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)

Gastrointestinal parasites in goats from Monte Castelo, Santa Catarina, Brazil / Parasitas gastrintestinais em caprinos de Monte Castelo, Santa Catarina, Brasil

This study was carried out with the aim of estimating the degree of gastrointestinal helminth infection in goats on the Northern Plateau of Santa Catarina. Twelve young females and 11 adult females were used. Every 28 days, feces samples were taken to quantify the nematode eggs per gram of feces (EPG). Larval culturing was performed on a pool of positive samples from the same group. The fecal egg counts (FECs) ranged from zero to 10,400 EPG in the young group and zero to 7,600 EPG in the adult group. The mean FECs were between 583.3 and 4441.7 in the young group and between 418.2 and 2181.8 in the adult group. Eggs of the order Strongylida and genera Moniezia and Toxocara, and oocysts of Coccidia, were observed. The young animals were more affected and Haemonchus was the most prevalent genus in the samples.

Este trabalho foi realizado com o objetivo de estimar o grau de infecção dos helmintos gastrintestinais em um rebanho caprino criado no Planalto Norte Catarinense. Foram utilizadas 12 fêmeas jovens e 11 adultas, das quais, a cada 28 dias, foram coletadas amostras de fezes diretamente do reto, totalizando 12 coletas, para quantificação de ovos por grama de fezes (OPG) e cultivo de larvas através de "pool" das amostras positivas do mesmo grupo. A contagem de OPG variou de zero a 10.400 nos animais jovens e de zero a 7.600 nos adultos. As médias do OPG entre as coletas foram de 583,3 a 4.441,7 no grupo jovem e de 418,2 a 2.181,8 nos adultos, sendo observados ovos da ordem Strongylida, dos gêneros Moniezia e Toxocara, bem como oocistos de coccídeos. Os animais mais jovens foram os mais acometidos, sendo o gênero Haemonchus o mais prevalente.

Seroepidemiología de la toxocariasis en una comunidad indígena Yucpa de la Sierra de Perijá al occidente de Venezuela / Seroepidemilogy of toxocariasis in a Yucpa amerindian community from the Perijá Mountains, western Venezuela

El propósito de este estudio fue determinar la seroprevalencia de infección por Toxocara spp en una comunidad indígena de la sierra de Perijá, al occidente de Venezuela, identificando el efecto de los cambios socioculturales sobre los factores de riesgo. Se estudió el 75,4% del total de la comunidad (110 individuos). La determinación de anticuerpos anti-Toxocara spp se realizó a través de una técnica de ELISA comercial. El análisis estadístico se realizó a través de la prueba de Chi cuadrado y la correlación de Spearman. El porcentaje general de infección fue de 21,7%, la más alta prevalencia se observó en el grupo de mayores de 50 años (37,5%). No se apreciaron diferencias estadísticamente significativas con relación al sexo. La prevalencia encontrada fue más alta que la apreciada en poblaciones urbanas y más baja que en otras comunidades indígenas. El proceso de transculturización en esta comunidad indígena es un factor de riesgo para la infección por Toxocara spp

The aim of this study was to determine the Toxocara spp infection seroprevalence in an Amerindian community from western Venezuela, identifying the effect of socio-cultural changes on the risk factors. 75.4% of the community, 110 individuals, were studied. Blood samples were gathered by venous puncture. Determination of anti-Toxocara spp antibodies was carried out using a commercial ELISA technique. The overall prevalence was 21.7%. Higher prevalence was observed in the age group >50 years old (37.5%). There were no statistically significant differences with regard to sex. The prevalence found was higher than that of an urban population and lower than in other indigenous communities. The transculturization process in this indigenous community is a risk factor for Toxocara spp infection

Longevity of Toxocara cati Larvae and Pathology in Tissues of Experimentally Infected Chickens

This study was conducted to determine the distribution patterns and duration of stay of Toxocara cati larvae in organs of chickens and to investigate chronic phase and potential zoonotic risk of toxocariasis in chickens. Chickens were orally infected with 1,000 embryonated T. cati eggs and necropsied 240 days post-infection. Organs of the chickens were examined at gross and microscopic levels; tissues were digested to recover larvae. Peribronchiolitis with infiltration of lymphocytes, and hyperplasia of bronchiolar associated lymphatic tissues (BALT) and goblet cells, were evident in the lungs of infected chickens. There were mild hemorrhages and infiltration of lymphocytes and a few eosinophils in the meninges. Larvae were recovered from 30% of the exposed chickens. Larvae recovery indicated that T. cati larvae stay alive for at least 240 days in the chicken brain. Therefore, chickens may potentially act as a paratenic host in nature and transfer T. cati larvae to other hosts.

Experimental Toxocara cati Infection in Gerbils and Rats

Mongolian gerbils and Wistar rats were inoculated orally with 240 and 2,500 Toxocara cati embryonated eggs, respectively, to evaluate the larval recovery in different tissues and organs, such as the liver, lungs, heart, kidney, and skeletal muscles after 5, 30, 49, 70, and 92 days post-infection (PI). Larval recovery rates were 1.7-30.0% in Mongolian gerbils on days 5-92 PI and 0.2-3.8% in rats on the same days. These results indicate that Mongolian gerbils and Wistar rats are suitable experimental paratenic hosts for the study of neurological toxocariasis as well as visceral toxocariasis.

Huevos infectivos de toxocara, en arenas de plazas y parques de Asunción, Paraguay / Toxocara ova in the sand of squares and parks of Asunción, Paraguay

Los vermes del género Toxocarapertenecen a la familia Ascaridae, siendo los agentes patógenos más importantes para el hompe T. canis y T. cati, productores de larva migrante visceral (LMV). Las larvas de Toxocara fueron identificadas por primera vez por Beaver, en 1952, en una biopsia de hígado de un niño de 2 años, acompañado por hepatomegalia y eosinofilia. El cuadro de LMV ocurre principalmente en niños de 1 a 5 años, con una historia de consumo de suelos (geofagia), contaminados con heces de caninos o felinos infectados. Los hallazgos clínicos pueden incluir marcada eosinofilia, hepatomegalia, neumonitis transitoria e hipergammaglubulinemia. Con el objeto de analizar la presencia de los huevos de estos helmintos en las plazas de la ciudad de Asunción, se tomaron muestras de suelo que contenían arena, en las cercanías de los juegos infantiles. Se sortearon aleatoriamente 51 plazas y parques, de un total de las 98 registrados en la Municipalidad de Asunción. Se halló la superficie de la zona que poseía arena, de las plazas sorteadas y se tomaron 2 muestras de 30 x 30 cm de superficie por 0,5 cm de profundidad, por cada 15 m2. Para el efecto fueron utilizados espátulas y frascos, previamente esterilizados. Se llenaron con agua los frascos y se agitaron fuertemente para obtener una buena emulsión, se filtraron las muestras y se procesaron por el método de flotación con sulfato de zinc al 33 por ciento. De los 51 sitios analizados, se encontraron huevos de Toxocara en 27 de ellos (53 por ciento). Entre los parques más concurridos que presentaron huevos de Toxocara fueron el Parque Caballero y el de Ñu guazú. La elevada prevalencia de huevos de Toxocara, encontrados en los suelos de plazas y parques públicos, indica el elevado riesgo para la salud de las personas, ya que los mismos son utilizados como áreas de recreación, especialmente por los niños, siendo ellos los que tienen más contacto con las arenas en las zonas de juego.

Contaminación ambiental por huevos de toxocara sp. en algunas plazas y parques públicos de Santiago de Chile, 1999 / Environmental contamination by toxocara sp. eggs in public squares and parks from Santiago, Chile, 1999

Most of cases of visceral larva migrans syndrome are caused by Toxocara canis larvae. Man acquires the infection by accidental ingestion of ripe eggs of the helminth. In order to find out the frequency of the presence of Toxocara sp. eggs in dog fecal specimens from public places of Santiago city in 1999 july-september a study was carried out in 84 squares and 12 parks from 32 couties. Three fecal samples were collected in each of these places, making a total of 288. Each sample was processed according to a modified Telemann method and three smears of each were microcopically examined. Toxocara sp. eggs were found in 39 (13.5 percent) fecal specimens. In 28/84 (33.3 percent) squares and in 8/12 (66.7 percent) parks these eggs were detected. These results make necessary the control of dogs and cats populations with the aim of reduce the presence of animals without responsible owners. It schould be advisable to prevent dogs and cats defecation in public areas grounds, trying to exclude these animals from recreation areas

Granuloma cerebral por toxocara sp: comunicación de un caso pediátrico / Brain granuloma produced by toxacara sp: report of a pediatric case

La toxocarosis es la infección parasitaria producida en el hombre por la migración de larvas de Toxocara sp a través de diferentes parénquimas: hígado, pulmón, sistema nervioso central (SNC) y ojo. Se presenta el caso de un escolar de 7 años con un cuadro convulsivo focal secundariamente generalizado e imagen de nódulo hipodenso en la tomografía axial computarizada. Ella vivía en una región rural y tenía estrecho contacto con perros. Recibió tratamiento antibiótico oral con cotrimoxazol, rifampicina y metronidazol durante 82 días. Por persistencia de la lesión, recurrencia de la convulsión y antecedentes epidemiológicos, se realizó estudio serológico para toxocarosis (test de ELISA IgG), que fue positivo en dilución de 1:512. Se trató con albendazol por 21 días y posteriormente se controló con resonancia magnética cerebral que fue normal, la serología se negativizó y las convulsiones no se repitieron. El compromiso de SNC por Toxocara sp puede producir encefelitis, mielitis, meningitis eosinofílica, granuloma cerebral, encefalopatía estática, alteraciones motoras y psiquiátricas. Es fundamental la educación sobre las medidas de prevención

Asma y toxocarosis encubierta / Asthma and covert toxocariasis

Se estudió la relación entre asma bronquial y toxocarosis encubierta. Se seleccionaron 38 pacientes con síndrome de asma bronquial. Se estabelecieron criterios de inclusión/exclusión. Como población control se evaluaron 44 pacientes sin asma con los mismos criterios. Los anticuerpos antitoxocara de tipo IgG e IgE se detectaron mediante enzimoinmunoanálisis (ELISA). Las pruebas cutáneas se realizaron mediante inyección de alergenos habituales y de material excretor/secretor de Toxocara canis obtenido por cultivo in vitro de larvas en estadio II (Ag E/S). Dentro de la población con asma resultó serológicamente positiva el 68.42 por ciento, diferenciándose significativamente de la población control (13.63 por ciento). El porcentaje de pacientes asmáticos con ambos marcadores antitoxocara positivos fue 26.31 por ciento. En la población control fue 4.54 por ciento. El 100 por ciento de los pacientes con asma y seropositividad para IgE antitoxocara dieron reactividad cutánea para el Ag E/S de T. canis. Se concluye que el grupo de pacientes con asma bronquial presentó una indudable asociación con los marcadores serológicos antitoxocara IgE e IgG positivos y con la reactvidad cutánea al Ag E/S, por lo que podría inferirse que cursan una toxocarosis encubierta.

Verduras de consumo humano como probable fuente de infección de toxocara sp. para el hombre / Vegetables for human consumption as probable source of toxocara sp. infection to man

Although Toxocara canis life cycle is known, other possible mechanisms dynamically involved in its transmission to man are still ignored. The object of the present investigation was to search the occurrence of Toxocara sp. eggs in vegetables which humans consume. Five hundred and thirty six vegetables from a supply distribution center in Mexico City (Distrito Federal) were examined. Those included 212 carrots, 76 potatoes, 31 radishes, 22 mushrooms, 27 lettuces, 20 sweet potatoes and 66 bundles of spinaches, 32 bundles of salt-worts, 29 bundles of coriander, and 21 bundles of purslane. Each unit or bundle was @ashed with 50 ml of sterilized water, allowing sedimentation at room temperatura for 8 hours. Five ml of sediment were centrifugated at 3,000 r.p.m. for 5 minutes. Sediment was examined in lugol stained fresh plates through light microscopy, which tumed to be Toxocara sp. eggs were found only in two vegetables: 1.9 percent of car-rots and 6.5 percent of radishes. Toxocara sp. eggs were: 66.7 percent recently emitted and 33.3 percent embryonated. Other parasite elements were: Ascaris lumbricoides eggs 1.9 percent in carrots, 2.6 percent in potatoes, 9. 1 percent in mushrooms, 6.9 percent in corianders, 20.0 percent in sweet potatoes and 6. 1 percent in spinachs. Entamoeba histolytica cyts were found in 0.9 percent of carrots. Soil contamination with Toxocara sp. eggs from parasitized dogs or cats, or with either sewage systems or contaminated water where vegetables for human consumption are grown, play a role as a transmission mechanism must be deeperly studied since 33.3 percent of Toxocara sp. eggs found contained larvae, potentially infective to man

Frecuencia de hallazgo de huevos de toxocara cati en gatos domésticos de Ciudad de México y del estado de México / Frequency of toxocara cati eggs in domestic cats at Mexico City and at Mexico State

Toxocariosis is a zoonosis which has beem widely studied in dogs. However, not much is known about this parasitosis in cats. The aim of the present work was to determine the frequency of Toxocara cati in domestic cats in Mexico City and the State of Mexico. Feces of 660 domestic cats were studied by the Faust concentration-floating test; 401 samples were from cats living in Mexico City of which 308 lived in houses and 93 in apartments; 231 were from urban areas of the State of Mexico an 28 from a rural area of the same state. The total frequency of T. cati eggs obtained from domestic cats in Mexico City was 42.9 percent; in cats living in apartments it was 18.3 percent and in cats living in houses it was 50.3 percent. In domestic cats from the State of Mexico, T. cati frequency was 36.4 percent in the urban and 21.4 percent in the rural areas. We consider that toxocariosis frequency observed at the two studied sites is high and that the need to prevent dissemination of the infectious forms of T. cati is urgent,as it the necessity of informing the population of the risk of living with T. cati parasited animals and of the anatomopathological alterations caused by T. cati in man

potential risk of contracting Toxocariasis in heliopolis district, Cairo, Egypt

Out of 600 soil samples collected from 3 sport clubs and 3 public parks within Heliopolis District, 182 samples contained Toxocara species eggs, with an overall prevalence rate of 30.3%. Public parks especially children's sand boxes had the highest percentage of the recovered eggs. Prevalence did not vary greatly from winter to summer, though more viable eggs were noticed in the samples collected in winter. The findings demonstrated the potential risk of contracting toxocariasis [VLM] by children playing in the sand boxes of the investigated areas

effects of toxocara canis infection on ethnologically assessed fighting generated by breeding activity in mice

The effect of infection of T.canis infective larvae were investigated on social [intermale] aggression and maternal aggression in mated male and lactating female mice. It has been shown that such infection produced a significant inhibition, mainly of maternal aggression parameters and on offensive behaviours category which associated with this form of fighting. Infection with 4000 infective larvae of T.canis has however no significant effect on most parameters of social aggression in mated male mice. The suppressive effects on maternal fighting could be attributed to the fact that lactating females were more susceptible to this stage of infection. The muscular tone data in this study excluded the involvement of myorelaxation in the suppression of maternal aggression. Postmortem investigation of mated and lactating mice, shows the presence of substantial number of T.canis larvae which managed to migrate to the brain

Contaminación de suelos por huevos de toxocara sp en parques públicos y jardines de casas-habitación de la ciudad de México / Soil contamination with toxocara sp eggs in public parks and home gardens from Mexico city

Due to the high number of stray dogs and cats which defecate in public places in Mexico city (3 millions approximately), in addition to domestic dogs and cats, exists the potential risk to man of infection by toxocara sp eggs. A study to determine the contamination frequency by toxocara sp eggs in public parks, public flower beds, and home gardens in Mexico City, Distrito Federal, was carried out in the 1995 first semester. Fourteen hundred and five soil samples were collected from 156 public parks, 83 public flower beds and 42 home gardens across the 16 delegations in Mexico City, Distrito Federal. Samples were processed by the zinc sulfate centrifugal flotation method, and supernatants read by microscopy. Out of the whole 281 sampled sites, 12,5 percent were found contaminated with toxocara sp eggs. Positivity found was: 10,9 percent in public parks, 13,3 percent in public flower beds and 16,7 in home gardens. Ninety percent of the eggs were embryonated or larvaeted measuring 60 to 90 micrometers. The high contamination frecuencies found make necessary to prompt for public health measures granted the risk of infection acquisition spread on the most exposed population (children) provided that it is acquired via geophagia.

Toxascariasis as a cause of renal disease in children in Sharkia governorate, Egypt

84 children [40 males and 44 females] suffering from renal troubles were chosen, as well as 20 healthy children as a control group. Urine and stool of patients were examined and chosen to be free from parasitic infections other than Toxocara. Each child was subjected to history taking, full clinical examination, urine analysis, kidney function tests and differential leukocytic count, examination of sera and urine by ELISA and microprecipitin tests for Toxocara antibodies. ELISA revealed 10.7% of patients to be seropositive for toxocariasis versus 5.3% in control group. This difference was statistically insignificant. In urine, ELISA revealed 2 positive cases out of the 84 patients, while it was negative in control group. These 2 cases suffered from nephrotic syndrome. Microprecipitin test in sera was positive in 9.5% of patients and negative in control group. It was also negative in urine of patients and control group. Eosinophilia was found in 66.6% of seropositive patients. IgG antibodies to Toxocara were detected in males more than females between the age of 2 - 7 years, but insignificant. It was also found in 77.7% of rural compared with 22.2% of urban areas. This difference was statistically significant. It was concluded that toxocariasis should not be missed in the differential diagnosis of such renal diseases, especially those who are not respond to the traditional management

Geohelmintosis intestinales en el hombre y animales domésticos de sectores ribereños de la cuenca del río Valdivia Chile / Intestinal geohelminthosis in man and domestic animals in riverside sectors of Valdivia river basin, Chile

In march - october 1987 were analyzed 1295 coprological specimens in a sample of the human population who lives in riverside localities in the Valdivia river basin, Chile. A 23,6 for percent of examined persons presented infection by one or more helminth species. The prevalence of infection by ascaris lumbricoides, trichuris trichiura and trichostrongylidae gen. sp were 15,5; 12,7 and 0,2 for percent, respectively. The prevalence of human ascariosis and trichuriosis were greater in pre-school and school children. The sex of the host and prevalence of geohelminthosis did not show any relationship. Prevalences of ascariosis and trichuriosis were higher in persons from houses no sanitary fecal and water disposal. Over 35 for percent and 20,7 for percent of family groups showed infection by A. lumbricoides and T. trichiura, respectively in over 40 for percent of the members of each group. Fecal samples from domestic mammals revealed the following prevalences rates helminth infections: in dogs 19,0 and 15,2 for percent for toxocara canis and uncinaria stenocephala respectively, in cats 65,1 for percent for toxocara cati, and in pigs 25,4 and 3,2 for percent for ascaris suum and trichuris suis respectively. Some of these species are clearly demostrated agents of zoonoses

Experimental murine toxocara canis histopathological study of chronic renal infection, transplacental transmission and ultrastructural study of egg shell

Histopathological examination of kidney of Swiss albino mice, 21/2 months after infection with Toxocara canis eggs revealed various pictures of pathological affection. There was diffuse mesangioproliferative glomerulonephritis with mesangial expansion of most of glomeruli. Some glomeruli showed severe hyalinosis with marked adhesions to the bowman's capsule. The lumina of glomerular capillaries were markedly obliterated. There was also cystic dilation of tubules with proteinaceous casts. The interstitial tissue showed mild inflammatory edema. Chronic inflammatory cellular infiltration to form granulomatous inflammation was noticed. Transplacental transmission of Toxocara larvae was assessed in embryo of pregnant female Swiss albino mice which were infected with Toxocara eggs in the 1st week of pregnancy. The larvae were detected in the liver of embryo. Ultrastructural study of the egg shell revealed its formation of four layers, a thin uterine membrane with occasional small bulges, vitelline layer, thick homogenous layer, and fibrous lamellar and lipid layer