RESUMEN

Leishmaniasis is a significant public health concern, with dogs as the primary reservoir in urban scenarios and facilitating transmission. Diagnosing infected dogs is a crucial step for public health interventions, and the development of new diagnostic platforms can significantly enhance efforts in various regions worldwide. Given the limited availability of diagnostic methods in Colombia, this study evaluates the effectiveness of an Indirect Enzyme-Linked Immunosorbent Assay (ELISA) based on the recombinant protein rLicNTPDase-2 to detect Leishmania in infected dogs. Serum samples were collected from dogs in both endemic and non-endemic areas and classified as natural standards based on prior parasitological diagnoses. The results revealed 24 true positives (TP) and 9 true negatives (TN). Subsequently, the test was then validated with samples from symptomatic and asymptomatic animals, alongside the standards, yielding a specificity of 96 %, a sensitivity of 81 %, efficiency of 90.6 %, a positive predictive value of 92.8 %, and a negative predictive value of 89.6 %. The positive likelihood ratio (RV+) was 20, while the negative likelihood ratio (RV-) was 0.19, indicating high relevance and a robust clinical utility. The area under the curve (AUC) was 1.00, suggesting that the test has excellent discriminatory ability, significantly deviating from the reference diagonal. This is further supported by the significant difference(p < 0.0001) between TN and TP results determined by Fisher's exact test. Involving 163 animals showed 47 % positive and 46 % negative results with a significant difference (p < 0.05) in the mean optical density (OD) values between positive and negative samples. These findings indicate that the ELISA test effectively differentiates between positive and negative samples based on OD values. This study suggests that ELISA based on the recombinant antigen rLicNTPDase-2 could serve as a viable alternative for the serodiagnosis of leishmaniasis in canines in Colombia.

RESUMEN

Serological tests are critical tools in the fight against infectious disease. They detect antibodies produced during an adaptive immune response against a pathogen with an immunological reagent, whose antibody binding characteristics define the specificity and sensitivity of the assay. While pathogen proteins have conveniently served as reagents, their performance is limited by the natural grouping of specific and non-specific antibody binding sites, epitopes. An attractive solution is to build synthetic proteins that only contains pathogen-specific epitopes, which could theoretically reach 100% specificity. However, the genesis of de novo proteins remains a challenge. To address the uncertainty of producing a synthetic protein, we have repurposed the beta barrel of fluorescent proteins into a receptacle that can receive several epitope sequences without compromising its ability to be expressed. Here, two versions of a multiepitope protein were built using the receptacle that differ by their grouping of epitopes specific to the parasite Trypanosoma cruzi, the causative agent for Chagas disease. An evaluation of their performance as the capture reagent in ELISAs showed near-complete agreement with recommended diagnostic protocols. The results suggest that a single assay could be developed for the diagnosis of Chagas disease and that this approach could be applied to other diseases.

RESUMEN

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi, is an important public health problem, occurring mainly in Latin America. The disease has a major social and economical effect, negatively impacting the life of the infected individuals, and bringing great costs to public health. An early and accurate diagnosis is essential for administration of early treatment. In addition, prognostic tests may aid disease management, decreasing hospitalization costs. However, the serological diagnostic scenario for CD still faces several challenges, making the development of new diagnostic kits a pressing matter. Facing this scenario, several researchers have expanded efforts in developing and testing new antigens, such as recombinant proteins and recombinant multiepitope proteins, with promising results. These recombinant antigens offer several advantages, such as improved sensitivity and specificity, in addition to facilitated scaling. Also, it has been possible to observe a rising number of studies using ELISA and point-of-care platforms, employing these antigens in the past few years. Among them, recombinant proteins were the most applied antigens, demonstrating great capacity to discriminate between positive and negative samples. Although fewer in number, recombinant multiepitope proteins also demonstrated an improved diagnostic performance. Indeed, a great number of studies employing these antigens showed sensitivity and specificity values above 90%, greatly impacting diagnostic accuracy. Nevertheless, despite the good results found, it is still possible to observe some bottlenecks in the development of new antigens, such as the scarcity of tests with sera from the acute phase and the variability of results in different geographic areas. In this sense, aiming to contribute to control and health programs, the continuous search for a more accurate serological diagnosis is essential, both for the acute and chronic phases of the disease.

RESUMEN

BACKGROUND: Chagas disease (CD), a neglected parasitic disease caused by Trypanosoma cruzi, poses a significant health threat in Latin America and has emerged globally because of human migration. Trypanosoma cruzi infects humans and over 100 other mammalian species, including dogs, which are important sentinels for assessing the risk of human infection. Nonetheless, the serodiagnosis of T. cruzi in dogs is still impaired by the absence of commercial tests. In this study, we investigated the diagnostic accuracy of four chimeric recombinant T. cruzi IBMP antigens (IBMP-8.1, IBMP-8.2, IBMP-8.3, and IBMP-8.4) for detecting anti-T. cruzi antibodies in dogs, using latent class analysis (LCA). METHODS: We examined 663 canine serum samples, employing indirect ELISA with the chimeric antigens. LCA was utilized to establish a latent variable as a gold standard for T. cruzi infection, revealing distinct response patterns for each antigen. RESULTS: The IBMP (Portuguese acronym for the Molecular Biology Institute of Paraná) antigens achieved area under the ROC curve (AUC) values ranging from 90.9% to 97.3%. The highest sensitivity was attributed to IBMP-8.2 (89.8%), while IBMP-8.1, IBMP-8.3, and IBMP-8.4 achieved 73.5%, 79.6%, and 85.7%, respectively. The highest specificity was observed for IBMP-8.4 (98.6%), followed by IBMP-8.2, IBMP-8.3, and IBMP-8.1 with specificities of 98.3%, 94.4%, and 92.7%, respectively. Predictive values varied according to prevalence, indicating higher effectiveness in endemic settings. CONCLUSIONS: Our findings underscore the remarkable diagnostic performance of IBMP-8.2 and IBMP-8.4 for the serodiagnosis of Trypanosoma cruzi in dogs, representing a promising tool for the diagnosis of CD in dogs. These chimeric recombinant antigens may not only enhance CD surveillance strategies but also hold broader implications for public health, contributing to the global fight against this neglected tropical disease.

Asunto(s)

Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Enfermedad de Chagas , Enfermedades de los Perros , Ensayo de Inmunoadsorción Enzimática , Sensibilidad y Especificidad , Pruebas Serológicas , Trypanosoma cruzi , Animales , Perros , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/veterinaria , Enfermedad de Chagas/parasitología , Trypanosoma cruzi/inmunología , Trypanosoma cruzi/genética , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/parasitología , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Pruebas Serológicas/métodos , Pruebas Serológicas/veterinaria , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Anticuerpos Antiprotozoarios/sangre , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética

RESUMEN

Background: The integration of diagnostic methods holds promise for advancing the surveillance of malaria transmission in both endemic and non-endemic regions. Serological assays emerge as valuable tools to identify and delimit malaria transmission, serving as a complementary method to rapid diagnostic tests (RDT) and thick smear microscopy. Here, we evaluate the potential of antibodies directed against peptides encompassing the entire amino acid sequence of the PvMSP-1 Sal-I strain as viable serological biomarkers for P. vivax exposure. Methods: We screened peptides encompassing the complete amino acid sequence of the Plasmodium vivax Merozoite Surface Protein 1 (PvMSP-1) Sal-I strain as potential biomarkers for P. vivax exposure. Here, immunodominant peptides specifically recognized by antibodies from individuals infected with P. vivax were identified using the SPOT-synthesis technique followed by immunoblotting. Two 15-mer peptides were selected based on their higher and specific reactivity in immunoblotting assays. Subsequently, peptides p70 and p314 were synthesized in soluble form using SPPS (Solid Phase Peptide Synthesis) and tested by ELISA (IgG, and subclasses). Results: This study unveils the presence of IgG antibodies against the peptide p314 in most P. vivax-infected individuals from the Brazilian Amazon region. In silico B-cell epitope prediction further supports the utilization of p314 as a potential biomarker for evaluating malaria transmission, strengthened by its amino acid sequence being part of a conserved block of PvMSP-1. Indeed, compared to patients infected with P. falciparum and uninfected individuals never exposed to malaria, P. vivax-infected patients have a notably higher recognition of p314 by IgG1 and IgG3.

Asunto(s)

Anticuerpos Antiprotozoarios , Biomarcadores , Malaria Vivax , Proteína 1 de Superficie de Merozoito , Plasmodium vivax , Humanos , Malaria Vivax/inmunología , Malaria Vivax/sangre , Malaria Vivax/parasitología , Malaria Vivax/transmisión , Malaria Vivax/diagnóstico , Proteína 1 de Superficie de Merozoito/inmunología , Plasmodium vivax/inmunología , Biomarcadores/sangre , Anticuerpos Antiprotozoarios/inmunología , Anticuerpos Antiprotozoarios/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina G/sangre , Adulto , Femenino , Masculino , Persona de Mediana Edad , Péptidos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Adulto Joven , Adolescente , Secuencia de Aminoácidos

RESUMEN

Serodiagnosis methods have been used as platforms for diagnostic tests for many diseases. Due to magnetic nanoparticles' properties to quickly detach from an external magnetic field and particle size effects, these nanomaterials' functionalization allows the specific isolation of target analytes, enhancing accuracy parameters and reducing serodiagnosis time. Superparamagnetic iron oxide nanoparticles (MNPs) were synthesized and functionalized with polyethylene glycol (PEG) and then associated with the synthetic Leishmaniosis epitope. This nano-peptide antigen showed promising results. Regarding Tegumentary leishmaniasis diagnostic accuracy, the AUC was 0.8398 with sensibility 75% (95CI% 50.50 - 89.82) and specificity 87.50% (95CI% 71.93 - 95.03), and Visceral leishmaniasis accuracy study also present high performance, the AUC was 0.9258 with sensibility 87.50% (95CI% 63.98 - 97.78) and specificity 87.50% (95CI% 71.93 - 95.03). Our results demonstrate that the association of the antigen with MNPs accelerates and improves the diagnosis process. MNPs could be an important tool for enhancing serodiagnosis.

Asunto(s)

Ensayo de Inmunoadsorción Enzimática , Polietilenglicoles , Sensibilidad y Especificidad , Humanos , Ensayo de Inmunoadsorción Enzimática/métodos , Polietilenglicoles/química , Antígenos de Protozoos/inmunología , Leishmaniasis/diagnóstico , Nanopartículas Magnéticas de Óxido de Hierro/química , Anticuerpos Antiprotozoarios/sangre

RESUMEN

Syphilis is a significant public health concern worldwide. According to the 2020 estimates, nearly 7.1 million new cases of syphilis have been reported globally, with over 30 % of these cases reported from American nations, particularly Brazil. Concerns have been raised regarding the susceptibility of specific groups to syphilis due to challenges and vulnerabilities that place these groups at a higher risk of infections or complications in the treatment outcomes. The present study aimed to compare the seroprevalence and the factors associated with syphilis among such high-risk groups. The study was designed as a cross-sectional one and was conducted with pregnant women, people living with HIV (PLHIV), people living with tuberculosis (PLTB), indigenous and healthy populations in Mato Grosso do Sul, Brazil. The study was conducted between June 2019 and August 2022, during which the included patients were subjected to treponemal and non-treponemal serological assays. The study also included a survey conducted through a self-reported questionnaire to collect information regarding the participants' demographics and sexual behaviors. A total of 550 samples were collected, with 110 participants in each of the five groups. The results of the study revealed that the seroprevalence of Treponema pallidum infection in pregnant women, PLHIV, PLTB, indigenous and healthy populations of the study region was 10 % (n = 11/110), 41.81 % (n = 46/110), 17.27 % (n = 19/110), 5.45 % (n = 6/110), and 8.18 % (n = 9/110), respectively. Homosexual orientation (p = 0.04) and a history of sexually transmitted infection (STI) (p = 0.01) were associated with the seroprevalence of T. pallidum infection in PLHIV. However, no such associations were noted in the remaining four groups. The seroprevalence of T. pallidum infection was observed to vary significantly among the different high-risk groups, which highlighted the persistent concern of syphilis, particularly among vulnerable populations. These findings underscore the significance of focused interventions and public health strategies customized to the specific requirements of each of the groups evaluated in the present study to decrease the number of cases of syphilis and thereby prevent future complications in patients with other serious infections.

Asunto(s)

Sífilis , Treponema pallidum , Humanos , Sífilis/epidemiología , Brasil/epidemiología , Estudios Seroepidemiológicos , Femenino , Adulto , Estudios Transversales , Treponema pallidum/inmunología , Masculino , Embarazo , Adulto Joven , Persona de Mediana Edad , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones , Adolescente , Factores de Riesgo , Tuberculosis/epidemiología , Conducta Sexual

RESUMEN

Chagas disease, caused by the protozoa Trypanosoma cruzi, continues to be a serious public health problem in Latin America, worsened by the limitations in its detection. Given the importance of developing new diagnostic methods for this disease, the present review aimed to verify the number of publications dedicated to research on peptides that demonstrate their usefulness in serodiagnosis. To this end, a bibliographic survey was conducted on the PubMed platform using the keyword "peptide" or "epitope" combined with "Chagas disease" or "Trypanosoma cruzi"; "diagno*" or "serodiagnosis" or "immunodiagnosis", without period restriction. An increasing number of publications on studies employing peptides in ELISA and rapid tests assays was verified, which confirms the expansion of research in this field. It is possible to observe that many of the peptides tested so far originate from proteins widely used in the diagnosis of Chagas, and many of them are part of commercial tests developed. In this sense, as expected, promising results were obtained for several peptides when tested in ELISA, as many of them exhibited sensitivity and specificity values above 90%. Furthermore, some peptides have been tested in several studies, confirming their diagnostic potential. Despite the promising results observed, it is possible to emphasize the need for extensive testing of peptides, using different serological panels, in order to confirm their potential. The importance of producing an effective assay capable of detecting the clinical stages of the disease, as well as new immunogenic antigens that enable new serological diagnostic tools for Chagas disease, is evident.

Asunto(s)

Enfermedad de Chagas , Ensayo de Inmunoadsorción Enzimática , Péptidos , Trypanosoma cruzi , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/sangre , Humanos , Trypanosoma cruzi/inmunología , Péptidos/inmunología , Péptidos/química , Ensayo de Inmunoadsorción Enzimática/métodos , Pruebas Inmunológicas/métodos , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/sangre , Pruebas Serológicas/métodos

RESUMEN

The diagnosis of human leptospirosis is mainly based on serological assays. Since the extraction by N-butanol has only been studied as an antigen for the diagnosis of cattle leptospirosis, this study aimed to investigate the feasibility of the N-butanol preparation for the diagnosis of human leptospirosis and compare it with sonicated and thermo-resistant antigens in IgM dot-blot test. Paired serum samples from 147 laboratory-confirmed leptospirosis cases were tested. The control group consisted of 148 serum samples from healthy individuals and nonleptospirosis cases. N-butanol antigens from serovar Copenhageni (ButC3) and serovar Patoc (ButP3) showed reactivity with antileptospiral antibodies from patients with confirmed leptospirosis. In the acute phase, sensitivities of IgM dot-blot assay with ButC3 and ButP3 antigens were 47.6% and 51.0%, respectively. In the convalescent phase, sensitivities were 95.9% (ButC3) and 93.2% (ButP3), and no significant differences were observed among the IgM dot-blot tests with other antigens. The specificity of the IgM dot-blot test with ButC3 antigen was good (92.6%), but with ButP3 (83.1%), it was significantly lower than with the other tests. The IgM dot-blot test described in this study is simple to perform and presents reliable visual results. Antigens prepared by N-butanol proved to be valuable diagnostic markers of leptospirosis.

Asunto(s)

Leptospira , Leptospirosis , Animales , Bovinos , Humanos , 1-Butanol , Butanoles , Antígenos Bacterianos , Ensayo de Inmunoadsorción Enzimática/métodos , Anticuerpos Antibacterianos , Leptospirosis/diagnóstico , Inmunoglobulina M , Sensibilidad y Especificidad

RESUMEN

The objective of this study was to validate an indirect enzyme-linked immunoassay (iELISA) using the recombinant proteins, malate dehydrogenase (MDH) and superoxide dismutase (SOD) [CuZn], as antigens and to evaluate its ability to discriminate antibodies produced by vaccination from those induced by infection in the diagnosis of bovine brucellosis. Sera from six groups were evaluated: G1 - culture-positive animals (52 serum samples) (naturally infected); G2 - non-vaccinated animals (28 serum samples) positive in RBT (Rose Bengal test) and 2ME (2-mercaptoethanol test) selected from brucellosis-positive herds; G3 - animals from a brucellosis-free area (32 serum samples); G4 - S19 vaccinated heifers (114 serum samples); G5 - RB51 vaccinated heifers (60 serum samples); G6 - animals inoculated with inactivated Yersinia enterocolitica O:9 (42 serum samples). Diagnostic sensitivity (DSe) and diagnostic specificity (DSp) were estimated using the frequentist approach and the confidence interval (CI) (95%) calculated by the Clopper-Pearson (exact) method. The DSe for iELISA_MDH in the G1 group was 71.7% (CI 95%: 57.6-83.2%) and for the G2 100.0% (CI 95%: 87.7-100.0%), whereas the DSp was 84.4% in the G3 (CI 95%: 67.2-94.7%). For the iELISA_SOD the DSe was estimated 67.3% for the G1 (CI 95%: 52.9-79.7%) and 71.4% for G2 (CI 95%: 51.3-86.8%), while the DSp for G3 was 87.5% (CI 95%: 71.0-96.5%). iELISA_MDH and iELISA_SOD showed potential to be used in the diagnosis of infected animals, increasing the range of serological tests available for the diagnosis of bovine brucellosis, with the advantage of being S-LPS-free. However, none of the tests could differentiate between infection and vaccination.

Asunto(s)

Brucelosis Bovina , Brucelosis , Animales , Bovinos , Femenino , Malato Deshidrogenasa , Ensayo de Inmunoadsorción Enzimática/métodos , Brucelosis/diagnóstico , Brucelosis/veterinaria , Pruebas Serológicas/métodos , Anticuerpos Antibacterianos , Sensibilidad y Especificidad

RESUMEN

Objectives: This study evaluated the performance of recombinant receptor binding domain (RBD) protein-based enzyme-linked immunosorbent assays (RBD-ELISAs) for detecting anti-SARS-CoV-2 immunoglobulin (Ig) G and IgM antibodies. Methods: In this study, 705 sera from SARS-CoV-2-infected individuals and 315 sera from healthy individuals were analyzed. Results: The RBD-ELISA IgG exhibited high specificity (99.1%) and moderate sensitivity (48.0%), with an overall diagnostic accuracy of 73.5%. RBD-ELISA IgM demonstrated specificity at 94.6% and sensitivity at 51.1%, with an accuracy of 72.8%. Both assays displayed improved performance when analyzing samples collected 15-21 days post-symptom onset, achieving sensitivity and accuracy exceeding 88% and 90%, respectively. Combining RBD-ELISA IgG and IgM in parallel analysis enhanced sensitivity to 98.6% and accuracy to 96.2%. Comparing these RBD-ELISAs with commercially available tests, the study found overlapping sensitivity and similar specificity values. Notably, the combined RBD-ELISA IgG and IgM showed superior performance. Cross-reactivity analysis revealed low false-positive rates (4.4% for IgG, 3.7% for IgM), primarily with viral infections. Conclusion: This research underscores the potential of RBD-based ELISAs for COVID-19 diagnosis, especially when assessing samples collected 15-21 days post-symptom onset and utilizing a parallel testing approach. The RBD protein's immunogenicity and specificity make it a valuable tool for serodiagnosis, offering an alternative to polymerase chain reaction-based methods, particularly in resource-limited settings.

RESUMEN

Introducción: El test del Venereal Diseases Research Laboratory es una prueba serológica, no treponémica, cuyo resultado reactivo es útil en el diagnóstico de sífilis. Sin embargo, no es específica, pues resulta reactiva debido a múltiples causas. Objetivo: Caracterizar a los pacientes que acudieron a consulta con serología reactiva, según variables de interés para el estudio. Materiales y métodos: Se realizó un estudio clínico, descriptivo y transversal en el Policlínico Docente Aquiles Espinoza Salgado, del municipio Las Tunas. El universo fue de 232 pacientes con serología reactiva durante el período de enero de 2018 a diciembre de 2022. Se estudiaron las variables: edad, sexo, motivo de realización de la serología, orientación sexual, causas de test reactivo y criterios diagnósticos en casos de test reactivo debido a sífilis. La información obtenida se presentó en tablas y los resultados se mostraron en porcientos. Resultados: Predominaron los heterosexuales (93,5 %), el chequeo preoperatorio como motivo de realización del test (24,6 %), el sexo masculino (53 %), el grupo de edad entre 25 y 59 años (66,4 %) y la unificación de los tres criterios para el diagnóstico de sífilis (56,8 %). El 53,9 % de los test dieron sífilis. Conclusiones: Se caracterizaron algunas variables en pacientes con test reactivo, destacándose que en la mayoría de ellos la causa fue sífilis. El test se realizó, fundamentalmente, debido a causas no referidas a sífilis. De igual manera, el criterio diagnóstico prevaleciente para confirmar sífilis fue la unificación de los tres criterios.

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Introduction: The Venereal Diseases Research Laboratory test is a nontreponemal serological test, whose reactive result is useful in the diagnosis of syphilis. However, it is not specific as it is reactive due to multiple causes. Objective: To characterize the patients who attended the consultation with reactive serology according to variables of interest for the study. Materials and methods: A clinical, descriptive, cross-sectional study was conducted in the Teaching Policlinic Aquiles Espinoza Salgado in the municipality of Las Tunas, Cuba. The universe was 232 patients with reactive serology during the period from January 2018 to December 2022. The variables studied were: age, sex, reason for serology, sexual orientation, causes of reactive test and diagnostic criteria in cases of reactive test due to syphilis. The information obtained was presented in tables and the results were shown in percentages. Results: There was a predominance of heterosexuals (93,5%), preoperative check-up as the reason for performing the test (24,6%), male sex (53%), age group between 25 and 59 years (66,4%), and unification of the three criteria for the diagnosis of syphilis (56,8%). 53,9% of the tests showed syphilis. Conclusions: Some variables were characterized in patients with a reactive test, highlighting that in most of them the cause was syphilis. The test was performed mainly due to causes not related to syphilis. Likewise, the prevailing diagnostic criterion for confirming syphilis was the unification of the three criteria.

RESUMEN

The objective was to identify the conditions of birth of children of women living with HIV in the period between 2009 and 2019, at the Regional Maternal and Child Hospital of Imperatriz (MA). Cross-sectional, quantitative, documentary study, with descriptive analysis of the data and carried out in a reference maternity hospital between August 2020 and July 2021. Information from the medical records of HIV-positive pregnant women and their newborn children was included. The results collected 314 medical records, of which 195 were eligible. Regarding the birth conditions of the newborns, in 56.41% the rapid test was negative; 72.82% used post-birth prophylaxis; 75.38% did not receive breast milk; 68.2% received vaccines at birth; 40.51% did not use any medication. 20.51% of the mothers were between 36 and 40 years old; 59.48% did not live in the municipality surveyed; 23.6% were housewives; 65.64 were multipara women; 46.15% were diagnosed with HIV during pregnancy; 67.17% had no coinfections; 82.05% underwent prenatal care; 60.51% used intrapartum prophylaxis; and 77.43% underwent cesarean section. The prenatal and childbirth follow-up of most of these women living with HIV reflected positively on the conditions of birth of their children, being an important strategy, aiming at the non-vertical transmission and prevention of the disease in children (AU).

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Objetivou-se identificar as condições de nascimento de filhos de mulheres vivendo com HIV no período compreendido entre 2009 e 2019, no Hospital Regional Materno Infantil de Imperatriz (MA). Estudo transversal, quantitativo, documental, com análise descritiva dos dados e realizado em maternidade de referência entre os meses de agosto de 2020 e julho de 2021. Incluíram-se informações dos prontuários das gestantes soropositivas para HIV e de seus filhos recém-nascidos. Os resultados levantaram 314 prontuários, destes, 195 eram elegíveis. Sobre as condições de nascimento dos recém-nascidos, em 56,41% o teste rápido foi negativo; 72,82% usaram profilaxia pós-nascimento; 75,38% não receberam leite materno; 68,2% receberam vacinas logo ao nascer; 40,51% não faziam uso de nenhuma medicação; 20,51% das mães tinham entre 36 a 40 anos; 59,48% não residiam no município pesquisado; 23,6% eram donas de casa; 65,64 eram multigestas; 46,15% receberam o diagnóstico de HIV na gestação; 67,17% não tinham coinfecções; 82,05% realizaram o pré-natal; 60,51% fizeram uso da profilaxia intraparto; e 77,43% fizeram cesariana. O acompanhamento no pré-natal e parto da maioria dessas mulheres vivendo com HIV refletiu positivamente nas condições de nascimento de seus filhos, sendo uma importante estratégia, visando a não transmissão vertical e prevenção da doença nas crianças (AU).

Asunto(s)

Humanos , Femenino , Embarazo , Recién Nacido , Serodiagnóstico del SIDA , Transmisión Vertical de Enfermedad Infecciosa

RESUMEN

Rapid Diagnostic Tests (RDT) are useful to identify syphilis cases, particularly for hard-to-reach populations and if laboratory services are scarce. However, RDT performance may be suboptimal. We aimed to assess the sensitivity and specificity of a syphilis RDT using well-characterized blood donors' samples. We categorized samples from 811 blood donors into five groups: 1 - Samples with reactive Chemiluminescence (QML), FTA-Abs, and VDRL; 2 - Samples with reactive QML and FTA-Abs, and nonreactive VDRL; 3 - Samples with reactive QML, and nonreactive for other markers (false-positives); 4 - Controls with nonreactive QML; and 5 - Samples reactive for HIV, with nonreactive QML. Sensitivity was tested in groups 1 (overall and according to VDRL titers) and 2; specificity was tested in groups 3‒5. The RDT had high specificity, even in samples reactive for HIV. The sensitivity was high (91.9%) in samples with reactive VDRL but varied between 75.0%‒100% according to VDRL titers. The overall sensitivity was lower (81.3%) in samples with reactive FTA-Abs and nonreactive VDRL. The RDT is a useful tool to detect active syphilis but may be more limited for cases with very early or remote infection, or those with prior treatment. When higher sensitivity is needed, additional strategies including recurrent testing or laboratory-based tests may be required.

Asunto(s)

Infecciones por VIH , Sífilis , Humanos , Sífilis/diagnóstico , Donantes de Sangre , Prueba de Diagnóstico Rápido , Serodiagnóstico de la Sífilis , Sensibilidad y Especificidad , Infecciones por VIH/diagnóstico

RESUMEN

The performance of a commercial immunofluorescence assay (IFA commercial), an in-house immunofluorescence assay (IFA in-house) and an indirect enzyme-linked immunosorbent assay (ELISA) were evaluated in the detection of antibodies anti-C. burnetii in the serum of Q fever patients and persons without the disease. For the study, seropositive and seronegative samples for Q fever (n = 200) from a serum bank of the Instituto Adolfo Lutz in Brazil were used. Commercial IFA was considered in this study as the gold standard for diagnosing Q fever. The in-house IFA demonstrated good agreement with the commercial test, showing high sensitivity (91%) and specificity (97%) compared to the gold standard, with a Kappa coefficient of 0.8954. The indirect ELISA test showed lower agreement with the gold standard, showing low sensitivity (67%), although the specificity of the technique was high (97%) and the Kappa coefficient was moderate (0.6631). In-house IFA is an excellent alternative for diagnosing Q fever.

RESUMEN

BACKGROUND: visceral leishmaniasis (VL) is a critical public health problem in over ninety countries. The control measures adopted in Brazil have been insufficient when it comes to preventing the spread of this overlooked disease. In this context, a precise diagnosis of VL in dogs and humans could help to reduce the number of cases of this disease. Distinct studies for the diagnosis of VL have used single recombinant proteins in serological assays; however, the results have been variable, mainly in relation to the sensitivity of the antigens. In this context, the development of multiepitope-based proteins could be relevant to solving such problem. METHODS: a chimeric protein (rMELEISH) was constructed based on amino acid sequences from kinesin 39 (k39), alpha-tubulin, and heat-shock proteins HSP70 and HSP 83.1, and tested in enzyme-linked immunosorbent (ELISA) for the detection of L. infantum infection using canine (n = 140) and human (n = 145) sera samples. RESULTS: in the trials, rMELEISH was able to discriminate between VL cases and cross-reactive diseases and healthy samples, with sensitivity and specificity values of 100%, as compared to the use of a soluble Leishmania antigenic extract (SLA). CONCLUSIONS: the preliminary data suggest that rMELEISH has the potential to be tested in future studies against a larger serological panel and in field conditions for the diagnosis of canine and human VL.

RESUMEN

Introdução: os dados epidemiológicos mostram um aumento da população idosa vivendo com HIV/AIDS no Brasil. Esta doença impacta de diferentes formas a vida da pessoa constituindo um desafio para os serviços de saúde. Objetivo: verificar as alterações físicas, emocionais e sociais produzidas pelo HIV/AIDS na vida de idosos. Metodologia: estudo qualitativo com método história oral temática. Realizado no Serviço de Atendimento Especializado (SAE) em HIV/AIDS de uma cidade do Oeste Catarinense com a inclusão de três idosos, duas mulheres e um homem, com média de idade de 66 anos e diagnóstico do HIV/AIDS há mais de cinco anos. Foram realizados cinco encontros, dois de observação no domicílio e três para realização da entrevista em profundidade com validação de todas as etapas. A análise dos dados foi realizada por meio da análise de conteúdo temática. A pesquisa foi aprovada no comitê de ética. Resultados e discussão: os idosos apresentaram sintomas físicos decorrentes da imunossupressão sendo o principal deles o emagrecimento, que se constituiu como um sinal de alerta para o diagnóstico do HIV/AIDS. As repercussões emocionais foram o medo e a angústia, mais presentes no momento do diagnóstico e início dos tratamentos. As repercussões sociais estiveram atreladas ao isolamento social, saída de grupos e perda do papel no trabalho. Considerações finais: o HIV/AIDS repercute na vida dos idosos e produz diferentes alterações, quer sejam físicas, emocionais e/ou sociais. Nessa direção, incluir essas demandas no planejamento de ações para esse grupo populacional tornará a assistência à saúde mais resolutiva.(AU)

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Introduction: epidemiological data show an increase in the elderly population living with HIV/AIDS in Brazil. This disease affects people's lives in different ways and constitutes a challenge for health services. Objective: To verify the physical, emotional, and social repercussions caused by HIV/AIDS in the lives of the elderly. Methodology: a qualitative study which used thematic oral history as a method. The research was carried out at the Specialized Care Service (SAE) on HIV/AIDS in a city in western Santa Catarina, which included three elderly diagnosed with HIV/AIDS for more than five years. Two meet-ings were held for approximation and three moments of in-depth interviews with validation in all stages. Data analysis had performed through thematic content analysis, according to Minayo (2014). Results and discussion: The elderly presented physical symptoms resulting from immunosuppression, the main one being weight loss, which constitutes a warning sign for the diagnosis of HIV/AIDS. The emotional repercussions were the fear and anguish most present at the time of diagnosis and the beginning of treatments. The social repercussions were linked to social isolation, leaving groups, and losing the social role of work, being partially reintroduced. Final considerations: HIV/AIDS affects the lives of the elderly, producing different changes, whether physical, emotional, and social, and health services and an interprofessional team need to ensure a broader view of this whole context to qualify assistance.(AU)

Asunto(s)

Anciano , Asistencia a los Ancianos , Envejecimiento , Serodiagnóstico del SIDA , Entrevistas como Asunto

RESUMEN

Syphilis, a sexually transmitted infection, has reemerged in many vulnerable groups around the world. The objective of the current study was to determine the prevalence and incidence of syphilis among people who attended a specialized HIV clinic in Mexico from 2011 to 2015. Databases from the laboratory were analyzed, and the following four groups were formed: people seeking HIV-1 voluntary counseling and testing (VCT), people in prison (PPr), people living with HIV (PLWH), and patients from primary care clinics (others). The diagnosis of syphilis was made using the reverse algorithm; antibody titers were examined to determine the stage of infection. Baseline data were analyzed and, with follow-up information, a retrospective dynamic cohort was formed. Factors associated with the seroprevalence of syphilis and active syphilis were evaluated by the chi-square test. Moreover, risk factors for the incidence of syphilis were described. A total of 81,863 baseline individuals were analyzed. The seroprevalence of syphilis was 9.9% in the VCT group, 8.2% in the PPr group, 37.0% in the PLWH group, and 8.7% in the others group; the prevalence of active syphilis was 1.7-13.1%. A total of 11,124 people were followed up. The incidence (cases per 100 person-years) was 3.5 among the VCT group, 16.0 among the PLWH group, and < 0.1 among both the PPr and others groups, respectively; moreover, the frequency of reinfections was 11.1-24.4%. The high prevalence and incidence of syphilis, active syphilis, and reinfections among men, transgender people, individuals aged 20-39 years, and people with a history of HIV or hepatitis B suggest that it is critical to improve prevention, diagnosis, and treatment measures to stop the reemergence of syphilis. There are also new factors such as methamphetamine use, group sex, or contacting partners over the internet that are associated with syphilis. In addition, HIV preexposure prophylaxis could contribute to the increased incidence of syphilis by providing false security in the prevention of STIs, thereby increasing risky sexual behaviors.

Asunto(s)

Infecciones por VIH , Enfermedades de Transmisión Sexual , Sífilis , Masculino , Humanos , Sífilis/epidemiología , Sífilis/diagnóstico , Sífilis/prevención & control , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Estudios de Cohortes , Incidencia , Estudios Retrospectivos , México/epidemiología , Reinfección , Estudios Seroepidemiológicos , Enfermedades de Transmisión Sexual/epidemiología , Prevalencia

RESUMEN

ABSTRACT Serodiagnosis of strongyloidiasis is usually performed by ELISA for the detection of IgG antibodies due to its high sensitivity and practicality, but its main limitation is a constant source of S. stercoralis antigens. The use of S. venezuelensis as a heterologous source of antigens has facilitated several published studies on the serodiagnosis and epidemiology of human strongyloidiasis. The main objective of this study was to evaluate the diagnostic accuracy of surface cuticle antigens of infective larvae of S. venezuelensis extracted with CTAB detergent (L3-CTAB) in comparison with soluble somatic extracts (L3-SSE) using a panel of sera from immunocompetent and immunocompromised individuals, at three different cut-offs. ROC curve analysis showed that L3-CTAB had an AUC of 0.9926. At the first cut-off value (OD 450 nm = 0.214), sensitivity and specificity were 100% and 90.11%, respectively, with a diagnostic accuracy of 0.93. At a second cut-off value (OD 450 nm = 0.286), sensitivity and specificity were 70% and 100%, respectively, with a diagnostic accuracy of 0.91. However, at an alternative third cut-off value (OD 450 nm = 0.589), sensitivity and specificity were 95% and 97.8%, respectively, with a diagnostic accuracy of 0.97. Using L3-CTAB as an antigenic source, the seropositivity rate in immunocompromised patients was 28.13% (9/32) whereas a seropositivity rate of 34.38% (11/32) was found when L3-SSE was used in ELISA. Therefore, the L3-CTAB is simple and practical to obtain and was found to be highly sensitive and specific.