Perfil de desempenho de técnicas coproscópicas Coproplus® e Hoffman, Pons e Janner no diagnóstico de giardíase / Performance profile of coproscopic techniques Coproplus® and Hoffman, Pons and Janner in the diagnosis of giardiasis / Perfil de rendimiento de las técnicas coproscópicas Coproplus® y Hoffman, Pons y Janner en el diagnóstico de giardiasis

Justificativa e Objetivos: Os parasitas intestinais representam um problema de saúde pública no Brasil, e sua identificação é feita rotineiramente, por meio de várias técnicas diagnósticas. Muitas dessas técnicas são criticadas por suas limitações, como a de Hoffman, Pons e Janner. Considerou-se avaliar o grau de sensibilidade diagnóstica dessa técnica em comparação ao método coproscópico de coleta e filtragem Coproplus®, uma vez que esta metodologia também é baseada na concentração de estruturas parasíticas e é uma adaptação prática aos métodos usuais, pois não há documentos diagnósticos de protozoários. Métodos: A análise gráfica pelo método de Bland-Altman mostrou que há concordância entre os dois métodos de identificação dos cistos avaliados, ao traçar as diferenças entre o número de cistos contra as médias de ambos os valores. Resultados: Verificou-se que, para os protozoários, o uso de apenas um método parasitológico de Hoffman, Pons e Janner não é suficiente para identificar todas as amostras. Conclusão: Os métodos têm se mostrado eficazes na identificação de parasitas intestinais, mas nem todos os agentes foram identificados simultaneamente em ambas as técnicas e números de cistos, o que leva à conclusão de que uma técnica pode complementar a outra.(AU)

Background and Objectives: Intestinal parasites are a public health problem in Brazil. The identification of parasites in feces is routinely performed by several diagnostic techniques; many of these methods are still criticized for their limitations such as the Hoffman, Pons, and Janner one. We thus considered valid to evaluate the degree of diagnostic sensitivity of this technique in Coproplus® coproscopic collecting and filtering method, since this methodology is also based on the concentration of parasitic structures, and this is a practical adaptation to the usual methods, since there are diagnosis documents of protozoa. Methods: The graphic analysis by the Bland-Altman method showed that there is agreement between the two methods of identification of cysts evaluated when plotting the differences between the number of cysts against the means of both values. Results: For protozoa, the use of a single parasitological method ­ Hoffman, Pons and Janner ­ is not sufficient to identify all samples. Conclusion: The analyzed methods were effective in identifying intestinal parasites, but not all agents were identified simultaneously in both techniques and numbers of cysts, which leads to the conclusion that the two techniques are complementary.(AU)

Justificación y Objetivos: Los parásitos intestinales son un problema de salud pública en Brasil, y la identificación de parásitos se realiza de forma rutinaria mediante diversas técnicas de diagnóstico. Incluso con la existencia de numerosos métodos de diagnóstico, muchos aún son criticados por sus limitaciones, como el de Hoffman, Pons y Janner. Se consideró oportuno evaluar el grado de sensibilidad diagnóstica de esta técnica en el método de coprofia de recolección y filtro Coproplus®, ya que esta metodología también se basa en la concentración de estructuras parásitas y es una adaptación práctica a los métodos habituales, y no hay documentos de diagnóstico de protozoos. Métodos: El análisis gráfico por el método de Bland-Altman mostró que existe una concordancia entre los dos métodos de identificación de los quistes evaluados al rastrear las diferencias entre el número de quistes y los promedios de ambos valores. Resultados: Se ha encontrado que, para los protozoos, el uso de un solo método parasitológico (Hoffman, Pons y Janner) no es suficiente para identificar todas las muestras. Conclusión: Se ha demostrado que los métodos son eficaces para identificar parásitos intestinales, pero no todos los agentes se han identificado simultáneamente en las técnicas y en el número de quistes, lo que lleva a la conclusión de que una técnica puede complementar a la otra.(AU)

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 animals the 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 presente survey has had the purpose to investigate the occurrance 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 infecction on the rate of (9/37), being. 5,4% (2/37) positive to Cryptosporidiumspp. and 18,91% (7/37) positive to Giardia spp., what shows that no amimals had both infections at the same time. Cryptosporidium spp. and Giardia spp., are zoonotic enteroparasites that have been taking place as an emmerging problem to public health. Theese species of protozoa may reach high levels of frequency in regions where the basic sanitation conditions are precarious, promoting outbraks 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 reserach strenghtens 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.

An Improved PCR-RFLP Assay for Detection and Genotyping of Asymptomatic Giardia lamblia Infection in a Resource-Poor Setting

Laboratory workers, in resource-poor countries, still consider PCR detection of Giardia lamblia more costly and more time-consuming than the classical parasitological techniques. Based on 2 published primers, an in-house one-round touchdown PCR-RFLP assay was developed. The assay was validated with an internal amplification control included in reactions. Performance of the assay was assessed with DNA samples of various purities, 91 control fecal samples with various parasite load, and 472 samples of unknown results. Two cysts per reaction were enough for PCR detection by the assay with exhibited specificity (Sp) and sensitivity (Se) of 100% and 93%, respectively. Taking a published small subunit rRNA reference PCR test results (6%; 29/472) as a nominated gold standard, G. lamblia was identified in 5.9% (28/472), 5.2%, (25/472), and 3.6% (17/472) by PCR assay, RIDA® Quick Giardia antigen detection test (R-Biopharm, Darmstadt, Germany), and iodine-stained smear microscopy, respectively. The percent agreements (kappa values) of 99.7% (0.745), 98.9% (0.900), and 97.7% (0.981) were exhibited between the assay results and that of the reference PCR, immunoassay, and microscopy, respectively. Restriction digestion of the 28 Giardia-positive samples revealed genotype A pattern in 12 and genotype B profile in 16 samples. The PCR assay with the described format and exhibited performance has a great potential to be adopted in basic clinical laboratories as a detection tool for G. lamblia especially in asymptomatic infections. This potential is increased more in particular situations where identification of the parasite genotype represents a major requirement as in epidemiological studies and infection outbreaks.

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.

Intervención para mejorar conocimientos, percepciones y prácticas en relación con el diagnóstico, tratamiento y control de la giardiasis / Intervention to improve knowledge, perceptions and practices in the diagnosis, treatment and control of giardiasis

Objetivo: evaluar los resultados de una intervención para mejorar conocimientos, percepciones y prácticas de los médicos relacionados con el diagnóstico, tratamiento y control de la giardiasis. Métodos: para indagar en los conocimientos, percepciones y prácticas de médicos de familia del municipio Playa, La Habana, en relación con el diagnóstico, tratamiento y control de la giardiasis, se diseñó, validó y aplicó a estos un cuestionario de 27 preguntas. Para atenuar las deficiencias evidenciadas con la aplicación de ese instrumento, se ejecutaron, a modo de intervención, un grupo de acciones de tipo académico. Esas medidas incluyeron la preparación, publicación y distribución gratuita a todos los médicos de un libro sobre giardiasis, así como la impartición de conferencias sobre el tema. Para evaluar los resultados de la intervención, a 6 meses de completada su puesta en práctica, se hizo una segunda aplicación del cuestionario antes mencionado. Resultados: la primera aplicación del cuestionario hizo evidente los conocimientos insuficientes, las percepciones inadecuadas y prácticas incorrectas. Por ejemplo, la media de respuestas correctas a las 19 interrogantes sobre aspectos cognoscitivos fue de 7,69. La segunda aplicación del instrumento permitió conocer de una significativa mejoría de los encuestados en la casi totalidad de los aspectos cognoscitivos, perceptuales y conductuales evaluados. Por ejemplo, la media de respuestas correctas a las preguntas sobre aspectos cognoscitivos resultó significativamente más alta (14,61; p< 0,0001). Conclusión: los resultados de la intervención realizada en el municipio Playa sugieren su extensión al resto del país y demuestran, una vez más, la necesidad de monitorear y actualizar con regularidad los programas de formación de médicos y especialistas en los aspectos relacionados con el diagnóstico, tratamiento y control de las enfermedades parasitarias

Objective: evaluate the results of an intervention aimed at improving physicians' knowledge, perceptions and practices in the diagnosis, treatment and control of giardiasis. Methods: a 27-question survey was designed, validated and given to family doctors from the municipality of Playa, Havana, aimed at inquiring about their knowledge, perceptions and practices in the diagnosis, treatment and control of giardiasis. To make up for deficiencies found in the application of this tool, a number of academic actions were implemented. For example, a book on giardiasis was prepared, published and distributed free-of-charge among all doctors, and lectures on the topic were delivered. Six months after implementation of the intervention, the questionnaire was applied again with the purpose of evaluating the results obtained. Results: the first application of the questionnaire revealed that knowledge was insufficient, perceptions inadequate and practices incorrect. For instance, the mean number of correct answers to the 19 questions on cognitive aspects was 7.69. The second application of the questionnaire showed a significant improvement in practically all the cognitive, perceptual and behavioral aspects evaluated. This time the mean number of correct answers to questions on cognitive aspects was significantly higher (14.61; p< 0.0001). Conclusion: the results obtained from the intervention implemented in the municipality of Playa point to the advisability of its expansion to the rest of the country. They also suggest, once again, the need to regularly monitor and update the contents of training programs for doctors and specialists in relation to the diagnosis, treatment and control of parasitic diseases

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.

Inmunodeficiencia variable común: afectación digestiva de un trastorno sistémico / [Common variable immunodeficiency: digestive involvement of a systemic disease].

Common variable immunodeficiency is characterized by a primary deficiency in antibody production that is clinically manifested by respiratory recurrent infections and gastrointestinal diseases (infectious, inflammatory and neoplastic). Above 50

of the patients have diarrhea and 10

develop idiopathic malabsorption and weight loss. We present the case of a 34-year-old woman submitted to our service for chronic diarrhea, abdominal pain and bloating and history of recurrent respiratory infections since childhood. The laboratory assessment showed severe hypoproteinemia and confirmed low IgG, IgA and IgM levels. Upper gastrointestinal endoscopy and videocapsule endoscopy showed a nodular duodenum with multiple polypoid-like formations all through the small bowel. Histology confirmed chronic duodenitis and Giardia lamblia infection. With the diagnosis of common variable immunodeficiency, monthly intravenous gammaglobulin infusion was initiated and metronidazole was indicated for Giardia lamblia infection achieving excellent clinical and laboratory response.

Breast-Feeding Protects Infantile Diarrhea Caused by Intestinal Protozoan Infections

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-alpha were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-alpha were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-alpha and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.

Sensitive and Rapid Detection of Giardia lamblia Infection in Pet Dogs using Loop-Mediated Isothermal Amplification

Giardia lamblia is recognized as one of the most prevalent parasites in dogs. The present study aimed to establish a loop-mediated isothermal amplification (LAMP) assay for rapid and specific detection of G. lamblia from dogs. The fecal samples were collected and prepared for microscopic analysis, and then the genomic DNA was extracted directly from purified cysts. The concentration of DNA samples of G. lamblia were diluted by 10-fold serially ranging from 10(-1) to 10(-5) ng/microl for LAMP and PCR assays. The LAMP assay allows the amplification to be finished within 60 min under isothermal conditions of 63degrees C by employing 6 oligonucleotide primers designed based on G. lamblia elongation factor 1 alpha (EF1alpha) gene sequence. Our tests showed that the specific amplification products were obtained only with G. lamblia, while no amplification products were detected with DNA of other related protozoans. Sensitivity evaluation indicated that the LAMP assay was sensitive 10 times more than PCR. It is concluded that LAMP is a rapid, highly sensitive and specific DNA amplification technique for detection of G. lamblia, which has implications for effective control and prevention of giardiasis.

Common variable immunodeficiency and isosporiasis: first report case / Imunodeficiência comum variável e isosporíase: primeiro relato de caso

We report a severe case of diarrhea in a 62-year-old female HIV-negative patient from whom Giardia lamblia and Isospora belli were isolated. Because unusual and opportunistic infections should be considered as criteria for further analysis of immunological status, laboratory investigations led to a diagnosis of common variable immunodeficiency (CVID). This is the first reported case of isosporiasis in a patient with CVID and illustrates the importance of being aware of a possible link, particularly in relation to primary immunodeficiency.

Trata-se de relato de caso de uma paciente de 62 anos, sexo feminino, HIV negativo apresentando um quadro grave de diarréia, sendo isolados Giardia lamblia e Isospora belli. Infecções incomuns e oportunistas devem ser consideradas como um sinal para alerta para que se analise o sistema imunológico. O diagnóstico de imunodeficiência de comum variável foi realizado após investigação. Este é o primeiro caso relatado de isosporíase em pacientes com imunodeficiência comum variável e mostra a importância de estar alerta tambem em relação a imunodeficiências primárias.

ELISA y técnica de sedimentación espontánea para el diagnóstico de infección por Giardia lamblia en muestras fecales de niños de Perú / ELISA and spontaneous sedimentation technique for the diagnosis of Giardia lamblia infection in stool samples of Peruvian children

OBJETIVO: Comparar un kit ELISA comercial para coproantígenos y la técnica de sedimentación espontánea en tubo (TSET) para el diagnóstico de Giardia lamblia en muestras fecales de niños de una zona endémica peruana. MATERIAL Y MÉTODOS: Fueron analizadas 174 muestras mediante la TSET y el kit Giardia 2nd Generation ELISA. RESULTADOS: Fueron positivas 51 muestras por ELISA y 49 por TSET. CONCLUSIONES: El ELISA resultó ser altamente sensible y específico, sencillo y rápido; sin embargo, la muy buena concordancia, alta precisión, bajo costo y capacidad para detectar otros enteroparásitos hace que la TSET sea recomendable para el diagnóstico en zonas endémicas del Perú.

OBJETIVE: To compare a commercial coproantigen ELISA kit and the technique of spontaneous sedimentation in tube (TSET) for the diagnosis of Giardia lamblia in fecal specimens from children in a Peruvian endemic area. MATERIAL AND METHODS: 174 fecal samples were analyzed by TSET and 2nd Generation Giardia ELISA kit. RESULTS: 51 samples were positive by ELISA and 49 by TSET. CONCLUSIONS: The ELISA was highly sensitive and specific, simple and fast. However, the very good agreement, high precision, low cost and ability to detect other intestinal parasites makes use of TSET recommended for laboratory diagnosis in endemic areas of Peru.

Giardiasis as zoonosis: between proof of principle and paradigm in the Northwestern region of São Paulo State, Brazil

OBJECTIVE: In order to evaluate the potential zoonotic transmission of Giardia duodenalis, isolates from humans and dogs in the Northwestern region of the São Paulo State, Brazil were characterized based on the β-giardin gene. METHODS: The samples were analyzed by sequencing of the Nested-PCR products. RESULTS: The A1 and A2 subgenotypes were detected in human and dogs. Cysts of assemblage B, C and D have not been found in any isolates studied. CONCLUSIONS: These results are consistent with the view that giardiasis in the largest endemic region of the Brazil should not be seen as a single entity.

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.

Diagnóstico laboratorial da giardiose humana: comparação entre as técnicas de sedimentação espontânea em água e de centrífugo-flutuação em solução de sulfato de zinco / Laboratory diagnosis of human giardiasis: comparison between spontaneous sedimentation in water and zinc sulfate centrifugal flotation

Introdução: A giardiose é uma das enteroparasitoses mais prevalentes no nosso meio e acarreta morbidade de indivíduos e dispêndio de recursos pecuniários. O diagnóstico laboratorial da giardiose é essencial, sendo o exame parasitológico de amostras fecais por microscopia o padrão ouro, a despeito do surgimento de técnicas alternativas. Dada a possível diferença de sensibilidade empregando técnicas de concentração distintas, torna-se necessário uma comparação entre as mesmas. Objetivos: Os objetivos deste estudo foram comparar duas técnicas amplamente utilizadas para o diagnóstico da giardiose e, concomitantemente, caracterizar a população do estudo e avaliar a ocorrência de co-parasitoses. Métodos: As amostras foram coletadas no período de março a maio de 2010 (N =163), sendo provenientes de usuários do Laboratório de Análises Clínicas Prof. Rubens Dantas (LAC, Farmácia, UFRGS, Porto Alegre). As técnicas de concentração das amostras fecais empregadas para o diagnóstico foram a de sedimentação espontânea em água (HPJ) e a centrífugo- flutuação em solução de sulfato de zinco (Faust). Aplicou-se um questionário aos usuários do laboratório para melhor caracterização da população estudada. Resultados: A prevalência total de enteroparasitoses e de giardiose na população estudada foi, respectivamente, de 22,9% e de 10,7% empregando as duas técnicas de concentração. A giardiose foi mais pronunciada em crianças e idosos, principalmente, do gênero masculino. A técnica de Faust (N =11) apresentou maior sensibilidade quando comparada a técnica de HPJ (N =6). Conclusão: A técnica de Faust foi mais sensível para observação de cistos de Giardia lamblia podendo ser uma técnica complementar ao HPJ no diagnóstico deste protozoário.

Background: Giardiosis is one of the most prevalent enteric parasitic diseases in our environment and causes of morbidity and medical costs. The laboratory diagnosis of giardiosis is essential. The parasitological examination of fecal samples using microscopy is the gold standard method of diagnosis, despite of the emergence of alternative techniques. Different diagnostic methods must be compared because of the possible variation in sensitivity using different concentration techniques. Aim: The objectives of this study were to compare the two techniques widely used for diagnosis of giardiosis and, concomitantly, characterize the study population and evaluate the co-occurrence of parasitic diseases. Methods: The samples were collected between March and May 2010 (N =163) from Laboratório de Análises Clínicas Prof. Rubens Dantas (LAC, School of Pharmacy, UFRGS, Porto Alegre). The concentration techniques of fecal samples for diagnosis were spontaneous sedimentation in water (HPJ) and the zinc sulfate centrifugal-flotation (Faust). A questionnaire was completed by the users of the laboratory to better characterize the study population. Results: The prevalence of enteric parasitic diseases and giardiosis in the study population was, respectively, 22.9% and 10.7% using both techniques of concentration. Giardiosis was more pronounced in children and elderly, especially males. The Faust technique (N =11) showed higher sensitivity when compared to the HPJ technique (N =6). Conclusion: The Faust technique was more sensitive to the observation of Giardia lamblia and may be a complementary technique to HPJ.

Conocimientos, percepciones y prácticas de los dermatólogos en relación con la infección por Giardia lamblia / Knowledge, perceptions and practice of dermatologists with respect to Giardia lamblia infection

OBJETIVO: conocer sobre los conocimientos, percepciones y prácticas de los dermatólogos de Ciudad de La Habana en relación con la infección por Giardia lamblia. MÉTODOS: previo consentimiento informado de los dermatólogos de Ciudad de La Habana, a un número próximo al universo de estos (50 de 58), se le aplicó una encuesta sobre conocimientos, percepciones y prácticas en relación con esta parasitosis. La preparación de la encuesta pasó por 4 fases: entrevistas a médicos relacionados con el diagnóstico, tratamiento y control de la giardiasis; preparación de un cuestionario preliminar sobre la base de los resultados de esas entrevistas; sometimiento del instrumento a criterio de expertos; y validación de este mediante su aplicación a un pequeño grupo de galenos. RESULTADOS: se evidenció que en relación con la giardiasis y, de manera particular, con las manifestaciones cutáneas asociadas a esta, los dermatólogos de Ciudad de La Habana mostraban conocimientos insuficientes (de 19 interrogantes que evaluaban aspectos cognoscitivos, la media de respuestas correctas entre todos los participantes fue 10,18), percepciones inadecuadas y prácticas incorrectas. CONCLUSIONES: en la dirección de atenuar estas dificultades se hace necesario una intervención de tipo académica, que haga énfasis en los aspectos formativos relacionados con las enfermedades parasitarias, en general, y la giardiasis, en particular.

OBJECTIVE: to ascertain the level of knowledge, the perceptions and practice of dermatologists in the City of Havana with respect to Giardia lamblia infection. METHODS: with prior informed consent given by the dermatologists from the City of Havana, 50 dermatologists- a number very close to the universe of these experts in the province- were administered a survey of their knowledge, perceptions and practice about this parasitosis. The survey was prepared in 4 phases; that is, interviews to physicians on diagnosis, treatment and control of giardiasis; drafting of a preliminary questionnaire based on the interview results; submission of this instruments to the experts, and finally its validation through its application to a small group of physicians. RESULTS: it was evinced that the dermatologists in the City of Havana had poor knowledge about giardiasis, particularly its cutaneous manifestations (out of 19 questions on cognitive aspects, the correct answer mean was 10,18), inadequate perceptions on this disease and practice was not good. CONCLUSIONS: with the aim of mitigating these difficulties, some academic intervention is needed to make emphasis on the formative aspects related to parasitic diseases in general and giardiasis in particular.