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1.
J Mycol Med ; 34(2): 101481, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38718721

ABSTRACT

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.


Subject(s)
Antigens, Fungal , Aspergillus fumigatus , Bronchoalveolar Lavage Fluid , Galactose , Invasive Pulmonary Aspergillosis , Mannans , Humans , Bronchoalveolar Lavage Fluid/microbiology , Bronchoalveolar Lavage Fluid/chemistry , Prospective Studies , Galactose/analogs & derivatives , Antigens, Fungal/analysis , Mannans/analysis , Male , Female , Aspergillus fumigatus/isolation & purification , Middle Aged , Invasive Pulmonary Aspergillosis/diagnosis , Invasive Pulmonary Aspergillosis/microbiology , Aged , Adult , Mass Screening/methods , Sensitivity and Specificity , Immunoassay/methods , Aged, 80 and over
2.
Mycoses ; 67(5): e13730, 2024 May.
Article in English | MEDLINE | ID: mdl-38712824

ABSTRACT

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.


Subject(s)
Antibodies, Fungal , Antigens, Fungal , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G , Immunoglobulin M , Mucormycosis , Rhizopus , Sensitivity and Specificity , Serologic Tests , Mucormycosis/diagnosis , Mucormycosis/microbiology , Mucormycosis/immunology , Humans , Rhizopus/immunology , Enzyme-Linked Immunosorbent Assay/methods , Antigens, Fungal/immunology , Antigens, Fungal/analysis , Serologic Tests/methods , Antibodies, Fungal/blood , Immunoglobulin M/blood , Immunoglobulin G/blood , Female , Male , Middle Aged
3.
Methods Mol Biol ; 2775: 239-255, 2024.
Article in English | MEDLINE | ID: mdl-38758322

ABSTRACT

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.


Subject(s)
Cryptococcosis , Cryptococcus neoformans , Enzyme-Linked Immunosorbent Assay , Polysaccharides , Enzyme-Linked Immunosorbent Assay/methods , Cryptococcus neoformans/immunology , Cryptococcosis/diagnosis , Cryptococcosis/microbiology , Cryptococcosis/immunology , Polysaccharides/analysis , Polysaccharides/immunology , Humans , Antigens, Fungal/immunology , Antigens, Fungal/analysis , Fungal Polysaccharides/immunology , Fungal Polysaccharides/analysis , Antibodies, Monoclonal/immunology , Antibodies, Fungal/immunology
4.
Eur J Clin Microbiol Infect Dis ; 43(6): 1221-1229, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38625450

ABSTRACT

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.


Subject(s)
Aspergillus , Bronchoalveolar Lavage Fluid , Galactose , Mannans , Neoplasms , Sensitivity and Specificity , Humans , Retrospective Studies , Neoplasms/complications , Middle Aged , Female , Male , Bronchoalveolar Lavage Fluid/microbiology , Bronchoalveolar Lavage Fluid/chemistry , Galactose/analogs & derivatives , Mannans/blood , Mannans/analysis , Aged , Aspergillus/isolation & purification , Adult , Point-of-Care Testing , Invasive Pulmonary Aspergillosis/diagnosis , Aged, 80 and over , Antigens, Fungal/blood , Antigens, Fungal/analysis
5.
Medicina (B Aires) ; 83(6): 863-874, 2023.
Article in English | MEDLINE | ID: mdl-38117705

ABSTRACT

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.


Subject(s)
HIV Infections , Histoplasmosis , Humans , Histoplasmosis/diagnosis , Histoplasma , Retrospective Studies , Argentina/epidemiology , Immunoenzyme Techniques , Antigens, Fungal/analysis
6.
BMJ Open ; 13(6): e070500, 2023 06 22.
Article in English | MEDLINE | ID: mdl-37349096

ABSTRACT

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.


Subject(s)
Cryptococcus , HIV Infections , Adult , Adolescent , Humans , Prevalence , Cross-Sectional Studies , HIV Infections/complications , HIV Infections/epidemiology , HIV Infections/drug therapy , Point-of-Care Testing , Antigens, Fungal/analysis , India/epidemiology , CD4 Lymphocyte Count
7.
Mycoses ; 66(7): 609-620, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37029519

ABSTRACT

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.


Subject(s)
Acquired Immunodeficiency Syndrome , Histoplasmosis , Humans , Histoplasmosis/diagnosis , Histoplasma , Antigens, Fungal/analysis , Enzyme-Linked Immunosorbent Assay
8.
PLoS One ; 17(5): e0267949, 2022.
Article in English | MEDLINE | ID: mdl-35544535

ABSTRACT

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.


Subject(s)
Cryptococcus neoformans , Cryptococcus , HIV Infections , Meningitis, Cryptococcal , Meningitis, Pneumococcal , Adolescent , Adult , Antigens, Fungal/analysis , HIV Infections/complications , HIV Infections/diagnosis , HIV Infections/epidemiology , Hospitals , Humans , Meningitis, Cryptococcal/diagnosis , Meningitis, Cryptococcal/epidemiology , Mozambique/epidemiology , Retrospective Studies , Staphylococcus aureus
9.
PLos ONE ; 17(5): 1-13, maio 11, 2022.
Article in English | RSDM | ID: biblio-1532402

ABSTRACT

Antecedentes: A meningite continua a ser uma causa importante de morbimortalidade em adultos na África Subsaariana. Os dados sobre a investigação etiológica da meningite em adultos em Moçambique são limitados e a maioria dos estudos foram realizados no sul de Moçambique. A identificação da etiologia da meningite em adultos é crucial para orientar estratégias de prevenção e tratamento. Neste estudo, determinamos a carga de meningite fúngica e bacteriana entre adultos nos três maiores hospitais de Moçambique. Método: Realizamos análise de dados do sistema de vigilância sentinela de rotina para meningite em Moçambique de janeiro de 2016 a dezembro de 2017. Amostras de líquido cefalorraquidiano (LCR) foram coletadas de adultos elegíveis (≥18 anos de idade) que atenderam ao caso da Organização Mundial da Saúde (OMS). Critérios de definição para Meningite. Todas as amostras foram testadas por ensaio de fluxo lateral (LFA) de antígeno criptocócico (CrAg), cultura e ensaio triplex de reação em cadeia da polimerase em tempo real (qPCR) e todos os pacientes foram testados para o vírus da imunodeficiência humana (HIV) usando o algoritmo nacional para testes de HIV. Resultados: A análise retrospectiva de 1.501 amostras de LCR de adultos com suspeita clínica de meningite revelou que 10,5% (158/1.501) foram positivas para meningite bacteriana e fúngica. Destes 158 casos confirmados, a proporção de meningite criptocócica e meningite pneumocócica foi de 38,6% (IC 95%: 31,0% a 46,7%) e 36,7% (IC 95%: 29,2% a 44,7%), respectivamente. Os outros agentes bacterianos de meningite identificados incluem Neisseria meningitidis (8,9%; 14/158), Escherichia coli (6,3%; 10/158), Haemophilus influenzae (5,1%; 8/158) e S. aureus (4,4%; 7/ 158), que representam (24,7%; 39/158) do total de casos confirmados. Conclusão: Em conjunto, os nossos resultados mostram uma elevada carga de meningite criptocócica entre adultos em Moçambique, especialmente em pessoas que vivem com VIH, seguida de meningite pneumocócica. As nossas descobertas sugerem que a implementação do Ensaio de Fluxo Lateral CrAg no sistema de saúde em Moçambique para a detecção precoce de Cryptococcus neoformans é necessária para melhorar o atendimento geral ao paciente.


Subject(s)
Humans , Male , Female , Adult , HIV Infections/complications , HIV Infections/diagnosis , HIV Infections/epidemiology , Meningitis, Cryptococcal/diagnosis , Meningitis, Cryptococcal/epidemiology , Cryptococcosis , Cryptococcus neoformans , Meningitis, Pneumococcal , Staphylococcus aureus , Retrospective Studies , Hospitals , Mozambique/epidemiology , Antigens, Fungal/analysis
10.
J Clin Microbiol ; 60(4): e0021522, 2022 04 20.
Article in English | MEDLINE | ID: mdl-35350844

ABSTRACT

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.


Subject(s)
Invasive Pulmonary Aspergillosis , Antigens, Fungal/analysis , Aspergillus , Bronchoalveolar Lavage Fluid , Enzyme-Linked Immunosorbent Assay , Humans , Invasive Pulmonary Aspergillosis/diagnosis , Mannans/analysis , Retrospective Studies , Sensitivity and Specificity
11.
Value Health Reg Issues ; 29: 53-59, 2022 May.
Article in English | MEDLINE | ID: mdl-34801886

ABSTRACT

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.


Subject(s)
AIDS-Related Opportunistic Infections , Cryptococcus , HIV Infections , Meningitis, Cryptococcal , AIDS-Related Opportunistic Infections/diagnosis , AIDS-Related Opportunistic Infections/prevention & control , Antigens, Fungal/analysis , Brazil/epidemiology , Cost-Benefit Analysis , HIV , HIV Infections/complications , HIV Infections/diagnosis , Humans , Meningitis, Cryptococcal/diagnosis , Meningitis, Cryptococcal/prevention & control
12.
J Invertebr Pathol ; 183: 107624, 2021 07.
Article in English | MEDLINE | ID: mdl-34077765

ABSTRACT

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.


Subject(s)
Antigens, Fungal/analysis , Enterocytozoon/isolation & purification , Fungal Proteins/analysis , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , Enterocytozoon/genetics
13.
J Acquir Immune Defic Syndr ; 87(5): 1205-1213, 2021 08 15.
Article in English | MEDLINE | ID: mdl-33990495

ABSTRACT

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.


Subject(s)
Antigens, Fungal/analysis , Cryptococcus/immunology , HIV Infections/complications , Meningitis, Cryptococcal/diagnosis , Point-of-Care Systems , Adult , Antifungal Agents/therapeutic use , Female , Fluconazole/therapeutic use , Humans , Male , Meningitis, Cryptococcal/complications , Meningitis, Cryptococcal/drug therapy , Meningitis, Cryptococcal/prevention & control
14.
Mycoses ; 64(6): 678-683, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33683715

ABSTRACT

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.


Subject(s)
Aspergillosis/diagnosis , Aspergillus , Mannans/blood , Adult , Aged , Aged, 80 and over , Antigens, Fungal/analysis , Antigens, Fungal/blood , Antigens, Fungal/immunology , Aspergillus/immunology , Aspergillus/isolation & purification , Bronchoalveolar Lavage Fluid/microbiology , Diagnostic Tests, Routine/methods , Enzyme-Linked Immunosorbent Assay , Female , Galactose/analogs & derivatives , Humans , Immunocompromised Host , Invasive Fungal Infections/diagnosis , Leukemia, Myeloid/complications , Male , Mannans/analysis , Mannans/immunology , Middle Aged , Sensitivity and Specificity
15.
Med Mycol ; 59(4): 404-408, 2021 Apr 06.
Article in English | MEDLINE | ID: mdl-33479770

ABSTRACT

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.


Subject(s)
Antigens, Fungal/analysis , Bronchoalveolar Lavage Fluid/microbiology , Chromatography, Affinity/methods , Chromatography, Affinity/standards , Invasive Pulmonary Aspergillosis/diagnosis , Aged , Aspergillus/chemistry , Chromatography, Affinity/instrumentation , Female , Humans , Male , Middle Aged , Point-of-Care Testing/standards , Prospective Studies , Sensitivity and Specificity
16.
Med Mycol ; 59(2): 206-209, 2021 Feb 04.
Article in English | MEDLINE | ID: mdl-32944777

ABSTRACT

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.


Subject(s)
Antigens, Fungal/analysis , Bronchoalveolar Lavage Fluid/microbiology , Enzyme-Linked Immunosorbent Assay/standards , False Positive Reactions , Invasive Pulmonary Aspergillosis/diagnosis , Mannans/analysis , Aged , Antigens, Fungal/blood , Aspergillus/chemistry , Galactose/analogs & derivatives , Humans , Invasive Pulmonary Aspergillosis/blood , Male , Mannans/blood , Nocardia Infections/blood , Nocardia Infections/diagnosis , Sensitivity and Specificity
17.
PLoS One ; 15(11): e0242361, 2020.
Article in English | MEDLINE | ID: mdl-33227000

ABSTRACT

We use a 785 nm shifted excitation Raman difference (SERDS) technique to measure the Raman spectra of the conidia of 10 mold species of especial toxicological, medical, and industrial importance, including Stachybotrys chartarum, Penicillium chrysogenum, Aspergillus fumigatus, Aspergillus flavus, Aspergillus oryzae, Aspergillus niger, and others. We find that both the pure Raman and fluorescence signals support the hypothesis that for an excitation wavelength of 785 nm the Raman signal originates from the melanin pigments bound within the cell wall of the conidium. In addition, the major features of the pure Raman spectra group into profiles that we hypothesize may be due to differences in the complex melanin biosynthesis pathways. We then combine the Raman spectral data with neural network models to predict species classification with an accuracy above 99%. Finally, the Raman spectral data of all species investigated is made freely available for download and use.


Subject(s)
Spectrum Analysis, Raman/methods , Spores, Fungal/chemistry , Spores, Fungal/classification , Allergens/analysis , Antigens, Fungal/analysis , Aspergillus , Aspergillus fumigatus , Penicillium chrysogenum , Spores, Fungal/metabolism , Stachybotrys
18.
Vet J ; 265: 105551, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33129555

ABSTRACT

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.


Subject(s)
Antigens, Fungal/analysis , Aspergillosis/veterinary , Aspergillus/immunology , Dog Diseases/microbiology , Mannans/immunology , Probiotics/administration & dosage , Animals , Antigens, Fungal/blood , Antigens, Fungal/urine , Aspergillosis/diagnosis , Dietary Supplements/microbiology , Dog Diseases/diagnosis , Dogs , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Galactose/analogs & derivatives , Male
19.
Sci Rep ; 10(1): 18219, 2020 10 26.
Article in English | MEDLINE | ID: mdl-33106525

ABSTRACT

Central nervous system (CNS) infections cause substantial morbidity and mortality worldwide, with mounting concern about new and emerging neurologic infections. Stratifying etiologies based on initial clinical and laboratory data would facilitate etiology-based treatment rather than relying on empirical treatment. Here, we report the epidemiology and clinical outcomes of patients with CNS infections from a prospective surveillance study that took place between 2013 and 2016 in Singapore. Using multiple correspondence analysis and random forest, we analyzed the link between clinical presentation, laboratory results, outcome and etiology. Of 199 patients, etiology was identified as infectious in 110 (55.3%, 95%-CI 48.3-62.0), immune-mediated in 10 (5.0%, 95%-CI 2.8-9.0), and unknown in 79 patients (39.7%, 95%-CI 33.2-46.6). The initial presenting clinical features were associated with the prognosis at 2 weeks, while laboratory-related parameters were related to the etiology of CNS disease. The parameters measured were helpful to stratify etiologies in broad categories, but were not able to discriminate completely between all the etiologies. Our results suggest that while prognosis of CNS is clearly related to the initial clinical presentation, pinpointing etiology remains challenging. Bio-computational methods which identify patterns in complex datasets may help to supplement CNS infection diagnostic and prognostic decisions.


Subject(s)
Antigens, Bacterial/analysis , Antigens, Fungal/analysis , Antigens, Viral/analysis , Central Nervous System Infections/complications , Communicable Diseases/diagnosis , Aged , Central Nervous System Infections/microbiology , Communicable Diseases/classification , Communicable Diseases/epidemiology , Communicable Diseases/etiology , Data Interpretation, Statistical , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Prognosis , Prospective Studies , Singapore/epidemiology
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