Evaluación de pruebas inmunológicas en el diagnóstico de Giardia duodenalis y Cryptosporidium spp, Honduras / Evaluation of immunologic tests in the diagnosis of Giardia duodenalis and Cryptosporidium spp., Honduras

Antecedentes: No conocemos datos sobre evaluación de pruebas inmunológicas para mejorar el diagnóstico de Giardia duodenalis y Cryptosporidium spp., agentes etiológicos de diarrea de importancia mundial, en Honduras. Objetivos: Comparar dos pruebas inmunológicas para el diagnóstico de Giardia y Cryptosporidium spp. con microscopía de rutina y determinar su aplicabilidad local. Métodos: Estudio descriptivo transversal. En 2013, 134 muestras de heces recibidas en el Servicio de Parasitología del Hospital Escuela (HE) y 67 muestras del Centro de Salud Alonso Suazo (CSAS) se analizaron con una Prueba Rápida Inmunocromatográfica (PDR). En 2019-2020, 60 muestras de heces del HE se analizaron con una prueba inmunoenzimática ELISA. El protocolo de rutina incluyó examen directo en solución salina y solución de Lugol, coloración tricrómica y coloración ácido resistente modificada (ARM) (HE) y examen directo en solución salina y solución de Lugol (CSAS). Resultados: Cada prueba inmunológica mostró mayor positividad que la microscopía: en 134 muestras del HE para Giardia (6.7% vs 4.5%) y Cryptosporidium (3.7% vs 0.7%), similar en 67 muestras del CSAS (14.9% vs 7.5% para Giardia; 0.7% para Cryptosporidium con la prueba inmunológica). De 60 muestras analizadas por ELISA en HE, 31.7% fue positiva por Giardia vs 18.3% en examen directo y 23.3% en coloración tricrómica; 6.7% positiva por Cryptosporidium spp. vs 3.3% por coloración ARM. Discusión: Pruebas inmunológicas aumentaron significativamente el diagnóstico de ambas parasitosis; sin embargo, publicaciones sobre pruebas similares ofrecieron resultados no concluyentes. Por costo elevado podrían reservarse para pacientes pediátricos, pacientes inmunocomprometidos en hospitales, complementando microscopía. Los laboratorios de salud deben fortalecer capacidad diagnóstica...(AU)

Predominance of Giardia duodenalis AII sub-assemblage in young children from Salvador, Bahia, Brazil / Predominio del subconjunto AII de Giardia duodenalis en niños pequeños de Salvador, Bahía, Brasil

Introduction. Giardia duodenalis is an intestinal protozoan with a high prevalence in children of developing countries. Molecular studies revealed a great genetic diversity of G. duodenalis, with assemblages A and B found mainly in humans. Despite its importance, the information on the molecular epidemiology of human giardiasis is still limited in Brazil. Objective. To characterize G. duodenalis molecular isolates in children from Salvador, Bahia, Brazil. Materials and methods. Giardia duodenalis positive fecal samples were obtained from 71 children from two day care centers and 39 users of a clinical analysis laboratory. Samples were analyzed by PCR-RFLP of the glutamate dehydrogenase (gdh) and beta-giardin genes and by the sequencing of beta-giardin. Results. Of the 110 G. duodenalis samples, 80 (72.7%) amplified one or both target genes. Of these, 62 (77.5 %) were identified as assemblage A and 18 (22.5%) as assemblage B. The subassemblage AII was identified in 58.8% (n=47) of isolates followed by the sub-assemblage AI (18.8%, n=15), BIV (11.2%, n=9), and BIII (5.0%, n=4). The AII sub-assemblage was the most frequent in children of both day care centers whereas AI was found only in the group attended at the clinical laboratory. Sub-assemblage AII predominated in children under two years. Conclusions. The higher frequency of AII sub-assemblage suggests that anthroponotic transmission is more common in Salvador, but that zoonotic transmission pathways are also present and a change in susceptibility to different molecular patterns of Giardia may occur during child growth.

Introducción. Giardia duodenalis es un protozoo intestinal de gran prevalencia en los niños de los países en desarrollo. En estudios moleculares se ha evidenciado la gran diversidad genética de G. duodenalis y se han identificado los conjuntos A y B, principalmente en humanos. A pesar de su importancia, el conocimiento de la epidemiología molecular de la giardiasis humana aún es limitado en Brasil. Objetivo. Caracterizar los aislamientos moleculares de G. duodenalis de muestras tomadas a niños de Salvador, Bahía, Brasil. Materiales y métodos. Las muestras fecales positivas para G. duodenalis se obtuvieron de 71 niños de dos guarderías y de 39 usuarios de un laboratorio de análisis clínicos. Las muestras se analizaron mediante PCR-RFLP de los genes gdh y beta-giardin, y secuenciación de beta-giardin. Resultados. De las 110 muestras de G. duodenalis, en 80 (72,7 %) se amplificaron uno o ambos genes. De estos, 62 (77,5 %) se identificaron como pertenecientes al conjunto A y 18 (22,5 %) al B. El subconjunto AII se identificó en el 58,8 % (n=47) de los aislamientos, seguido del AI en el 18,8% (n=15), el BIV en el 11,2% (n=9) y el BIII en el 5,0% (n=4). El subconjunto AII fue el más frecuente en los niños de ambas guarderías, en tanto que el AI solo se encontró en el grupo atendido en el laboratorio clínico. El subconjunto AII predominó en los niños menores de dos años. Conclusiones. La mayor frecuencia del subconjunto AII sugiere que la transmisión antroponótica es más común en Salvador, pero también existen vías de transmisión zoonóticas, y que pueden ocurrir cambios en la sensibilidad frente a diferentes patrones moleculares de Giardia durante el crecimiento infantil.

Epidemiology of Giardia duodenalis assemblages in Brazil: there is still a long way to go

Giardia duodenalis infection is distributed worldwide and can achieve prevalence around 60%, especially in developing countries. This protozoan is divided into eight assemblages, in which A and B have high zoonotic potential, whereas C to H are host-specific. This scenario is changing as molecular studies progress, highlighting that knowledge on host-specificity still has a long way to go. Understanding the players involved in transmission routes enables rational designs of control strategies. Considering the high prevalence of giardiasis, this review aims to gather together the data on available studies on the distribution of G. duodenalis assemblages in Brazil until September 2020.

Cryptosporidium spp. e Giardia spp. em carnívoros silvestres do Estado do Pará Brasil / Cryptosporidium spp. and Giardia spp. in wild carnivorous animalsthe State of Pará – Brazil

O presente estudo investigou a ocorrência de Cryptosporidium spp. e Giardia spp. em diferentes espécimes silvestres da ordem Carnívora de vida livre e de cativeiro procedentes de municípios do Estado do Pará. Coletou-se amostras fecais de 37 animais distintos (quatro de vida livre e 33 de cativeiro). Para pesquisa de Cryptosporidium spp. e Giardia spp. foram utilizados métodos microscópicos (direto e Kinyoun) e imunológico (RIDA®QUICK Cryptosporidium/Giardia/Entamoeba Combi - N1722). Do total de amostras, 24,32% (9/37) foram positivas, correspondendo a 5,4% (2/37) para Cryptosporidium spp. e 18,91% (7/37) para Giardia spp., respectivamente. Nenhum animal apresentou infecção concomitante para os agentes. Cryptosporidium spp. e Giardia spp., são protozoários zoonóticos que representam um emergente problema de saúde pública. Esses parasitos podem apresentar elevada frequência em regiões em que as condições de saneamento básico são precárias, promovendo surtos de diarreia em animais domésticos, silvestres e no homen. Mamíferos silvestres, como os carnívoros, são susceptíveis à contaminação por enteroparasitas presentes tanto no habitat natural como em cativeiro. Portanto, a pesquisa comprova a presença desses protozoários em carnívoros silvestres, tanto mantidos em criatórios como nos de vida livre no Estado do Pará, considerando-se que esses animais podem atuar como fontes de infecção para o homem, para outros animais e para o meio ambiente.

The present survey has had the purpose to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in free and under captivity carnivorous wild animals, from several counties in the State of Pará. Samples of feces from 37 distinct animals (four in their natural habitat and 33 raised in captivity). For the research of Cryptosporidium spp. and Giardia spp. microscopic immunological, direct and Kinyoun methods were used (RIDA®QUICK Cryptosporidium/Giardia/Entamoeba Combi - N1722). The samples gathered from wild animals have resulted in 24,32% of positive infection on the rate of (9/37), being. 5,4% (2/37) positive to Cryptosporidium spp. and 18,91% (7/37) positive to Giardia spp., what shows that no animals had both infections at the same time. Cryptosporidium spp. and Giardia spp., are zoonotic enteroparasites that have been taking place as an emerging problem to public health. These species of protozoa may reach high levels of frequency in regions where the basic sanitation conditions are precarious, promoting outbreaks of diarrhea to men, wild and domestic animals. Wild mammals, as the carnivorous, are susceptible to contamination by enteroparasites, being present at their natural habitat or captivity. So, the research strengthens the real presence of these protozoas in wild carnivorous in both conditions of life, free or under captivity, in the State of Pará, making us consider the possibility that the cited animals may be natural reservoirs for infections, not only to men but to other animals and also to environment.

Cross-sectional epidemiological investigations of Giardia lamblia in children in Pakistan

ABSTRACT BACKGROUND: The prevalence of Giardia lamblia in Pakistani children is currently unknown. The aim here was to evaluate the prevalence and risk factors of Giardia lamblia in children exhibiting diarrhea. DESIGN AND SETTING: Cross-sectional study at different district healthcare hospitals in Pakistan. METHODS: A total of 800 samples were collected from children aged 0-10 years. Information regarding personal data, demographic data and supposed risk factors was collected through a structured questionnaire. Giardia lamblia was detected through direct microscopy and antigens through the enzyme-linked immunosorbent assay (ELISA). RESULTS: The prevalence of Giardia lamblia was 2.75% through direct microscopy and inflated to 9.5% through ELISA. The demographic factors positively associated with occurrences of giardiasis were age (P = 0.035; odds ratio, OR = 1.96; 95% confidence interval, CI = 1.094-3.533), mother's educational level (P = 0.031; OR = 2.67; 95% CI = 1.186-6.045) and father's educational level (P = 0.004; OR = 3.56; 95% CI = 1.612-7.899). Similarly, among the supposed risk factors, rural residency (P = 0.032; OR = 1.76; 95% CI = 1.098- 2.851), absence of proper sewerage system (P = 0.000; OR = 6.60; 95% CI = 4.029-10.841) and unavailability of safe drinking water (P = 0.000; OR = 4.08; 95% CI = 2.207-7.547) were the factors strongly connected with giardiasis. Abdominal discomfort was a prominent clinical sign with 46% frequency. CONCLUSION: Various risk factors were associated with occurrences of Giardia, thus emphasizing the importance of parents' education, safe drinking water and proper sewerage systems for Pakistani children's health.

Molecular Detection of Giardia intestinalis from Stray Dogs in Animal Shelters of Gyeongsangbuk-do (Province) and Daejeon, Korea

Giardia is a major public health concern and considered as reemerging in industrialized countries. The present study investigated the prevalence of giardiosis in 202 sheltered dogs using PCR. The infection rate was 33.2% (67/202); Gyeongsangbuk-do and Daejeon showed 25.7% (39/152, P or =1 year of age which showed only 27.4% positive rate, 61.8% (P<0.001) of the total samples collected from young animals (<1 year of age) were positive for G. intestinalis. A significantly higher prevalence in symptomatic dogs (60.8%, P<0.0001) was observed than in asymptomatic dogs (23.8%). Furthermore, the analysis of nucleotide sequences of the samples revealed that G. intestinalis Assemblages A and C were found in the feces of dogs from Gyeongsangbuk-do and Daejeon. Since G. intestinalis Assemblage A has been known to infect humans, our results suggest that dogs can act as an important reservoir of giardiosis in Korea. Hence, hygienic management should be given to prevent possible transmission to humans.

Frecuencia y fuentes de Blastocystis sp . en niños de 0 a 5 años de edad atendidos en hogares infantiles públicos de la zona urbana de Calarcá, Colombia / Blastocystis sp . frequency and sources among children from 0 to 5 years of age attending public day care centers in Calarcá, Colombia

Introducción. No se han descrito las fuentes potenciales de infección por Blastocystis sp . en Colombia. Objetivos. Estimar la frecuencia de Blastocystis sp . y explorar posibles asociaciones entre la infección, las manifestaciones clínicas y algunas fuentes ambientales. Materiales y métodos. Se llevó a cabo un estudio descriptivo con una población de 1.993 menores de 5 años (lactantes y preescolares) de estratos socioeconómicos 1 y 2, atendidos en hogares infantiles de Calarcá, Colombia. Se calculó una muestra de 275 y se seleccionó aleatoriamente a los participantes en 10 % de los hogares infantiles. Se practicaron exámenes coprológicos y encuestas y se tomaron muestras para la identificación del parásito en heces, uñas, animales domésticos y algunas fuentes ambientales. Se hicieron preparaciones en fresco con lugol al 1 % y se utilizó una técnica de concentración con formol-éter. Se estimaron prevalencias y razones de momios; para las variables cualitativas se utilizó el test de ji al cuadrado y, para las cuantitativas, la prueba t de Student. Resultados. La prevalencia de infección en los niños fue de 57,5 %. Hubo asociación estadísticamente significativa entre la presencia del parásito en heces y su hallazgo en recipientes de agua de panela (OR=1,70; IC 95% 1,05-2,79), en los pisos de madera o de tierra en la vivienda (OR=3,43; IC 95% 1,12-10,48), y en alimentos diferentes a la leche en el tetero (OR=3,23; IC 95% 1,41-4,41); y se encontró una prevalencia alta sin asociación en muestras de uñas (OR=1,62; IC 95% 0,99-2,67). La diarrea fue más frecuente en niños con Blastocystis sp. (45 %) que en aquellos sin el parásito (33 %) (OR: 1,95; IC 95% 0,99-2,77) (p<0,05). Conclusiones. Blastocystis sp . se asoció significativamente con síntomas de diarrea en los niños menores de 5 años y se encontró distribuido ampliamente en el ambiente y en el agua. Se requeriría determinar si hay huéspedes específicos para genotipos patógenos por medio de técnicas moleculares.

Introduction: There are no reports of the potential sources of Blastocystis sp . in Colombia. Objectives: To estimate the frequency of Blastocystis sp . and explore possible associations among infection, clinical manifestations and environmental sources. Materials and methods: A descriptive study was conducted; a representative sample was calculated from a population of 1,993 children less than 5 years old of the lowest socioeconomic levels (1 and 2) attending day care centers in Calarcá, Colombia. The calculated sample size was 275 children, who were selected randomly in 10 % of the centers. Stool testing, questionnaires and sampling to identify the parasite in feces, nails, pets and environmental sources, were performed. Fresh preparations were made with 1% iodine solution, and a concentration technique with formalin-ether was used. Prevalence and odd ratios were estimated; the chi-square test was utilized for qualitative variables, and Student´s t for the quantitative ones. Results: The prevalence of infection in children was of 57.5%. A statistically significant association was found between the Blastocystis sp . positive stool tests and the presence of the parasite in containers of sugar cane beverage (OR=1.70; 95% CI: 1.05-2.79), wood or ground floors (OR=3.43; 95% CI: 1.12-10.48) and in foods other than bottled milk (OR=3.23; 95% CI: 1.41-4.41) . A non-significant high prevalence was found in nails (OR=1.62; 95% CI: 0.99-2.67), as well as a significantly higher prevalence of diarrhea (OR=1.95; 95% CI: 0.99-2.77) in children with Blastocystis sp . (45%) as compared with those without the parasite (33%; p<0.05). Conclusions: Blastocystis sp . showed a significant association with diarrhea symptoms in children 0 to 5 years old and was widely distributed in the environment and in water. It is necessary to determine if there are specific hosts with pathogenic potential through molecular techniques.

Genotipos de Giardia duodenalis en muestras de niños de las guarderías del Instituto Colombiano de Bienestar Familiar y de perros en Ibagué, Colombia / Giardia duodenalis genotypes found in the Instituto Colombiano de Bienestar Familiar day care centers and dogs in Ibagué, Colombia

Introducción. Se han descrito ocho genotipos de Giardia duodenalis, del A al H. Los genotipos A y B se han aislado de humanos y de una gran variedad de mamíferos; sin embargo, los genotipos del C al H han mostrado mayor especificidad de huésped. Objetivo. Identificar los genotipos de G. duodenalis a partir de quistes obtenidos en heces de niños de las guarderías del Instituto Colombiano de Bienestar Familiar (ICBF) y de perros en Ibagué, mediante PCR-RFLP de los genes de la beta giardina y la glutamato deshidrogenasa. Materiales y métodos. Los quistes de las muestras positivas para G. duodenalis fueron sometidos a concentración; se extrajo su ADN y se efectuó el análisis de PCR-RFLP de los genes de la beta giardina y de la glutamato deshidrogenasa. Como control positivo se utilizó la cepa MHOM/CO/04/G40 procedente del Grupo de Parasitología del Instituto Nacional de Salud. Resultados. De las muestras tomadas de niños, 11/23 (48 %) correspondieron al genotipo A y, 12/23 (52 %), al genotipo B. Cuatro muestras de perros presentaron los genotipos C y D, específicos de este huésped. Conclusiones. En los niños solamente se encontraron los genotipos asociados a infecciones humanas (AII, BIII y BIV) y en los perros, los genotipos específicos para este huésped (C y D). Debido al reducido tamaño de las muestras analizadas provenientes de perros, y dado que estos no estuvieron en contacto con los niños de las guarderías del ICBF, no fue posible determinar una interacción entre el ciclo de transmisión de los humanos y el de los animales.

Introduction: Eight Giardia duodenalis genotypes (A-H) have been described to date. Genotypes A and B have been isolated from humans and a wide range of mammals; however, genotypes C-H have shown greater host specificity. Objective: Identifying G. duodenalis genotypes from cysts in faeces obtained from children attending the Instituto Colombiano de Bienestar Familiar (ICBF) day care centres and from dogs in Ibagué by PCR-RFLP targeting both the b -giardin and glutamate dehydrogenase genes. Materials and methods: Cysts from G. duodenalis positive samples were concentrated, DNA was extracted and the b -giardin and glutamate dehydrogenase genes were analysed by PCR-RFLP. The MHOM/CO/04/G40 strain was used as positive control (this was obtained from the Grupo de Parasitología at the Instituto Nacional de Salud ). Results: Of the total human samples, 11/23 (48%) were genotyped as A and 12/23 (52%) as B; PCR-RFLP revealed that four canine samples were genotypes C and D, these being host-specific. Conclusions: Only genotypes associated with human infection (AII, BIII and BIV) were found in the children and host-specific genotypes were observed in canines (C and D). No interaction could be established between animal and human transmission cycles due to the small canine sample size and as the former did not come into contact with children attending ICBF day-care centres.

Atualidades sobre giardíase / Updates on giardiasis

A giardíase é uma parasitose intestinal amplamente distribuída pelo mundo, com alta prevalência em países em desenvolvimento, inclusive o Brasil. Embora seja uma infecção com bom prognóstico, pode apresentar gravidade em pessoas com desnutrição, fibrose cística ou algumas imunodeficiências. Este artigo tem como objetivo atualizar os principais aspectos da giardíase.

Giardiasis is an intestinal parasite widely distributed around the globe with high prevalence in developing countries, including Brazil. Although it is an infection with a good prognosis may present serious in people with malnutrition, cystic fibrosis or certain immunodeficiencies. The aim of this paper is to perform an update on key aspects of giardiasis.

Caracterização dos mecanismos de microvesiculação de trofozoítos de Giardia intestinalis e determinação do papel das microvesículas na interação com células hospedeiras / Characterization of microvesiculation mechanisms of Giardia instestinalis trophozoites and determination of the microvesicles role in the interaction with host cells

Giardia intestinalis (G. intestinalis) é o parasita gastrointestinal mais comum que coloniza o trato intestinal humano onde permanece extracelular e aderido às células intestinais. O parasita tem uma distribuição mundial, causando um número estimado de 2.8x108 casos por ano e recentemente a doença foi incluída como parte da Iniciativa das Doenças Negligenciadas da Organização Mundial de Saúde. As manifestações clínicas da giardíase são variáveis, e vão desde a ausência de sintomas até diarreias agudas ou crônicas. Adicionalmente, estudos recentes indicam que distúrbios gastrintestinais funcionais, tais como a síndrome do intestino irritável, e o déficit de crescimento em crianças podem ser associados com a infecção por G. intestinalis. Apesar da alta prevalência e das consequências desta doença, os mecanismos fisiopatológicos subjacentes na giardíase ainda permanecem incompreendidos. Os trofozoítos causam a doença sem penetrar no epitélio intestinal, nem entrar na corrente sanguínea e sem secretar nenhuma toxina conhecida. Nos últimos anos, tem sido descrito que as vesículas extracelulares podem participar na interação parasita-célula hospedeira. As vesículas extracelulares podem ser: microvesículas (MVs) e derivadas da membrana plasmática; exosomos, pequenas vesículas originadas a partir de membranas de endossomos; e corpos apoptóticos contendo material do núcleo celular. As MVs têm sido mostradas como importantes fatores na interação parasita-célula hospedeiraNo presente trabalho, foi utilizada uma combinação de metodologias, incluindo citometria de fluxo, microscopia de fluorescência, proliferação celular, análises de proteoma e ensaios de aderência celular para investigar o papel das microvesículas liberadas por trofozoítos de G. intestinalis nas propriedades patogênicas deste parasita.

Demonstramos que G. intestinalis produz e secreta microvesículas com exposição superficial de fosfatidilserina. Além disso, o processo de liberação de MVs é dependente do tempo e da concentração de cálcio, envolve microdomínios de membrana e as microvesículas contêm RNA de baixo peso molecular. Observamos também que os microdomínios de membrana estão envolvidos na adesão do parasita à células Caco-2. Nossa análise proteômica preliminar sugere presença de componentes do citoesqueleto, alfa giardinas, enzimas metabólicas e proteínas variáveis de xi superfície (VSP) nas MVs isoladas de G. intestinalis. Foi demonstrado também que as MVs de G. intestinalis interagem com as células do hospedeiro aumentando a proliferação destas e incrementado também o número de trofozóitos aderidas à estas células. O presente estudo é o primeiro a sugerir um papel potencial para as microvesículas de G. intestinalis na colonização do hospedeiro. Uma melhor compreensão do papel das MVs liberadas pelo parasita na interação com a célula hospedeira poderá fornecer novas perspectivas sobre patogênese e possivelmente novas ferramentas para o diagnóstico e a terapia da doença.

Giardia intestinalis (G. intestinalis) is the most common gastrointestinal parasite thatcolonizes the human intestinal tract where it remains extracellular and adheres to intestinalcells. The parasite has a global distribution causing an estimated 2.8x108cases per year andthe illness was recently included in the World Health Organization Neglected DiseaseInitiative. Clinical manifestations of giardiasis are quite variable, and range from the absenceof symptoms to acute or chronic diarrhea. Aditionally, recent studies indicate that functionalgastrointestinal disorders, such as irritable bowel syndrome, and failure of children to thrivecan be associated with G. intestinalis infection. Even though the high prevalence andconsequences of this disease, pathophysiological mechanisms underlying symptomaticgiardiasis remain incompletely understood. Trophozoites cause disease without penetratingthe intestinal epithelium, entering the bloodstream or secreting toxins. In recent years it hasbeen described that extracellular vesicles could participate in parasite-host cell interaction.The extracellular vesicles may be: microvesicles (MVs) and derived from the plasmamembrane; exosomes, small vesicles originated from endosomal limiting membrane; andapoptotic bodies containing nuclear material. MVs have been shown to be important factors inthe parasite-host cell interaction. Here, we used a combination of methodologies includingflow cytometry, fluorescence microscopy, cell proliferation, proteomics analysis and celladherence assays to investigate the role of released microvesicles from G. intestinalistrophozoites on the pathogenic properties of this parasite.

We have found that G. intestinalisproduces and secretes microvesicles with superficial exposition of phosphatidilserine.Additionally, the shedding process was calcium and time-dependent, involves membranemicrodomains and the microvesicles contain low-molecular weight RNA. We also observedthat membrane microdomains are involved in parasite attachment to Caco-2 cells. Ourpreliminary proteomic analysis suggested the presence of cytoskeleton components, alphagiardins, metabolic enzymes and variant-specific surface protein (VSP) in the isolated MVsfrom G. intestinalis. We demonstrate that G. intestinalis microvesicles interact with host cellsxiiiincreasing their proliferation and augmenting the number of trophozoites adhered to thesecells. The present study is the first to suggest a potential role for G. intestinalis microvesiclesin host cell colonization. A better understanding of the role of the released microvesicles bythe parasite on the host-cell interaction will provide insights into pathogenesis and possiblynew tools for diagnosis and therapy.

Giardia lamblia: diagnóstico com o emprego de métodos microscópicos e Enzyme-linked Immunosorbent Assay (ELISA) / Giardia lamblia: diagnosis using microscopic methods and enzyme-linked immunosorbent assay (ELISA)

O protozoário Giardia lamblia é um dos agentes etiológicos de diarreia em crianças no Brasil.Seu diagnóstico pode tornar-se difícil em consequência da baixa sensibilidade dos métodosusualmente empregados e por causa da eliminação intermitente dos cistos pode produzir resultadosfalso-negativos. Por essa razão, foi desenvolvido um ensaio imunoenzimático (ELISA) parapesquisa de antígenos de G. lamblia em fezes. Este imunoensaio tem sido descrito na literatura comoum método simples, sensível e específico quando aplicado para o diagnóstico de diversas parasitoses.Assim, este estudo objetivou comparar a técnica de ELISA com os métodos coproscópicos decentrífugo-sedimentação (Técnica de Ritchie) e centrífugo-flutuação (Técnica de Faust), visandodemonstrar a importância de um método com maior sensibilidade. Foram examinadas 158 amostrasde fezes de crianças, de 0 a 12 anos, em uma creche municipal pública de Rio Grande, no RioGrande do Sul, Brasil. Os resultados referentes à comparação entre as técnicas mostraram que atécnica de ELISA tem 3,0 vezes mais chances de detectar amostras positivas de G. lamblia que ométodo de centrífugo-flutuação. Quando comparada com o método de centrífugo-sedimentação,a técnica de ELISA demonstrou ter 3,4 vezes mais chances de detectar amostras positivas para G.lamblia.Concluiu-se que a técnica de ELISA desenvolvida mostrou-se mais eficiente que as técnicasadotadas na rotina laboratorial para o diagnóstico desta parasitose, podendo ser aplicada tanto parao diagnóstico individual como em avaliações epidemiológicas, já que permite o processamento devárias amostras simultaneamente.

The protozoan Giardia lamblia is one of the etiological agents of diarrhea in children in Brazil, anddiagnosis may be difficult due to low sensitivity of the methods commonly used, due the intermittentliberation of cysts, which may lead to false-negative results. Thus, an enzyme-linked immunosorbentassay (ELISA) was developed for detection of G. lamblia antigens in fecal samples, consideringthat this immunoassay has been described to be simple, sensitive and specific when applied todiagnose various parasitic diseases. Thus, this study aimed to compare the ELISA technique withsingle stool sample to examination methods using centrifugal sedimentation (Ritchie technique) andcentrifugation-flotation (Faust technique), intending to demonstrate the importance of a method withgreater sensitivity. Fecal samplesfrom a total of 158 children aged 0-12 years, were examined in apublic municipal nursery in the city of Rio Grande, Rio Grande do Sul, Brazil. The comparative resultsof the investigated techniques showed that ELISA has 3.0 times more chance than centrifugationflotation,and 3.4 times more chance than centrifugal sedimentation to detect positive samples ofG. lamblia. Overall, it was concluded that the ELISA was more efficient than the routine laboratorytechniques for the diagnosis of giardiasis, and it may be used for both individual and epidemiologicalassessments, as the technique allows for processing of multiple samples simultaneously.

Variaciones en las manifestaciones clínicas de la giardiosis en pacientes pediátricos hospitalizados, según grupos de edades / Clinical features of giardiasis in different age groups of pediatric in-patients

It has been suggested that the clinical features of giardiasis might vary in patients of different age groups. Objective: To compare clinical presentation of giardiasis in children less than 5 years of age and older children. Methods: A retrospective study of patients hospitalized with giardiasis during 2007 was performed. The clinical features of the two age groups were compared. Additionally, length of stay was analyzed. Results: In total, 170 patients were included. In children ≥ 5 years of age, abdominal pain and urticaria were significantly more frequent (OR=9.46; 95%CI: 4.35-20.52,P5=0.000+ and OR=11.0; 95%CI: 1.205-101.11, P=0.023, respectively). Diarrhoea was more frequently found in children younger than 5 years (OR=6.45; IC 95%: 3. 12-13.37, P=0.000+). The frequencies of other symptoms were similar. Length of stay was significantly higher in children under 5 years of age. Discussion and conclusions: Clinical presentations differed in some aspects among the examined age group of our paediatric patients. Our finding might be of importance for an early recognition of giardiasis, which is essential for an accurate diagnosis and a prompt treatment.

La giardiosis es una enfermedad frecuente a escala internacional. Se ha sugerido por algunos autores que su presentación clínica puede variar con la edad. Objetivo: Comparar las manifestaciones clínicas de la giardiosis en los niños hospitalizados bajo 5 años de edad con las de niños de 5 años o más. Métodos: Estudio retrospectivo realizado en el Hospital Pediátrico de Centro Habana durante el año 2007. Las manifestaciones clínicas fueron extraídas utilizando un formulario prediseñado y separadas de acuerdo a los grupos de edades estudiados. Adicionalmente, se extrajo la estadía hospitalaria. Resultados: Se incluyeron 170 pacientes. Los niños de 5 y más años de edad manifestaron con mayor frecuencia dolor abdominal (OR = 9,46; IC 95%: 4,35-20,52, p = 0,000+) y urticaria (OR = 11,0; IC 95%: 1,205-101,11, p = 0,023), mientras que la diarrea se encontró más frecuentemente bajo 5 años de edad (OR = 6,45; IC 95%: 3,12-13,37, p = 0,000+). En el resto de las manifestaciones clínicas no se encontraron diferencias significativas en sus frecuencias entre ambos grupos de edades (p > 0,05). La estadía hospitalaria fue significativamente más prolongada entre los pacientes bajo 5 años de edad. Discusión y conclusiones: Las manifestaciones clínicas pueden variar en algunos aspectos entre los diferentes grupos de edades pediátricas. Su rápido reconocimiento es esencial con el fin de arribar a un diagnóstico preciso y al tratamiento oportuno.

High occurrence of giardiasis in children living on a 'landless farm workers' settlement in Araras, São Paulo, Brazil / Alta ocorrência de giardíase em crianças do Assentamento Sem Terra, Araras, São Paulo, Brasil

Enteric parasitosis remains an important public health problem in many areas around the world including in Brazil, and it is frequently associated with poverty and lack of sanitation facilities. Research carried out over the course of a year revealed that 96.6% (28/29) of children randomly selected from a 'landless farm workers' settlement in Araras, São Paulo, aged 4 - 15 years, presented Giardia intestinalis cysts. After referral to the neighborhood Health Office, all the children received tinidazole, given as a single dose of 50 mg/kg and 12 months later, new fecal samples were collected and analyzed. Despite the low adherence to the study, a high percentage (64.3% - 9/14) of the children remained positive for the parasite. This study showed a high positivity of giardiasis in child residents of the settlement, even after treatment; adults were not sensitized to the study and did not collected and/or deliver children fecal samples. The precarious living conditions are consistent with a high susceptibility to parasitic diseases, suggesting that the treatment of the infected individuals without identifying and eradicating the means of contamination is simply a palliative measure.

Enteroparasitoses continuam a ser um importante problema de saúde pública em muitas áreas ao redor do mundo, bem como no Brasil, e está frequentemente associada com a pobreza e à falta de saneamento básico. Pesquisa realizada em um ano revelou que 96,6% (28/29) das crianças com idades entre quatro e 15 anos, recrutadas aleatoriamente no Assentamento Sem Terra em Araras, São Paulo, apresentaram cistos de Giardia intestinalis. Após o encaminhamento ao Posto de Saúde do bairro, todos receberam tinidazol, dose única de 50 mg/kg. Após 12 meses, novas amostras de fezes foram coletadas e analisadas. Apesar da baixa adesão ao estudo, um percentual elevado (64,3% - 9/14) de crianças permaneceu positivo para o protozoário. Este estudo mostrou alta positividade de giardíase nas crianças moradoras do assentamento, mesmo após o tratamento; indivíduos adultos não se mostraram sensibilizados com o estudo e não coletaram e/ou entregaram amostras fecais dos filhos; e o tratamento dos indivíduos infectados, sem identificação e erradicação das formas de contaminação, só funciona como medida paliativa.

Giardia lamblia e alergia respiratória: estudo em uma amostra de crianças de área urbana com frequência elevada da protozoose / Giardia lamblia and respiratory allergies: a study of children from an urban area with a high incidence of protozoan infections

OBJETIVO: Uma elevada incidência de enteroparasitoses é encontrada em regiões urbanas do nordeste brasileiro. As infecções por Giardia lamblia têm sido relacionadas com aumento da prevalência de alergias cutâneas e gastrointestinais. Contudo, ainda existe pouca informação sobre a associação entre a giardíase e doenças alérgicas das vias aéreas. Diante disso, o presente estudo se propôs a verificar a relação entre a infecção por G. lamblia em crianças de área urbana e reatividade alérgica respiratória. MÉTODOS: O estudo incluiu 110 pacientes, de ambos os sexos e idades, entre 5 e 15 anos. Os pacientes foram submetidos a questionários de avaliação dos sintomas clínicos, testes cutâneos de leitura imediata e exames coproparasitológicos e sorológicos. RESULTADOS: Foi verificada uma frequência elevada de crianças infectadas por G. lamblia (45%, 50/110). A infecção pelo protozoário não foi associada com maior risco de alergias respiratórias (p = 0,075), elevação de IgE total (p = 0,701), IgE específica (p = 0,250) ou teste cutâneo positivo para diferentes alérgenos ambientais (p = 0,239). CONCLUSÃO: O estudo demonstrou que a presença dos sintomas de asma, atopia cutânea e marcadores sorológicos não foram associados com a presença de infecção pela G. lamblia nessa amostra de crianças.

OBJECTIVES: There is a high incidence of intestinal parasite infection in urban areas in the Northeast of Brazil. Giardia lamblia infections have been associated with increased prevalence of cutaneous allergies and gastrointestinal disorders. However, little is known about the relationship between giardiasis and allergic diseases of the airways. The present study aimed to investigate the possible association between respiratory allergic diseases and infections by G. lamblia in children from urban areas. METHODS: This study recruited 110 patients of both sexes aged 5-15 years. Patients were administered a questionnaire evaluating clinical symptoms and were given skin tests, parasite tests and serum tests. RESULTS: A high incidence of G. lamblia was observed (45%, 50/110). Infections by this protozoan were not associated with increased risk of respiratory allergy (p = 0.075), high total IgE levels (p = 0.701), positive specific IgE tests (p = 0.250), or positive skin tests for a range of environmental allergens (p = 0.239). CONCLUSION: This study demonstrated that symptoms of asthma, skin allergy and serum markers were not associated with G. lamblia infections in this sample of children from urban areas.

Prevalencia y factores de riesgo de Cryptosporidium spp. y Giardia spp. en terneros de ganado lechero de la zona noroccidental de la Sabana de Bogotá / Cryptosporidium spp. and Giardia spp. prevalence and risk factors in dairy calves of the north-western zone of the Bogota Savanna

Objetivo Estimar la prevalencia de Cryptosporidium spp. y Giardia spp. en terneros de 0 a 2 meses de ganado lechero de la zona noroccidental de la Sabana de Bogotá. Se estimaron los factores de riesgo de la producción lechera que puedan incurrir en la infección de personas y animales. Métodos Estudio de corte transversal, mediante la toma de materia fecal de terneros. Se determinó la prevalencia de punto para Giardia spp. y Cryptosporidium spp. a través los resultados de los coprológicos (Ritchie para Giardia spp. y Ziehl-Neelsen modificada para Cryptosporidium spp.). Se calcularon Odds Ratio para establecer los factores de riesgo asociados entre estos dos géneros de protozoarios y el manejo de las Buenas Prácticas Ganaderas. Resultados Se evaluaron 33 fincas dedicadas a la producción lechera, donde se muestrearon 308 terneros. La prevalencia para Giardia spp. fue de 37,3 %, 115 animales positivos y para Cryptosporidium spp. fue de 4,9 % 15, animales positivos. Conclusión Existe un foco de Giardia spp. y Cryptosporidium spp. en el noroccidente de la Sabana de Bogotá, del cual no se tenía conocimiento previo. La prevalencia de Giardia spp. para la región estudiada, está en el límite alto del rango reportado para Sudamérica. En el caso de Cryptosporidium spp. la situación es distinta, la prevalencia se encuentra en el limite bajo del rango reportado para Sudamérica. Los factores de riesgo asociados a Giardia spp. y Cryptosporidium spp. en las explotaciones lecheras del noroccidente de la Sabana de Bogotá, dependen de Buenas Prácticas Ganaderas.

Objective The present study was aimed to establishing Cryptosporidium spp. and Giardia spp. prevalence in 0 to 2 months old dairy calves of the north-western zone of the Bogota Savanna. In addition, associated factors related to a failure in Good Practices of Livestock could incur in human and animal infection. Methods This was a cross-sectional study; calves' fecal samples were used. Farms' Good Practices of Livestock were observed by means of an observation blank. Giardia spp. and Cryptosporidium spp. prevalence was determinate by means of laboratory results (Ritchie for Giardia spp. and modified Ziehl-Neelsen for Cryptosporidium spp.). Odds Ratios (OR) were calculated in association between this two genera of protozoa and Good Practices of Livestock. Results Thirty three dairy farms were evaluated, where fecal samples of 308 calves were taken. Giardia spp. prevalence was 37.7 %, 115 infected animals; Cryptosporidium spp. prevalence was 4.9 %, 15 infected animals. Conclusion There is an important Giardia spp. and Cryptosporidium foci in the north-western zone of the Bogota Savanna, without a previous knowledge. Giardia spp. prevalence for this zone is in the highest rank reported for South-America and Cryptosporidium spp. prevalence is in en the lowest one. Associated risk factors of Giardia spp. and Cryptosporidium spp. in dairy farms of the north-western zone of the Bogota Savanna depend of a Good Practices of Livestock performance.

Prevalência da infecção por Helicobacter pylori e de parasitoses intestinais em crianças do Parque Indígena do Xingu / Prevalence of Helicobacter pylori infection and intestinal parasitosis in children of the Xingu Indian Reservation

OBJETIVO: Avaliar a prevalência da infecção por Helicobacter pylori e sua associação com parasitoses intestinais em crianças da comunidade indígena do Parque Indígena do Xingu. MÉTODOS: Foram incluídas 245 crianças indígenas entre 2 e 9 anos, de seis aldeias da região do rio Xingu, afluente do Amazonas. H. pylori foi detectado pelo teste respiratório com ureia-13C. Foram coletadas amostras de ar expirado, em jejum e 30 minutos após a ingestão de 50 mg de ureia-13C diluída em 100 mL de água aromatizada com suco de maracujá. Foram coletadas amostras de fezes de 202/245 (82,4 por cento) crianças para exame protoparasitológico. RESULTADOS: A prevalência do H. pylori foi de 73,5 por cento. Foi observada associação significativa do H. pylori com maior idade entre as diferentes aldeias e etnias. Resultaram positivas para a presença de parasitas 97,5 por cento (198/202) das amostras de fezes, sem associação com a infecção por H. pylori. Encontrou-se, na análise multivariada, uma relação entre a infecção por giárdia e o H. pylori. As etnias Kisêjê [odds ratio (OR) = 3,36] e Kaibi (OR = 4,00), e as aldeias Tuiararé (OR = 8,10), Ngojwere (OR = 4,10), Capivara (OR = 4,88), Diauarum (OR = 1,85) e Pavuru (OR = 1,40) foram fatores de risco para a infecção por H. pylori. CONCLUSÕES: Foi encontrada alta prevalência de H. pylori e de parasitose intestinal em crianças nas comunidades presentemente investigadas. No entanto, houve diferença significativa na prevalência do H. pylori entre as diversas aldeias estudadas. Verificou-se associação entre a presença de giárdia e a infecção por H. pylori.

OBJECTIVE: To evaluate the prevalence of Helicobacter pylori infection and its association with intestinal parasitoses in children from indigenous communities of the Xingu Indian Reservation, in Brazil. METHODS: A total of 245 Native Brazilian children between 2 and 9 years of age, from six villages of the Xingu River region, a tributary of the Amazon River, were assessed. H. pylori was detected using the 13C-urea breath test. Breath samples were collected at baseline and 30 minutes after ingestion of 50 mg of 13C-urea diluted with 100 mL of water flavored with passion fruit juice and sweetener. Stool samples were collected for the stool ova and parasites exam for 202/245 (82.4 percent) children. RESULTS: The overall prevalence of H. pylori was 73.5 percent. A significant association of H. pylori with increased age was observed among the different villages and ethnic groups. Positive results for the presence of parasites - 97.5 percent (198/202) - from the stool samples collected showed no association with H. pylori. Giardia showed an association with H. pylori in the multivariate analysis. Risk factors for H. pylori infection were observed in Kisêjê and Kaibi ethnic groups (OR [odds ratio] = 3.36 and 4.00, respectively), as well as in Tuiararé, Ngojwere, Capivara, Diauarum, and Pavuru villages (OR = 8.10, 4.10, 4.88, 1.85, and 1.40, respectively). CONCLUSIONS: H. pylori infection is highly prevalent in these communities, as well as intestinal parasitoses. However, there were significant differences in the prevalence of H. pylori among the diverse villages studied. Giardia was closely associated with H. pylori infection.

Parasitos intestinais: elevada prevalência de Giardia lamblia em pacientes atendidos pelo serviço público de saúde da região sudeste de Goiás, Brasil / Intestinal parasites: high prevalence of Giardia lamblia. in patients treated by the public health service in southeast region of Goiás, Brazil

O presente estudo teve como objetivo levantar dados sobre a incidência de parasitos intestinais em pacientes atendidos pelo serviço público no Hospital Municipal de Cumari, Goiás. Os exames parasitológicos foram realizados entre janeiro de 2002 e dezembro de 2008, pelo método Hoffmann, Pons e Janer ou por sedimentação espontânea. Das 1.029 amostras analisadas, 373 (36,2por cento) apresentaram ovos ou cistos de parasitos, entre os quais foram encontradas espécies como: Giardialamblia, Entamoeba coli, Hymenolepis nana e Strongyloides stercoralis. Giardia lamblia merece destaque por ter apresentado elevada prevalência, que se manteve constante durante os seis anos de estudos, e pela elevada incidência encontrada nas diferentes faixas etárias, em média 33,6por cento (n igual 346). Os elevados índices de giardiose podem estar associados a provável contaminação da rede pública de abastecimento de água, visto que este protozoário resiste à ação do cloro adicionado à água tratada. Estaprevalência é semelhante aos dados registrados em outras publicações e, nestes casos, é recomendada aimplementação de políticas públicas de saúde que visem ao controle destas enteroparasitoses.

Prevalence of Cryptosporidium spp. and Giardia spp., spatial clustering and patterns of shedding in dairy calves from Córdoba, Argentina / Prevalência de Cryptosporidium spp. e Giardia spp., distribuição espacial e padrões de eliminação em bezerros de propriedades leiteiras em Córdoba, Argentina

The objectives of this study were to estimate calf and herd prevalence of Cryptosporidium spp. and Giardia spp., the herd prevalence clustering, spatial distribution according to soil type and shedding patterns in dairy calves from Cordoba, Argentina. Six hundred twenty calves younger than 7 weeks of age from 43 dairy herds were sampled. Samples were processed with the formol-ether and modified Ziehl-Neelsen techniques. Univariate analysis and Kruskall-Wallis tests were used. Factors associated were subjected to multivariate analysis with calf shedding intensity as the response variable. Clustering of herd prevalence was assessed by a scan method, and spatial analysis was applied to explore the overlapping of high prevalence herds and soil type. Overall calf prevalence for Cryptosporidium spp. oocysts and Giardia spp. cysts were 19.35 percent (95 percent CI: 16.14; 22.54) and 34.50 percent (95 percent CI: 30.69; 38.34), respectively. Calves younger than two weeks of age were almost four times more likely to be infected with Cryptosporidium, in comparison to older ones (RR: 3.78, 95 percent CI: 2.27; 6.26). Giardia spp. shedding showed a similar age pattern (RR: 1.33, 95 percent CI: 1.02; 1.75). A primary cluster of high Cryptosporidium prevalence was found, and high prevalence herds were located in areas with poor drained soil.

Os objetivos deste estudo foram determinar a prevalência de Cryptosporidium spp. e Giardia spp., a presença de aglomerados, a distribuição espacial de acordo com o tipo de solo e padrões de eliminação de cistos e oocistos em bezerros de propriedades leiteiras em Córdoba, Argentina. Amostras fecais foram colhidas de 620 bezerros com menos de sete semanas de idade, provenientes de 43 propriedades leiteiras e examinadas pelas técnicas de formol-éter e Ziehl-Neelsen modificada. Foram realizadas uma análise univariada e o teste de Kruskal-Wallis e, em seguida, uma análise multivariada com a intensidade de eliminação de cistos e oocistos, como um evento. A presença de aglomerados foi determinada com o método de varredura e a análise espacial foi realizada para explorar a sobreposição de rebanhos com alta prevalência e tipo de solo. A prevalência de Cryptosporidium spp. e Giardia spp. foi de 19,35 por cento (IC 95 por cento: 16,14; 22,54) e 34,50 por cento (IC 95 por cento: 30,69; 38,34), respectivamente. A probabilidade de infecção por Cryptosporidium spp. foi quase quatro vezes maior para bezerros com menos de 2 semanas em comparação com os bezerros mais velhos (RR: 3,78, IC 95 por cento 2,27; 6,26). O mesmo padrão de infecção relacionada à idade foi observado para Giardia spp. (RR: 1,33, IC 95 por cento 1,02; 1,75). Foi encontrado um aglomerado primário com alta prevalência de Cryptosporidium spp., e rebanhos com alta prevalência foram localizados em solos mal drenados.

Prevalence of intestinal parasites in children of homs province

This research aimed to study the prevalence of intestinal parasites in a group of children in Homs province, and determination the percentage of species of the parasites in the infected children. This study, performed between 01/ 01/ 2007 - 31/ 12/ 2009, conducted on 616 children aged between 2-14 years. The results of study showed that the Parasitic infection rate was 34.25% [30.68% by intestinal protozoa 3.57% by intestinal helminths]. The most important parasite was giardia lamblia

Diagnosis of Giardia infections by PCR-based methods in children of an endemic area

The present study was designed to estimate the prevalence of Giardia infection in preschool- and school-aged children living in an endemic area. Fecal samples from 573 children were processed by zinc sulfate centrifugal flotation, centrifugal sedimentation (using a commercial device for fecal concentration - TF-Test kit®) and polymerase chain reaction (PCR)-based methods. Of the stool samples assessed, 277 (48.3 percent) were positive for intestinal parasites and/or commensal protozoa. Centrifugal flotation presented the highest diagnostic sensitivity for Giardia infections. The kappa index revealed that both coproparasitological techniques closely agreed on the Giardia diagnosis (86 percent) versus satisfactory (72 percent) and poor (35 percent) concordances for commensal protozoan and helminth infections, respectively. Concerning Giardia molecular diagnosis, from the 71 microscopy-positive samples, specific amplification of gdh and tpi fragments was noted in 68 (95.7 percent) and 64 (90 percent) samples, respectively. Amplification of gdh and tpi genes was observed, respectively, in 95.7 percent and 90 percent of microscopy-positive Giardia samples. For 144 microscopy-negative samples, gdh and tpi gene amplification products were obtained from 8.3 percent and 35.9 percent samples, respectively. The agreement between these genes was about 40 percent. The centrifuge-flotation based method was the most suitable means of Giardia diagnosis assessed in the present study by combining accuracy and low cost.