RESUMO
Urinary tract infections (UTIs) are a common health concern. Urine culture is the "gold standard" for UTI diagnosis but takes 48h. Rapid methods like dipstick tests are used as point-of-care tests. However, their sensitivity and specificity are variable. In this work, a rapid immunochromatographic test (IT) for detecting Escherichia coli in urine was developed, and its performance was evaluated in urine samples from patients with suspected UTI. The "universal lateral flow assay kit" was employed using an E. coli capture antibody. One hundred and five (105) urine samples were analyzed using the IT, dipstick test, and urine culture. The sensitivity of the IT was 74.5%, specificity 88.9%, positive predictive value (PPV) 86.3%, and negative predictive value (NPV) 78.7%. The combination of the IT with the dipstick test increases sensitivity to 94.1%, specificity to 66.7%, PPV to 72.7%, and NPV to 92.3%. Using the IT for detecting E. coli in urine could be a valuable technique for UTI screening, showing better specificity and diagnostic precision but lower sensitivity than the dipstick test. Based on these results, we propose that the combined use of both screening techniques would allow a rapid and more precise diagnosis of UTI, rationalizing the indication for empirical antibiotics.
RESUMO
Laboratory-based case confirmation is an integral part of measles surveillance programmes; however, logistical constraints can delay response. Use of RDTs during initial patient contact could enhance surveillance by real-time case confirmation and accelerating public health response. Here, we evaluate performance of a novel measles IgM RDT and assess accuracy of visual interpretation using a representative collection of 125 sera from the Brazilian measles surveillance programme. RDT results were interpreted visually by a panel of six independent observers, the consensus of three observers and by relative reflectance measurements using an ESEQuant Reader. Compared to the Siemens anti-measles IgM EIA, sensitivity and specificity of the RDT were 94.9% (74/78, 87.4-98.6%) and 95.7% (45/47, 85.5-99.5%) for consensus visual results, and 93.6% (73/78, 85.7-97.9%) and 95.7% (45/47, 85.5-99.5%), for ESEQuant measurement, respectively. Observer agreement, determined by comparison between individuals and visual consensus results, and between individuals and ESEQuant measurements, achieved average kappa scores of 0.97 and 0.93 respectively. The RDT has the sensitivity and specificity required of a field-based test for measles diagnosis, and high kappa scores indicate this can be accomplished accurately by visual interpretation alone. Detailed studies are needed to establish its role within the global measles control programme.
Assuntos
Vírus do Sarampo , Sarampo , Humanos , Brasil/epidemiologia , Testes de Diagnóstico Rápido , Reprodutibilidade dos Testes , Leitura , Imunoglobulina M , Anticorpos Antivirais , Sarampo/diagnóstico , Sarampo/epidemiologiaRESUMO
Clostridioides difficile infection is a public health problem because of it is easily spread; with harmful consequences, it is essential to reduce hospital costs and prevent its dissemination by having a precise diagnosis. The gold standard for its diagnosis is polymerase chain reaction (PCR); however, the technique is not available for all laboratories due to the high cost. New approaches using non-molecular tests to detect C. difficile and toxin A/B production has been proposed to improve cost benefits. The objective of this study is to compare molecular methods (PCR) and rapid methods (immunochromatographic test and enzymatic immunoassay). A series of tests comprising these diagnostic techniques was performed with 50 patients with a clinical diagnosis for Clostridioides difficile on GeneXpert® devices test; a calculation of the sensitivity was executed, followed by a comparison of the efficiency of all techniques. Greater sensitivity was observed in the PCR-based methods (BD MAX™ and BioFire FilmArray®) and the GDH-based assays (RIDASCREEN® and Alere Techlab®). The proposed algorithm represents minor monetary disadvantages but a significant temporal optimization of 10%. Future studies concerning both positive and negative results could be advantageous because of the possibility of calculating more method concordance indexes, such as the specificity and Kappa index, in addition to being able to indicate a monetary profit if the proposed algorithm was applied due to the nonproceeding PCR cases.
Assuntos
Proteínas de Bactérias/análise , Toxinas Bacterianas/análise , Infecções por Clostridium/diagnóstico , Enterotoxinas/análise , Imunoensaio/métodos , Técnicas Imunoenzimáticas/métodos , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Proteínas de Bactérias/genética , Clostridioides difficile/genética , Clostridioides difficile/isolamento & purificação , Fezes/microbiologia , Feminino , Glutamato Desidrogenase/análise , Humanos , Laboratórios , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto JovemRESUMO
Objetivou-se através deste trabalho, determinar a prevalência de cinomose canina no semiárido da Paraíba, através de testes rápidos imunocromatográficos, correlacionando-a com os principais achados clínicos e hematológicos. Foram analisadas 67 fichas de animais em que foram realizados testes rápidos para pesquisa de antígeno em amostras nasais e oculares no período de janeiro a dezembro de 2019. Observou-se que 47% (32/67) dos cães analisados foram positivos para cinomose canina. As variáveis que apresentaram diferença estatística significativa (p<0,05) para a infecção foram animais sem raça definida 60% (21/35), animais não vacinados 70% (29/42), e período seco do ano, sendo o mês de agosto (40%; 13/32), com maior ocorrência. Os principais sistemas afetados foram o respiratório 61% (17/28), oftalmológico 70% (22/31), nervoso 69% (13/19), dermatológico 45% (9/20), e gastrintestinal 42% (6/14). As principais alterações hematológicas foram anemia 66% (23/32), leucopenia 76% (19/25) e linfopenia 48% (15/31). Concluiu-se que foi elevada a ocorrência de cinomose canina em animais com suspeita clínica no Semiárido Paraibano, e animais sem raça definida, não vacinados, no período seco do ano foram mais diagnosticados com a enfermidade.
The objective of this study was to determine the prevalence of distemper canine distemper vírus (CDV) infection in the semi-arid region of Paraíba, using rapid immunochromatographic tests, correlating it with the main clinical and hematological findings. 67 records of animals were analyzed in which rapid tests were performed for antigen research in nasal and ocular from January to December 2019. It was observed that 47% (32/67) of compulsory dogs were positive for canine distemper. The variables that defined difference difference (p <0.05) for infection were mixed breed animals 60% (21/35), unvaccinated animals 70% (29/42), and dry period of the year, being the August (40%; 13/32), with greater occurrence. The main affected systems were the respiratory 61% (17/28), ophthalmological 70% (22/31), nervous 69% (13/19), dermatological 45% (9/20), and gastrointestinal 42% (6/14 )) The main changes were hematological, anemia 66% (23/32), leukopenia 76% (19/25) and lymphopenia 48% (15/31). It was concluded that the occurrence of canine distemper in animals with clinical suspicion in the Semiarid Paraibano was high, and non-vaccinated mixed-breed animals in the dry period of the year were more diagnosed with the disease.
Assuntos
Animais , Cães , Cinomose/diagnóstico , Cinomose/imunologia , Cromatografia de Afinidade/métodos , Cromatografia de Afinidade/veterinária , Cães/sangue , Cães/virologia , Testes HematológicosRESUMO
Objetivou-se através deste trabalho, determinar a prevalência de cinomose canina no semiárido da Paraíba, através de testes rápidos imunocromatográficos, correlacionando-a com os principais achados clínicos e hematológicos. Foram analisadas 67 fichas de animais em que foram realizados testes rápidos para pesquisa de antígeno em amostras nasais e oculares no período de janeiro a dezembro de 2019. Observou-se que 47% (32/67) dos cães analisados foram positivos para cinomose canina. As variáveis que apresentaram diferença estatística significativa (p<0,05) para a infecção foram animais sem raça definida 60% (21/35), animais não vacinados 70% (29/42), e período seco do ano, sendo o mês de agosto (40%; 13/32), com maior ocorrência. Os principais sistemas afetados foram o respiratório 61% (17/28), oftalmológico 70% (22/31), nervoso 69% (13/19), dermatológico 45% (9/20), e gastrintestinal 42% (6/14). As principais alterações hematológicas foram anemia 66% (23/32), leucopenia 76% (19/25) e linfopenia 48% (15/31). Concluiu-se que foi elevada a ocorrência de cinomose canina em animais com suspeita clínica no Semiárido Paraibano, e animais sem raça definida, não vacinados, no período seco do ano foram mais diagnosticados com a enfermidade.
The objective of this study was to determine the prevalence of distemper canine distemper vírus (CDV) infection in the semi-arid region of Paraíba, using rapid immunochromatographic tests, correlating it with the main clinical and hematological findings. 67 records of animals were analyzed in which rapid tests were performed for antigen research in nasal and ocular from January to December 2019. It was observed that 47% (32/67) of compulsory dogs were positive for canine distemper. The variables that defined difference difference (p <0.05) for infection were mixed breed animals 60% (21/35), unvaccinated animals 70% (29/42), and dry period of the year, being the August (40%; 13/32), with greater occurrence. The main affected systems were the respiratory 61% (17/28), ophthalmological 70% (22/31), nervous 69% (13/19), dermatological 45% (9/20), and gastrointestinal 42% (6/14 )) The main changes were hematological, anemia 66% (23/32), leukopenia 76% (19/25) and lymphopenia 48% (15/31). It was concluded that the occurrence of canine distemper in animals with clinical suspicion in the Semiarid Paraibano was high, and non-vaccinated mixed-breed animals in the dry period of the year were more diagnosed with the disease.
Assuntos
Animais , Cães , Cromatografia de Afinidade/veterinária , Cinomose/diagnóstico , Vírus da Cinomose Canina , Cães/virologia , Técnicas de Laboratório Clínico/veterinária , Zona Semiárida , DiagnósticoRESUMO
Objetivou-se através deste trabalho, determinar a prevalência de cinomose canina no semiárido da Paraíba, através de testes rápidos imunocromatográficos, correlacionando-a com os principais achados clínicos e hematológicos. Foram analisadas 67 fichas de animais em que foram realizados testes rápidos para pesquisa de antígeno em amostras nasais e oculares no período de janeiro a dezembro de 2019. Observou-se que 47% (32/67) dos cães analisados foram positivos para cinomose canina. As variáveis que apresentaram diferença estatística significativa (p<0,05) para a infecção foram animais sem raça definida 60% (21/35), animais não vacinados 70% (29/42), e período seco do ano, sendo o mês de agosto (40%; 13/32), com maior ocorrência. Os principais sistemas afetados foram o respiratório 61% (17/28), oftalmológico 70% (22/31), nervoso 69% (13/19), dermatológico 45% (9/20), e gastrintestinal 42% (6/14). As principais alterações hematológicas foram anemia 66% (23/32), leucopenia 76% (19/25) e linfopenia 48% (15/31). Concluiu-se que foi elevada a ocorrência de cinomose canina em animais com suspeita clínica no Semiárido Paraibano, e animais sem raça definida, não vacinados, no período seco do ano foram mais diagnosticados com a enfermidade.(AU)
The objective of this study was to determine the prevalence of distemper canine distemper vírus (CDV) infection in the semi-arid region of Paraíba, using rapid immunochromatographic tests, correlating it with the main clinical and hematological findings. 67 records of animals were analyzed in which rapid tests were performed for antigen research in nasal and ocular from January to December 2019. It was observed that 47% (32/67) of compulsory dogs were positive for canine distemper. The variables that defined difference difference (p <0.05) for infection were mixed breed animals 60% (21/35), unvaccinated animals 70% (29/42), and dry period of the year, being the August (40%; 13/32), with greater occurrence. The main affected systems were the respiratory 61% (17/28), ophthalmological 70% (22/31), nervous 69% (13/19), dermatological 45% (9/20), and gastrointestinal 42% (6/14 )) The main changes were hematological, anemia 66% (23/32), leukopenia 76% (19/25) and lymphopenia 48% (15/31). It was concluded that the occurrence of canine distemper in animals with clinical suspicion in the Semiarid Paraibano was high, and non-vaccinated mixed-breed animals in the dry period of the year were more diagnosed with the disease.(AU)
Assuntos
Animais , Cães , Cinomose/diagnóstico , Cinomose/imunologia , Cromatografia de Afinidade/métodos , Cromatografia de Afinidade/veterinária , Cães/sangue , Cães/virologia , Testes HematológicosRESUMO
BACKGROUND: Leishmaniasis caused by different species of Leishmania affect 98 countries worldwide. Visceral Leishmaniasis (VL) is the mortal clinical presentation of the disease that causes the dead to more than 90% of the patients who suffer it. The diagnosis of VL is made by the direct observation of the parasite in bone marrow, spleen and/or liver aspirates that requires complex proceedings. Therefore, serum samples are submitted to Indirect Immunofluorescence to identify the presence of anti-Leishmania antibodies. Despite the variability in the diagnostic performance of the Immunochromatographic Tests (ICTs), there are many evidences that suggest that ICTs can be used for epidemiological screening. However, in Colombia there are not any evidence about the performance of the ICTs for VL diagnosis, both for human and canine serum samples. Therefore, this study evaluated the diagnostic performance of 4 ICTs for VL (2 ICTs in human sera and 2 ICTs in canine sera) in samples from endemic areas of Colombia. METHODS: We selected a total of 156 human serum samples (82 positive and 74 negative for VL) and 126 canine serum samples (71 positive and 54 negative) diagnosed by in house Indirect Immunofluorescence (IIF). The samples were submitted to the ICTs following the manufacturers' instructions. Statistical analysis was performed to evaluate the diagnostic performance of each ICT in comparison with the IIF. PCR for HSP70 gene and sanger sequencing was performed in samples with negative results for both ICTs. RESULTS: The sensitivity (S) of both ICTs for human samples (Ad-bio Leishmania IgG/IgM Combo Rapid Test and Kalazar Detect™) was 91.5% and specificity (E) were 93.2 and 89.2% respectively, while for the ICTs tested on canine samples (Kalazar Detect™ Rapid Test, Canine and DPP® CVL rapid test) we found S values between 82.9 and 85.7% and E values between 79.6 and 92.6%. We found L. infantum by PCR and sequencing in 2 human samples, and L. braziliensis and L. amazonensis in canine serum samples that were negative by both ICTs. CONCLUSIONS: We conclude that both tests evaluated on human samples have a similar diagnostic performance, while the Kalazar Detect™ Rapid Test, Canine showed a better diagnostic performance than the DPP® CVL rapid test evaluated on canine samples. Also, we suggest that it is necessary to design tests with antigens of the circulating strains to increase its diagnostic utility.
Assuntos
Doenças do Cão/diagnóstico , Imunoensaio/métodos , Leishmaniose Visceral/diagnóstico , Animais , Colômbia , Testes Diagnósticos de Rotina , Doenças do Cão/parasitologia , Cães , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Leishmania infantum/genética , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Reação em Cadeia da Polimerase , Sensibilidade e EspecificidadeRESUMO
The KPC K-SeT immunochromatographic test (Coris BioConcept®, Gembloux, Belgium) has been widely used for detection of KPC in Enterobacteriaceae with reported sensitivities and specificities of 100%. However, to our knowledge, there are no reports of its use in KPC-positive Pseudomonas species. We evaluated the KPC K-SeT test in 36 clinical isolates of Enterobacteriaceae (21 KPC-positive and 15 KPC-negative) and 20 Pseudomonas species (5 KPC-positive and 15 KPC-negative) using conventional PCR for carbapenemase genes as the reference method. The KPC K-SeT test detected 25 out of 26 KPC-positive isolates (96.1%). The undetected isolate was 1 P. aeruginosa bearing the mutation D179Y in the omega loop region of KPC-2 carbapenemase. This mutation was already reported in Enterobacteriaceae as conferring resistance to ceftazidime-avibactam. To our knowledge, this is the first report of evaluation of KPC K-SeT test in KPC-positive P. aeruginosa isolates.
Assuntos
Proteínas de Bactérias/análise , Cromatografia de Afinidade , Enterobacteriaceae/enzimologia , Ensaios Enzimáticos/métodos , Pseudomonas/enzimologia , beta-Lactamases/análise , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Reações Falso-Negativas , Humanos , Reação em Cadeia da Polimerase , Pseudomonas/genética , Pseudomonas/isolamento & purificação , Infecções por Pseudomonas/microbiologia , Sensibilidade e Especificidade , beta-Lactamases/biossíntese , beta-Lactamases/genéticaRESUMO
AIM: We evaluated the accuracy of a commercial rapid immunochromatographic test (rapid test [RT]) for hepatitis A (HA) diagnosis and epidemiological studies. MATERIALS & METHODS: The accuracy of a RT was evaluated in laboratory and in field conditions. Predictive modeling estimated the test performance in a hypothetical population. RESULTS: The RT showed sensitivities of 66-86%, and specificities of 21-100%, depending on the antibody isotype (IgM or IgG) analyzed and prevalence of infection. CONCLUSION: The RT is a good alternative for diagnostic in HA outbreaks. The predictive model indicates that it should not be used alone for HA diagnosis in low prevalence populations. These data can be used in the future to strengthen decision-making during the implementation of rapid diagnostic methods in health services.
Assuntos
Anticorpos Antivirais/sangue , Cromatografia de Afinidade/métodos , Testes Diagnósticos de Rotina/métodos , Hepatite A/diagnóstico , Hepatite A/imunologia , Adolescente , Adulto , Idoso , Brasil , Tomada de Decisão Clínica , Reações Cruzadas , Surtos de Doenças , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Serviços de Saúde , Hepatite A/epidemiologia , Vacinas contra Hepatite A , Humanos , Imunoglobulina G/sangue , Isotipos de Imunoglobulinas , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Adulto JovemRESUMO
BACKGROUND Visceral Leishmaniasis (VL) is an infectious disease that is a significant cause of death among infants aged under 1 year and the elderly in Brazil. Serodiagnosis is a mainstay of VL elimination programs; however, it has significant limitations due to low accuracy. OBJECTIVE This study aimed to evaluate three recombinant Leishmania infantum proteins (rFc, rC9, and rA2) selected from previous proteomics and genomics analyses to develop enzyme-linked immunosorbent assay (ELISA) and immunochromatographic tests (ICT) for the serodiagnosis of human VL (HVL) and canine VL (CVL). METHODS A total of 186 human (70 L. infantum-infected symptomatic, 20 other disease-infected, and 96 healthy) and 185 canine (82 L. infantum-infected symptomatic, 27 L. infantum-infected asymptomatic, and 76 healthy) sera samples were used for antibody detection. FINDINGS Of the three proteins, rA2 (91.5% sensitivity and 87% specificity) and rC9 (95.7% sensitivity and 87.5% specificity) displayed the best performance in ELISA-HVL and ELISA-CVL, respectively. ICT-rA2 also displayed the best performance for HVL diagnosis (92.3% sensitivity and 88.0% specificity) and had high concordance with immunofluorescence antibody tests (IFAT), ELISA-rK39, IT-LEISH®, and ELISAEXT. ICT-rFc, ICT-rC9, and ICT-rA2 had sensitivities of 88.6%, 86.5%, and 87.0%, respectively, with specificity values of 84.0%, 92.0%, and 100%, respectively for CVL diagnosis. MAIN CONCLUSIONS The three antigens selected by us are promising candidates for VL diagnosis regardless of the test format, although the antigen combinations and test parameters may warrant further optimisation.
Assuntos
Animais , Cães , Ensaio de Imunoadsorção Enzimática , Anticorpos Antiprotozoários/sangue , Leishmania infantum/imunologia , Cromatografia de AfinidadeRESUMO
ABSTRACT In this study, the performance of the "RESIST-3 O.K.N. K-SeT" (Coris BioConcept, Gembloux, Belgium) immunochromatographic assay was evaluated in 132 Klebsiella pneumoniae comprising 102 carbapenem resistant and 30 carbapenem susceptible isolates. Genotypically known isolates of Gram negative bacteria (n = 22) including various species were also tested by the assay as controls. The isolates tested by the immunochromatographic assay and also were run PCR for bla KPC, bla IMP, bla VIM, bla NDM, and bla OXA-48. The rates of bla NDM, bla OXA-48, and bla KPC in carbapenem resistant isolates were found at 52.9%, 39.2%, and 2.0%, respectively. Both bla NDM and bla OXA-48 were found in six (5.9%) isolates. The results of the assay showed 100% concordance with those obtained by PCR in 132 K. pneumoniae. The agreement between the two methods was found to be identical at the isolate level. The assay also correctly detected all genotypically known isolates of Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter cloacae, K. pneumoniae carrying bla KPC, bla NDM, and/or bla OXA-48. On the other hand, the assay did not exhibit any cross-reaction in control isolates harboring bla IMP and bla VIM. We conclude that the RESIST-3 O.K.N. K-SeT is a reliable, rapid, and user friendly test and we recommend it for routine diagnostic laboratories.
Assuntos
Humanos , Proteínas de Bactérias/análise , beta-Lactamases/análise , Infecções por Klebsiella/microbiologia , Imunoensaio/métodos , Klebsiella pneumoniae/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Turquia , beta-Lactamases/metabolismo , Carbapenêmicos/farmacologia , Reação em Cadeia da Polimerase , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/química , Antibacterianos/farmacologiaRESUMO
In this study, the performance of the RESIST-3 O.K.N. K-SeT (Coris BioConcept, Gembloux, Belgium) immunochromatographic assay was evaluated in 132 Klebsiella pneumoniae comprising 102 carbapenem resistant and 30 carbapenem susceptible isolates. Genotypically known isolates of Gram negative bacteria (n = 22) including various species were also tested by the assay as controls. The isolates tested by the immunochromatographic assay and also were run PCR for bla KPC, bla IMP, bla VIM, bla NDM, and bla OXA-48. The rates of bla NDM, bla OXA-48, and bla KPC in carbapenem resistant isolates were found at 52.9%, 39.2%, and 2.0%, respectively. Both bla NDM and bla OXA-48 were found in six (5.9%) isolates. The results of the assay showed 100% concordance with those obtained by PCR in 132 K. pneumoniae. The agreement between the two methods was found to be identical at the isolate level. The assay also correctly detected all genotypically known isolates of Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter cloacae, K. pneumoniae carrying bla KPC, bla NDM, and/or bla OXA-48. On the other hand, the assay did not exhibit any cross-reaction in control isolates harboring bla IMP and bla VIM. We conclude that the RESIST-3 O.K.N. K-SeT is a reliable, rapid, and user friendly test and we recommend it for routine diagnostic laboratories.(AU)
RESUMO
Brucellosis is a serious infectious disease that causes significant economic losses in the livestock industry. Its early diagnosis allows an adequate disease control in cattle. DAVIH Laboratories designed a lateral flow immunochromatographic assay using protein A-colloidal gold as a detector reagent (LFIA-PA). The objective of this work was to compare the performance of this assay using protein G-colloidal gold (LFIA-PG) with its performance using protein A-colloidal gold as the detector reagent. The assays were carried out with 20 µL of serum and 130 µL of running buffer. Interpretation of bands was by visual inspection with the naked eye at 15- 20 minutes after sample application. The tests were evaluated with 449 samples of bovine serum (111 positive and 338 negative). The diagnostic sensitivity and specificity, the positive and negative predictive values, and the efficacy of both assays were calculated, and their concordance was estimated by calculating the kappa (k) index. The estimated values of the parameters for LFIA-PG and LFPIA-PA were 100% and 95.2% of diagnostic sensitivity, 96.2% and 97.3% of diagnostic specificity, 89.5% and 92.3% for the positive predictive value, 100% and 98.5% for the negative predictive value, and 97.1% and 96.89% of efficacy, respectively. The concordance between both tests was very good (k = 0.95). It was shown the possibilities of developing a system with LFIA-PG capable of detecting antibodies against Brucella spp. The performance of the test makes possible its use as a screening method in the diagnosis of brucellosis.
RESUMO
In this study, the performance of the "RESIST-3 O.K.N. K-SeT" (Coris BioConcept, Gembloux, Belgium) immunochromatographic assay was evaluated in 132 Klebsiella pneumoniae comprising 102 carbapenem resistant and 30 carbapenem susceptible isolates. Genotypically known isolates of Gram negative bacteria (n=22) including various species were also tested by the assay as controls. The isolates tested by the immunochromatographic assay and also were run PCR for blaKPC, blaIMP, blaVIM, blaNDM, and blaOXA-48. The rates of blaNDM, blaOXA-48, and blaKPC in carbapenem resistant isolates were found at 52.9%, 39.2%, and 2.0%, respectively. Both blaNDM and blaOXA-48 were found in six (5.9%) isolates. The results of the assay showed 100% concordance with those obtained by PCR in 132K. pneumoniae. The agreement between the two methods was found to be identical at the isolate level. The assay also correctly detected all genotypically known isolates of Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter cloacae, K. pneumoniae carrying blaKPC, blaNDM, and/or blaOXA-48. On the other hand, the assay did not exhibit any cross-reaction in control isolates harboring blaIMP and blaVIM. We conclude that the RESIST-3 O.K.N. K-SeT is a reliable, rapid, and user friendly test and we recommend it for routine diagnostic laboratories.
Assuntos
Proteínas de Bactérias/análise , Imunoensaio/métodos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , beta-Lactamases/análise , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Humanos , Klebsiella pneumoniae/química , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Reação em Cadeia da Polimerase , Turquia , beta-Lactamases/metabolismoRESUMO
We standardized an immunochromatographic test (IC) for heat-labile toxin I (LT-I) detection using LT-I antibodies and a specific platform containing the apparatus for application, assembly and cutting. IC detected as little as 62.5ng/mL of purified LT-I toxin and presented 91% sensitivity, 99.5% specificity and 96.0% accuracy, thereby proving to be an excellent point-of-care test for the diagnosis of enterotoxigenic E. coli infection in low-income countries.
Assuntos
Toxinas Bacterianas/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , Diarreia/diagnóstico , Escherichia coli Enterotoxigênica/isolamento & purificação , Enterotoxinas/isolamento & purificação , Infecções por Escherichia coli/diagnóstico , Proteínas de Escherichia coli/isolamento & purificação , Imunoensaio/métodos , Anticorpos Antibacterianos/imunologia , Toxinas Bacterianas/imunologia , Testes Diagnósticos de Rotina/instrumentação , Diarreia/microbiologia , Escherichia coli Enterotoxigênica/metabolismo , Escherichia coli Enterotoxigênica/patogenicidade , Enterotoxinas/imunologia , Proteínas de Escherichia coli/imunologia , Temperatura Alta , Humanos , Imunoensaio/instrumentação , Sensibilidade e EspecificidadeRESUMO
Introdução: A hanseníase é de grande importância para a saúde pública, devido à sua epidemiologia e a seu poder incapacitante. A eficiência no diagnóstico desta doença é limitada. O objetivo deste estudo foi o de analisar o desempenho de um teste rápido imunocromatográfico para hanseníase multibacilar (MB) e paucibacilar (PB), em amostras positivas e negativas pela baciloscopia de raspado dérmico em pacientes diagnosticados com hanseníase, comparando analiticamente com os critérios da Organização Mundial da Saúde (OMS). Métodos: O estudo foi realizado no município de Ji-Paraná/RO, entre 2015 e 2016, sendo avaliados 140 indivíduos. A análise comparativa entre os métodos foi realizada pelo cálculo de sensibilidade e especificidade utilizando o software SPSS®. Foi estimado o índice de Kappa (k) para avaliação da concordância entre os métodos. Valores de p <0,05 foram considerados significativos. Resultados: O índice de concordância entre o teste rápido e a classificação da OMS foi de k= 0,94 (p <0,01). Quando comparado a baciloscopia de indivíduos com hanseníase PB e o teste rápido, foi verificada concordância não significante (k= 0,01; p= 0,59). Comparando a concordância entre a baciloscopia de indivíduos com hanseníase MB e o teste rápido, foi detectado um índice de k= 0,64 (p <0,01). Além disso, sensibilidade de 94% e especificidade de 98% foram detectadas para hanseníase PB. Para hanseníase MB a sensibilidade foi de 95% e a especificidade de 98%. Conclusão: O teste rápido avaliado é uma ferramenta útil, rápida e eficaz no auxílio do diagnóstico da hanseníase. (AU)
Introduction: Leprosy is of great importance for public health because of its epidemiology and disabling power. Efficiency in the diagnosis of this disease is limited. The objective of this study was to evaluate the performance of a rapid immunochromatographic test for multibacillary (MB) and paucibacillary (BP) leprosy, in positive and negative samples by skin smear examination in patients with leprosy, and to compare the rapid test analytically with World Health Organization (WHO) criteria. Methods: The study was conducted in the municipality of Ji-Paraná/RO, Brazil, between 2015 and 2016. In total, 140 individuals were evaluated. For a comparative analysis of the methods, sensitivity and specificity were calculated using SPSS® software. The Kappa (k) index was used to evaluate agreement between the methods. A p-value < 0.05 was considered significant. Results: Regarding agreement between the rapid test and WHO classification, k index was 0.94 (p < 0.01). When skin smear of individuals with BP leprosy was compared to the rapid test, agreement was non-significant (k = 0.01; p = 0.59). For agreement between skin smear of individuals with MB leprosy and the rapid test, a k index of 0.64 (p < 0.01) was detected. In addition, for PB leprosy sensitivity was 94% and specificity was 98%, while for MB leprosy sensitivity was 95% and specificity was 98%. Conclusion: The rapid test is a useful tool, fast and effective in aiding the diagnosis of leprosy. (AU)
Assuntos
Humanos , Hanseníase Multibacilar/diagnóstico , Hanseníase Multibacilar/epidemiologia , Hanseníase Paucibacilar/diagnóstico , Hanseníase Paucibacilar/epidemiologia , Brasil/epidemiologiaRESUMO
We standardized an immunochromatographic test (IC) for heat-labile toxin I (LT-I) detection using LT-I antibodies and a specific platform containing the apparatus for application, assembly and cutting. IC detected as little as 62.5 ng/mL of purified LT-I toxin and presented 91% sensitivity, 99.5% specificity and 96.0% accuracy, thereby proving to be an excellent point-of-care test for the diagnosis of enterotoxigenic E. coli infection in low-income countries.
RESUMO
Abstract Human adenoviruses comprise an important group of etiologic agents that are responsible for various diseases in adults and children, such as respiratory, ocular, gastroenteric, and urinary infections. In immunocompromised and organ-transplanted individuals, these agents can cause generalized infections. Rapid diagnostic methods for detecting these infectious agents are not widely available.The aim of this work was to produce monoclonal and polyclonal anti-adenovirus antibodies to be used in a rapid diagnostic test for respiratory infections.Adenovirus hexons were satisfactorily purified by ultracentrifugation and chromatography. After virus purification, anti-hexon monoclonal antibodies were produced and characterized, following classical methods. Antibodies were specific for adenoviruses 2, 3, 5, and 41. The proposed immunochromatographic test was standardized using colloidal gold.The standardization of the rapid test was sufficient to detect adenovirus antigens (in nasopharyngeal lavage samples) with sensitivity of 100% and specificity of 85% when compared to direct immunofluorescence.The immunochromatographic assay prototype was sufficiently sensitive to detect B (3), C (2 and 5), and F (41) adenovirus samples. Although based on preliminary data, the test demonstrated the same performance as direct immunofluorescence, but with the advantage of being a point-of-care test. Further studies are still needed to confirm its effectiveness in clinical practice.
Assuntos
Humanos , Adenovírus Humanos/classificação , Cromatografia de Afinidade/métodos , Infecções por Adenoviridae/diagnóstico , Infecções por Adenoviridae/virologia , Anticorpos Antivirais/sangueRESUMO
Human adenoviruses comprise an important group of etiologic agents that are responsible for various diseases in adults and children, such as respiratory, ocular, gastroenteric, and urinary infections. In immunocompromised and organ-transplanted individuals, these agents can cause generalized infections. Rapid diagnostic methods for detecting these infectious agents are not widely available. The aim of this work was to produce monoclonal and polyclonal anti-adenovirus antibodies to be used in a rapid diagnostic test for respiratory infections. Adenovirus hexons were satisfactorily purified by ultracentrifugation and chromatography. After virus purification, anti-hexon monoclonal antibodies were produced and characterized, following classical methods. Antibodies were specific for adenoviruses 2, 3, 5, and 41. The proposed immunochromatographic test was standardized using colloidal gold. The standardization of the rapid test was sufficient to detect adenovirus antigens (in nasopharyngeal lavage samples) with sensitivity of 100% and specificity of 85% when compared to direct immunofluorescence. The immunochromatographic assay prototype was sufficiently sensitive to detect B (3), C (2 and 5), and F (41) adenovirus samples. Although based on preliminary data, the test demonstrated the same performance as direct immunofluorescence, but with the advantage of being a point-of-care test. Further studies are still needed to confirm its effectiveness in clinical practice.
Assuntos
Infecções por Adenoviridae/diagnóstico , Infecções por Adenoviridae/virologia , Adenovírus Humanos/classificação , Anticorpos Antivirais/sangue , Cromatografia de Afinidade/métodos , HumanosRESUMO
INTRODUCTION: The present study was designed to assess the occurrence of co-infection or cross-reaction in the serological techniques used for detecting the anti-Leishmania spp., -Babesia canis vogeli and -Ehrlichia canis antibodies in urban dogs from an area endemic to these parasites. METHODS: The serum samples from dogs were tested for the Babesia canis vogeli strain Belo Horizonte antigen and Ehrlichia canis strain São Paulo by immunofluorescence antibody test (IFAT) and by anti-Leishmania immunoglobulin G (IgG) antibody detection to assess Leishmania infection. We used the following four commercial kits for canine visceral leishmaniasis: ELISA, IFAT, Dual Path Platform (DPP) (Bio Manguinhos(r)/FIOCRUZ/MS) and a rK39 RDT (Kalazar Detect Canine Rapid Test; Inbios). RESULTS : Of 96 serum samples submitted to serological assays, 4 (4.2%) were positive for Leishmania as determined by ELISA; 12 (12.5%), by IFAT; 14 (14.6%) by rK39 RDT; and 20 (20.8%), by DPP. Antibodies against Ehrlichia and Babesia were detected in 23/96 (23.9%) and 30/96 (31.2%) samples, respectively. No significant association was identified between the results of tests for detecting Babesia or Ehrlichia and those for detecting Leishmania (p-value>0.05). CONCLUSIONS: In the present study, we demonstrated co-infection with Ehrlichia or Babesia and Leishmania in dogs from Minas Gerais (Brazil); we also found that the serological tests that were used did not cross-react. .