IgG Avidity in Samples Collected on Filter Paper: Importance of The Early Diagnosis of Congenital Toxoplasmosis / Avidez de IgG em amostras coletadas em papel filtro: Importância no diagnóstico precoce da toxoplasmose congênita

Abstract Objective The purpose of the present study is to standardize and evaluate the use of the immunoglobulin G (IgG) antibody avidity test on blood samples from newborns collected on filter paper to perform the heel test aiming at its implementation in ongoing programs. Methods Blood samples from newborns were collected on filter paper simultaneously with the heel prick test. All samples were subjected to immunoglobulin M IgM and IgG enzyme-linked immunosorbent assays (ELISA). Peripheral blood was collected again in the traditional way and on filter paper from newborns with high IgG levels (33). Three types of techniques were performed, the standard for measuring IgG in serum, adapted for filter paper and the technique of IgG avidity in serum and on filter paper. The results of the avidity test were classified according to the Rahbari protocol. Results Among the 177 samples, 17 were collected in duplicate from the same child, 1 of peripheral blood and 1 on filter paper. In this analysis, 1 (5.88%) of the 17 samples collected in duplicate also exhibited low IgG avidity, suggesting congenital infection. In addition, the results obtained from serum and filter paper were in agreement, that is, 16 (94.12%) samples presented high avidity, with 100% agreement between the results obtained from serum and from filter paper. Conclusion The results of the present study indicate that the avidity test may be another valuable method for the diagnosis of congenital toxoplasmosis in newborns.

Resumo Objetivo O objetivo do presente estudo é padronizar e avaliar a utilização do teste de avidez de anticorpos imunoglobulina G (IgG) em amostras de sangue de recémnascidos (RNs) coletadas em papel filtro para a realização do teste do pezinho visando a implementação nos programas já vigentes. Métodos Foram coletadas amostras de sangue de recém-nascidos em papel filtro simultaneamente ao teste do pezinho. Em todas as amostras, foram realizados os testes imunoenzimáticos (ELISA) imunoglobulina M (IgM) e IgG. Dos RNs que apresentaram altos índices de IgG (33), foi novamente coletado sangue periférico da forma tradicional e em papel filtro. Foram realizadas técnicas padrão para a dosagem de IgG em soro, adaptadas para papel filtro, e a técnica de avidez de IgG em soro e em papel filtro. Os valores obtidos para o teste de avidez foram classificados de acordo com o protocolo de Rahbari. Resultados Dentre as 177 recoletas, em 17 amostras foi realizada a coleta simultânea de sangue periférico e papel filtro da mesma criança. Nesta análise, 1 (5,88%) das 17 amostras coletadas em duplicata obteve também baixa avidez de IgG, sugerindo infecção congênita da criança, e houve concordância entre os resultados obtidos em soro e em papel filtro: 16 (94,12%) das amostras apresentaram alta avidez, com concordância de 100% entre os resultados obtidos em soro e em papel filtro. Conclusão Os dados do presente trabalho evidenciam que o teste de avidez poderá ser mais um método valioso a ser utilizado no diagnóstico da toxoplasmose congênita em RNs.

Occurrence of parasites in salads in restaurants in Aparecida de Goiânia, Goiás, Brazil

Parasitoses are the most widespread diseases in the world. They are transmited via contaminated water or food. Considering that the daily consumption of vegetables is estimated at 142g per person, the purpose of this study was to evaluate the occurrence of parasites in salads available for consumption in restaurants in Aparecida de Goiânia, Goiás State. Salad samples were collected from the restaurants and parasitological analysis was performed using the Willis, Hoffman, Faust and Ziehl Neelsen techniques as well as cultures for the isolation of free-living amoebae. 51 samples were analyzed, 16 (31.4%) were positive. The parasites detected were: Acanthamoeba spp. in 12 (23.5%); free-living larvae, Schistosoma mansoni and Entamoeba coli in 1 (2.0%); Endolimax nana in 2 (3.9%). The PCR technique determined that 17.6% of the samples presented Toxoplasma gondii DNA. These techniques evidenced that the salad samples presented parasite contamination not only in the restaurants with the lowest price per Kg, but also in the most expensive ones. Therefore, in addition to effective sanitary surveillance, prophylactic measures are necessary regarding suppliers, handlers and restaurant owners to prevent the spread of these and other parasites.

Epidemiological factors associated with Toxoplasma gondii infection in postpartum women treated in the public healthcare system of Goiânia, State of Goiás, Brazil

Abstract INTRODUCTION: Knowledge of the epidemiological profile and risk factors for Toxoplasma gondii infection among postpartum women is a relevant issue, because this protozoan can be vertically transmitted to the developing fetus, which can cause severe and debilitating disease. The aim of this study was to assess the risk factors associated with T. gondii infection in postpartum women in Goiânia, GO, Brazil. METHODS: This cross-sectional study comprised 229 postpartum women, among whom 204 were chronically infected (IgG+/IgM-), and 25 were seronegative (IgG-/IgM-; control group). All the patients were asked to complete a form to provide sociodemographic, clinical, dietary, and cultural information. The data were analyzed to compare seropositivity and risk factors based on the odds ratio (OR) thereof. RESULTS: The sociodemographic characteristics associated with the risk for toxoplasmosis were: education ≤ 8 years [OR: 2.521, confidence interval (CI): 1.01-6.301, p=0.049], and age ≥ 30 years (OR: 4.090; CI: 1.180-14.112, p=0.023). Clinical and behavioral characteristics related to eating raw and undercooked meat, were not found to be risk factors associated with a positive test for toxoplasmosis. CONCLUSIONS: Our findings concur with the results of other studies conducted in Brazil and abroad, where variables such as low levels of schooling, and advanced age (≥ 30 years) are major risk factors for pregnant women to become infected with T. gondii.

Evaluation of the accuracy of parasitological techniques for the diagnosis of intestinal parasites in cats / Avaliação da acurácia de técnicas parasitológicos para o diagnóstico de parasitos intestinais em gatos

Abstract The accuracy of the parasitological techniques of Willis, Hoffman-Pons-Janer or Lutz (HPLJ), Sheather and Faust was evaluated in fecal samples from stray cats caught by the Zoonosis Control Center in Goiânia, Goiás, Brazil. These four techniques were applied separately to analyze 154 fecal samples, and their accuracy was analyzed based on an evaluation of their sensitivity, specificity, positive and negative predictive values, and Kappa index, resulting in the selection of the Willis technique as the nominal gold standard. Of the 154 samples, 115 (74.68%) tested positive for intestinal parasites. The analysis of the frequency of positivity indicated that the HPLJ technique detected 86.1% of the positive samples and was the closest to the gold standard. The analysis of the accuracy of the techniques was evaluated using the most prevalent parasites. The Sheather technique showed the highest accuracy in the detection of Ancylostomatidae, while the Sheather and HPLJ techniques showed similar accuracies in the detection of Cystoisospora spp. when compared to the gold standard. Lastly, the Faust technique showed the highest accuracy in the detection of Toxoplasma gondii when compared to the gold standard. This study underscores the importance of combining parasitological techniques in the diagnosis of intestinal parasites in cats.

Resumo A avaliação da acurácia das técnicas parasitológicas de Willis, Hoffman-Pons-Janer ou Lutz (HPJL), Sheather e Faust foram realizadas em amostras fecais de gatos capturados pelo Centro de Controle de Zoonoses em Goiânia, Goiás. Essas quatro técnicas foram utilizadas separadamente para análise de 154 amostras fecais. A análise de acurácia foi empregada, avaliando-se a sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e índice kappa, sendo a técnica de Willis eleita como padrão-ouro. Das amostras analisadas 74,68% (115/154) foram positivas para enteroparasitos. A análise de frequência de positividade demonstrou que a técnica HPJL detectou 86,1% dos positivos, aproximando-se do padrão-ouro. A avaliação da acurácia foi realizada pela análise dos parasitos mais prevalentes, sendo que, para Ancilostomídeos, a técnica de Sheather apresentou melhor acurácia; para Cystoisospora spp., as técnicas de Sheather e HPJL foram semelhantes e para Toxoplasma gondii, a técnica de Faust apresentou melhor acurácia comparada ao padrão ouro. Este estudo demonstra a importância da associação de técnicas parasitológicas para o diagnóstico de enteroparasitos em gatos.