Primoinfección por Toxoplasma gondii en gestantes de Atención Primaria de Salud en La Habana / Primoinfection by Toxoplasma gondii in pregnant women in Primary Health Care in Havana

Introducción: La primoinfección por Toxoplasma gondii adquirida durante el embarazo puede causar manifestaciones clínicas graves en el producto de la gestación, hecho tratable y prevenible. Objetivo: Describir evidencias serológicas de primoinfección por T. gondii en gestantes de Atención Primaria de Salud (APS) en La Habana. Metodología: Se realizó una descripción retrospectiva de resultados serológicos de embarazadas pesquisadas en APS, La Habana, desde 2005 a 2011. Se procesaron 1820 sueros en el Laboratorio Nacional de Referencia de Parasitología del Instituto Pedro Kourí (LNRP-IPK) a través de inmunofluorescencia indirecta (IFI), VIDAS TOXO IgM y Toxo IgG Avidity. A las muestras con títulos de anticuerpos ≥ 1/128 por IFI, se les determinó IgM; si eran positivas, se precisó la avidez de IgG. Resultados: Hubo 1151 (63,2 por ciento) sueros negativos. La mayoría eran gestantes entre 16 y 35 años con un promedio de positividad de 34,1 por ciento, sin diferencias significativas entre los municipios de procedencia. Prevalecieron los títulos de IgG anti-Toxoplasma 1/16-1/64, en gestantes de más de 35 años hubo 120/209 (57,4 por ciento), resultado significativo al compararlo con el grupo menor de 16 años (4/14; 28,5 por ciento). En 58 mujeres aparecieron títulos de IgG ≥ 1/128 (3,1 por ciento), y predominaron las menores de 16 años (2/14; 14,2 por ciento). El 17,2 por ciento de las embarazadas resultó IgG e IgM positivas, aspecto relevante en La Habana Vieja (6,8 por ciento). Se encontraron cifras bajas de avidez en 5/10 (índice < 0,200 IgG), que representó el 0,2 por ciento del total de las gestantes estudiadas. Conclusión: En embarazadas de algunas áreas de salud en La Habana, hubo evidencias de primoinfección por T. gondii(AU)

Introduction: Primoinfection by Toxoplasma gondii acquired during pregnancy can cause severe clinical manifestations in the newborn parameters; it is a treatable and preventable event, though. Objective: To describe serological evidence of primoinfection by T. gondii in pregnant women in Primary Health Care (PHC) in Havana. Methods: A retrospective descriptive study of serological results of pregnant women screened in the PHC, Havana, from 2005 to 2011 was conducted. A total of 1820 sera were processed at the National Reference Laboratory of Parasitology of Pedro Kourí Institute (LNRP-IPK) through indirect immunofluorescence assay (IFA), VIDAS TOXO IgM and Toxo IgG Avidity. Samples with antibody titers ≥ 1/128 by IFA were tested for IgM; if positive, IgG avidity was determined. Results: 1151 sera (63.2%) yielded negative results. Most were pregnant women between 16 and 35 years of age with an average positivity of 34.1 percent, without significant distinction between municipalities of origin. Anti-Toxoplasma IgG titers prevailed 1/16-1/64. In pregnant women over 35 years of age, titers were 120/209 (57.4 percent), a significant result when compared with the group under 16 years of age (4/14; 28.5 percent). IgG titers ≥ 1/128 (3.1 percent) appeared in 5858 women, and those under 16 years of age predominated (2/14; 14.2 percent). IgG and IgM were positive in 17.2 percent of pregnant women, a relevant aspect in Old Havana (6.8 percent). Low levels of avidity were found in 5/10 (index < 0.200 IgG), which represented 0.2 percent of the total number of pregnant women studied. Conclusion: In pregnant women in some health areas in Havana, primoinfection by T. gondii was confirmed(AU)

The direct and indirect effects of the pneumococcal conjugated vaccine on carriage rates in children aged younger than 5 years in Latin America and the Caribbean: a systematic review / Efeitos diretos e indiretos da vacina pneumocócica conjugada no estado de portador em crianças menores de 5 anos, na América Latina e no Caribe: uma revisão sistemática

ABSTRACT Objective To demonstrate the impact of pneumococcal conjugate vaccine in Streptococcus pneumoniae carriage status in children younger than 5 years in Latin America and the Caribbean. Methods A systematic literature review was carried out on the direct and indirect effects of pneumococcal vaccine in the carriage status, after implementation in childhood immunization programs. Studies carried out in children younger than 5 years were selected from the PubMed® and Virtual Health Library databases, and data collected after implementation of pneumococcal vaccine in Latin America and the Caribbean, between 2008 and 2018. Results From 1,396 articles identified, 738 were selected based on titles and abstracts. After duplicate removal, 31 studies were eligible for full-text reading, resulting in 6 publications for analysis. All selected publications were observational studies and indicated a decrease in the carriage and vaccine types, and an increase in the circulation of non-vaccine serotypes, such as 6A, 19A, 35B, 21 and 38. We did not identify changes in the antimicrobial resistance after vaccine implementation. Conclusion A decrease in the carriage status of vaccine types and non-vaccine types was detected. The continuous monitoring of pneumococcal vaccine effect is fundamental to demonstrate the impact of the carriage status and, consequently, of invasive pneumococcal disease, allowing better targeting approaches in countries that included pneumococcal vaccine in their immunization programs. Our study protocol was registered in PROSPERO (www.crd.york.ac.uk/prospero) under number CRD42018096719.

RESUMO Objetivo Demonstrar o impacto das vacinas pneumocócicas conjugadas no estado de portador de Streptococcus pneumoniae em crianças menores de 5 anos na América Latina e no Caribe. Métodos Foi realizada revisão sistemática da literatura sobre os efeitos diretos e indiretos da vacina pneumocócica no estado de portador em crianças menores de 5 anos, após a implantação da vacina nos calendários de imunização infantil. A partir de dados da PubMed®e da Biblioteca Virtual da Saúde, foram selecionados estudos de portador em crianças menores de 5 anos, com dados coletados após implementação da vacina de 2008 a 2018, na América Latina e no Caribe. Resultados Dos 1.396 artigos identificados, 738 foram selecionados mediante leitura de títulos e resumos. Após a extração dos duplicados, 31 foram elegíveis para leitura do texto completo, restando 6 artigos para análise. Todos os estudos selecionados eram observacionais e indicavam diminuição do portador e tipos vacinais, e aumento da circulação de sorotipos não vacinais, como 6A, 19A, 35B, 21 e 38. Não foi observada alteração na resistência antimicrobiana após a introdução da vacina. Conclusão Detectou-se redução no estado de portador, dos tipos vacinais e não vacinais. O monitoramento contínuo do efeito das vacinas pneumocócicas é fundamental, para demonstrar o impacto do estado de portador e, consequentemente, da doença pneumocócica invasiva, permitindo o melhor direcionamento nas ações em saúde para os países que incluíram a vacina no calendário de imunização. Nosso protocolo de estudo foi registrado no PROSPERO (www.crd.york.ac.uk/prospero) sob o número CRD42018096719.

Performance evaluation of an indirect immunofluorescence kit for the serological diagnosis of dengue / Avaliação do desempenho de kit de imunofluorescência indireta para o diagnóstico sorológico de dengue

ABSTRACT Objective: To evaluate the performance of indirect immunofluorescence for serological diagnosis of dengue virus in a population with high prevalence of arboviruses. Methods: Two-hundred serum samples from patients with clinical suspicion of dengue fever were tested by immunoenzymatic and indirect immunofluorescence assay BIOCHIP® mosaic. Specificity, sensitivity and Kappa coefficient were calculated. Discordant samples were tested by polymerase chain reaction for confirmation. Results: Of the 200 samples, 20% were positive and 80% negative for anti-dengue virus IgM antibodies in the immunoenzymatic test. Of the 40 positives, 25% were negative in indirect immunofluorescence. Of these ten discordant results, only 20% were also negative in the polymerase chain reaction (PCR). Of the 160 negatives in the immunoenzymatic test, 5% were positive in indirect immunofluorescence. Of these nine discordant results, 33% were positive in the PCR. The Kappa coefficient was 0.7 (0.572-0.829). Sensitivity and specificity of indirect immunofluorescence were respectively 75% and 94%. For anti-dengue virus IgG antibodies, of the 200 samples, 15.5% were positive and 84.5% were negative in the immunoenzymatic test. Of the 31 positives, 12.9% were negative in indirect immunofluorescence. Of these four discordant results, 25% were negative in the PCR. Of the 169 negatives, 8% were positive in indirect immunofluorescence. Of these 14 discordant results, 64% were also positive in the PCR. The Kappa coefficient was 0.695 (0.563-0.83). Sensitivity and specificity of indirect immunofluorescence were 87.1% and 91.7%, respectively. Conclusion: For diagnosis of acute infection, the immunoenzymatic test is enough, and the use of additional methods is not warranted. Replacing the immunoenzymatic test by indirect immunofluorescence would compromise the sensitivity for IgM. However, indirect immunofluorescence can distinguish three arboviruses simultaneously, an advantage during concomitant epidemics.

RESUMO Objetivo: Avaliar o desempenho da imunofluorescência indireta no diagnóstico sorológico de dengue em uma população com alta prevalência de arboviroses. Métodos: Duzentas amostras de soro de pacientes com suspeita clínica de dengue foram testadas por ensaio imunoenzimático e imunofluorescência indireta mosaico BIOCHIP®. Foram calculados especificidade, sensibilidade e coeficiente Kappa. Nas amostras discordantes, realizou-se reação em cadeia da polimerase como método confirmatório. Resultados: Das 200 amostras, 20% foram positivas e 80% negativas para IgM antivírus da dengue no ensaio imunoenzimático. Das 40 positivas, 25% foram negativas na imunofluorescência indireta. Destas dez negativas, apenas 20% eram também negativas na reação em cadeia da polimerase. Das 160 negativas no ensaio imunoenzimático, 5% foram positivas na imunofluorescência indireta. Por fim, dentre as nove discordantes, 33% tiveram vírus da dengue detectado na reação em cadeia da polimerase. O coeficiente Kappa foi 0,70 (0,57-0,82). Sensibilidade e especificidade por imunofluorescência indireta foram, respectivamente, 75% e 94%. Para IgG antivírus da dengue, de 200 amostras, 15,5% foram positivas e 84,5% negativas no ensaio imunoenzimático. Das 31 positivas, 12,9% foram negativas na imunofluorescência indireta. Destas quatro discordantes, 25% apresentaram vírus da dengue não detectado na reação em cadeia da polimerase. Das 169 negativas, 8% foram positivas na imunofluorescência indireta. Destas, 64% foram positivas também na reação em cadeia da polimerase. O coeficiente Kappa foi 0,695 (0,56-0,83). Sensibilidade e a especificidade por imunofluorescência indireta foram, respectivamente, 87,1% e 91,7%. Conclusão: Ensaio imunoenzimático seria suficiente para diagnóstico sorológico de infecção aguda, não justificando a incorporação da imunofluorescência indireta. Substituir ensaio imunoenzimático pela imunofluorescência indireta poderia comprometer a sensibilidade para IgM. Contudo, a imunofluorescência indireta auxilia diferenciar três arboviroses simultaneamente, sendo vantajoso em epidemias concomitantes.

Comparison between enzyme-linked immunosorbent assay and indirect immunofluorescence for detection of antineutrophil cytoplasmic antibodies / Comparação entre os métodos de ensaio imunoenzimático e imunoflurescência indireta para a pesquisa de anticorpos anticitoplasma de neutrófilos

ABSTRACT Objective To evaluate the performance of enzyme-linked immunosorbent assay and indirect immunofluorescence methods for the detection of antineutrophil cytoplasmic antibodies in a routine clinical laboratory setting. Methods A total of 227 samples were tested by indirect immunofluorescence and enzyme-linked immunosorbent assay with antigen specificity for antiproteinase 3 and antimyeloperoxidase. The proportions of positive samples were compared by McNemar hypotheses and agreement was described by Cohen's Kappa coefficient. Results The agreement of the tests was 96.5%, and the Kappa coefficient obtained was 0.70 (95%CI: 0.50-0.90; p<0.001). Considering indirect immunofluorescence as the gold standard, the sensitivity of the enzyme-linked immunosorbent assay was 0.62 and the specificity was 0.99, with diagnostic accuracy in 96% of cases. Some samples were negative in enzyme-linked immunosorbent assay and positive in indirect immunofluorescence. This situation occurred in all immunofluorescence patterns, but particularly in atypical patterns. Two samples with antiproteinase 3 positivity were considered negative in indirect immunofluorescence. Conclusion The enzyme-linked immunosorbent assay had high specificity but lower sensitivity. The performance of indirect immunofluorescence increases diagnostic sensitivity, while the search for antiproteinase 3 by enzyme-linked immunosorbent assay may also add diagnostic power.

RESUMO Objetivo Avaliar o desempenho das metodologias de ensaio imunoenzimático e imunofluorescência indireta para a detecção de anticorpos anticitoplasma de neutrófilos em um contexto de laboratório clínico de rotina. Métodos Foram testadas 227 amostras pelas metodologias de imunofluorescência indireta e ensaio imunoenzimático com especificidades para anticorpos antiproteinase-3 e antimieloperoxidase. As proporções de amostras positivas foram comparadas por hipóteses de McNemar, e a concordância foi descrita pelo coeficiente Kappa de Cohen. Resultados A concordância dos testes foi 96,5%, e o coeficiente Kappa obtido foi 0,70 (IC95%: 0,50-0,90; p<0,001). Utilizando a imunofluorescência indireta como padrão-ouro, a sensibilidade do ensaio imunoenzimático foi de 0,62 e a especificidade, 0,99, com acurácia diagnóstica em 96% dos casos. Algumas amostras apresentaram resultados negativos por ensaio imunoenzimático e positivos por imunofluorescência. Isso ocorreu em amostras com vários padrões de fluorescência, mas particularmente nos casos com padrões atípicos. Duas amostras com positividade antiproteinase 3 foram consideradas negativas por imunofluorescência. Conclusão Os métodos de ensaio imunoenzimático tiveram alta especificidade, mas sensibilidade inferior. A realização da imunofluorescência indireta aumenta a sensibilidade diagnóstica, ao mesmo tempo que a pesquisa de antiproteinase 3 por ensaio imunoenzimático também pode agregar poder diagnóstico.

Efectividad de los métodos diagnósticos para la detección de ehrlichiosis monocítica humana y canina / Effectivity of diagnostic methods for the detection of human and canine monocytic ehrlichiosis

Resumen La ehrlichiosis es una enfermedad transmitida por la picadura de garrapatas que afecta a perros y humanos, causada por las especies Ehrlichia canis y E. chaffeensis, respectivamente. Estas bacterias son gramnegativas, intracelulares obligadas, de aspecto cocoide a pleomorfo, que infectan los monocitos y desencadenan síntomas como fiebre elevada, anorexia, trombocitopenia, hemorragias, anemia y problemas graves como esplenomegalia, hepatomegalia y meningitis. Para diagnosticar esta enfermedad existen diversos métodos, entre los que se encuentran los hematológicos que evalúan la morfología de los monocitos en búsqueda de mórulas y la serología, que incluye la búsqueda de anticuerpos anti-Ehrlichia, pero que se encuentra limitado debido a la reactividad cruzada que presenta. Por otra parte, el cultivo de especies de Ehrlichia ha resultado ser un método efectivo para la obtención de antígenos y así desarrollar ensayos por inmunofluorescencia indirecta (IFI). El método por reacción de polimerasa en cadena ofrece un diagnóstico definitivo por tener una mayor sensibilidad y especificidad que los otros métodos, al haberse desarrollado cebadores género-específicos, así como especie-específicos. En esta revisión, se discutirán los diversos métodos aplicados al diagnóstico de esta enfermedad, así como las ventajas y desventajas que estos presentan.

Ehrlichiosis is a disease transmitted by tick's bite that affect dogs and humans caused by the species Ehrlichia canis and E. chaffeensis, respectively. These bacteria are obligated intracellular gram negatives, with a cocoid to pleomorph aspect and can infect monocytes and trigger symptoms such as high fever, anorexia, thrombocytopenia, hemorrhages, anemia, and some serious problems such as splenomegaly, hepatomegaly and meningitis. There are several diagnostic tests for ehrlichiosis such as the hematological ones that evaluate the morphology of the monocytes in search of morulae; serological tests that includes the search of anti-Ehrlichia antibodies, although they might be limited due to cross reaction with other species. In other hand, the culture of Ehrlichia species is an effective method to obtain antigens and even develop indirect immunofluorescence assays (IFA). The polymerase chain reaction offers a definitive diagnosis associated to the use of genus-specific and species-specific primers, as well as its increased sensibility and specificity, compared to the others methods. Thus, in this review, we will discuss various methods applied to the diagnosis of this disease, as well as the advantages and disadvantages that these present.

Brotes emergentes de leptospirosis del Amazonas colombiano / Emerging leptospirosis outbreaks in the Colombian Department of Amazonas

Se describe por primera vez una serie de nueve casos con clínica indicativa de leptospirosis en el municipio Puerto Nariño en el departamento Amazonas, Colombia. Se muestran evidencias serológicas de exposición con Rickettsia del grupo de las fiebres manchadas. Los casos fueron clínicamente considerados como síndrome febril de origen desconocido. Se descartó infección por dengue y malaria. El diagnóstico de Leptospira se realizó mediante el método de reacción en cadena de la polimerasa en tiempo real. Igualmente, se detectó la presencia de anticuerpos contra rickettsias del grupo de las fiebres manchadas por inmunofluorescencia Indirecta. Finalmente, se realiza revisión del tema(AU)

A description is provided for the first time of a series of nine cases with a clinical examination suggestive of leptospirosis in the municipality of Puerto Nariño, Department of Amazonas, Colombia. Serological evidence is presented of exposure to Rickettsia, spotted fever group. The cases were clinically considered as febrile syndrome of unknown origin. Infection with dengue or malaria was ruled out. Diagnosis of leptospirosis was achieved by real-time polymerase chain reaction. Additionally, indirect immunofluorescence detected the presence of antibodies against rickettsia, spotted fever group. Finally, a review was conducted about the topic(AU)

Inmunofluorescencia indirecta versus reacción de polimerasa en cadena para el diagnóstico de virus respiratorios en niños ingresados en un hospital de la Región Metropolitana / Indirect immunofluorescence technique versus polymerase chain reaction for the diagnosis of respiratory viruses in children admitted to a hospital in the Metropolitan Region

Resumen Introducción: La temprana detección viral en infecciones respiratorias agudas (IRA) es esencial para establecer una terapia apropiada y prevenir el contagio intrahospitalario. Objetivo: Comparar la eficacia de la técnica de inmunofluorescencia indirecta (IFI) con la reacción de polimerasa en cadena (RPC) para identificar virus respiratorios en niños hospitalizados por IRA. Métodos: Se incluyeron 47 aspirados nasofaríngeos de niños ≤ 2 años con IRA. La IFI incluyó virus respiratorio sincicial (VRS), adenovirus, influenza A y B y parainfluenza. La RPC incluyó, además, la detección de metapneumovirus, enterovirus/rinovirus, bocavirus y coronavirus. Se estimó sensibilidad, especificidad, valor predictor positivo y negativo (VPP/VPN) y correlación kappa para VRS mediante IFI en comparación a la RPC. Resultados: La IFI detectó únicamente VRS (29; 61,7%). La RPC detectó diversos virus, entre ellos VRS en 26 casos (55,3%), seguido por bocavirus (29,8%), enterovirus/ rinovirus (21,3%), adenovirus (14,9%) y parainfluenza (4,3%) entre otros, con 35,5% de co-infección. La IFI presentó sensibilidad: 85,7%, especificidad: 73,6%, VPP: 82,7%, VPN: 77,7% y kappa: 0,5990 (IC 95%; 0,36360,8346) para VRS. Conclusión: La IFI presenta buena sensibilidad, pero moderada especificidad para VRS. Sin embargo, falla en la detección de otros virus respiratorios. La introducción de RPC permitiría mejorar el diagnóstico etiológico de las IRA de origen viral.

Background: Early viral detection in acute respiratory infections (ARI) is essential to establish appropriate therapy and prevent nosocomial transmission. Objective: To compare the efficacy of indirect immunofluorescence technique (IIF) with the polymerase chain reaction (PCR) to identify respiratory viruses in children hospitalized for ARI. Methods: 47 nasopharyngeal aspirates of children ≤ 2 years with ARI were included. IFI included respiratory syncytial virus (RSV), adenovirus, influenza A and B and parainfluenza. PCR also included the detection of metapneumovirus, enterovirus/rhinovirus, bocavirus and coronavirus. Sensitivity, specificity, positive and negative predictive value (VPP/NPV) and kappa correlation for RSV were estimated by IIF compared to PCR. Results: The IIF detected only RSV (29; 61.7%). PCR detected several viruses, including RSV in 26 cases (55.3%), followed by bocavirus (29.8%), rhinovirus/enterovirus (21.3%), adenovirus (14.9%) and parainfluenza (4,3%) among others, with 35.5% of coinfection. The IIF presented sensitivity: 85.7%, specificity: 73.6%, PPV: 82.7%, NPV: 77.7% and kappa: 0.5990 (95% CI, 0.3636-0.8346) for RSV. Conclusion: The IIF presents good sensitivity, but moderate specificity for RSV. However, IIF fails to detect other respiratory viruses. The introduction of PCR would improve the etiological diagnosis of ARI of viral origin.

Vimentin and Anti Vimentin Antibodies in Chagas' Disease / Vimentina e Anticorpos Anti-Vimentina na Doença de Chagas

Abstract Background: Vimentin is a main structural protein of the cell, a component of intermediate cell filaments and immersed in cytoplasm. Vimentin is mimicked by some bacterial proteins and anti-vimentin antibodies occur in autoimmune cardiac disease, as rheumatic fever. In this work we studied vimentin distribution on LLC-MK2 cells infected with T. cruzi and anti-vimentin antibodies in sera from several clinical pictures of Chagas' disease or American Trypanosomiasis, in order to elucidate any vimentin involvement in the humoral response of this pathology. Objective: We standardized an indirect immunofluorescence assay (IFI) to determine sub cellular expression in either parasites and host cells, and ELISA to evaluate anti-vimentin antibodies in sera fron chagasic patients. Methods: We analyzed the distribution of vimentin in culture cells using indirect fluorescent assays, using as external controls anti-T. cruzi sera, derived from chronic infected patients for identification of the parasites in the same model. After infection and growth of T.cruzi amastigotes, those cells express larger amounts of vimentin, with heavy staining of cytoplasm outside the parasitophorous vacuole and some particle shadowing patterns, suggesting that vimentin are associated with cell cytoplasm. Anti-vimentin antibodies were present in most American trypanosomiasis samples, but notably, they are much more present in acute (76, 9%) or clinical defined syndromes, especially cardiac disease (87, 9%). Paradoxically, they were relatively infrequent in asymptomatic (25%) infected patients, which had a clearly positive serological reaction to parasite antigens, but had low frequency of anti-vimentin antibodies, similar to controls (2,5%). Conclusion: Our current data revealed that anti-vimentin antibodies induced during T. cruzi infection could be a marker of active disease in the host and its levels could also justify drug therapy in American Trypanosomiasis chronic infection, as a large group of asymptomatic patients would be submitted to treatment with frequent adverse reactions of the available drugs. Anti-vimentin antibodies could be a marker of cardiac muscle cell damage, appearing in American Trypanosomiasis patients during active muscle cell damage.

Resumo Fundamento: A Vimentina é uma proteína estrutural importante da célula, um componente dos filamentos celulares intermediários e imersa no citoplasma. Algumas proteínas bacterianas imitam a Vimentina e anticorpos anti-vimentina ocorrem em doenças cardíacas auto-imunes, como a febre reumática. Neste trabalho, estudamos a distribuição de vimentina em células LLC-MK2 infectadas com T. Cruzi e anticorpos anti-vimentina em soros de várias imagens clínicas da doença de Chagas ou tripanossomíases americanas, a fim de elucidar qualquer implicação da vimentina na resposta humoral desta patologia. Objetivo: padronizamos um teste de imunofluorescência indireta (IFI) para determinar a expressão subcelular em parasitas e células hospedeiras, e ELISA para testar anticorpos anti-vimentina em soros de pacientes chagásicos. Métodos: analisamos a distribuição de vimentina em células de cultura usando ensaios fluorescentes indiretos, utilizando como controles externos soros anti-T. Cruzi, derivados de pacientes com infecção crônica para a identificação de parasitas no mesmo modelo. Após a infecção e o crescimento de amastigotas de T. Cruzi, essas células expressam grandes quantidades de vimentina, com forte coloração do citoplasma fora da vacuola parasitófora e alguns padrões de sombreamento das partículas, sugerindo que a vimentina está associada ao citoplasma da célula. Os anticorpos anti-vimentina estavam presentes na maioria das amostras americanas de tripanossomíases, mas estão notavelmente mais presentes em síndromes agudas ou clinicamente definidas (76,9%), especialmente em doenças cardíacas (87,9%). Paradoxalmente, eram relativamente infrequentes em pacientes infectados assintomáticos (25%), que apresentavam uma reação sorológica claramente positiva aos antígenos parasitas, mas apresentavam baixa frequência de anticorpos anti-vimentina, semelhante aos controles (2,5%). Conclusão: Nossos dados atuais revelaram que os anticorpos anti-vimentina induzidos durante a infecção por T. Cruzi poderiam ser um marcador de doença ativa no hospedeiro e seus níveis também poderiam justificar o tratamento farmacológico em infecção crônica com tripanossomíase americana, uma vez que um grande grupo de pacientes assintomáticos seria submetido a tratamento com reações adversas frequentes aos medicamentos disponíveis. Os anticorpos anti-vimentina poderiam ser um marcador de danos nas células do músculo cardíaco, que aparece em pacientes com tripanossomíase americana durante o dano das células musculares ativas.

Papel del factor neurotrófico de origen cerebral y de la neurotropina-3 en la relación de Chlamydophila pneumoniae con la esquizofrenia / The relationship of Chlamydophila pneumoniae with schizophrenia: The role of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) in this relationship

Several pathogens have been suspected of playing a role in the pathogenesis of schizophrenia. Chronic inflammation has been proposed to occur as a result of persistent infection caused by Chlamydophila pneumoniae cells that reside in brain endothelial cells for many years. It was recently hypothesized that brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) may play prominent roles in the development of schizophrenia. NT-3 and BDNF levels have been suggested to change in response to various manifestations of infection. Therefore, we aimed to elucidate the roles of BDNF and NT3 in the schizophrenia-C. pneumoniae infection relationship. RT-PCR, immunofluorescence and ELISA methods were used. Fifty patients suffering from schizophrenia and 35 healthy individuals were included as the patient group (PG) and the healthy control group (HCG), respectively. We detected persistent infection in 14 of the 50 individuals in the PG and in 1 of the 35 individuals in the HCG. A significant difference was found between the two groups (p < 0.05). Twenty-two individuals in the PG and 13 in the HCG showed seropositivity for past C. pneumoniae infection, and no difference was observed between the groups (p > 0.05). C. pneumoniae DNA was not detected in any group. A significant difference in NT-3 levels was observed between the groups, with very low levels in the PG (p < 0.001). A significant difference in BDNF levels was also found, with lower levels in the PG (p < 0.05). The mean serum NT-3 level was higher in the PG cases with C. pneumoniae seropositivity than in seronegative cases; however, this difference was not statistically significant (p > 0.05). In conclusion, we suggest that NT-3 levels during persistent C. pneumoniae infection may play a role in this relationship.

Existe la sospecha de que algunos patógenos pueden desempeñar un papel en la patogénesis de la esquizofrenia; en ese contexto, se ha propuesto que la infección persistente causada por células de Chlamydophila pneumoniae presentes en las células endoteliales cerebrales durante muchos años lleva a la inflamación crónica. Recientemente se ha planteado la hipótesis de que el factor neurotrófico de origen cerebral (BDNF, por sus siglas en inglés) y la neurotropina-3 (NT-3) podrían estar implicados en el desarrollo de la esquizofrenia, y se ha sugerido que sus niveles se modifican en respuesta a diversas manifestaciones de la infección. En esta investigación intentamos esclarecer el papel que desempeñan el BDNF y la NT3 en la relación entre la esquizofrenia y la infección por C. pneumoniae. Se utilizaron métodos de RT-PCR, inmunofluorescencia y ELISA. Se incluyeron 50 pacientes con esquizofrenia y 35 individuos sanos como grupo de pacientes (GP) y grupo de controles sanos (GCS), respectivamente. Detectamos una infección persistente en 14 sujetos del GP y en 1 de los del GCS, lo que constituyó una diferencia significativa (p < 0,05). Veinte participantes del GP y 13 del GCS fueron seropositivos para una infección pasada por C. pneumoniae, diferencia no significativa (p > 0,05). No se detectó ADN de C. pneumoniae en ninguno de los dos grupos. Se observó una diferencia significativa entre los grupos en los niveles de NT-3, que fueron muy bajos en el GP (p < 0,001), y de BDNF, inferiores en el GP (p < 0,05). La concentración sérica media de NT-3 fue mayor en los individuos seropositivos para C. pneumoniae en comparación con los seronegativos, pero esta diferencia no alcanzó significación estadística (p > 0,05). Sugerimos que los niveles de NT-3 durante una infección persistente por C. pneumoniae pueden estar implicados en la relación de Chlamydophila pneumoniae con la esquizofrenia.

Monitoramento de vírus respiratórios na região metropolitana de Belo Horizonte, 2011 a 2013 / Monitoreo de vírus respiratórios en la región metropolitana de Belo Horizonte, 2011-2013 / Monitoring respiratory virus infection in the metropolitan area of Belo Horizonte, Brazil, 2011-2013

OBJETIVO: analisar a circulação dos vírus respiratórios em residentes na região metropolitana de Belo Horizonte, Brasil, hospitalizados em Belo Horizonte, de 2011 a 2013. MÉTODOS: estudo descritivo de 5.158 indivíduos com síndrome respiratória aguda grave; foram comparadas as características dos casos confirmados com casos descartados ou sem coleta de swab. RESULTADOS: metade dos vírus isolados foi da influenza A, especialmente os subtipos A(H1N1)pdm09 em pessoas de 20-59 anos e A(H3N2) naquelas com 60 anos ou mais; crianças menores de cinco anos tiveram identificado, com maior frequência, o vírus sincicial respiratório (65,6%), seguido pelo vírus da influenza A (21,2%); o vírus da influenza circulou em todas as estações do ano, e seus períodos de maior incidência intercalaram-se com os de maior atividade do vírus sincicial respiratório. CONCLUSÃO: o monitoramento dos vírus respiratórios contribui para o conhecimento dos períodos de circulação viral e a adoção de medidas de controle específicas.

OBJETIVOS: analizar la circulación de virus respiratorios en residentes de la región metropolitana de Belo Horizonte, Brasil, hospitalizados entre 2011 y 2013. MÉTODOS: estudio descriptivo de 5.158 individuos con infección respiratoria aguda grave; fueron comparadas las características de los casos confirmados con los descartados o sin colecta de swab. RESULTADOS: la mitad de los virus aislados fueron influenza A, especialmente subtipos A(H1N1)pdm09 en personas entre 20-59 años, y A(H3N2) en personas de 60 años o más; los niños menores de cinco años presentaron, con mayor frecuencia, el virus sincicial respiratorio (65,6%), seguido por influenza tipo A (21,2%); el virus de la Influenza circuló en todas las estaciones y los periodos de mayor incidencia se intercalaron con los de mayor actividad del virus sincicial. CONCLUSIÓN: el monitoriamente del virus respiratorio contribuyo para el conocimiento de los periodos de circulación viral y la adopción de medidas de control específicas.

OBJECTIVE: to analyze the circulation of respiratory viruses in people living in the metropolitan area of Belo Horizonte, Brazil, and hospitalized in Belo Horizonte from 2011 to 2013. METHODS: this is a descriptive study of 5,158 patients with Severe Acute Respiratory Syndrome; a comparison was made between the characteristics of confirmed cases and those of discarded cases or cases without swab samples. RESULTS: Influenza A virus accounted for half the isolated viruses, especially subtype A(H1N1)pdm09 among patients aged 20-59 years old, and subtype A(H3N2) in those aged 60 or over; the most frequently identified respiratory virus among children under five years old was respiratory syncytial virus (65.6%), followed by influenza A virus (21.2%); influenza virus circulated in all seasons of the year and its periods of greatest incidence were interspersed with those of higher Respiratory Syncytial Virus activity. CONCLUSION: monitoring respiratory viruses contributes to knowledge about periods of virus circulation and the adoption of specific control measures.

Sensitivity and specificity of parallel or serial serological testing for detection of canine Leishmania infection

In Brazil, human and canine visceral leishmaniasis (CVL) caused byLeishmania infantum has undergone urbanisation since 1980, constituting a public health problem, and serological tests are tools of choice for identifying infected dogs. Until recently, the Brazilian zoonoses control program recommended enzyme-linked immunosorbent assays (ELISA) and indirect immunofluorescence assays (IFA) as the screening and confirmatory methods, respectively, for the detection of canine infection. The purpose of this study was to estimate the accuracy of ELISA and IFA in parallel or serial combinations. The reference standard comprised the results of direct visualisation of parasites in histological sections, immunohistochemical test, or isolation of the parasite in culture. Samples from 98 cases and 1,327 noncases were included. Individually, both tests presented sensitivity of 91.8% and 90.8%, and specificity of 83.4 and 53.4%, for the ELISA and IFA, respectively. When tests were used in parallel combination, sensitivity attained 99.2%, while specificity dropped to 44.8%. When used in serial combination (ELISA followed by IFA), decreased sensitivity (83.3%) and increased specificity (92.5%) were observed. Serial testing approach improved specificity with moderate loss in sensitivity. This strategy could partially fulfill the needs of public health and dog owners for a more accurate diagnosis of CVL.

Evaluación y comparación de pruebas serológicas para la detección de la neosporosis bovina en Argentina / Evaluation and comparison of serological methods for the detection of bovine neosporosis in Argentina

Neospora caninum is a protozoan parasite that causes abortion and important economic losses in cattle worldwide. The accurate diagnosis of neosporosis is essential for management and control measures. The aims of this study were: i) to evaluate the performance of an in-house enzyme-linked immunosorbent assay based on the 38 kDa native antigen (p38-ELISA) to diagnose bovine neosporosis in Argentina using a well- characterized local sera panel from experimentally infected and naturally exposed cattle and ii) to compare the diagnostic performance and agreement of three N. caninum serological tests: p38-ELISA, indirect fluorescence antibody test (IFAT) and immunoblotting (IB) using the same sera panel. Serum samples testing either positive or negative by IFAT and IB were considered "Relative Standards of Comparison" (RSC) and used for p38-ELISA evaluation. Receiver operating characteristics analysis revealed that p38-ELISA was highly accurate (area under the curve= 0.982) according to RSC with a cut-off index of 0.0905. Relative sensitivity and specificity of p38-ELISA were 97.8 % and 99.5 %, respectively and agreement between RSC and p38-ELISA was almost perfect (k= 0.97). The evaluation and performance comparison of serological tests were performed according to the definition of gold standard based on the decision of the "majority of tests". All tests displayed high sensitivity and specificity values (greater than 95 %); and excellent agreement. This study describes the accurate performance of p38-ELISA evaluated locally and the highly accurate diagnostic performance of the studied tests for the detection of anti-N. caninum antibodies in cattle from Argentina.

Neospora caninum es un parásito protozoo responsable de abortos y pérdidas económicas en bovinos. La realización de un diagnóstico serológico preciso y con resultados comparables obtenidos por diferentes pruebas contribuye al manejo de este problema y a encarar medidas de control. Los objetivos del presente trabajo fueron los siguientes: 1) evaluar en Argentina una prueba de enzimoinmunoensayo in-house con el antígeno nativo de 38 kDa de N. caninum (ELISA-p38) para el diagnóstico de la neosporosis bovina, utilizando un panel de sueros locales bien caracterizados, procedentes de bovinos infectados de modo experimental o naturalmente expuestos; 2) comparar el desempeño y establecer el nivel de concordancia de tres pruebas serológicas para la detección de N. caninum, ELISA-p38, inmunofluorescencia indirecta (IFI) e inmunoblot (IB), con el mismo panel de sueros. Los sueros que resultaron positivos o negativos a IFI e IB fueron considerados como estándares relativos de comparación (ERC) para evaluar la prueba de ELISA-p38. El análisis de característica operativa del receptor determinó que la prueba de ELISA-p38 fue altamente precisa (área bajo la curva= 0,982) usando el punto de corte 0,0905. La sensibilidad y especificidad relativa del ELISA-p38 fue 97,8 % y 99,5 %, respectivamente, con una concordancia casi perfecta (k= 0,97) respecto del ERC. La comparación del desempeño de las pruebas se realizó usando como gold standard el criterio de la decisión de la "mayoría de las pruebas". Las pruebas exhibieron altos valores de sensibilidad y especificidad (mayores del 95 %) y excelente concordancia. Este trabajo describe un buen desempeño de la prueba de ELISA-p38 evaluada localmente y adecuada performance diagnóstica de las pruebas serológicas analizadas para la detección de anticuerpos anti N. caninum en bovinos de Argentina.

Seroepidemiological analysis of toxoplasmosis in college students

Background: Toxoplasmosis is a zoonosis caused by an obligate intracellular parasite, Toxoplasma gondii, which affects warm-blooded animals including humans. Its prevalence rates usually vary in different regions of the planet. Methods: In this study, an analysis of the seroprevalence of toxoplasmosis among Brazilian students was proposed by means of IgG specific antibodies detection. The presence of anti-Toxoplasma gondiiantibodies by indirect fluorescent antibody test (IFAT) was also evaluated in order to compare it with enzyme-linked immunosorbent assay (ELISA) and to assess the use of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and o-phenylenediamine dihydrochloride chromogens. Results: The IFAT method showed a seroprevalence of 22.3%. These results were similar to those obtained by ELISA (24.1%). The seroprevalence was directly estimated from the IgG avidity, which showed that in a sample of 112 students, three of them had acute infection, an incidence of 1.6% in the studied population. Conclusion: In this study, the use of different chromogenic substrates in immunoenzymatic ELISA assays did not display different sensitivity in the detection of T. gondii-reagent serum. The extrapolation of results to this population must be carefully considered, since the investigation was conducted on a reduced sample. However, it allows us to emphasize the importance of careful and well prepared studies to identify risk factors for toxoplasmosis, to adopt preventive measures and to offer guidance to at-risk populations about the disease.

Comparación de dos métodos serológicos para el diagnóstico de anticuerpos IgG anti-Toxoplasma gondii en neonatos / Comparison of two serological methods for the diagnosis IgG antibody against Toxoplasma gondii in newborn

Disímiles son los métodos serológicos empleados para la determinación de anticuerpos IgG anti-Toxoplasma gondii en diferentes muestras de estudio. El objetivo es realizar una comparación entre el método de Inmunofluorescencia Indirecta y el Toxoplasma látex porBrunella para demostrar cual es el método más sensible y específico para determinar seroprevalencia de anticuerpos IgG anti- Toxoplasma gondii en neonatos asistidos en la Sala de Neonatología del Hospital Valdimir Ilich Lenin. Se analizaron 30 muestras de sueros de niños recién nacidos asistidos en este Servicio por las dos pruebas, de ellas se conformaron dos grupos de trabajo. Los resultados demostraron que la prueba de Inmunofluorescencia Indirecta es la más útil para este diagnóstico, coincidiendo con investigaciones similares realizadas

Dissimilar are the methods used to determine the seroprevalence of IgG antibodies against to Toxoplasma gondii in different samples. In this research were compared to Indirect Immunofluorescence and Toxoplasma Latex by Brunelli to prove which of them is the most sensitive and specific to determine seroprevalence of IgG anti-Toxoplasma gondii in newborn in Neonatology Service at Lenin Hospital of Holguin Province, Cuba is the main objective. Thirty samples were analyzed of newborns treated in Neonatology Service using these methods, besides two working groups were formed. The sensitivity and specificity of Indirect Immunofluorescence were 100 % and 95 % respectively and Toxoplasma latex reported a sensitivity of 96.1 % and a specificity of 89.6 %. These results showed that the Indirect Immunofluorescence Technique is the most useful for these diagnostic and this result are similar with others investigations

Determinación de anticuerpos IgG contra toxoplasma gondii en neonatos de la sala de neonatología del Hospital General Universitario "Vladimir Ilich Lenin", Holguín / Determination of anti-toxoplasma gondii IgG antibodies among neonates from the neonatology ward at Vladimir Ilich Lenin General University Hospital in Holguín

INTRODUCCIÓN: la infección por Toxoplasma gondii en niños puede ser congénita o adquirida. La infección del feto se produce cuando la madre tiene el primer contacto con el parásito durante la gestación, por lo que debe considerarse como una fuente potencial de infección al feto durante este período. OBJETIVOS: demostrar la presencia de anticuerpos IgG anti-Toxoplasma gondii en neonatos. MÉTODOS: se analizaron 30 muestras de sueros de niños recién nacidos asistidos en el Servicio de Neonatología del Hospital General Universitario "Vladimir Ilich Lenin". El comportamiento serológico de esta infección se determinó por la presencia de anticuerpos IgGh anti- Toxoplasma gondii a través de la técnica de inmunofluorescencia indirecta. Resultados: 23,3 % de las muestras resultaron positivas, corroborando la circulación del parásito y su contacto con este grupo de riesgo. CONCLUSIONES: se sugiere la necesidad del cumplimiento del programa establecido en Cuba para esta zoonosis en este grupo poblacional.

INTRODUCTION: Toxoplasma gondii infection in children may be either congenital or acquired. Fetal infection occurs when the mother has her first contact with the parasite during pregnancy. Therefore, this event should be viewed as a potential source of infection for the fetus during this period. OBJECTIVES: determine the presence of anti-Toxoplasma gondii IgG antibodies in neonates. METHODS: Thirty serum samples were analyzed from newborns cared for at the Neonatology Service of Vladimir Ilich Lenin General University Hospital. Serologic behavior of the infection was determined by the presence of anti-Toxoplasma gondii IgGh antibodies, using the indirect immunofluorescence technique. RESULTS: 23.3% of the samples were positive, confirming the circulation of the parasite and its contact with this risk group. CONCLUSIONS: it is suggested that the Cuban program for this zoonosis in the population group under study be complied with.

Diagnóstico de neumocistosis a través de la inmunofluorescencia directa y la PCR anidada en pacientes con enfermedad pulmonar obstructiva crónica / Diagnosis through pneumocystosis direct immunofluorescence and nested PCR in patients with chronic obstructive pulmonary disease

La asociación EPOC- neumocitosis está descrita y existe la necesidad de optimizar la diferenciación entre enfermedad y colonización. Demostrar la presencia del Pneumocistys Jirovecci, como patógeno y/o colonizador. Estudio descriptivo, analítico, de cohorte de pacientes con diagnóstico de EPOC del Hospital General del Oeste (Caracas, Venezuela) durante el periodo de abril – julio 2012 con seguimiento hasta julio de 2013 y aplicación de la técnica de inmunofluorescencia directa (IFD) y/o PCR anidada (PCRa) en muestra de esputo (espontáneo – inducido) durante los periodos asintomáticos o durante la exacerbación del EPOC en seguimiento de un año. Se incluyeron 20 pacientes en el reclutamiento, con seguimiento al primer control de 5 pacientes; de estos solo 2 cumplieron la medición de esputo. Para la tercera evaluación una paciente había fallecido y la otra no cumplió con el seguimiento. Se demostró IFI+ en 10% de los reclutados, todos con clínica de exacerbación de la EPOC. La PCRa se demostró en 45%, 2 con exacerbación y el resto sin exacerbación. De los dos pacientes de seguimiento, una fue positiva para PCRa y no tenía exacerbación, la otra negativa por ambos métodos. Se demostró infección por Pj en los pacientes con EPOC exacerbado a través de IFI y la PCRa señala su positividad en infección pero también en aquellos sin infección o exacerbación documentando así la colonización y potencial fuente de infección para neumocistosis. Se demostró infección por Pj en paciente con exacerbación y colonización a través de la evidencia del genoma del hongo en pacientes sin exacerbación.

Pneumocistosis and COPD association is described and there is a need to differenciate between disease and colonization. To document the presence of Pnemocistys jirovecci as pathogenic or colonizer by direct immunofluoresencence technique (DIF) and/or nested polymerase chain reaction (nPCR) in sputum (spontaneous-induced) during asymptomatic periods or exacerbation of COPD during a year of follow-up. This is a a descriptive, analytic cohort of patients with COPD of the Hospital General del Oeste (Caracas, Venezuela) . They were studied during April - July 2012, with follow-up until July 2013. 20 patients were included. The first control follow up was in 5 patients with only two measures of IFI - PCRa. For the third evaluation one patient had died and the other did not comply with control. IFI + was demonstrated in 10 % of the recruits, all had COPD, exacerbation. PCRa + was demonstrated in 45%, 2 with exacerbation and all other without exacerbation. From the two followed patients one was positive for PCRn and had no exacerbation, the other was negative by both methods. Pj infection was demonstrated in patients with exacerbated COPD by IFI+ and the PCRa positivity in infection but also in those without infection or exacerbation documenting the colonization and potential source of infection for Pj. Pj infection wasdiagnosed in patients with exacerbation COPD and colonization through the evidence of the genome of the fungus in patients without exacerbation.

Serological survey on Ehrlichia sp. among dogs in the central region of Rio Grande do Sul / Pesquisa sorológica de Ehrlichia sp. em cães da região central do Rio Grande do Sul

A serological survey on Ehrlichia canis was conducted among dogs in the central area of the state of Rio Grande do Sul, where the tick Rhipicephalus sanguineus is a common parasite of dogs. Out of a total of 316 dogs attended at the veterinary teaching hospital in the municipality of Santa Maria, only 14 (4.43%) reacted positively to E. canis antigens in the indirect immunofluorescence assay, with the following endpoint titers: 80 (three dogs), 160 (five), 320 (four), 640 (one) and 1280 (one). Like in previous studies in other regions of the state of Rio Grande do Sul, only a very small portion of the dogs in Santa Maria presented antibodies reactive to E. canis, even though canine infestations due to R. sanguineus are very common in this study region. These results contrast with other regions of Brazil, where E. canis is endemic among canine populations, with seropositivity values generally higher than 30%. Genetic differences among the R. sanguineus populations in South America might be implicated in these contrasting results.(AU)

Foi realizada uma pesquisa sorológica para Ehrlichia canis, em cães, na região central do estado do Rio Grande do Sul, onde o carrapato Rhipicephalus sanguineus é um parasita comum em cães. De um total de 316 cães atendidos no Hospital Veterinário Universitário no Município de Santa Maria, somente 14 (4,43%) reagiram positivamente para o antígeno de E. canis pela reação de imunofluorescência indireta, com os seguintes títulos finais: 80 (3 cães), 160 (5), 320 (4), 640 (1) e 1.280 (1). Semelhante aos estudos anteriores em outras regiões do estado do Rio Grande do Sul, apenas uma pequena parcela dos cães de Santa Maria apresentaram anticorpos reativos para E. canis, mesmo que as infestações caninas por R. sanguineus sejam muito comuns na região de estudo. Esses resultados contrastam com outras regiões do Brasil, nas quais E. canis é endêmica entre a população canina, com valores de soropositividade geralmente superiores a 30%. Diferenças genéticas entre as populações de R. sanguineus, na América do Sul, poderiam estar envolvidas nesses resultados contrastantes.(AU)

Primer Consenso Argentino para la Estandarización de la Determinación de Anticuerpos Anti-Nucleares por Inmunof uorescencia Indirecta-HEp-2 / First Argentine Consensus for Standardization of Antinuclear Antibodies by Indirect Immunofluorescence-HEp-2 / Primeiro Consenso Argentino para a Padronizagáo da Determinagáo de Anticorpos Antinucleares por Imunofluorescéncia Indireta-HEp-2

La presencia de anticuerpos antinucleares (AAN) es el denominador común de muchas enfermedades autoinmunes sistémicas y su significancia clínica depende de la metodología utilizada en su determinación. En la actualidad, la inmunofluorescencia indirecta (IFI) utilizando células HEp-2 como sustrato es la técnica más usada. Siendo un procedimiento subjetivo se deben optimizar los métodos de estandarización de las distintas variables involucradas, para asegurar la calidad de los resultados obtenidos. El uso de este sustrato permite la descripción no sólo de patrones de fluorescencia nucleares sino también citoplasmáticos y de diferentes organelas. El 29 de agosto de 2008 se llevó a cabo en Buenos Aires el Primer Consenso Argentino para la Estandarización de la Determinación de AAN por IFI-HEp-2, con la participación de 28 expertos. Se discutieron los aspectos metodológicos más importantes y se decidió llamar a la determinación "anticuerpos anti núcleo-citoplasmáticos". Se consensuó la sigla representativa de la determinación, el nombre en español de los diferentes patrones y el uso de controles de calidad internos y externos. La unificación de criterios llevará a la optimización de los resultados y a su correcta interpretación.

Antinuclear antibodies (ANA) are a common feature of many systemic autoimmune diseases. Their clinical significance depends on working conditions. Nowadays, indirect immunofluorescence (IFI), using HEp-2 cells as substrate, is the most used assay. Since IFI is a subjective method, different variables should be strictly standardized to assure the quality of the results. By using HEp-2 cells, not only a nuclear fluorescent pattern will be described but also cytoplasmic and different organelle patterns. In order to standardize the operative procedures, the 1st Argentine Consensus for AAN IFI HEp-2 determination took place in Buenos Aires on August 29, 2008, with 28 experts as participants. The most important methodological aspects were discussed and the assay was decided to be named: anti nuclear- cytoplasmic antibodies. Consesus was also CAICYThed about the acronym for the determination, the Spanish names for the different patterns and the use of internal and external quality controls. Using common criteria will improve the quality of the results and optimize assay interpretation.

A presenga de anticorpos antinucleares (AAN) é o denominador comum de muitas doengas autoimunes sistémicas e sua significancia clínica depende da metodologia utilizada em sua determinagáo. Na atualidade, a imunofluorescéncia indireta (IFI) utilizando células HEp-2 como substrato é a técnica mais utilizada. Sendo um procedimento subjetivo devem ser otimizados os métodos de padronizagáo das diferentes variáveis envolvidas, para garantir a qualidade dos resultados obtidos. O uso deste substrato permite a descrigáo náo apenas de padróes de fluorescéncia nucleares mas também citoplasmáticos e de diferentes organelas. Em 29 de agosto de 2008, foi levado a cabo, em Buenos Aires, o Primeiro Consenso Argentino para a Padronizagáo da Determinagáo de AAN por IFI-HEp-2, com a participagáo de 28 especialistas. Foram discutidos os aspectos metodológicos mais importantes e se decidiu chamar a determinagáo de "anticorpos antinúcleo-citoplasmáticos". Foi estabelecida por consenso a sigla representativa da determinagáo, o nome em espanhol dos diferentes padróes e o uso de controles de qualidade internos e externos. A unificagáo de critérios levará a otimizago dos resultados e a sua correta interpretagáo.

An indirect immunofluorescence antibody test employing whole eggs as the antigen for the diagnosis of abdominal angiostrongyliasis

Abdominal angiostrongyliasis is a potentially fatal zoonotic disease with a broad geographical distribution throughout Central and South America. This study assessed the performance of Angiostrongylus costaricensis eggs as the antigen in an indirect immunofluorescence assay for the determination of parasite-specific IgG and IgG1 antibodies. For prevalence studies, an IgG antibody titre > 16 was identified as the diagnostic threshold with the best performance, providing 93.7 percent sensitivity and 84.6 percent specificity. Cross reactivity was evaluated with 65 additional samples from patients with other known parasitic infections. Cross reactivity was observed only in samples from individuals infected with Strongyloides stercoralis. For clinical diagnosis, we recommend the determination of IgG only as a screening test. IgG1 determination may be used to increase the specificity of the results for patients with a positive screening test.

A decade long experience of anti-neutrophil cytoplasmic antibody testing in a tertiary care referral center in North India: Perspective from a developing country.

Background: In a developing, tropical country like India, discontinuous power supply, high temperatures during summer, and lack of consistent cold chain and funds provide a challenging atmosphere for anti-neutrophil cytoplasmic antibody (ANCA) testing and reporting. However, a simple in-house test and testing algorithm are described here, which have been developed and tested over time. Materials and Methods: An analysis of a decade of testing and reporting of ANCA in the Department of Immunopathology in a tertiary referral health care center was performed to highlight the importance of testing for ANCA in proposed 1999 guideline recommended indications. Results: A total of 4195 ANCA tests were conducted from 2000 to 2009. Overall, 2060 (49%) requests had indications which met the 1999 guidelines, while the remaining 2135 (51%) fell outside the guidelines. A total of 350 samples (8.3%) were positive for ANCA on indirect immunofluorescence (IIF), out of which 212 were guideline recommended and 138 (3.2%) were non-guideline recommended ANCA requests; thus, 3.2% of non-small vessel ANCA associated vasculitis (non-SVAAV) conditions showed false positive results when the population was otherwise unselected. Maximum requests (1432) were for rapidly progressive renal failure/acute renal failure. Conclusions: The audit shows that compliance with guidelines for ANCA testing would decrease the number of false positive results. In-house screening for ANCA by IIF is cost-effective and must be performed at least twice on two different samples from the same patient or on two different sets of ANCA preparations in all the cases who requested ANCA testing with a proposed 1999 guideline recommended indication.