was 92.1%, with a kappa value of 0.552. AspLFD diagnosed proven/probable IA with a sensitivity and specificity of 91.7% and 95.3%, respectively, whereas GM exhibited sensitivity and specificity values of 83.3% and 93.7%, respectively. There were no statistical differences in the sensitivity and specificity between the two methods (P > 0.05). For serum analyses, AspLFD and GM exhibited similar sensitivity (66.7% vs. 66.7%, P > 0.05) and specificity (98.6% vs. 96.6%, P > 0.05) values. However, the sensitivity of the AspLFD was superior to the GM assay (100% vs. 88.9%) in BALF analyses but the difference was not statistically significant (P > 0.05), with no difference in specificity (83.7% vs. 83.7%, P > 0.05). In the solid-tumour cohort, both the AspLFD and GM assay exhibited high sensitivity (100% for both) and specificity (94.2% vs. 92.8%, P > 0.05). CONCLUSION: The AspLFD demonstrated good performance in diagnosing IA in cancer patients, especially those with solid tumours. The AspLFD is thus an alternative POCT, particularly when GM evaluations are not readily available.
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Aspergillus , Líquido del Lavado Bronquioalveolar , Galactosa , Mananos , Neoplasias , Sensibilidad y Especificidad , Humanos , Estudios Retrospectivos , Neoplasias/complicaciones , Persona de Mediana Edad , Femenino , Masculino , Líquido del Lavado Bronquioalveolar/microbiología , Líquido del Lavado Bronquioalveolar/química , Galactosa/análogos & derivados , Mananos/sangre , Mananos/análisis , Anciano , Aspergillus/aislamiento & purificación , Adulto , Pruebas en el Punto de Atención , Aspergilosis Pulmonar Invasiva/diagnóstico , Anciano de 80 o más Años , Antígenos Fúngicos/sangre , Antígenos Fúngicos/análisisRESUMEN
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.
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Infecciones por VIH , Histoplasmosis , Humanos , Histoplasmosis/diagnóstico , Histoplasma , Estudios Retrospectivos , Argentina/epidemiología , Técnicas para Inmunoenzimas , Antígenos Fúngicos/análisisRESUMEN
OBJECTIVES: To describe the implementation of screening for cryptococcal antigenaemia by point-of-care (POC) serum cryptococcal antigen (CrAg) lateral flow assay, measure the prevalence and factors associated with serum cryptococcal antigenaemia in the routine programmatic setting. DESIGN: Cross-sectional study. SETTING: Seventeen publicly funded antiretroviral therapy (ART) centres in Mumbai, India. PARTICIPANTS: Serum CrAg screening was offered to all adolescents (>10 years of age) and adults with advanced HIV disease (AHD) (CD4 <200 cells/mm3 or with WHO clinical stage III/IV) regardless of symptoms of cryptococcal meningitis. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was to describe the implementation of serum CrAg screening and secondary outcome was to measure the prevalence of serum cryptococcal antigenaemia and its risk factors. RESULTS: A total of 2715 patients with AHD were tested for serum CrAg by POC assay. Of these, 25 (0.9%) had a CrAg positive result. Among CrAg-positive patients, only one had symptoms. Serum CrAg positivity was 3.6% (6/169) and 1.6% (6/520) among those presenting with CD4 <100 cells/mm3 in the treatment naïve and treatment experienced group, respectively. On multivariable analysis, CD4 count <100 cells/mm3 (OR: 2.3, 95% CI 1.01 to 5.3; p=0.05) and people living with HIV who were treatment naïve (OR: 2.5, 95% CI 1.04 to 6.0; p=0.04) were significantly associated with a positive serum CrAg result. Lumbar puncture was obtained in 20/25 patients within 4 days (range: 1-4 days) of positive serum CrAg result and one person was confirmed to have meningitis. All serum CrAg-positive patients who had a negative cerebrospinal fluid CrAg were offered pre-emptive therapy. CONCLUSIONS: Implementation of a POC CrAg assay was possible with existing ART centre staff. Initiation of pre-emptive therapy and management of cryptococcal antigenaemia are operationally feasible at ART centres. The Indian National AIDS Control Programme may consider reflexive CrAg screening of all AHD patients with CD4 <100 cells/mm3.
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Cryptococcus , Infecciones por VIH , Adulto , Adolescente , Humanos , Prevalencia , Estudios Transversales , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Pruebas en el Punto de Atención , Antígenos Fúngicos/análisis , India/epidemiología , Recuento de Linfocito CD4RESUMEN
BACKGROUND: Diagnosing progressive disseminated histoplasmosis (PDH) is still challenging in many countries where this disease is highly endemic. Definitive diagnosis is established by culture and/or by cytology/histopathology but both procedures have limited sensitivity and cultures are time-consuming. Antibodies detection by immunodiffusion has a low sensitivity in immunocompromised individuals. Commercially available antigen detection assays have high sensitivity in PDH cases; however, they are expensive and only performed in few laboratories. AIMS: To describe the potential use of a novel ELISA for antibodies testing and a dot blot assay for antigen testing for diagnosing PDH using the recombinant 100 kDa protein of Histoplasma capsulatum (Hcp100) and their polyclonal antibodies as novel reagents, respectively. METHODS: Serum and urine samples from a cohort of patients with HIV/AIDS and proven PDH were studied for the detection of anti-Hcp100 antibodies by ELISA and Hcp100 antigen by dot blot, respectively. Sensitivity, specificity and cross-reactions with other diseases were estimated for each assay and compared with those obtained using histoplasmin (HMN) as a reagent for antibodies detection by ELISA and immunodiffusion, and using a commercial antigenuria test. RESULTS: Antibodies detection by the Hcp100 ELISA demonstrated 78.6% sensitivity and 88.4% specificity, versus 85.7% sensitivity and 81.0% specificity for the HMN ELISA and 26.1% sensitivity and 100% specificity for the immunodiffusion assay. Antigen detection by the Hcp100 dot blot demonstrated 89.3% sensitivity and 97.0% specificity versus 82.1% sensitivity and 90.9% specificity for the commercial test. CONCLUSION: The immunoassays described herein based on Hcp100 would be a valuable screening tool for diagnosing PDH.
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Síndrome de Inmunodeficiencia Adquirida , Histoplasmosis , Humanos , Histoplasmosis/diagnóstico , Histoplasma , Antígenos Fúngicos/análisis , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
BACKGROUND: Meningitis remains an important cause of morbi-mortality in adults in sub-Saharan Africa. Data on the etiological investigation of meningitis in adults in Mozambique is limited and most studies were conducted in southern Mozambique. Identification of the etiology of meningitis in adults are crucial to guide prevention and treatments strategies. In this study, we determine the burden of fungal and bacterial meningitis among adults at the three largest hospitals in Mozambique. METHOD: We performed analysis of data from the routine sentinel surveillance system for meningitis in Mozambique from January 2016 to December 2017. Cerebrospinal fluid (CSF) samples were collected from eligible adults (≥18 years old) who met World Health Organization (WHO) case definition criteria for Meningitis. All samples were tested by cryptococcal antigen (CrAg) lateral flow assay (LFA), culture and triplex real-time polymerase chain reaction (qPCR) assay and all patients were tested for human immunodeficiency virus (HIV) using the national algorithm for HIV testing. RESULTS: Retrospective analysis of 1501 CSF samples from adults clinically suspected of meningitis revealed that 10.5% (158/1501) were positive for bacterial and fungal meningitis. Of these 158 confirmed cases, the proportion of Cryptococcal meningitis and pneumococcal meningitis was38.6% (95% CI: 31.0% to 46.7%) and 36.7% (95% CI: 29.2% to 44.7%), respectively. The other bacterial agents of meningitis identified include Neisseria meningitidis (8.9%; 14/158), Escherichia coli (6.3%; 10/158), Haemophilus influenzae (5.1%; 8/158) and S. aureus (4.4%; 7/158), which represent (24.7%; 39/158) of the total confirmed cases. CONCLUSION: Altogether, our findings show a high burden of Cryptococcal meningitis among adults in Mozambique, especially in people living with HIV, followed by pneumococcal meningitis. Our findings suggest that rollout of CrAg Lateral Flow Assay in the health system in Mozambique for early detection of cryptococcus neoformans is necessary to improve overall patient care.
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Cryptococcus neoformans , Cryptococcus , Infecciones por VIH , Meningitis Criptocócica , Meningitis Neumocócica , Adolescente , Adulto , Antígenos Fúngicos/análisis , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Hospitales , Humanos , Meningitis Criptocócica/diagnóstico , Meningitis Criptocócica/epidemiología , Mozambique/epidemiología , Estudios Retrospectivos , Staphylococcus aureusRESUMEN
Invasive pulmonary aspergillosis (IPA) is a life-threatening disease that affects mainly immunocompromised hosts. Galactomannan testing from serum and bronchoalveolar lavage fluid (BALF) represents a cornerstone in diagnosing the disease. Here, we evaluated the diagnostic performance of the novel Aspergillus-specific galactomannoprotein (GP) enzyme-linked immunosorbent assay (ELISA; Euroimmun Medizinische Labordiagnostika) compared with the established Platelia Aspergillus GM ELISA (GM; Bio-Rad Laboratories) for the detection of Aspergillus antigen in BALF. Using the GP ELISA, we retrospectively tested 115 BALF samples from 115 patients with clinical suspicion of IPA and GM analysis ordered in clinical routine. Spearman's correlation statistics and receiver operating characteristics (ROC) curve analysis were performed. Optimal cutoff values were determined using Youden's index. Of 115 patients, 1 patient fulfilled criteria for proven IPA, 42 for probable IPA, 15 for putative IPA, 10 for possible IPA, and 47 did not meet criteria for IPA. Sensitivities and specificities for differentiating proven/probable/putative versus no IPA (possible excluded) were 74% and 96% for BALF GP and 90% and 96% for BALF GM at the manufacturer-recommended cutoffs. Using the calculated optimal cutoff value of 12 pg/mL, sensitivity and specificity of the BALF GP were 90% and 96%, respectively. ROC curve analysis showed an area under the curve (AUC) of 0.959 (95% confidence interval [CI] of 0.923 to 0.995) for the GP ELISA and an AUC of 0.960 (95% CI of 0.921 to 0.999) for the GM ELISA for differentiating proven/probable/putative IPA versus no IPA. Spearman's correlation analysis showed a strong correlation between the ELISAs (rho = 0.809, P < 0.0001). The GP ELISA demonstrated strong correlation and test performance similar to that of the GM ELISA and could serve as an alternative test for BALF from patients at risk for IPA.
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Aspergilosis Pulmonar Invasiva , Antígenos Fúngicos/análisis , Aspergillus , Líquido del Lavado Bronquioalveolar , Ensayo de Inmunoadsorción Enzimática , Humanos , Aspergilosis Pulmonar Invasiva/diagnóstico , Mananos/análisis , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: Cryptococcal meningitis constitutes a significant source of mortality in the developing world. Annually, approximately 625 000 deaths occur worldwide among patients with human immunodeficiency virus (HIV) infection. This study aims to assess the cost-effectiveness of implementing cryptococcal antigen lateral flow assay (CRAG-LFA) screening in Brazil compared with the current practice. METHODS: An economic evaluation using a Monte Carlo microsimulation was conducted, considering the perspective of the Brazilian Public Health System, to calculate the cost-effectiveness of 4 diagnosis tests: (1) CRAG-LFA, (2) the cryptococcal antigen latex agglutination (CRAG-LA) test, (3) India ink, and (4) nontracking as a baseline. The time horizon comprised 1 year for the intervention and 5 years for the budgetary impact analysis. Two primary effectiveness outcomes were considered: years of life and quality-adjusted life-years. RESULTS: CRAG-LFA has extended dominance vis à vis CRAG-LA and India ink. CRAG-LFA would cost $418.46 more than CRAG-LA for the treatment of each symptomatic patient living with HIV, with an incremental cost effectiveness ratio of $2478.75/quality-adjusted life year. The budgetary impact analysis estimated that the incorporation of CRAG-LFA would have an additional cost of $1 959 236.50 in 5 years. CONCLUSIONS: These findings suggest that, for patients living with HIV in the Brazilian Public Health System, the adoption of CRAG-LFA screening is cost-effective compared with the use of CRAG-LA and India ink. It represents an opportunity to prevent cryptococcal meningitis and its mortality in Brazil.
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Infecciones Oportunistas Relacionadas con el SIDA , Cryptococcus , Infecciones por VIH , Meningitis Criptocócica , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Antígenos Fúngicos/análisis , Brasil/epidemiología , Análisis Costo-Beneficio , VIH , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico , Humanos , Meningitis Criptocócica/diagnóstico , Meningitis Criptocócica/prevención & controlRESUMEN
Hepatopancreatic microsporidiosis (HPM) is an infectious shrimp disease caused by the microsporidian Enterocytozoon hepatopenaei (EHP). In recent years, the widespread occurrence of EHP poses a significant challenge to the shrimp aquaculture industry. Early, rapid and accurate diagnosis of EHP infection is very much essential for the control of HPM crop-related losses. Loop-mediated isothermal amplification (LAMP) is a robust, sensitive, cost-effective disease diagnostic technique. Here, we demonstrate an improved, simple, closed-tube, colorimetric EHP LAMP diagnostic assay. LAMP assay was illustrated with the specific EHP spore wall protein (SWP) gene primers. Naked eye visual detection of LAMP amplicons was achieved using Hydroxy naphthol blue (HNB) or Phenol red dye without opening the tubes. This LAMP assay is efficient in detecting the EHP pathogen in all clinical samples include shrimp hepatopancreas, FTA card samples, feces, pond water, and soil. Also, the elution of EHP DNA from FTA cards was demonstrated within 17 min using a simple dry bath. In clinical evaluation, the visual LAMP assay established 100% diagnostic sensitivity and 100% diagnostic specificity. The visual LAMP assay is rapid, can detect the EHP pathogen within 40 min using a simple dry bath, and does not require any expensive instruments and technical proficiency. In conclusion, this visual LAMP protocol is a user-friendly, specific assay that can be conceivably operated at the farm-site/ resource-limited settings by the farmer himself with simple equipment.
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Antígenos Fúngicos/análisis , Enterocytozoon/aislamiento & purificación , Proteínas Fúngicas/análisis , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Enterocytozoon/genéticaRESUMEN
INTRODUCTION: Cryptococcosis remains a leading cause of meningitis and mortality among people living with HIV (PLHIV) worldwide. We sought to evaluate laboratory-based cryptococcal antigen (CrAg) reflex testing and a clinic-based point-of-care (POC) CrAg screening intervention for preventing meningitis and mortality among PLHIV in South Africa. METHODS: We conducted a prospective pre-post intervention study of adults presenting for HIV testing in Umlazi township, South Africa, over a 6-year period (2013-2019). Participants were enrolled during 3 phases of CrAg testing: CrAg testing ordered by a clinician (clinician-directed testing, 2013-2015); routine laboratory-based CrAg reflex testing for blood samples with CD4 ≤100 cells/mm3 (laboratory reflex testing, 2015-2017); and a clinic-based intervention with POC CD4 testing and POC CrAg testing for PLHIV with CD4 ≤200 cells/mm3 with continued standard-of-care routine laboratory reflex testing among those with CD4 ≤100 cells/mm3 (clinic-based testing, 2017-2019). The laboratory and clinical teams performed serum CrAg by enzyme immunoassay and lateral flow assay (Immy Diagnostics, Norman, OK). We followed up participants for up to 14 months to compare associations between baseline CrAg positivity, antiretroviral therapy and fluconazole treatment initiation, and outcomes of cryptococcal meningitis, hospitalization, and mortality. RESULTS: Three thousand one hundred five (39.4%) of 7877 people screened were HIV-positive, of whom 908 had CD4 ≤200 cells/mm3 and were included in the analyses. Laboratory reflex and clinic-based testing increased CrAg screening (P < 0.001) and diagnosis of CrAg-positive PLHIV (P = 0.011). When compared with clinician-directed testing, clinic-based CrAg testing showed an increase in the number of PLHIV diagnosed with cryptococcal meningitis (4.5% vs. 1.5%; P = 0.059), initiation of fluconazole preemptive therapy (7.2% vs. 2.5%; P = 0.010), and initiation of antiretroviral therapy (96.8% vs. 91.3%; P = 0.012). Comparing clinic-based testing with laboratory reflex testing, there was no significant difference in the cumulative incidence of cryptococcal meningitis (4.5% vs. 4.1%; P = 0.836) or mortality (8.1% vs. 9.9%; P = 0.557). CONCLUSIONS: Laboratory reflex and clinic-based CrAg testing facilitated the diagnosis of HIV-associated cryptococcosis and fluconazole initiation but did not reduce cryptococcal meningitis or mortality. In this nonrandomized cohort, clinical outcomes were similar between laboratory reflex testing and clinic-based POC CrAg testing.
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Antígenos Fúngicos/análisis , Cryptococcus/inmunología , Infecciones por VIH/complicaciones , Meningitis Criptocócica/diagnóstico , Sistemas de Atención de Punto , Adulto , Antifúngicos/uso terapéutico , Femenino , Fluconazol/uso terapéutico , Humanos , Masculino , Meningitis Criptocócica/complicaciones , Meningitis Criptocócica/tratamiento farmacológico , Meningitis Criptocócica/prevención & controlRESUMEN
BACKGROUND: Aspergillus species meet the most important group of invasive fungal diseases (IFD) in immunosuppressed patients. Galactomannan is a polysaccharide antigen located in the wall structure of Aspergillus. The most commonly used method for antigen detection is enzyme-linked immunoassay (ELISA). Aspergillus galactomannan lateral flow assay (LFA) constitutes one of the new methods in the diagnosis of invasive aspergillosis (IA). The goal of this study was to demonstrate efficacy of LFA in our patients and to compare it to synchronous ELISA results. METHODS: Galactomannan antigen was examined using both LFA and ELISA in serum samples taken from patients who were followed up in our haematology clinic. All patients are classified in subgroups as 'proven', 'probable' and 'possible' patients according to the last EORTC / MSG guideline. Patients who met the 'proven' IA criteria were included in the study as the gold standard. RESULTS: A total of 87 patients were included in the study. Majority of patients had acute myeloid leukaemia (AML) (56.3%). Eleven (12.6%) were in 'proven' IA group. LFA test showed a superior diagnostic performance compared with ELISA (LFAAUC = 0.934 vs ELISAAUC = 0.545; p < .001). The LFA had a sensitivity of 90.9% and a specificity of 90.8% for '0.5 ODI' in predicting IA (PPV = 55.8%; NPV = 98.6%; p < .001). CONCLUSION: The most important finding of this study is that the specificity of LFA was found to be higher for cut-off value of 0.5. It is recommended to combine the methods in many studies to provide a better early diagnosis for IA.
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Aspergilosis/diagnóstico , Aspergillus , Mananos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Antígenos Fúngicos/análisis , Antígenos Fúngicos/sangre , Antígenos Fúngicos/inmunología , Aspergillus/inmunología , Aspergillus/aislamiento & purificación , Líquido del Lavado Bronquioalveolar/microbiología , Pruebas Diagnósticas de Rutina/métodos , Ensayo de Inmunoadsorción Enzimática , Femenino , Galactosa/análogos & derivados , Humanos , Huésped Inmunocomprometido , Infecciones Fúngicas Invasoras/diagnóstico , Leucemia Mieloide/complicaciones , Masculino , Mananos/análisis , Mananos/inmunología , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
Prompt and reliable diagnosis of invasive pulmonary aspergillosis (IPA) is essential for early initiation of antifungal therapy. We evaluated bronchoalveolar lavage (BAL) fluid IMMY Sona Aspergillus lateral-flow assay (IMMY LFA) in 92 individuals with suspected pulmonary infection. Sensitivity and specificity (vs. host factor but no IPA) of BAL IMMY LFA for diagnosis of IPA in individuals with any European Organisation for Research and Treatment of Cancer-defied "host factor" were 67% and 85%, respectively. Performance appeared better in individuals with renal transplantation (100%, 100%), compared to those with hematological malignancy and/or allogenic stem cell transplantation (70%, 78%). We found BAL IMMY LFA to be a convenient and useful addition to our diagnostic armory for IPA. LAY ABSTRACT: We evaluated a new test for diagnosing invasive pulmonary aspergillosis from bronchoscopy samples. We tested 92 people and found that it was 67% sensitive and 85% specific (compared to diagnosis according to a set of internationally recognised criteria). We found this test convenient and useful.
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Antígenos Fúngicos/análisis , Líquido del Lavado Bronquioalveolar/microbiología , Cromatografía de Afinidad/métodos , Cromatografía de Afinidad/normas , Aspergilosis Pulmonar Invasiva/diagnóstico , Anciano , Aspergillus/química , Cromatografía de Afinidad/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas en el Punto de Atención/normas , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
Early diagnosis of invasive aspergillosis (IA) is facilitated by detection of galactomannan (GM) in serum and bronchoalveolar lavage fluid (BALF) using an enzyme-linked immunosorbent assay (ELISA). Although accurate, false positive results have been reported with these tests in numerous contexts. We report for the first time the occurrence of false positive GM ELISA due to nocardiosis, initially in a clinical sample of BALF from a patient with pulmonary nocardiosis, and subsequently corroborated by in vitro reactivity of 26% of tested isolates. Since patients at risk for IA are also at risk for nocardiosis, this finding has important clinical implications. LAY SUMMARY: Early diagnosis of aspergillosis has been facilitated by the routine use of antibody-based detection of galactomannan in various bodily fluids. We report for the first time the occurrence of false positive results of this assay in the context of nocardiosis.
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Antígenos Fúngicos/análisis , Líquido del Lavado Bronquioalveolar/microbiología , Ensayo de Inmunoadsorción Enzimática/normas , Reacciones Falso Positivas , Aspergilosis Pulmonar Invasiva/diagnóstico , Mananos/análisis , Anciano , Antígenos Fúngicos/sangre , Aspergillus/química , Galactosa/análogos & derivados , Humanos , Aspergilosis Pulmonar Invasiva/sangre , Masculino , Mananos/sangre , Nocardiosis/sangre , Nocardiosis/diagnóstico , Sensibilidad y EspecificidadRESUMEN
A commercial Aspergillus galactomannan antigen (GMA) enzyme linked immunosorbent assay (ELISA) is used to support a diagnosis of systemic aspergillosis in dogs. In human patients, false positive results have been associated with administration of medications derived from molds. We sought to determine the effect of administration of a commercially available oral probiotic nutraceutical that contained Aspergillus-derived ingredients on serum and urine Aspergillus GMA levels in dogs by conducting a prospective, cross-over study. Galactomannan index (GMI) was measured on the solubilized probiotic nutraceutical and was positive (GMI ≥ 0.5) with a mean of 7.91. Serum and urine galactomannan indices were measured in 10 healthy dogs before (day 0) and after 1 week (day 7) of probiotic nutraceutical administration, then again 2 weeks after the probiotic nutraceutical was discontinued (day 21). Median (range) serum GMI were 0.19 (0.08-0.62), 0.22 (0.07-1.15) and 0.17 (0.14-0.63) at day 0, 7 and 21, respectively. Two of 10 dogs developed positive GMI (≥0.5) results after probiotic nutraceutical administration; however, no significant changes were noted over the study period. Median (range) urine GMI results were 0.06 (0.04-0.22), 0.07 (0.05-0.41) and 0.06 (0.03-0.16) at day 0, 7 and 21, respectively. A trend towards an increase urine GMI was noted between day 0 and 7 (P = 0.18), and decrease was noted between day 7 and 21 (P = 0.09). Administration of probiotics containing Aspergillus-derived ingredients to dogs did not reliably result in elevated Aspergillus GMA levels.