Toxocariasis en niños: análisis de 85 casos en un hospital pediátrico de Argentina / Toxocariasis in children: analysis of 85 cases in a paediatric hospital in Argentina

INTRODUCCIÓN: La toxocariasis es una enfermedad parasitaria ampliamente distribuida. Las formas clínicas descritas son la asintomática (TA), larva migrans visceral (LMV), larva migrans ocular (LMO) y encubierta (TE). OBJETIVOS: Describir las características clínicas, de laboratorio, evolución y tratamiento de los casos y comparar las diversas formas clínicas de presentación. PACIENTES Y MÉTODOS: Análisis retrospectivo de todos los pacientes pediátricos con diagnóstico de toxocariasis atendidos en el Servicio de Infectología del Hospital General de Niños Pedro de Elizalde entre 2012 y 2019. RESULTADOS: Se incluyeron 85 pacientes. El 63,5 % fueron varones y la mediana de edad fue de 60 meses. Cuarenta y nueve pacientes presentaron TA, 14 LMV, 15 LMO y 7 TE. Los pacientes con LMV presentaron menor edad y recuento de eosinófilos más altos. Todos los casos de LMO presentaron mal pronóstico visual. Se indicó tratamiento con albendazol en todos los casos de LMV, en los casos activos de LMO, en 4 TE y en 3 TA. CONCLUSIÓN: Este estudio representa uno de los más grandes llevados a cabo en el país. Todas las formas clínicas excepto las LMO tuvieron buena evolución. Resulta fundamental enfatizar en la prevención y en el diagnóstico precoz de la enfermedad para instaurar de manera oportuna el tratamiento y evitar secuelas.

BACKGROUND: Toxocariasis is a widely spread parasitic disease. The most frequent clinical form is asymptomatic (AT) although it may present with visceral larva migrans (VLM), ocular larva migrans (OLM) or covert (TE) involvement. Aims: To describe the clinical presentation, laboratory, evolution and treatment characteristics of the cases and to compare the various clinical forms of presentation. PATIENTS AND METHODS: Retrospective analysis of all children diagnosed with toxocariasis attended at the Infectology Service of the Pedro de Elizalde Children's General Hospital between 2012-2019. RESULTS: We included 85 patients. 63.5% were males and the median age was 60 months. 49 patients presented AT, 14 VLM, 15 OLM and 7 TE. Children with LMV had lower age and higher eosinophil count. All the cases of OLM evolved with a poor visual prognosis. Treatment with albendazole was indicated in all cases of LMV, in active cases of LMO, in 4 TE and in 3 AT. CONCLUSION: This study represents one of the largest conducted in our country. The ocular forms had bad prognosis, while the visceral and covert forms had good evolution. It is essential to emphasize the prevention and early diagnosis of the disease in order to establish timely treatment and avoid sequelae.

Análise epistemológica dos conhecimentos científicos sobre Toxocara sp. com ênfase na infecção humana / Epistemological analysis of the scientific knowledge about Toxocara sp. with the emphasis on human infection

Resumo Este artigo objetivou analisar a evolução do conhecimento sobre Toxocara sp. em seu aspecto zoonótico por meio de dados científicos entre os anos de 1996 a 2015 utilizando a epistemologia como ferramenta. A análise epistemológica da evolução do conhecimento sobre o aspecto zoonótico de Toxocara sp. no Brasil demonstrou que, de uma maneira geral, foram agregadas poucas novas informações as quais tiveram, ao longo do período estudado, absorção lenta, descontínua, e não foram inseridas na realidade social do ponto de vista de Saúde Pública.

Abstract The scope of this article was to analyze the evolution of knowledge about Toxocara sp. from a zoonotic point of view by means of scientific data published between the years 1996 and 2015 using epistemology as a tool. The epistemological analysis of the evolution of knowledge on the zoonotic aspect of Toxocara sp. in Brazil revealed that, in general, little new information was added which had, over the period studied, slow and discontinuous absorption, and was not incorporated in the social reality from the standpoint of public health.

Toxocara canis en humanos, perros y suelos en ribera del Río de la Plata, provincia de Buenos Aires / Toxocara canis in humans, dogs and soil on the river side of Rio de la Plata, province of Buenos Aires / Toxocara canis em humanos, cães e solos nas margens do Rio da Prata, província de Buenos Aires

El objetivo de este trabajo fue describir la situación epidemiológica de toxocariosis en un hábitat ribereño. Se determinaron anticuerpos anti-toxocara por ELISA en sueros de 34 niños y 64 adultos, y se hallaron seroprevalencias de 32,3% y 45,3%, respectivamente. Esta fue alta en adultos y en niños de 2 a 3 años. Se realizaron 217 análisis coproparasitológicos de caninos y 23,04% fueron positivos para huevos de Toxocara canis. La distribución de caninos positivos por rango etario fue de 66% entre 1 y 6 meses; de 20,7% entre 6 y 12 meses; y de 10,3% en mayores de 12 meses. El porcentaje de animales parasitados por T. canis fue significativamente menor en relación a otros parásitos y disminuyó marcadamente con el aumento de la edad. Se analizaron 104 muestras de suelo y 1,92% de las mismas fueron positivas para huevos de T. canis. La escasa cantidad de huevos en suelos podría deberse a que los cachorros no se encontraban libres en los espacios públicos. En este barrio podría inferirse que el suelo no actuó como diseminador de esta parasitosis, sino que fueron de mayor relevancia factores como la tenencia de caninos menores de 1 año, el contacto estrecho con los mismos en ámbitos domiciliarios y las condiciones higiénico-sanitarias poco saludables.

The aim of this study was to describe the epidemiological situation of toxocariasis in a coastal habitat. Blood samples of 34 children and 64 adults were analyzed in order to determinate antibodies anti-toxocara by ELISA method. Prevalences of 32.3% and 45.3% were obtained respectively. A total of 217 coproparasitological canine analyses were performed, and 104 soil samples were analyzed. In humans, the seroprevalence of 32.4% in children and 45.3% in adults was found. In dogs, 50 samples were positive for T. canis eggs (23.04%). The distribution of canine positive for each age range yielded the following results: from 1 to 6 months, 66%; from 6 to 12 months, 20.7% and over 12 months, 10.3%. In soils, only 2 samples (1.92%) were positive for T. canis eggs. Seroloprevalence in humans was high, especially in adults and children aged 2 to 3 years. The percentage of parasitized animals by Toxocara was significantly lower in relation to other canine parasites and the percentage of dogs parasitized diminished significantly by increasing the age range. The low number of eggs found in soils could be due to the absence of puppies in public spaces. In this neighborhood, it can be inferred that the ground of public spaces did not act as a disseminator of this parasitosis, but that there were more relevant factors such as the possession of canines under 1 year of age, the close contact with them in residential areas, and unhealthy sanitary conditions.

O objetivo deste trabalho foi descrever a situação epidemiológica da toxocaríase em um habitat ripícola. Os anticorpos anti-toxocara foram determinados por ELISA em soros de 34 crianças e 64 adultos, com soroprevalência de 32,3% e 45,3%, respectivamente. Ela foi alta em adultos e em crianças de 2 a 3 anos de idade. Foram realizadas 217 análises coproparasitológicas caninas e 23,04% foram positivas para os ovos de Toxocara canis. A distribuição de caninos positivos por faixa etária foi de 66%, entre 1 e 6 meses, de 20,7%, entre 6 e 12 meses, e de 10,3% em maiores de 12 meses. A porcentagem de animais parasitados por T. canis foi significativamente menor em relação a outras parasitas e diminuiu marcadamente com o aumento da idade. Foram analisadas 104 amostras de solo e 1,92% delas foram positivas para ovos de T. canis. A escassa quantidade de ovos nos solos pode ser o resultado do fato de que os filhotes não estivessem livres nos espaços públicos. Poderia ser inferido que, nesse bairro, o solo não atuou como disseminador dessa parasitose, mas fatores como a posse de caninos menores de 1 ano de idade, um contato próximo com eles em ambientes domésticos e condições higiênico-sanitárias insalubres foram fatores de maior relevância.

Toxocariasis ocular. A propósito de un caso / Ocular toxocariasis. Case report

RESUMEN Se presentó un caso clínico de un paciente de seis años de edad, con toxocariasis ocular. La manifestación clínica fue disminución de la agudeza visual monocular. El fondo de ojo izquierdo mostró un granuloma retiniano periférico, asociado a un desgarro retiniano perilesional. El examen oftalmológico confirmó el diagnóstico de Toxocara ocular. El paciente fue tratado posteriormente mediante corticoides sistémicos y fotocoagulación láser focal en el desgarro retiniano (AU).

ABSTRACT We present the clinical case of a male patient, aged 6 years, with ocular toxocariasis. The clinical manifestation was monocular visual acuity decrease. The left ocular fundus showed a peripheral retina granuloma, associated to a perilesional retinal tear. The ophthalmological examination confirmed the diagnosis of ocular Toxocara. After that the patient was treated using systemic corticoids and focal laser coagulation in the retinal tear (AU).

Frequency of anti-Toxocara antibodies in broiler chickens in southern Brazil / Frequência de anticorpos anti-Toxocara em frangos de corte no Sul do Brasil

Abstract The aim of this study was to evaluate the presence of anti-Toxocara antibodies in naturally infected broiler chickens (n = 189) from the state of Paraná, southern Brazil. The chickens were reared in a semi-intensive system by small family farmers (n = 7). An enzyme-linked immunosorbent assay (ELISA) was performed to detect the presence of anti- Toxocara spp. IgY after serum adsorption with Ascaridia galli antigens. An overall seroprevalence of 67.7% (128/189; 95% CI = 61.1-74.4) was observed. The frequency of positive animals by farm ranged from 29.6% to 100%. The optical density and reactivity index values observed in ELISA test indicated the possible chronicity of infection of the evaluated chickens. Associations between the presence of antibodies and the area where the chickens were reared (p = 0.382) or the population density of dogs on the farm (p = 0.785) were not observed. This study shows a high prevalence of Toxocara spp. antibodies in broiler chickens reared in semi-intensive systems and provides evidence that chickens are a good indicator of environmental contamination by larva migrans agents. Further studies are necessary to assess the risk factors associated with poultry infection and the likelihood of toxocariasis transmission to humans via the ingestion of free-range chicken meat.

Resumo A finalidade do presente estudo foi avaliar a presença de anticorpos anti- Toxocara, em frangos de corte naturalmente infectados (n = 189), no Norte do Paraná, Sul do Brasil. Os frangos foram criados em sistema semi-intensivo, em pequenas propriedades rurais (n = 7). Os testes sorológicos foram realizados pela técnica de ELISA, para detecção de anticorpos IgY (IgG), com pré-adsorção do soro com antígenos de Ascaridia galli. Foi observada uma prevalência de 67,7% (128/189; IC 95% = 61,1-74,4). A frequência de animais soropositivos por propriedade variou de 29,6% a 100%. Os valores da Densidade Ótica e do Índice de Reatividade observados no teste de ELISA indicaram uma possível cronicidade de infecção dos frangos avaliados. Não foi observada correlação entre a positividade dos animais, quando comparada a área (p = 0,382) e a densidade populacional de cães por propriedade (p = 0,785). O presente estudo verificou uma alta prevalência de anticorpos anti-Toxocara em frangos de corte criados em sistema semi-intensivo e oferece dados que apontam esses animais como bons indicadores de contaminação ambiental por agentes de larva migrans . Estudos futuros são necessários para avaliar os fatores de risco associados e a possibilidade da transmissão de toxocaríase ao ser humano pela ingestão de carne de frango.

Prevalencia estimada de toxocariosis humana en la Región Lima / Estimated prevalence of human toxocariosis in Lima Region

Objetivo: Estimar la frecuencia de toxocariosis en la Región Lima. Métodos: Durante el ano 2013, se realizó una encuesta serológica no aleatorizada mediante la técnica de Elisa en pobladores de cuatro provincias de la Región Lima (Cajatambo, Canta, Huaral y Yauyos). Las muestras fueron obtenidas por personal de la DIRESA Lima, del Laboratorio de Referencia Regional en Salud Pública y procesadas en el Instituto de Medicina Tropical “Daniel A. Carrión” de la Universidad Nacional Mayor de San Marcos, Lima, Perú. Resultados: Se recolectaron 442 muestras de suero, de las cuales 142 (32,1 por ciento) fueron positivas a toxocara. El 54 por ciento de participantes fue de sexo femenino, 31 por ciento tenia entre 31 y 59 años, 45 por ciento manifestó tener un perro o un gato en su hogar. No hubo diferencias significativas entre los resultados de serolog¡a y las edades y sexos ni tenencia de canes o gatos en la población estudiada. Conclusiones: La toxocariosis es frecuente en la población de la Región Lima, por lo que es necesario realizar estudios representativos para determinar la prevalencia de esta infección.

Objective: To estimate frequency of toxocariosis in Lima Region. Methods: During 2013, a non- randomized serological survey was performed by Elisa technique in four Lima Region provinces’ (Cajatambo, Canta, Huaral and Yauyos) inhabitants. Sera samples were obtained by DIRESA Lima and Regional Reference Laboratory of Public Health workers and processed at Tropical Medicine Institute “Daniel A. Carrion” of Universidad Nacional Mayor de San Marcos, Lima, Peru. Results: From 442 sera samples obtained 142 (32.1 per cent) were positive to Toxocara; 54 per cent of participants were female, 31 per cent were between 31-59 years, 45 per cent had a dog or cat at home. There were no significant differences between serology and ages or sex or in having dog or cats. Conclusions: Toxocariosis is frequent in Lima Region inhabitants. It is necessary to perform representative studies to determine prevalence of this infection.

Aspectos epidemiológicos, diagnósticos y de tratamiento de la toxocariasis ocular / Epidemiological aspects, diagnosis, and treatment of ocular toxocariasis

Objetivo: Analizar la epidemiología, los métodos diagnósticos y los abordajes terapéuticos de la toxocariasis ocular en el Hospital de Pediatría Juan P. Garrahan. Materiales y métodos: Se realizó un estudio observacional y descriptivo en el Servicio de Oftalmología del Hospital de Pediatría J. P. Garrahan analizándose en forma retrospectiva los pacientes con ELISA positivo para IgG anti-Toxocara canis vistos en el laboratorio de Parasitología y evaluados en el servicio de Oftalmología entre enero 2006 a junio de 2013. Resultados: Se incluyeron en el estudio 301 pacientes de los cuales 95 (31,5%), presentaron diagnóstico de toxocariasis ocular (59 niños y 36 niñas) y 206 no tuvieron afección oftálmica por Toxocara canis. El 100% de los pacientes con afección ocular por el parásito presentó algún grado de alteración de la visión. Las formas de toxocariasis ocular que se registraron son: granuloma periférico aislado en 12 pacientes (12,6%), granuloma periférico con pliegue unido a papila en 36 (37,9%), granuloma de polo posterior en 7 (7,4%), endoftalmitis crónica en 3 (3,2%), neurorretinitis subaguda unilateral difusa en 2 (2,1%), desprendimiento de retina en 23 (24,2%) y en 12 (12,6%) forma indeterminada. Conclusiones: El diagnóstico de la toxocariasis ocular en la infancia tiende a hacerse en forma tardía ya que los niños pequeños no suelen manifestar a los padres la disminución visual de un ojo siendo el motivo de consulta más frecuente el estrabismo. El diagnóstico es clínico. La forma oftalmoscópica de presentación más frecuente en nuestro estudio fue el granuloma periférico con pliegue falciforme unido a papila. Oftalmoscopicamente la toxocariasis ocular puede presentarse de formas sumamente disímiles, lo cual hace dificultoso su diagnóstico y obliga a pensar siempre en éste en un niño que presenta inflamación intraocular unilateral. El uso de antiparasitarios en nuestros pacientes fue irregular (AU)

Objective: To assess the epidemiology, diagnostic methods, and treatment approach in ocular toxocariasis at the Pediatric Hospital Juan P. Garrahan. Material and methods: An observational descriptive study was conducted at the Department of Ophthalmology of the Pediatric Hospital Juan P. Garrahan. Patients with a positive ELISA for anti-Toxocara canis IgG seen at the laboratory of parasitology and evaluated at the Department of Ophthalmology between January 2006 and June 2013 were retrospectively analyzed. Results: 301 patients were included in the study of whom 95 (31.5%) had a diagnosis of ocular toxocariasis (59 boys and 36 girls) and in 206 the eyes were not affected by toxocariasis. All patients with ocular toxocariasis had some degree of visual impairment. The forms of ocular toxocariasis found were: isolated peripheral granuloma in 12 patients (12.6%), peripheral granuloma with the fold united to the papilla in 36 (37.9%), posterior pole granuloma in 7 (7.4%), chronic endophthalmitis 3 (3.2%), diffuse unilateral subacute neuroretinitis 2 (2.1%), retinal detachment in 23 (24.2%), and an indeterminate form in 12 (12.6%). Conclusions: The diagnosis of ocular toxocariasis in childhood is often late as children are not able to report vision loss to their parents. Strabism is the most common reason for consult. The diagnosis is clinical. The most frequent ophthalmoscopic presentation was peripheral granuloma with a falciform fold attached to the papilla. Ophthalmoscopically, ocular toxocariasis may present heterogeneously, resulting in a difficult diagnosis. The disease should always be suspected in a child with unilateral intraocular inflammation. The use of antiparasitic agents was variable in our patients (AU)

Seropositivity for ascariosis and toxocariosis nd cytokine expression among the indigenous people in the Venezuelan delta region / Seropositividad para ascariosis y toxocariosis y expresión de citocinas entre la población indígena de la región del delta Venezolano

The present study aimed at measuring seropositivities for infection by Ascaris suum and Toxocara canis using the excretory/secretory (E/S) antigens from Ascaris suum (AES) and Toxocara canis (TES) within an indigenous population. In addition, quantification of cytokine expressions in peripheral blood cells was determined. A total of 50 Warao indigenous were included; of which 43 were adults and seven children. In adults, 44.1% were seropositive for both parasites; whereas children had only seropositivity to one or the other helminth. For ascariosis, the percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%, respectively. While that for toxocariosis, the percentage of TES seropositivity in adults and children was low; 9.3% and 14.3%, respectively. The percentage of seronegativity was comparable for AES and TES antigens in adults (27.9%) and children (28.6%). When positive sera were analyzed by Western blotting technique using AES antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9, 98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that Blastocystis hominis, Hymenolepis nana and Entamoeba coli were the most commonly observed intestinal parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and IL-4 expressions showed that there was only a significant increased expression of IL-4 in indigenous with TES seropositivity (p < 0.002). Ascaris and Toxocara seropositivity was prevalent among Warao indigenous.

El objetivo del presente estudio fue determinar la seropositividad de infección por Ascaris suum y Toxocara canis, utilizando antígenos de excreción/secreción (E/S) de Ascaris suum (AES) y Toxocara canis (TES) en una población indígena. Adicionalmente, se cuantificó la expresión de citocinas a partir de células de sangre periférica. Un total de 50 indígenas Warao se incluyeron en el estudio; 43 fueron adultos y 7 niños. Entre los adultos, 44,1% fueron seropositivos para ambos parásitos; mientras que los niños sólo mostraron seropositividad a uno u otro de los helmintos. Para ascariosis, el porcentaje de seropositividad para los antígenos AES fue alto tanto en adultos como en niños; 23,3% y 57,1%, respectivamente. Para toxocariosis, el porcentaje de seropositividad para los antígenos TES fue bajo en adultos así como en niños; 9,3% y 14,3%, respectivamente. El porcentaje de seronegatividad fue similar tanto para los antígenos AES como para TES en adultos (27,9%) y niños (28,6%). Cuando la seropositividad fue analizada a través de la técnica de Western blotting utilizando los antígenos AES; 3 bandas de 97,2, 193,6 y 200,2 kDas fueron principalmente reconocidas. Para los antígenos TES, 9 bandas fueron mayormente identificadas; 47,4, 52,2, 84,9, 98,2, 119,1, 131,3, 175,6, 184,4 y 193,6 kDas. Los análisis coproparasitológicos mostraron que los parásitos Blastocystis hominis, Hymenolepis nana y Entamoeba coli fueron los parásitos intestinales más comúnmente observados. La cuantificación de la expresión de las citocinas IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 e IL-4 mostró que hubo un significante incremento de la expresión de IL-4 entre los indígenas con seropositividad para los antígenos TES (p < 0.002). La seropositividad para Ascaris y Toxocara fue prevalente entre los indígenas Warao.

Prevalence and Associated Risk Factors of Toxocara vitulorum Infections in Buffalo and Cattle Calves in Three Provinces of Central Cambodia

The prevalence and associated risk factors of Toxocara vitulorum infection in buffalo and cattle calves was studied in 3 provinces in central Cambodia. Fecal samples were collected from 517 calves between the age of 1-15 weeks and processed for nematode egg counts by a modified McMaster method. A total of 64 calves were found to excrete T. vitulorum eggs in their feces (12.4%; 95% exact CI: 9.7-15.5). The mean fecal egg count was 2,798 EPG (SD=16,351; range=0-224,400). A multivariable generalized linear mixed model showed higher odds of T. vitulorum infection for buffalo versus cattle, for animals aged 4-8 weeks versus younger and older ones, and for animals with strongyle infection. There was no association with fecal consistency. Farmers should be aware of the potential impact of T. vitulorum, and treat their calves at the age of 2-3 weeks with anthelmintics such as benzimidazoles or pyrantel.

Toxocariasis: seroprevalence in abandoned-institutionalized children and infants / Toxocariosis: seroprevalencia en infantes expósitos, abandonados e institucionalizados

Toxocariasis is an infection that has worldwide distribution. Toxocara canis is the most relevant agent due to its frequent occurrence in humans. Soil contamination with embryonated eggs is the primary source of T. canis. This study aimed to determine the seroprevalence of toxocariasis in 10-month to 3 year-old abandoned infants, considered to be at high risk because of their orphanhood status and early age. Blood samples were collected from 120 children institutionalized in an orphanage in the city of La Plata. In this study, we observed 38.33% of seropositive cases for T. canis by ELISA and 45% by Western blot techniques; significant differences among groups A (<1 year), B (1-2 years) and C (>2 years) were also found. In research group A, children presented a seropositivity rate of 23.91%, in group B of 42.85% and in group C of 56%, which indicates an increase in frequency as age advances, probably because of greater chances of contact with infective forms of the parasite since canines and soil are frequently infected with T. canis eggs. Abandoned children come from poor households, under highly unsanitary conditions resulting from inadequate or lack of water supply and sewer networks, and frequent promiscuity with canines, which promotes the occurrence of parasitic diseases. These children are highly vulnerable due to their orphanhood status and age.

La toxocariosis es una enfermedad presente en todo el mundo. Como causa primaria de infección se cita la contaminación de los suelos con huevos embrionados de Toxocara canis. Nuestro objetivo fue determinar la seroprevalencia de toxocariosis en niños expósitos (abandonados) de 10 meses hasta 3 años, los que se consideran de alto riesgo por su condición de orfandad y escasa edad. Las muestras de sangre fueron recolectadas de 120 niños institucionalizados en un orfelinato de la ciudad de La Plata. En este estudio, se observó un porcentaje de seropositivos para T. canis de 38,33 % por la técnica de ELISA y de 45 % por la técnica de Western blot, con diferencias significativas entre los grupos etarios estudiados (A: < 1 año, B: 1-2 años, C: > 2 años). Los niños del grupo A presentaron una frecuencia de seropositividad de 23,91 %; los del grupo B, de 42,85 % y en los niños del grupo C fue del 56 %. Esto indica un incremento de la frecuencia de presentación a medida que aumentó la edad, debido probablemente a las mayores posibilidades de contactar con estados infectantes del parásito, ya que los caninos y el suelo se hallan frecuentemente infectados por huevos de T. canis. Los niños abandonados provienen de hogares carenciados, donde a las malas condiciones de higiene resultantes de la ausencia de red de agua y cloacal se le agrega la frecuente promiscuidad con caninos, lo cual propicia la presencia de parasitosis. Sumado a la condición de desamparo, esto produce un estado de máxima vulnerabilidad.

Toxocariasis in children attending a Public Health Service Pneumology Unit in Paraná State, Brazil / Toxocaríase em crianças atendidas em Unidade de Pneumologia do Serviço de Saúde Pública, Paraná, Brasil

The enzyme-linked immunosorbent assay (ELISA) is the most widely used tool to detect anti-Toxocara IgG antibodies for both serodiagnostic and seroepidemiological surveys on human toxocariasis. In the last eight years a high prevalence of toxocariasis (32.2-56.0%) has been reported in children attending public health units from municipalities in the state of Paraná, Brazil. Therefore, the aim of this work was to compare the frequency found among the general child population with that of children attending a public pneumology service in Maringá, Paraná, Brazil and describe the laboratorial, clinical and epidemiological findings. The research was conducted at the Consórcio Público Intermunicipal de Saúde do Setentrião Paranaense (CISAMUSEP) from July 2009 to July 2010 among children aged between one and 15 years. From a total of 167 children studied, only 4.2% (7/167) tested positive for anti-Toxocara spp. IgG antibodies and presented mild eosinophilia (2/7), increased serum IgE levels (6/7) and a positive allergy test for mites (5/7). The presence of pets (dogs or cats) at home did not correlate with the seroprevalence. In conclusion, cases of toxocariasis involving the respiratory tract are rare in children attending a public health pneumology unit in the northwestern region of Paraná State, despite the high prevalence of this type of toxocariasis among the infantile population attending Basic Health Units in the same geographical area.

O teste imunoenzimático (ELISA) constitui a ferramenta mais utilizada no diagnóstico individual da toxocaríase humana e/ou em inquéritos soroepidemiológicos para pesquisa de anticorpos IgG anti-Toxocara spp. Tendo em vista a elevada freqüência da toxocaríase (32,2% e 56,0%) observada em crianças atendidas em Unidades Básicas de Saúde de municípios do noroeste do Paraná, durante pesquisas realizadas ao longo dos últimos oito anos, o objetivo deste trabalho foi comparar estas frequências em crianças encaminhadas a uma unidade de Pneumologia do serviço de saúde pública da cidade de Maringá, noroeste do Estado do Paraná, Brasil e descrever os achados laboratoriais, clínicos e epidemiológicos das crianças soropositivas. A pesquisa foi realizada no Centro de Especialidades Regional - CISAMUSEP - entre julho de 2009 a julho de 2010, em crianças com idade entre um e 15 anos. De 167 crianças investigadas, sete (4,2%) apresentaram anticorpos IgG anti-Toxocara spp. Entre elas, duas (1,2%) crianças soropositivas apresentaram eosinofilia (baixos níveis), seis mostraram níveis elevados de IgE e cinco, teste alérgico positivo, principalmente para ácaros. Concluindo, no noroeste do estado do Paraná foram observados raros casos de crianças com toxocaríase envolvendo o trato respiratório e que foram atendidas por serviços públicos de Pneumologia ainda que na região estudada tenha sido observada elevada prevalência de toxocaríase em crianças assistidas pelas Unidades Básicas de Saúde (BHU).

Prevalencia de helmintos intestinales en gatos domésticos del departamento del Quindío, Colombia / Prevalence of intestinal helminths in cats in Quindío, Colombia

Introducción. Las enfermedades producidas por helmintos están ampliamente distribuidas en el mundo y muchas de ellas se consideran zoonosis. Los animales de compañía cumplen un papel trascendental en la transmisión a los humanos. Objetivo. Determinar la prevalencia de helmintos intestinales en gatos del departamento del Quindío. Materiales y métodos. Se estudiaron 121 gatos domésticos del departamento del Quindío, de los cuales se registraron los datos de sexo, edad y condición corporal. Se recolectaron heces y se procesaron mediante las técnicas de Ritchie modificada y de Kato-Katz. Resultados. De los 121 gatos, 42,14 % (IC95%: 33,35-50,94) y 45,45 % (IC95%: 36,58-54,32) resultaron parasitados con alguna especie de helminto adulto según la presencia de huevos en sus heces, mediante las técnicas de Ritchie y de Kato-Katz, respectivamente. Toxocara cati fue el parásito más prevalente(Ritchie: 37,2 %; Kato-Katz: 43 %), seguido por Ancylostoma spp. (Ritchie: 7,43 %; Kato-Katz: 5,78 %) y Aelurostrongylus abstrusus (Ritchie: 0,82 %). Sesenta y cinco (53,71 %) gatos eran hembras y 56 (46,28 %) eran machos; la prevalencia de infección fue similar en ambos sexos. Los felinos mayores de 4 años de edad presentaron mayor prevalencia de parásitos (81,8 %), seguidos por los de 1 a 4 años (48,8 %) y, por último, por los menores de un año (28,6 %). Se encontró una buena condición corporal en 77,68 % y este grupo presentó menor frecuencia de helmintos intestinales. Conclusión. La prevalencia de helmintos intestinales en gatos domésticos del departamento del Quindío fue de 43,8 %, lo que hace necesario establecer programas de vigilancia y prevención en la población humana y felina.

Introduction. Diseases caused by helminths are widely distributed in the world and many of them are considered zoonoses in which pets play a major role in transmission to humans. Objective. The prevalence of intestinal helminths was determined in cats in Quindío Province. Materials and methods. One hundred twenty-one cats were characterized --data recorded included sex, age and body condition. Fecal samples were collected and processed using the modified Ritchie and modified Kato-Katz techniques to determine the presence of intestinal helminths. Results. Of the 121 cats, 42.1%, (95% CI: 33.4-50.9) and 45.5% (95% CI: 36.6-54.3) were parasitized with at least one adult helminth species as evidenced by the presence of eggs in their fecal samples. Toxocara cati was the most prevalent parasite (Ritchie: 37.2%, Kato-Katz: 43%), followed by Ancylostoma spp. (Ritchie: 7.4%, Kato-Katz: 5.8%) and Aelurostrongylus abstrusus (Ritchie: 0.82%). Sixty-five cats (53.7%) were females and 56 (46.3%) males; the prevalence of infection was similar in both sexes. Cats older than 4 years had the highest prevalence (81.8%) followed by those aged 1 to 4 years (48.8%) and by those under 1 year (28.6%). The majority of cats, 77.7%, were found to be in good body condition and this group had the lowest frequency of intestinal helminths with both techniques. Conclusion. The prevalence of intestinal helminths in domestic cats in Quindío was 43.8%; it is necessary to establish surveillance and prevention programs in the human and feline populations.

An evaluation of the dot-ELISA procedure as a diagnostic test in an area with a high prevalence of human Toxocara canis infection

The aim of this work was to evaluate a dot-enzyme-linked immunosorbent assay (dot-ELISA) using excretory-secretory antigens from the larval stages of Toxocara canis for the diagnosis of toxocariasis. A secondary aim was to establish the optimal conditions for its use in an area with a high prevalence of human T. canis infection. The dot-ELISA test was standardised using different concentrations of the antigen fixed on nitrocellulose paper strips and increasing dilutions of the serum and conjugate. Both the dot-ELISA and standard ELISA methods were tested in parallel with the same batch of sera from controls and from individuals living in the problem area. The best results were obtained with 1.33 µg/mL of antigen, dilutions of 1/80 for the samples and controls and a dilution of 1/5,000 for the anti-human IgG-peroxidase conjugate. All steps of the procedure were performed at room temperature. The coincidence between ELISA and dot-ELISA was 85 percent and the kappa index was 0.72. The dot-ELISA test described here is rapid, easy to perform and does not require expensive equipment. Thus, this test is suitable for the serological diagnosis of human T. canis infection in field surveys and in the primary health care centres of endemic regions.

A Seroepidemiological Survey of Toxocariasis among Eosinophilia Patients in Chungcheongnam-do

There have been several reports on the relationship between toxocariasis and eosinophilia, but all have been limited to the areas of Seoul or Gangwon-do. In the present study, we investigated the seroprevalence of toxocariasis among eosinophilia patients in Chungcheongnam-do, the central district of Korea. Among the 101 patients tested, 51 (50.5%) were identified as positive by Toxocara ELISA, and 46 (45.5%) were confidently diagnosed with toxocariasis because of absence of any other cause of eosinophilia. Whereas 22 of 42 seropositive patients (52.3%) had a recent history of consuming raw livers, especially the cow liver, only 1 of 25 seronegative patients (4%) had done so (P<0.01). From these results, we could confirm that toxocariasis is related to eosinophilia, and infer that ingestion of raw cow liver plays a vital role in the transmission of toxocariasis in Chungcheongnam-do.

Toxocariosis humana en el Perú: aspectos epidemiológicos, clínicos y de laboratorio / Human toxocariasis: epidemiology, clinical and laboratory aspects

Toxocariosis es una infección causada por larvas de nemátodos del género Toxocara siendo T. canis o Toxocara cati, nemátodos del perro y gato respectivamente, los más importantes para el ser humano. Las especies del Género Toxocara pertenecen a la orden Ascaridida, superfamilia Ascaridiodea, familia Toxocaridae. La enfermedad es ocasionada principalmente por T. canis. La toxocariosis humana fue descrita por primera vez por Wilder en 1950, quien identificó un nemátodo de especie desconocida en un granuloma de retina de un niño. En 1952, Beaver reportó casos de una enfermedad multisistémica, crónica y severa, asociada a hipereosinofilia . En el Perú, en 1991, Maguiña y col reportaron los primeros casos de Larva migrans visceral y en 1999, Miranda y col, reportaron los primeros casos de Larva migrans ocular.

Toxocariasis is an infection caused by nematode larvae from Toxocara genus, and the most important infective agents for humans are Toxocara canis and Toxocara cati, parasites from dogs and cats, respectively. Toxocara species belong to Ascaridida order, Ascaridodea super-family, Toxocaridae family. The disease in humans is mainly caused by T. canis. Human toxocariasis was described for the .rst time by Wilder in 1950, who identi.ed a then-unknown nematode in a child presenting with a granulomatous lesion in one of his eyes. In 1952, Beaver reported cases of a multi-systemic, chronic, and sever disease, associated to hypereosinophilia. In Peru, in 1991, Maguiña et al. reported the very. rst cases of visceral larva migrans, and in 1999, Miranda et al. reported the very .rst cases of ocular larva migrans.

Detección de lesiones oculares en niños seropositivos para Toxocara canis / Prevalence of ocular lesions in children seropositive to Toxocara canis

Intraocular invasion by Toxocara canis is one of the most commonly recognized etiologies of uveitis and blindness in children. In order to estimate the prevalence of ocular lesions caused by toxocariasis in a pediatric referral hospital, we conducted a retrospective analysis of clinical charts of all children seropositive to Toxocara canis, who also had an eye exam between the years 2005 and 2009 at the Calvo Mackenna Children's Hospital in Santiago, Chile. We identified 175 children [mean age 6 years (range 0.66-15)] seropositive to Toxocara canis, who had dilated eye exam. Only one child [(0.57 percent); 95 percent CI, -0.55 - 1.69] had ophthalmoscopic findings compatible with Toxocara canis infection. The patient also suffered from decreased vision of the affected eye. The information gained from this study may be of useful for the implementation of algorithms for the ophthalmological examination of children seropositive to Toxocara canis in public hospitals in Chile.

La invasión intraocular por el nematodo Toxocara canis constituye una de las causas más frecuentes de uveitis en los niños, pudiendo conducir a la ceguera. Para conocer la prevalencia de lesiones oculares en niños con serología positiva para este parásito en un hospital pediátrico de referencia, realizamos un estudio retrospectivo de las fichas clínicas de los pacientes referidos para examen oftalmológico en el Hospital Luis Calvo Mackenna entre los años 2005 y 2009. Encontramos 175 niños con serología positiva y examen oftalmológico, cuya edad promedio al momento del examen fue de 6 años (rango 0,66-15). En sólo un niño [(0,57 por ciento); 95 por ciento IC, -0,55-1,69] se encontraron lesiones oculares atribuibles a T. canis. El paciente presentaba además disminución de visión. La información obtenida en este estudio podría ser de utilidad en el diseño de un algoritmo para el examen oftalmológico de niños seropositivos a T. canis en el ambiente hospitalario en Chile.

Prevalência e fatores de risco da infecção humana por Toxocara canis em Salvador, Estado da Bahia / Prevalence and risk factors of human infection by Toxocara canis in Salvador, State of Bahia, Brazil

INTRODUÇÃO: Larva migrans visceral é causada por Toxocara sp e nunca foi estudada na Bahia. Neste trabalho, investigou-se a prevalência e fatores de risco de infecção por Toxocara canis, em indivíduos de Salvador. MÉTODOS: Trezentos e trinta e oito indivíduos foram investigados para presença de anticorpos IgG séricos anti-T. canis. RESULTADOS: IgG anti-T. canis foi mais alta em indivíduos de classe social baixa com maior contato com cães e gatos, indicando que estas variáveis são fatores de risco para esta infecção. CONCLUSÕES: A prevalência de infecção por T. canis foi alta. Os fatores de risco desta infecção encontrados estão de acordo com a literatura.

INTRODUCTION: Larva migrans visceral is caused by Toxocara sp and has never been studied in Bahia. This work investigated the prevalence and risk factors for infection by Toxocara canis in individuals from Salvador, State of Bahia. METHODS: Three hundred and thirty-eight individuals were investigated for the presence of serum IgG anti-T. canis. RESULTS: IgG anti-T. canis was higher in individuals from lower social classes who had more contact with dogs and cats, indicating that these variables are factors risk for this infection. CONCLUSIONS: The prevalence of T. canis infection was high. The risk factors for this infection identified are in agreement with in the literature.

Anti-Toxocara antibodies detected in children attending elementary school in Vitoria, State of Espírito Santo, Brazil: prevalence and associated factors / Anticorpos anti-Toxocara em crianças admitidas na escola fundamental em Vitória, Estado do Espírito Santo: prevalência e fatores associados

INTRODUCTION: The aim of this study was to evaluate the frequency of anti-Toxocara antibodies in serum from 7-year-old children attending elementary school in Vitória-ES, Brazil and to correlate these antibodies with socio-demographic factors, the presence of intestinal helminths, blood eosinophil numbers, past history of allergy or asthma, and clinical manifestations of helminth infections. METHODS: The detection of anti-Toxocara antibodies was performed using an ELISA (Cellabs Pty Ltd)on serum from 391 children who had already been examined by fecal examination and blood cell counts. Data from clinical and physical examinations were obtained for all children. RESULTS: The prevalence of anti-Toxocara antibodies was 51.6%, with no gender differences. No significant differences were observed between positive serology and the presence or absence of intestinal worms (60.3 and 51.7%, respectively; p = 0.286). The only variables significantly related to positive serology were onycophagy and the use of unfiltered water. Although eosinophilia (blood eosinophil count higher than 600/mm³) was significantly related to the presence of a positive ELISA result, this significance disappeared when we considered only children without worms or without a past history of allergy or asthma. No clinical symptoms related to Toxocara infection were observed. CONCLUSIONS: There is a high prevalence of anti-Toxocara antibodies in children attending elementary schools in Vitória, which may be partially related to cross-reactivity with intestinal helminths or to a high frequency of infection with a small number of Toxocara eggs.

INTRODUÇÃO: O objetivo desse estudo foi avaliar a prevalência de anticorpos anti-Toxocara em crianças admitidas no primeiro ano de escola fundamental em Vitória e correlacionar com variáveis sociodemográficas, helmintos intestinais, eosinófilos no sangue, geofagia, onicofagia, história de asma e alergia cutânea e manifestações clínicas. MÉTODOS: A pesquisa de anticorpos anti-Toxocara, utilizando um teste de ELISA (Cellabs), foi realizada em 391 crianças nas quais foram realizados exames parasitológicos de fezes e hemograma completo. Todas as crianças foram submetidas a exame clínico e físico. RESULTADOS: A prevalência de reação positiva foi de 51,6%, sem diferença entre os sexos. Não foram observadas diferenças significativas na prevalência de reação positiva em crianças com ou sem helmintos intestinais (60,3 e 51,7%, respectivamente; p = 0.286). Ainda que a frequência de eosinófilos acima de 600/mm³ tenha sido significativamente maior em crianças com sorologia positiva, a significância desapareceu quando se considerou as crianças sem helmintos intestinais ou história pregressa de asma ou alergia cutânea. As únicas variáveis significativamente correlacionadas, de modo independente, com a presença de sorologia positiva foram onicofagia e hábito de beber água não filtrada. Nenhuma criança apresentou manifestação clínica relacionada com a presença de anticorpos anti-Toxocara. CONCLUSÕES: A prevalência de anticorpos anti-Toxocara em crianças admitidas nas escolas elementares em Vitória é alta, a qual pode estar, em parte, relacionada à reação cruzada com antígenos de helmintos intestinais ou devida a frequente exposição a baixas quantidades de ovos do Toxocara.

Protective and risk factors for toxocariasis in children from two different social classes of Brazil / Fatores de risco e protetores para toxocaríase em crianças de duas diferentes classes socioeconômicas do Brasil

The aim of this study was to analyze the prevalence of Toxocara spp. antibodies in children from two different socioeconomic classes in the Presidente Prudente municipality, São Paulo State, Brazil, and the protective and risk factors associated with toxocariasis. One hundred and twenty-six middle-class (MC) and 126 disadvantaged children (DC) were included in this study. Anti-Toxocara ELISA test was performed in order to evaluate seroprevalence. A survey was applied to the children's guardians/parents in order to analyze the protective and risk factors. The overall prevalence was 11.1 percent, and of 9.5 percent (12/126) and 12.7 percent (16/126) for MC and DC subgroups, respectively. Toxocara seropositivity was inversely proportional to the family income. A high household income was considered a protective factor for toxocariasis in the total population and in both MC and DC subgroups. Being a girl was considered a protective factor for the total population and for both subgroups. Whilst being an owner of cat was a risk factor for children belonging to the total and for both MC and DC subgroups, having dog was considered as a risk factor for only the MC. Epidemiologic protective/factor risks can be distinct depending on the strata of the same population. Thus, it is relevant to evaluate these factors independently for different socioeconomic classes in order to design future investigations and programs for preventing the infection of human beings by Toxocara spp. and other geohelminths.

A finalidade do presente estudo foi avaliar a prevalência de anticorpos anti-Toxocara spp. em crianças de duas diferentes classes sociais do município de Presidente Prudente, São Paulo, Brasil, e os fatores protetores e de risco associados à toxocaríase. Foram incluídas no estudo 126 crianças de classe média (CM) e 126 de baixa renda (BR). O teste ELISA foi realizado para avaliar a seroprevalência. Um questionário foi aplicado aos pais ou responsáveis pelas crianças para análise dos fatores protetores e de risco. A prevalência na população foi de 11,1 por cento, sendo de 9,5 por cento (12/126) e 12,7 por cento (16/127) para os subgrupos CM e BR. A seropositividade foi inversamente proporcional à renda familiar. Observou-se que uma alta renda familiar foi considerado um fator de proteção tanto para a população total como para ambos os subgrupos CM e BR. Da mesma forma, ser criança do sexo feminino foi outro fator de proteção para a população total e para os dois subgrupos. Possuir gato foi um fator de risco para a população total e para os dois subgrupos estudados, enquanto que possuir cão foi considerado como fator de risco apenas para as crianças de classe média. Os fatores protetores e de risco podem ser diferentes em uma mesma população a depender do estrato social. Dessa forma, é relevante avaliar esses fatores independentemente para diferentes classes sócio-econômicas para elaboração de futuros estudos e programas de prevenção à infecção humana por Toxocara spp. e outros geohelmintos.