Toxocariasis ocular en el adulto asociada a cirugía de vitrectomía mínimamente invasiva / Adult ocular toxocariasis associated to minimally invasive vitrectomy

La toxocariasis es una zoonosis parasitaria. Se describen las alteraciones anatómicas y funcionales producidas por membranas que traccionan el polo posterior y la periferia de la retina, las cuales provocan hemorragia vítrea parcial asociada a neovascularización del disco óptico con membrana epirretiniana, y un agujero macular lamelar relacionado con la presencia de granuloma periférico. Se presenta un caso clínico de un paciente sano, quien comenzó con disminución de la agudeza visual del ojo izquierdo y se le diagnosticó, por cuadro clínico y examen oftalmológico con resultado positivo de la prueba de Toxocara, una toxocariasis ocular complicada. Se le realizó cirugía de vitrectomía mínimamente invasiva 23 G asociada a membranectomía, y pelado de la membrana limitante interna, así como endofotocoagulación con láser panretiniana. Se usó como tamponador al final de la cirugía el gas SF6 y el posicionamiento del paciente. Se aplicó tratamiento antiparasitario y esteroideo sistémico previo a la cirugía, y se obtuvieron resultados satisfactorios tanto anatómicos como funcionales del paciente(AU)

Toxocariasis is a parasitic zoonosis. A description is provided of the anatomical and functional alterations produced by membranes that pull the posterior pole and the periphery of the retina, causing partial vitreous hemorrhage associated to neovascularization of the optic disk with epiretinal membrane, and a lamellar macular hole related to the presence of peripheral granuloma. A clinical case is presented of a healthy male patient who started out with a decrease in the visual acuity of his left eye and was diagnosed with a complicated ocular toxocariasis based on his clinical status and ophthalmological examination with a positive toxocara test. Minimally invasive vitrectomy was performed: 23G associated to membranectomy and internal limiting membrane peeling, as well as panretinal laser endophotocoagulation, using patient positioning and gas (SF6) as tamponade at the end of surgery. Systemic steroid and antiparasitic treatment was provided before surgery, and satisfactory anatomical and functional results were obtained(AU)

Isolation of IgG Antibodies to Toxocara in Ankylosing Spondylitis Patients with Acute Anterior Uveitis

PURPOSE: Since few reports had been published on the prevalence of toxocariasis in ankylosing spondylitis (AS) patients with acute non-granulomatous anterior uveitis (ANGAU), the aim of this work was to determine the presence of antibodies against Toxocara canis in AS patients with ANGAU. METHODS: Thirty-six patients (14 female and 22 male) with AS were enrolled in the study. The history of ANGAU was accepted only if diagnosed by an ophthalmologist. The detection of IgG antibodies to T. canis was determined by enzyme-linked immunosorbent assay. In addition, antibodies to Ascaris lumbricoides were also tested to verify non-specific reactions. RESULTS: The prevalence of ANGAU in the AS patients was 58% (21 / 36), and 38% (8 / 21) of the patients with ANGAU were positive for antibodies to Toxocara, while 7% (1 / 15) of AS patients without ANGAU were positive for T. canis (p = 0.038, two tails; mid-p exact). No antibodies were detected to A. lumbricoides antigens in the serum samples of patients with AS. CONCLUSIONS: These data suggest that the seroprevalence of antibodies to T. canis is high in Mexican patients with AS-associated uveitis, suggesting a chronic asymptomatic toxocariosis, which could be associated with the pathogenesis of ANGAU; however, further larger-scale studies are needed to confirm this observation.

Manifestaciones cardiovasculares de la toxocariasis humana / Cardiovascular manifestations of human toxocariasis

La toxocariasis es una infección parasitaria producida por un helminto que en el ser humano no alcanza su estadio adulto. El hombre es para sus especies, Toxocara canis y Toxocara cati, un hospedador paraténico. Dicha infección puede producir el síndrome de larva migrans visceral, el síndrome de larva migrans ocular y la toxocariasis inaparente. En el síndrome de larva migrans visceral el compromiso de órganos puede incluir hígado, pulmón, piel, sistema nervioso, musculoesquelético, riñón y corazón. Sobre este último, cada vez se reconoce más la importancia que pueden tener las manifestaciones cardiovasculares de la toxocariasis y la relevancia clínica de considerarlas. En el presente artículo, haciendo una búsqueda sistemática de información, se revisan los principales aspectos clinicopatológicos de las manifestaciones cardiovasculares de la toxocariasis incluyendo su fisiopatología, hallazgos de laboratorio, diagnóstico y opciones terapéuticas, con el objeto de llamar la atención acerca de la importancia de esta zoonosis y su relevancia para la medicina cardiovascular en adultos y en niños.

Toxocariasis is a parasitic infection produced by helminths that cannot reach their adult stage in humans. For their etiological species (Toxocara canis and Toxocara cati), man is a paratenic host. Infection by such helminths can produce a variety of clinical manifestations, such as: visceral larvae migrans syndrome, ocular larvae migrans syndrome and covert toxoca-riasis. In the visceral larvae migrans syndrome, the organs that are mainly involved include liver, lungs, skin, nervous system, muscles, kidneys and the heart. Regarding the latter, the importance of cardiovascular manifestations in toxocariasis, as well as its clinical relevance, has increasingly begun to be recognized. The current article is based on a systematic information search, focused mainly on the clinical and pathological aspects of cardiovascular manifestations in toxocariasis, including its pathophysiology, laboratory findings, diagnosis and therapeutical options, with the objective of highlighting its importance as a zoonosis and its relevance to the fields of cardiovascular medicine in adults and children.

Parálisis de Bell y dolor facial asociados con infección por Toxocara sp / Bell's palsy and facial pain associated with toxocara infection

Objectives: Toxocarosis involving cranial nerves is extremely rare and almost exclusively concerns the optic nerve. Toxocarosis involving the seventh cranial nerve has not been reported. Case report: A 33y male developed left-sided Bell's palsy two days after left-sided otalgia 6y before. Despite extensive diagnostic work-up at that time the cause of Bell's palsy remained unknown. During the following years Bell's palsy slightly improved but retromandibular pain remained almost unchanged and he developed enlarged lymph nodes along the jugular veins, submandibularly, and in the trigonum caroticum. Re-evaluation 6y later revealed an increased titer of serum antibodies against Toxocara canis and a positive Westernblot for Toxocara canis ES-antigen. Despite absent eosinophilia in the serum, toxocarosis was diagnosed and a therapy with albendazole initiated, with benefit for retromandibular pain, but hardly for Bell's palsy or enlarged lymph nodes. CSF investigations after albendazole revealed a positive Westernblot for antibodies against toxocara but absent pleocytosis or eosinophilia, and negative PCR for Toxocara canis. Conclusions: Visceral larva migrans due to Toxocara canis may be associated with Bell's palsy, retromandibular pain, and lymphadenopathy. A causal relation between Bell's palsy and the helminthosis remains speculative. Adequate therapy years after onset of the infestation may be of limited benefit.

Objetivos: La toxocarosis que compromete los nervios craneales es extremadamente infrecuente y afecta casi exclusivamente al nervio óptico. No ha sido comunicada la toxocarosis que afecte al séptimo nervio cranial por lo que se expone un caso clínico. Caso clínico: Varón de 33 años que había presentado seis años antes, una otalgia izquierda seguida dos días más tarde de una parálisis de Bell ipsilateral. A pesar de un exhaustivo estudio, la causa de esta parálisis quedó sin etiología. En los años siguientes la parálisis mejoró moderadamente pero persistió un dolor retromandibular casi sin variaciones y el paciente desarrolló adenopatías en la cadena yugular, submandi-bulares y en el triángulo carotídeo. Una re-evaluación efectuada seis años más tarde detectó un título elevado de anticuerpos contra Toxocara canis y un antígeno ES de T. canis positivo mediante Westernblot. A pesar de no haber eosinofilia en la sangre, se diagnosticó una toxoca-rosis iniciándose terapia con albendazol, con lo cual se observó una reducción del dolor retro-mandibular aunque escaso beneficio sobre la parálisis de Bell y los ganglios comprometidos. El líquido cefalorraquídeo analizado después de haberse efectuado la cura con albendazol reveló un test de Westernblot positivo para anticuerpos anti-toxocara, en ausencia de pleocitosis o eosinofilia, y una RPC para Toxocara canis negativa. Conclusiones: El síndrome de larva migrans visceral debido a T. canis puede asociarse con parálisis de Bell, dolor retroman-dibular y linfoadenopatías. La relación causal entre la parálisis de Bell y la helmintosis permanece en el plano especulativo. La terapia anti-parasitaria realizada años tras la instalación de una infestación puede tener un beneficio aunque limitado.

Behavioral changes in Rattus norvegicus experimentally infected by Toxocara canis larvae / Alterações de comportamento em Rattus norvegicus experimentalmente infectados por larvas de Toxocara canis

Toxocara canis is a common canine nematode parasite and one of its possible transmission mechanisms is the predation of infected rodents by canids. Fifty Rattus norvegicus were used to study behavioral alterations in rodents infected by T. canis larvae. The rats were divided into three groups: G1, 20 rats infected with 300 T. canis eggs; G2, 20 rats infected with 2,000 T. canis eggs; and G3, 10 non-infected rats. Thirty and 60 days post-infection, rats from all the groups were submitted to an open-field apparatus for five min and subsequently, to an elevated plus-maze apparatus, again for five min. The data obtained indicated improvement in mobility (total locomotion time and rearing frequency) and exploratory behavior in infected rats, principally in G2, which provides some support for the hypothesis that behavioral alterations in rodents infected by Toxocara canis larvae enhance the transmission rate of this ascarid to dogs.

Toxocara canis é um nematódeo parasita habitual do intestino delgado de cães. Um dos mecanismos conhecidos de transmissão para cães é representado pela predação de pequenos roedores que, como hospedeiros paratênicos albergam larvas de Toxocara canis em seus tecidos. Para avaliar a ocorrência de alterações de comportamento em roedores infectados por Toxocara canis 50 exemplares de Rattus norvegicus foram utilizados no experimento. Os animais foram divididos em três grupos: G1 - 20 ratos infectados com 300 ovos de Toxocara canis; G2 - 20 ratos infectados com 2.000 ovos de Toxocara canis e G3 - 10 ratos sem infecção. Trinta e 60 dias após a infecção avaliou-se a ocorrência de alterações comportamentais nos três grupos submetendo os animais, primeiramente, a uma arena de campo aberto durante cinco minutos e, a seguir, a labirinto em cruz elevado por mais cinco minutos. Os resultados obtidos indicaram aumento significativo da mobilidade (tempo total de movimentação e número de vezes em que os animais se levantaram nas patas traseiras) e comportamento exploratório nos ratos infectados, principalmente nos pertencentes ao G2, sugerindo a ocorrência de alterações comportamentais que favoreceriam a transmissão de Toxocara canis para canídeos por meio de relação presa-predador.

Toxocara canis y asma bronquial / Toxocara canis and bronchial asthma

A fin de evaluar la relación entre la infección por Toxocara canis y los síntomas del asma bronquial en niños de una región subtropical con alta prevalencia de toxocariosis, se estudiaron 47 niños con asma y 53 sin asma como grupo control. Se efectuó el examen físico completo, registrándose datos clínicos y epidemiológicos. En los niños con asma se categorizó el patrón de presentación, frecuencia y gravedad de los síntomas con una escala de I a IV. Se investigó la presencia de anticuerpos anti-Toxocara canis en ambos grupos mediante el método de ELISA en fase sólida, empleando antígeno de excreción/secreción y se efectuó dosaje de Ig E total. Los resultados muestran una seropositividad del 55% en el total de los niños, del 57.4% en los niños con asma y del 52.8% en los controles. En los niños con sintomatología más grave (grado II, III y IV) hubo un 67.7% de seropositivos, mientras que en los niños con síntomas de grado I la seropositividad fue de 37.5% (p = 0.0470). La infección por T. canis actuaría como un co-factor agravante de los síntomas del asma bronquial.

In order to evaluate the association between the infection by Toxocara canis and the symptoms of asthma in children from a subtropical region with high prevalence of toxocariasis, 47 asthmatic children and 53 non-asthmatics as a control group were studied. A complete physical examination was performed and clinical and epidemiological data were registered. In asthmatic children the frequency and severity of symptoms were classified in grades I to IV. The presence of anti-Toxocara canis antibodies in both groups was evaluated employing a solid phase ELISA method with excretion/secretion antigens, and total Ig E was also measured. Results showed a total seropositivity of 55%, 57.4% in children with asthma and 52.8% in the control group. Among asthmatics with severe symptoms (grade II, III and IV), there was a 67.7% of seropositivity while in children with symptoms of grade I there was a 37.5% (p = 0.0470). The infection with T. canis could act as a co-factor increasing the severity of the symptoms of bronchial asthma.

Human toxocariasis: contribution by Brazilian researchers / Toxocaríase humana: contribuição dos pesquisadores brasileiros

In the present paper the main aspects of the natural history of human infection by Toxocara larvae that occasionally result in the occurrence of visceral and/or ocular larva migrans syndrome were reviewed. The contribution by Brazilian researchers was emphasized, especially the staff of the Tropical Medicine Institute of São Paulo (IMT).

São abordados os principais aspectos da história natural da infecção humana por larvas de Toxocara que pode resultar na ocorrência da síndrome de larva migrans visceral e/ou ocular. Deu-se destaque, principalmente, à contribuição de pesquisadores brasileiros e, em especial, aos pertencentes ao quadro do Instituto de Medicina Tropical de São Paulo.

Toxocariasis Might be an Important Cause of Atopic Myelitis in Korea

Atopic myelitis is defined as myelitis with atopic diasthesis but the cause is still unknown. Toxocariasis is one of the common causes of hyperIgEaemia that may lead to neurologic manifestations. The purpose of this study was to evaluate the sero-prevalence of Toxocara specific IgG Ab among the atopic myelitis patients. We evaluated the medical records of 37 patients with atopic myelitis whose conditions were diagnosed between March 2001 and August 2007. Among them, the 33 sera were analyzed for specific serum IgG Ab to Toxocara excretory-secretory antigens (TES). All of 37 patients had hyperIgEaemia. Specific IgE to D. pteronyssinus and D. farinae was detected in 22 (64.7%) and 34 (100%) patients, respectively, of the 34 patients. Thirty-one of 33 patients (93.9%) were found to be positive by TES IgG enzyme-linked immunosorbent assay (ELISA). Based on the image findings of eosinophilic infiltrations in the lung and liver, 8 patients had positive results. These results inferred that the prevalence of toxocariasis was high in patients with atopic myelitis. Our results suggest that toxocariasis might be an important cause of atopic myelitis and Toxocara ELISA is essential for evaluating the causes of atopic myelitis.

Impact of Toxocariasis in Patients with Unexplained Patchy Pulmonary Infiltrate in Korea

Toxocariasis is one of the causes of pulmonary eosinophilic infiltrate that is increasing in Korea. This study was designed to identify the prevalence of toxocara seropositivity in patients with unexplained pulmonary patchy infiltrate and to evaluate associated factors. We evaluated 102 patients with unexplained pulmonary patchy infiltrate on chest computed tomography (CT) scan. As a control set, 116 subjects with normal chest CT were also evaluated. History of allergic disease, drug use, parasitic disease and raw cow liver intake were taken. Blood eosinophil count and total IgE level were measured. Specific serum IgG antibody to Toxocara canis larval antigen and specific IgG antibodies to 4 other parasites were measured by enzymelinked immunosorbent assay (ELISA). In the infiltrate group, 66.7% subjects were toxocara seropositive whereas 22.4% of the control group were seropositive (p< 0.001). In the infiltrate group, patients with a history of eating raw cow liver (odds ratio [OR], 7.8) and patients with eosinophilia (OR, 5.2) had a higher incidence of toxocara seropositivity. Thirty-five percent of toxocara seropositive patients with infiltrate exhibited migrating infiltrate and 48% had decreased infiltrate on the follow- up CT. We recommend that toxocara ELISA should be performed in patients with unexplained pulmonary patchy infiltrate, and that the eating of raw cow liver should be actively discouraged.

Ocular lesions in gerbils (Meriones unguiculatus) infected with low larval burden of Toxocara canis: observations using indirect binocular ophthalmoscopy / Lesões oculares em gerbils (Meriones unguiculatus) infectados com baixo número de larvas do Toxocara canis: observações com oftalmoscopia binocular indireta

To study the frequency of ocular lesions in 30 gerbils infected with 100 embryonated eggs of Toxocara canis, indirect binocular ophthalmoscopy was performed 3, 10, 17, 24, 31 and 38 days after infection. All the animals presented larvae in the tissues and 80 percent presented ocular lesions. Hemorrhagic foci in the choroid and retina were present in 92 percent of the animals with ocular lesions. Retinal exudative lesions, vitreous lesions, vasculitis and retinal detachment were less frequent. Mobile larvae or larval tracks were observed in four (13.3 percent) animals. Histological examination confirmed the ophthalmoscopic observations, showing that the lesions were focal and sparse. In one animal, there was a larva in the retina, without inflammatory reaction around it. The results demonstrated that gerbils presented frequent ocular lesions after infection with Toxocara canis, even when infected with a small number of embryonated eggs. The lesions observed were focal, consisting mainly of hemorrhages with signs of reabsorption or inflammation in different segments of eye, and differing from the granulomatous lesions described in ocular larva migrans in humans.

Para verificar a freqüência de lesões oculares em 30 gerbils infectados com 100 ovos larvados de Toxocara canis foi realizada a oftalmoscopia binocular indireta nos dias 3, 10, 17, 24, 31 e 38 após a infecção.Todos os animais apresentavam larvas nos tecidos e 80 por cento apresentavam lesões oculares, dos quais 92 por cento tinham lesões hemorrágicas focais na coróide e na retina. Lesões exudativas da retina, lesões do vítreo, vasculite e descolamento da retina foram menos freqüentes. Larva móvel ou traços de larva em quatro (13,3 por cento) animais. O estudo histológico confirmou as observações da oftalmoscopia, mostrando que as lesões eram focais e esparsas. Em um animal havia uma larva na retina, sem reação inflamatória em torno dela. Os resultados demonstraram que os gerbils apresentam freqüentes lesões oculares após infecção com o Toxocara canis mesmo quando infectados com pequeno número de ovos larvados. As lesões observadas eram focais, principalmente focos de hemorragia com sinais de reabsorção ou focos de inflamação nos diferentes segmentos do olho, diferentes das lesões granulomatosas descritas na larva migrans ocular humana.

Toxocariasis and Ingestion of Raw Cow Liver in Patients with Eosinophilia

Ingestion of raw animal liver has been suggested as a possible mode of infection of human toxocariasis. We evaluated the relationship between toxocariasis and the ingestion of raw meat in patients with eosinophilia of unknown etiology. The study population consisted of 120 patients presenting with peripheral blood eosinophilia (> 500 cells/microliter or > 10% of the white blood cell count). They were divided into 2 groups: 104 seropositive patients based on a Toxocara excretory-secretory IgG ELISA and 16 seronegative patients. While 25.0% of seronegative patients had a recent history of eating raw cow liver, 87.5% of seropositive patients had this history. Multivariate statistical analysis showed that a recent history of eating raw cow liver was related to an increased risk of toxocariasis. Collectively, it is proposed that raw cow liver is a significant infection source of toxocariasis in the patients with eosinophilia of unknown etiology.

Neurotoxocarosis

Infection of humans with embryonated eggs of Toxocara canis (larva migrans) remains asymptomatic, or results in covert or common toxocarosis, visceral larva migrans syndrome, or ophthalmologic and neurologic impairment. Though neurological manifestations of Toxocara canis larvae are rare, toxocarosis remains an important differential diagnosis of various neurological disorders. Manifestations of the central nervous system are dementia, meningo-encephalitis, myelitis, cerebral vasculitis, epilepsy, or optic neuritis. Manifestations of the peripheral nervous system comprise radiculitis, affection of cranial nerves, or musculo-skeletal involvement. If toxocarosis is neglected, ignored, or refused as a differential of these abnormalities, it may be easily overlooked for years. Early recognition and treatment of the infection is, however, of paramount importance since it reduces morbidity and mortality and the risk of secondary superinfection. Like the visceral manifestations, neurological manifestations of toxocarosis are treated by benzimidazole components, most frequently albendazole, corticosteroids, or diethylcarbamazine. If detected and treated early, the prognosis of neurological manifestations of toxocarosis is favourable.

Infecção humana com ovos embrionados de Toxocara canis (larva migrans) pode permanecer assintomática ou resultar em toxocaríase acentuada ou comum, síndrome da larva migrans visceral ou manifestações neurológicas ou oftalmológicas. Embora manifestações neurológicas das larvas de Toxocara canis sejam raras, a toxocaríase permanece como importante diagnóstico diferencial de várias manifestações neurológicas. Manifestações do sistema nervoso central são demência, meningoencefalite, mielite, vasculite cerebral, epilepsia, ou neurite ótica. Manifestações do sistema nervoso periférico compreendem radiculite, agressão de nervos cranianos ou envolvimento músculo-esquelético. Se a toxocaríase é negligenciada, ignorada, ou recusada como diferencial destas anormalidades, ela pode ser facilmente desapercebida por anos. Reconhecimento precoce de tratamento da infecção é portanto de fundamental importância uma vez que reduz sua morbidade e mortalidade e o risco de superinfecção secundária. Da mesma maneira que as manifestações viscerais, as neurológicas são tratadas por benzimidazólicos, mais freqüentemente albendazole, corticosteróides ou dietilcarbamazine. Se detectado e tratado precocemente, o prognóstico das manifestações neurológicas da toxocaríase é favorável.

Estudo clínico-epidemiológico da toxocaríase em população infantil / Clinical-epidemiological study of toxocariasis in a pediatric population

OBJETIVO: A diversidade de manifestações clínicas da toxocaríase e sua relação com asma motivaram este estudo, cujo objetivo foi estudar a soropositividade de T. canis nas crianças atendidas no serviço público de saúde e sua associação com variáveis clínicas, epidemiológicas e laboratoriais. MÉTODOS: Este estudo é de corte transversal e controlado. Foram realizadas sorologias em 208 crianças de 1 a 14 anos de idade, atendidas nos ambulatórios de Pediatria, Imunologia e Pneumologia Pediátrica da Universidade de Santo Amaro, no período de janeiro de 2000 a janeiro de 2001. Os anticorpos foram detectados por ELISA usando-se antígeno de excreção e secreção do T. canis.. Foi utilizado teste qui-quadrado para associações da soropositividade para T. canis (título > 1:320) com cães filhotes domiciliares, contato com terra, geofagia, onicofagia, escolaridade materna, asma, tosse crônica, pneumonias de repetição, manifestações cutâneas, rinite, hepatomegalia, esplenomegalia, dor abdominal, anemia, eosinofilia, imunoglobulinas, parasitoses e desnutrição, e método de análise de variância por postos de Kruskal-Wallis para comparação média dos soropositivos e soronegativos, sendo significante p < 0,05. RESULTADOS: A soroprevalência foi 54,8 por cento, com média etária de 6,5 anos; nos soronegativos, 5,8 anos (não significante), também não houve diferença quanto ao sexo. A soropositividade foi significante com: cães filhotes domiciliares, contato com terra, hepatomegalia, asma, eosinofilia, IgE aumentada e desnutrição pregressa. CONCLUSAO: A soroprevalência encontrada foi alta. A infecção pelo T. canis deve ser investigada em crianças com fatores de risco como presença de cães filhotes domiciliares e contato com terra, em portadores de hepatomegalia e/ou asma, com eosinofilia ou aumento de IgE.

Diagnostic importance of serological methods and eosinophilia in tissue parasites.

This case-control study was carried out to investigate whether eosinophilia is a common finding in parasitic diseases and to determine the prevalence of the parasitic diseases in definitive groups. Toxocariasis and fasciolosis were investigated in patients with eosinophilia, patients with non-eosinophilia, and healthy controls. All cases were analyzed for antibodies against Toxocara canis and Fasciola hepatica by modified enzyme-linked immunosorbent assay (ELISA) employing, as antigen, excretory/secretory products of Toxocara and Fasciola (ES-ELISA). Seropositivity was determined in 39 (29.1%) and 12 (8.9%) toxocariasis and fasciolosis patients with eosinophilia respectively. The seropositivity was found in 26 (19.4%) and 5 (3.7%) toxocariasis and fasciolosis patients without eosinophilia respectively. The seropositivity was found in 13 (15.5%) and 1 (1.2%) toxocariasis and fasciolosis patients in the control group. The total seropositivity in both toxocariasis and fasciolosis in the eosinophilic group (8.5%) increased significantly compared to patients without eosinophilia (23.1%) and healthy controls (6.6%) (chi2:6.343, p < 0.05 and chi2:10.293, p < 0.01). Eosinophilia correlated with antibodies against Toxocara and E. hepatica. The results suggest that serological methods can be used for diagnosis of parasitic infections in tissue. Thus, the actual prevalence of tissue parasites can be revealed particularly in developing and emerging countries.

Toxocarosis en Chile: serie clínica en un centro de pediatría ambulatoria / Toxocarosis in Chile: clinical serie in a pediatric ambulatory center

Este trabajo tuvo como objetivo averiguar la frecuencia y presentación clínica de la toxocarosis en una población infantil. Para ello se realizó entre febrero y agosto de 1997, un estudio descriptivo en una población menor de 15 años, consultante a la Unidad de pediatría Ambulatoria del Centro Médico San Joaquín de la Universidad Católica de Chile. Los niños con eosinofilia (400 o más cel/mm) fueron elegidos para el estudio. La infección por toxocara se diagnosticó mediante la medición del antígeno somático por técnica de ELISA, con dilución de al menos 1/64. Durante el período se realizaron 7.898 consultas, tomándose 364 hemogramas. Se encontró eosinofilia en 24 niños (6,6 por ciento) (rango: 400-9.135 cel/mm). Ocho de éstos fueron positivos para toxocara (30 por ciento). El promedio de edad del grupo de estudio fue 4 años 6 meses (rango: 2 años 4 meses). Todos vivían en centros urbanos y habían tenido contacto con perros, gatos y 5 de los ocho practicaban geofagia. El hemograma fue tomado por adenitis (n=2), mal incrementado ponderal (n=2), bronquitis obstructiva (n=2), exatema (n=1). Sólo en un caso fue positivo el examen oftalmológico, 6/8 pacientes tenían otra parasitosis

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.