Abstract Both HIV-1 and Toxoplasma gondii are able to invade central nervous system and affect its functionality. Advanced HIV-1 infection has been associated with defects in immune response to T. gondii, leading to reactivation of latent infections and the appearing of toxoplasmic encephalitis. This study evaluated changes in the immune response to T. gondii in different stages of HIV infection. Immune response to T. gondii was assessed studying cytokine production in response to parasite antigens in HIV-1-infected/T. gondii-noninfected (P1), HIV-1/T. gondii co-infected (P2), HIV-1-non-infected/T. gondiinon-infected (C1) and HIV-1-non-infected/T. gondii-infected (C2) individuals. Patients (P1 and P2) were divided in early/asymptomatic (P1A, P2A) or late/symptomatic (P1B/C, P2B/C) according to peripheral blood CD4+ T lymphocyte counts (>350 or <350/μL, respectively). The HIV-1 infection, from early/asymptomatic stages, was associated with significant lower production of IL-2, TNF-α and IFN-γ in response to T. gondii, when P2 patients were compared with C2 controls. These early defects may impair anti-parasitic response in co-infected patients, allowing to reactivation of parasitic latent infection, enhancing the risk of CNS damage and impairment of neurocognitive functions.

Resumen Tanto el Virus de Inmunodeficiencia Humana-1 (VIH-1), como el protozoo Toxoplasma gondii son capaces de infectar al ser humano e invadir su sistema nervioso central (SNC). En individuos inmunocompetentes T. gondii causa infecciones crónicas, generalmente asintomáticas; sin embargo, la inmunodeficiencia asociada a etapas avanzadas de la infección por VIH-1, se relaciona con la pérdida del control de la infección parasitaria latente y enfermedades graves a nivel del SNC, como encefalitis toxoplásmica. Este trabajo tuvo como objetivo evaluar la evolución de la respuesta inmunitaria contra T. gondii en pacientes co-infectados con VIH-1, en distintas etapas de la infección viral. La respuesta contra T. gondii se evaluó a través de la producción in vitro de citosinas en respuesta a antígenos parasitarios, en individuos con serología positiva para VIH-1 y negativa para T. gondii (P1), positiva para VIH-1 y T. gondii (P2), negativa para VIH-1 y T. gondii (C1) y negativa para VIH-1 y positiva para T. gondii (C2). Los pacientes (P1 y P2) se agruparon en tempranos/asintomáticos (P1A, P2A) o tardíos/sintomáticos (P1B/C, P2B/C) de acuerdo a su recuento de linfocitos T CD4+ en sangre periférica (>350 o <350 células/μL, respectivamente). La infección por VIH-1, desde etapas tempranas, se asoció con una producción de IL-2, TNF-α e IFN-γ en respuesta a T. gondii significativamente menor. Estos defectos pueden entorpecer la respuesta anti-T. gondii en pacientes co-infectados, aumentando la posibilidad de reactivación de las infecciones latentes, lo que representa un riesgo para la integridad y funcionalidad del SNC.

We describe the eleventh major outbreak of foodborne Trypanosoma cruzi transmission in urban Venezuela, including evidence for vertical transmission from the index case to her fetus. After confirming fetal death at 24 weeks of gestation, pregnancy interruption was performed. On direct examination of the amniotic fluid, trypomastigotes were detected. T. cruzi specific-polymerase chain reaction (PCR) also proved positive when examining autopsied fetal organs. Finally, microscopic fetal heart examination revealed amastigote nests. Acute orally transmitted Chagas disease can be life threatening or even fatal for pregnant women and unborn fetuses owing to vertical transmission. There is therefore an urgent need to improve national epidemiologic control measures.

El presente trabajo describe la distribución geográfica actual de las principales especies de caracoles de agua dulce incriminadas como hospedadoras intermediarias de Schistosoma mansoni (4 especies de Biomphalaria), Fasciola hepatica (4 especies de Galba y Pseudosuccinea columella) y Paragonimus sp. (Aroapyrgus vivens) en Venezuela. Adicionalmente, se discute el status epidemiológico así como el hábitat de ocurrencia de cada una de estas especies, a fin de brindar información base para la vigilancia, manejo y control de los hospedadores intermediarios que participan en los ciclos vitales de los agentes causales de la esquistosomiasis, fascioliasis y paragonimiasis, que constituyen enfermedades desatendidas actualmente en Venezuela.

This study describes the current distribution patterns of the main species of freshwater mollusks incriminated as intermediate hosts of Schistosoma mansoni (Biomphalaria, 4 species), Fasciola hepatica (Galba, 4 species and Pseudosuccinea columella), and Paragonimus sp. (Aroapyrgus vivens) in Venezuela. Additionally, the epidemiological status and the main aquatic habitats of each species are discussed in order to bring basic information to help the surveillance and control of these neglected tropical diseases in Venezuela.

Orally transmitted Chagas disease has become a matter of concern due to outbreaks reported in four Latin American countries. Although several mechanisms for orally transmitted Chagas disease transmission have been proposed, food and beverages contaminated with whole infected triatomines or their faeces, which contain metacyclic trypomastigotes of Trypanosoma cruzi, seems to be the primary vehicle. In 2007, the first recognised outbreak of orally transmitted Chagas disease occurred in Venezuela and largest recorded outbreak at that time. Since then, 10 outbreaks (four in Caracas) with 249 cases (73.5% children) and 4% mortality have occurred. The absence of contact with the vector and of traditional cutaneous and Romana’s signs, together with a florid spectrum of clinical manifestations during the acute phase, confuse the diagnosis of orally transmitted Chagas disease with other infectious diseases. The simultaneous detection of IgG and IgM by ELISA and the search for parasites in all individuals at risk have been valuable diagnostic tools for detecting acute cases. Follow-up studies regarding the microepidemics primarily affecting children has resulted in 70% infection persistence six years after anti-parasitic treatment. Panstrongylus geniculatushas been the incriminating vector in most cases. As a food-borne disease, this entity requires epidemiological, clinical, diagnostic and therapeutic approaches that differ from those approaches used for traditional direct or cutaneous vector transmission.

FUNDAMENTO: A doença de Chagas afeta mais de 15 milhões de pessoas em todo o mundo. Embora a transmissão vetorial tenha diminuído, a transmissão oral tornou-se relevante. Recentemente, nosso grupo publicou as características clínicas e epidemiológicas do maior surto relatado até hoje da doença de Chagas transmitida oralmente. OBJETIVO: Descrever alterações eletrocardiográficas que ocorrem na população de estudo durante o surto causado pela ingestão de suco de goiaba contaminado. MÉTODOS: Avaliamos 103 casos positivos, dos quais 76 (74%) tinham <18 anos de idade (média das idades: 9,1 ± 3,1 anos) e 27 (26%) tinham >18 anos (média das idades: 46 ± 11,8 anos). Todos os pacientes foram submetidos a avaliações clínicas e ECG. Caso os pacientes apresentassem palpitações ou alterações evidentes do ritmo na linha basal, o monitoramento de ECG ambulatorial seria realizado. RESULTADOS: Um total de 68 casos(66%;53 crianças e15 adultos) apresentaram anormalidades no ECG. Além disso, 69,7% (53/76) daqueles com idade < 18anos e 56% (15/27) daqueles com idade >18 anos apresentaram alguma alteração no ECG(p = ns). Anormalidades de ST-T foram observadas em 37,86% casos (39/103) e arritmias foram evidente sem 28,16% casos(29/103). Alterações de ST ocorreram em 72% daqueles com idade < 18 anos em comparação aos de > 18 anos (p < 0,0001). CONCLUSÃO: Este estudo relata o maior número de casos no mesmo surto de doença de Chagas causada por contaminação oral, com ECGs relatados. As alterações no ECG que sugerem miocardite aguda e arritmias foram as anormalidades encontradas com maior frequência.

BACKGROUND: Chagas disease affects more than 15 million people worldwide. Although vector-borne transmission has decreased, oral transmission has become important. Recently, our group published the clinical and epidemiological characteristics of the largest outbreak of orally transmitted Chagas disease reported till date. OBJECTIVE: To describe electrocardiographic changes occurring in the study population during the outbreak caused by ingestion of contaminated guava juice. METHODS: We evaluated 103 positive cases, of which 76 (74%) were aged <18 years (average age: 9.1 ± 3.1 years) and 27 (26%) were aged > 18 years (average age: 46 ± 11.8 years). All patients underwent clinical evaluations and ECG. If the patients had palpitations or evident alterations of rhythm at baseline, ambulatory ECG monitoring was performed. RESULTS: A total of 68 cases (66%; 53 children and 15 adults) had ECG abnormalities. Further, 69.7% (53/76) of those aged < 18 years and 56% (15/27) of those aged >18 years showed some ECG alteration (p = ns). ST-T abnormalities were observed in 37.86% cases (39/103) and arrhythmias were evident in 28.16% cases (29/103). ST alterations occurred in 72% of those aged <18 years compared with 19% of those aged >18 years (p < 0.0001). CONCLUSIONS: This study reports the largest number of cases in the same outbreak of acute Chagas disease caused by oral contamination, with recorded ECGs. ECG changes suggestive of acute myocarditis and arrhythmias were the most frequent abnormalities found.

Orally transmitted Chagas disease (ChD), which is a well-known entity in the Brazilian Amazon Region, was first documented in Venezuela in December 2007, when 103 people attending an urban public school in Caracas became infected by ingesting juice that was contaminated with Trypanosoma cruzi. The infection occurred 45-50 days prior to the initiation of the sampling performed in the current study. Parasitological methods were used to diagnose the first nine symptomatic patients; T. cruzi was found in all of them. However, because this outbreak was managed as a sudden emergency during Christmas time, we needed to rapidly evaluate 1,000 people at risk, so we decided to use conventional serology to detect specific IgM and IgG antibodies via ELISA as well as indirect haemagglutination, which produced positive test results for 9.1%, 11.9% and 9.9% of the individuals tested, respectively. In other more restricted patient groups, polymerase chain reaction (PCR) provided more sensitive results (80.4%) than blood cultures (16.2%) and animal inoculations (11.6%). Although the classical diagnosis of acute ChD is mainly based on parasitological findings, highly sensitive and specific serological techniques can provide rapid results during large and severe outbreaks, as described herein. The use of these serological techniques allows prompt treatment of all individuals suspected of being infected, resulting in reduced rates of morbidity and mortality.

La Enfermedad de Chagas o Tripanosomiasis Americana está adquiriendo cada vez mayor importancia en la región amazónica de Venezuela, en la cual hasta ahora se carecía de información de la presencia de Trypanosoma cruzi en triatóminos, reservorios y humanos, particularmente para el estado Bolívar, el estado de mayor superficie del país, situado al sur del río Orinoco. Cuatro ejemplares de Triatoma maculata fueron recolectados en el peridomicilio de la comunidad de Maniapure, en el municipio Cedeño. En dos de los ejemplares se determinó la infección natural por Trypanosoma cruzi al examen al fresco de heces con presencia de tripomastigotos metacíclicos infectantes. Los parásitos fueron inoculados en modelos murinos y aislados en cultivos para su caracterización molecular. Se confirmó el diagnóstico de este parásito por pruebas parasitológicas y moleculares, caracterizándose los aislados como TcI. La importancia de estos hallazgos pioneros podría motivar el estudio de la transmisión vectorial de la Enfermedad de Chagas en este estado catalogado como no endémico.

American Trypanosomiasis or Chagas disease is becoming increasingly important in the Amazon region of Venezuela, in which up to now information was lacking of the presence of Trypanosoma cruzi in triatomins, reservoirs and humans, particularly for Bolivar State, the State with the largest territory of the country, located in the South of the Orinoco River. Four specimens of Triatoma maculata were collected in the peri-domiciliar area of the community of Maniapure, in the Cedeño municipality. Two of these individuals were found naturally infected with Trypanosoma cruzi upon examination of fresh stool with presence of metacyclic trypomastigotes. Parasites were inoculated in murine models and isolated for molecular characterization. Parasite isolates were molecularly characterized as TcI. The importance of these pioneering findings should motivate the study of the vector or oral transmission of Chagas disease in this non endemic State of Venezuela.

La infección por Echinococcus sp. es hipoendémica en Venezuela. Sólo cuatro casos de hidatidosis autóctona por E. vogeli han sido reportados, tres de ellos en la región de la Guayana venezolana. En Febrero del año 2009 se realizó el diagnóstico clínico-sero-epidemiológico de hidatidosis poliquística en una paciente femenina de la etnia Yanomami, procedente de Parima B, Alto Orinoco, en la Amazonía venezolana. Se resolvió con tratamiento médico y quirúrgico por laparoscopia y se evidenció en el quiste la presencia de ganchos rostelares compatibles con E. vogeli. En Abril del 2009 en una segunda paciente Yanomami de igual procedencia, se le diagnosticó hidatidosis por E. vogeli siendo operada exitosamente por cirugía laparoscópica asistida por robot. Dos casos humanos en una misma población y la presencia de factores de riesgo como la tenencia de perros domésticos y la comunicación por informantes indígenas del hallazgo de quistes en hígados de animales de cacería (Cuniculus paca o lapa y Dasyprocta sp. o picure), hacen pensar en transmisión activa en la cuenca del Alto Orinoco y en zonas selváticas de la Guayana venezolana. El presente, es el primer registro de casos de hidatidosis poliquística en indígenas de la etnia Yanomami.

Infection by Echinococcus sp. is hypoendemic in Venezuela. Only four cases of autochthonous E. vogeli hydatidosis have been reported, including three in the Venezuelan region of Guayana. In February 2009, based on epidemiological data, signs and symptoms and serological tests, a female patient of the Yanomami ethnic group, was diagnosed with a polycystic hydatid disease in Parima B, Alto Orinoco, in the Venezuelan Amazon. Rostellar hooks compatible with E. vogeli were found in the cyst. It was resolved with medical and surgical treatment by laparoscopy. A second Yanomami patient from the same location was diagnosed with E. vogeli hydatidosis in April 2009, being successfully operated with robot-assisted laparoscopy. Two human cases in the same population and the presence of risk factors such as domestic dog ownership and findings of cysts in livers of hunted animals (such as Cuniculus and Dasyprocta sp.) reported by indigenous informants, suggest active transmission in the Upper Orinoco basin and forested areas of the Venezuelan Guayana. These are the first reported cases of polycystic hydatid disease of the Yanomami ethnic group.

Se describe el proceso de investigación clínico-epidemiológica y de laboratorio que permitió establecer el nexo entre un caso de Enfermedad de Chagas en fase aguda aislado y una comunidad escolar urbana, así como la estrategia de diagnóstico y tratamiento de una emergencia médica para evitar mayor severidad clínica y mortalidad.

The clinical, laboratory and epidemiological investigations that established the connection between the index case of an acute episode of Chagas disease and an orally acquired outbreak in an urban school in Caracas are described. The strategy used for early diagnosis and treatment of this medical emergency prevented major clinical severity and mortality.

Paragonimus sp. es un trematodo que causa inflamación crónica del pulmón en mamíferos carnívoros y en el hombre, constituyendo un problema de salud pública en países asiáticos y latinoamericanos. Los trematodos poseen enzimas que facilitan la penetración y migración en diferentes hospederos a fin de garantizar su ciclo evolutivo. Con el objetivo de evaluar la diversidad enzimática de la fracción soluble (FSPA, 100.000 g) de un aislado venezolano de adultos de Paragonimus sp. se realizaron determinaciones enzimáticas a diferentes pH, usando curvas de calibración (A 405 nm vs. nmol) para interpolar la absorbancia de grupos p-nitrofenol o p-nitroanilina liberados por la hidrólisis de sustratos sintéticos; se utilizaron también sustratos 2-naftilamídicos y 2-naftólicos para determinar esterasas, peptidasas, fosfomonoesterasas y glicosidasas. Se demostró que fosfohidrolasas, glicosidasas y peptidasas están presentes en la FSPA, destacándose la β-NAG (0,55 μmol/h/mg, pH 5,5) y la cistein proteasa (0,4 μmol/h/mg, pH 5,5) como las actividades más elevadas, señalando la importancia funcional de la actividad glicosídica y peptídica en este parásito, las cuales están probablemente relacionadas con su hábitat y su necesidad de degradación de secreciones pulmonares. Estos resultados representan los primeros estudios enzimáticos registrados en vermes adultos de un aislado venezolano de Paragonimus sp. obtenidos del reservorio Didelphis marsupialis.

Paragonimus sp. is a trematode that causes chronic inflammation of the lung in carnivorous mammals and humans, which constitute a public health problem in Asian and Latin American countries. Trematodes have enzymes that facilitate their penetration and migration through different host organs to ensure their life cycle. To evaluate the enzymatic diversity of the soluble fraction (FSPA, 100,000 g) of a Venezuelan isolate of Paragonimus sp. adult worms, several enzyme determinations were conducted at different pH. The activities of enzymes releasing p-nitrophenol or p-nitroanilina from the corresponding dye-related synthetic peptides were assessed by interpolating absorbance (A 405 nm) values in the corresponding calibration curve (A 405 nm vs. nmol); on the other hand, absorbances of 2-naphtylamine and 2-naphtols released from another series of synthetic substrates were read at different wavelengths between 450 nm and 620 nm to assess for the activity of the corresponding hydrolases. Phosphohydrolase, glycosidase and peptidase activities were detected in FSPA, β-N-acetyl-β-D-glucosaminidase (0.55 μmol/h/mg, pH 5.5) and cystein protease (0.4 μmol/h/mg, pH 5.5) being higher than all the other detected activities. These activities are probably related to the adult worm habitat and its need for glycan and peptide degradation of lung secretions. These results represent the first enzymatic study done with a Venezuelan isolate of adult Paragonimus sp. worms collected from the common reservoir Didelphis marsupialis.

Objetivo: Determinar seropositividad para Toxoplasma gondii y Trypanosoma cruzi en embarazadas, Métodos: Estudio analítico transversal realizado en 678 gestantes. Para la detección de anticuerpos anti-Toxoplasma se utilizó ELISA para la captura de IgM, IgG y avidez de IgG. Para T. cruzi se realizó ELISA IgG y hemaglutinación indirecta. Ambiente: Consulta Prenatal del Hospital Universitario de Caracas. Resultados: El mayor número de pacientes se ubicó en el grupo etario 16 - 20 años, 42 % cursaba su primer embarazo, 25 % el segundo y 33 % tenía 3 o más. El 39 % se encontraba en el primer trimestre del embarazo, 43 % en el segundo y 18 % en el tercero. El despistaje para T. cruzi no mostró ninguna persona reactiva. Se presentó infección toxoplásmica por ELISA IgG en 38 % de las embarazadas de las cuales 10 pudieran corresponder a infecciones recientes por tener IgM positiva o baja avidez de anticuerpos específicos, 8 de ellas se encontraban en el primero o segundo trimestre del embarazo. Una segunda serología en 54 mujeres no reveló seroconversión. Conclusiones: La seropositividad para toxoplasmosis fue alta y detectó algunas embarazadas con infección reciente encontrándose la mayoría en los dos primeros trimestres, cuando hay riesgo de malformaciones congénitas. La combinación de estas técnicas en toxoplasmosis permite estimar tiempo de evolución y su aplicación en consultas prenatales permitiría detectar infecciones recientes para tratamiento oportuno. Es igualmente importante insistir en la obligatoriedad del diagnóstico de enfermedad de Chagas por ser transmisible al feto y encontrarse Venezuela entre los países endémicos.

Objective: To determine seropositivity for Toxoplasma gondii and Trypanosoma cruzi in pregnant women. Methods: A cross-sectional analytical study was conducted at 678 pregnant women. ELISA was used for the detection of anti-Toxoplasma antibodies IgM, IgG and IgG avidity. For T. cruzi IgG ELISA was performed and Indirect Hemagglutination Test. Setting: Prenatal care at the Hospital Universitario de Caracas. Results: The highest number of patients was located in the age group 16 to 20 years, 42 % was in her first pregnancy, 25 % the second and 33 % had 3 or more. The 39 % was in the first trimester, 43 % in the second and 18 % in the third. The screening for T. cruzi showed no reactive person. Toxoplasmic infection was presented by IgG ELISA in 38 % of pregnant women of which 10 might be due to recent infections by having a positive IgM or low avidity of specific antibodies, 8 of them were in the first or second trimester of pregnancy. A second serology in 54 women did not show seroconversion. Conclusions: Toxoplasmosis seropositivity was high and detected some pregnant women with recent infection in the first two quarters, when there is risk of congenital malformations. The combination of these techniques in Toxoplasmosis can estimate time of evolution and its application in prenatal consultations would detect recent infections. It is equally important to emphasize the obligation of the diagnosis of Chagas’ disease which can be transmitted to the fetus and also because Venezuela is an endemic country.

La Fasciolosis humana tiene baja frecuencia en Venezuela; sin embargo, el Municipio Mara es una región altamente endémica para fasciolosis bovina y no existen estudios sobre esta infección parasitaria en humanos. Con el propósito de determinar la prevalencia y factores asociados a la fasciolosis humana en el municipio Mara del estado Zulia, se recolectaron un total de 51 muestras de sangre y de heces. Los sueros se procesaron mediante la técnica de ELISA y “Western blot” (WB) con antígenos excreción-secreción de Fasciola hepatica (AFhES). A los sueros que resultaron positivos se les realizó ELISA IgG anti Toxocara spp, Toxoplasma gondii y cisticerosis. Las muestras de heces se concentraron mediante las técnicas de Ritchie y sedimentación rápida. Dos sueros (3,9%) fueron positivos a la técnica de ELISA AFhES; estos no reconocieron las moléculas específicas del WB-AFhES, detectadas por sueros de pacientes con infección absolutamente demostrada. Ambos individuos resultaron negativos a IgG anti Toxocara spp, Toxoplasma gondii y cisticerosis, así como también a parásitos intestinales. La prevalencia general de las parasitosis intestinales fue de 52,9% (27/51), siendo más frecuente los protozoarios que los helmintos. No se encontraron huevos de F. hepatica. Los dos individuos positivos a ELISA AFhES tenían en común trabajar en el corte de pasto fresco. Los resultados obtenidos sugieren que la población ha estado en contacto con F. hepatica, en ausencia de una infección activa por la falta de reconocimiento de las moléculas específicas del WB-AFhES y la ausencia de huevos en las heces. La fasciolosis humana tiene una baja frecuencia en Venezuela, razón por la cual no es sospechada su presencia, existiendo poco conocimiento de esta infección por el personal de salud y la población general.

In Venezuela, human Fasciolosis shows a low frequency. However, Mara Municipality is a highly endemic region for bovine fasciolosis and there are no reports of this parasite infection in humans. To determine the prevalence and associated factors to human fasciolosis in Mara municipality - Zulia state, a total of 51 blood and stool samples were collected. Serums were tested by ELISA and Western Blot (WB) assays, with excretion-secretion antigens of Fasciola hepatica (AFhES). The serum samples that resulted positive by these assays were tested by ELISA IgG anti Toxocara sp, Toxoplasma gondii and cysticerosis. Stool samples were concentrated by the Ritchie and rapid sedimentation techniques. Two serum samples were reactive to ELISA AFhES (3.9%) and these did not recognize the specific molecules of WB-AFhES detected by serum from patients with an absolutely demonstrated infection. Both participants were not positive to IgG anti Toxocara sp, Toxoplasma gondii, cysticerosis, and stool samples of these were negative to intestinal parasites. The general prevalence of intestinal parasites was 52.9% (27/51), being protozoa more frequent than helminthes. No Fasciola eggs were found. The two positives participants had in common that both had worked as fresh pasture cutters. These results suggest that the population had been in contact with F. hepatica, with no active infection because of the lack of specific molecules recognition and the absence of eggs in stool samples. Human fasciolosis has a low frequency in Venezuela and is underestimated and underrecognized by health workers and the general population.

Introducción: La Enfermedad de Chagas (ECh) usualmente es transmitida al hombre por la penetración cutánea de parásitos contenidos en las heces de vectores hematófagos conocidos como chipos. Sin embargo existen otros mecanismos de transmisión. Se presenta el primer caso diagnosticado del brote de ECh agudo de transmisión oral, ocurrido en diciembre 2007 en una escuela de Caracas. Caso clínico: Escolar de nueve años, femenino procedente de Caracas, hospitalizada con fiebre diaria 39-40°C y escalofríos de tres semanas de evolución, decaimiento, mareos, vómitos, astenia, mialgias, adenopatías cervicales, hepatomegalia, edema facial y en miembros inferiores. Los exámenes de laboratorio mostraron linfomonocitosis, serologías negativas para mononucleosis y dengue. En el frotis sanguíneo para el despistaje de malaria se encontró un tripomastigote de Trypanosoma cruzi. ELISA-IgM, ELISA-IgG, hemaglutinación indirecta, reacción en cadena de la polimerasa, cultivo e inoculación en ratones, fueron positivos para ECh. A los pocos días se detectaron casos similares y se realizó el vínculo epidemiológico que permitió el reconocimiento de una epidemia urbana de ECh de transmisión oral. La paciente recibió nifurtimox y evolucionó satisfactoriamente. Discusión: En la forma oral de transmisión de la ECh no existe signo de puerta de entrada, las manifestaciones clínicas, como la fiebre alta y prolongada y el edema, suelen ser comunes a otras patologías. En pacientes con fiebre de origen desconocido debe incluirse el frotis sanguíneo y la detección de IgM e IgG específicas para ECh como parte del plan diagnóstico. Conclusión: Se describe en forma pormenorizada el primer caso, considerado caso índice del brote de Chagas agudo adquirido por ingestión de alimentos en un colegio del municipio de Chacao en Caracas.

Introduction: Chagas disease (ChD) is usually transmitted to man by cutaneous penetration of parasites contained in the feces of haematofagous vectors known as “kissing bugs or chipos”. However, other transmission mechanisms may occur. Herein, we report the first diagnosed case of an epidemic outbreak of acute oral transmitted ChD occurred in December 2007 in a school of Caracas. Clinical case: A 9 year old schoolgirl, coming from Caracas, was hospitalized with daily fever 39-40°C and chills of three weeks duration, sickness, vomitting, astenia, mialgias, cervical adenopathies, hepatomegaly, facial and inferior members edema. The laboratory tests showed lymphomonocytosis, negative serologies for mononucleosis and dengue. In the blood smear done to rule out malaria, tripomastigote of Trypanosoma cruzi was found. ELISA-IgM, ELISA-IgG, indirect hemaglutination, polymerase chain reaction, culture and mice inoculation were all positive for ChD. Few days after, similar cases were detected and it was carried out the epidemiological link that allowed the recognition of an urban outbreak of ChD of oral transmission. The patient evolved satisfactorily after being treated with nifurtimox. Discussion: In the oral form of transmission of the ChD, signs of entrance do not exist, the clinical manifestations as high and prolonged fever and edema are common to other pathologies. In patients with fever of unknown origin, blood smear as well as search for specific IgM and IgG for ChD should be included as part of the diagnosis. Conclusion: The first case is described in detailed form, considered index case of the outbreak of acute Chagas acquired by food ingestion in a school of Chacao's county in Caracas.

En este trabajo se presenta la propuesta metodológica para llevar a cabo la transformación curricular en la Escuela de Medicina “Luis Razetti, orientada a la elaboración de un currículo integral, flexible, centrado en el estudiante y bajo el enfoque de competencia, que favorezca un proceso educativo capaz de responder a las necesidades integrales de salud de nuestra población. La transformación curricular se configura como la respuesta de la institución y de su comunidad académica frente a los desafíos crecientes que plantean los cambios culturales, políticos, socioeconómicos, laborales y educacionales del mundo y de la sociedad país en que vivimos. Se propone diseñar un currículo dirigido al desarrollo de la Competencia Médica para la Atención Primaria en Salud (APS) utilizando para ello la metodología de la Educación Basada en Resultados. Se plantea el uso del Modelo Socio-Cognitivo como teoría educativa y de diseño curricular, y el Modelo de los Tres Círculos (M3C) como modelo para el desarrollo de la competencia médica. Este trabajo representa el producto de la labor conjunta de la Comisión de Currículo y del Consejo de la Escuela de Medicina “Luis Razetti”, en el período comprendido de enero a junio del año 2007, incluyendo los resultados correspondientes a la primera etapa del plan estratégico de gestión de la Comisión.

This paper presents a methodological proposal for a curricular change in the “Luis Razetti” School of Medicine, oriented towards an integrated, student centred, flexible, competency-based curriculum designed to promote an educational process responsive to the health needs of our population. This curricular change represents a response of the academic community and the institution to challenges presented by cultural, political, socioeconomic and educational changes occurring in the world and in our society. The curricular proposal will be directed towards the development of medical competency for primary health care (PHC) by means of the methodology known as Outcome Based Education, using the Three Circle Model to define the outcomes of the educational process and the Socio-Cognitive educational model as the basis for curricular design. This paper summarizes the work of the Curricular Committee and the Council of the “Luis Razetti” Medical School during the first half of 2007, corresponding to the first stage of the Curricular Committee’s strategic plan.

La Paragonimiasis es una zoonosis parasitaria de diversos animales silvestres o domésticos y del hombre, causada por especies de tremátodes del género Paragonimus siendo el Paragonimus westermani el que más infecta al hombre. El humano se infecta al ingerir crustáceos de agua dulce parasitados (cangrejos de río) crudos o insuficientemente cocidos. El objetivo de este trabajo es describir el caso de un preescolar masculino de 3 años y medio de edad, natural y procedente del estado Guárico quien vivió un año en zona costera del Ecuador (Provincia Manabí) donde consumió alimentos de la zona como ceviche. Consultó por dificultad respiratoria y durante la hospitalización se evidenció hepatomegalia y presencia de nódulos subcutáneos en espalda. La Tomografía Axial computarizada (TAC) de tórax reveló importante infiltrado a nivel de ambas bases pulmonares a predominio del lado derecho con derrame y engrosamiento pleural. Por la clínica, las imágenes radiológicas, la eosinofilia (47% con contaje absoluto de eosinófilos (CAE) 6.862/mm³) y el antecedente de ingesta de cangrejos crudos 6 meses antes, se sugirió descartar paragonimiasis pulmonar. En un estudio seriado de muestras de sueros se evidenció la presencia de anticuerpos específicos anti-Paragonimus por ELISA y Western blot, sin embargo no se encontraron huevos del parásito en heces o en esputo. Se indicó tratamiento con praziquantel 25 mg/kg de peso 3 tomas al día durante 3 días con lo cual desapareció la sintomatología, mejoraron las imágenes radiológicas y disminuyó el contaje de eosinófilos.

Paragonimiasis is a zoonosis affecting wild and domestic animals and human beings, caused by species of trematodes of the genus Paragonimus. Humans become infected after ingestion of raw or poorly cooked fresh water crustaceans. The aim of the present work is the description of a case of a 3-years old child, coming from Guárico State in Venezuela with a year of residence in the seashore of the Provincia Manabí in Ecuador, where he ate crabs in “ceviche”. During hospitalization, he presented respiratory distress, hepatomegaly and nodules in the back. The thorax cat scan showed heavy infiltrate in both pulmonary bases and pleural compromise. Based on clinic, radiological images, an eosinophilia of 47% (Eosinophils absolute count (EAC) 6.682/mm³) and the antecedent of raw crabs ingestion, pulmonary paragonimiasis was diagnosed. Paragonimus eggs were not found in sputum and feces. ELISA with crude Paragonimus antigen was positive and Western blot revealed recognition of specific molecules. After treatment for three days with Praziquantel at a daily dose of 25 mg/kg body weight divided into three intakes, the sintomatology disappeared and radiological images and number of eosinophils diminished considerably.