Diarrea crónica por Lamblia intestinalis en un adulto / (Chronic diarrhea by Lamblia intestinalis in an adult)

ResumenSe presenta un caso de inmunodeficiencia común variable en un paciente masculino, joven con larga historia (9 años) de procesos infecciosos gastrointestinales y respiratorios recurrentes; a pesar de los diferentes esquemas terapéuticos, con evidencia diagnóstica de niveles bajos de inmunoglobulinas de las clases IgG, IgM e IgA; se pretende comparar su evolución a partir de su historia clínica y los resultados de sus exámenes complementarios, con la bibliografía revisada. La inmunodeficiencia común variable explica un déficit primario de IgG (al menos 2 desviaciones estándar por debajo de los valores de referencia para su edad), al menos otra de las Ig (IgA o IgM) y una reducción o ausencia de producción de anticuerpos. Esta entidad se considera poco frecuente en términos de incidencia, aunque cursa muchas veces inadvertida por el predominio de sus efectos. Clínicamente, se manifiesta por la presencia de infecciones recurrentes con preponderancia de las respiratorias y gastrointestinales. Desde el punto de vista etiológico, su génesis es controversial, pero se describen niveles bajos de inmunoglobulinas y una reducción o ausencia de producción de anticuerpos.

AbstractWe present a variable common immunodeficiency case in a young male patient with a long history (9 years) of recurrent gastrointestinal and respiratory infectious processes, despite the different therapeutic schemes, with diagnostic evidence of low levels of IgG, IgM And IgA; aiming to make a comparison of its evolution in function of its clinical history and the results of its complementary examinations, with the bibliography reviewed. Variablecommon immunodeficiency explains a primary IgG deficit (at least 2 standard deviations below the reference values for his age) and at least one other Ig (IgA or IgM) and a reduction or absence of antibody production. This entity is considered infrequent in terms of incidence, although it is often inadvertent due to the predominance of its effects. Clinically it is manifested by the presence of recurrent infections with preponderance of the respiratory and gastrointestinal. From an aetiological point of view, its genesis is controversial, but low levels of immunoglobulins and a reduction or absence of antibody production are all described.

Infecciones maláricas en individuos asintomáticos en la población indígena Jivi, Amazonas, Venezuela / Asymptomatic malaria infection in the indigenous Jivi population, Amazonas state, Venezuela

Se evaluó la presencia de infecciones maláricas en individuos asintomáticos en la población Jivi de Puente Parhueña. El estudio fue de tipo prospectivo en tres momentos. El diagnóstico parasitológico se realizó mediante el examen convencional de gota gruesa y extendido (GGE) y la reacción en cadena de la polimerasa (PCR). El diagnóstico por microscopia indicó 2% (5/261) de láminas positivas en Abril, 1% (3/274) en Septiembre y 4% (5/135) en Diciembre. La PCR para Plasmodium spp., fue 46% (26/57) en abril, 49% (28/57) en Septiembre y 35% (20/57) en Diciembre. En los tres momentos predominó la presencia de P. vivax. La prueba de ELISA demostró 72% (41/57) seroreactivos en Abril, 53% (30/57) en Septiembre y 60% (34/57) en Diciembre. En Puente Parhueña habitan individuos con infecciones maláricas asintomáticos, con persistencia de anticuerpos antimalaricos, que probablemente representan un reservorio de gametocitos dentro de la comunidad.

The study was carried out to determine the present malaria infection in the asymptomatic Jivi people of Puente Parhueña. The study was prospective over three periods of time. The parasitological diagnoses were from thick and thin blood smears (GGE) and polymerase chain reaction (PCR). The antibody search was performed by ELISA. Microscopy of the slides detected the following positive results: 2% (2/261) April, 1% (3/274) September and 4% (5/135) December. Detection of Plasmodium by PCR was 46% (26/57) in April, 49% (28/57) in September y 35% (20/57) in December. Plasmodium vivax infected individuals predominated during these 3 times. Positives for ELISA were 72% (41/57) in April, 53% (30/57) September and 60% (34/57) December. The study demonstrated that people living in Puente Parhueña presented asymptomatic malaria infection with malaria antibodies persistence which likely represents a gametocyte potential reservoir for infection among the population.

Desenvolvimento e caracterização de uma vacina antiesquistossomose composta pela proteína Sm14 de Schistosoma mansoni utilizando a subunidade B da toxina colérica (CTB) como adjuvante / Development and characterization of an antischistosomiasis vaccine composed by Sm14 protein, from Schistosoma mansoni, using the B subunit of cholera toxin (CTB) as adjuvant

Introdução: o desenvolvimento de uma vacina contra a esquistossomose será um importante avanço no controle desta doença crônica e muitas vezes debilitante, afetando milhões de pessoas em todo o mundo. Neste trabalho, descrevemos o uso da subunidade B da toxina colérica (CTB) geneticamente fusionada com Sm14 - uma proteína ligadora de ácidos graxos de Schistosoma mansoni - como uma tentativa de desenvolver uma vacina antiesquistossomose. Métodos: proteínas recombinantes foram expressas em um sistema procariótico, purificadas por diferentes métodos cromatográficos e caracterizadas tanto por métodos imunoquímicos como por métodos espectroscópicos. Experimentos de imunização foram realizados em camundongos fêmeas, da linhagem BALB/c e a eficácia da vacina determinada através da análise da carga parasitária após o desafio com cercárias de S. mansoni e através da análise histopatológica das reações granulomatosas ao redor dos ovos aprisionados no tecido hepático dos camundongos. Resultados: a administração subcutânea de Sm14 reduziu em 27 por cento a carga parasitária nos animais vacinados. Por outro lado, a vacinação intranasal apenas demonstrou uma redução estatisticamente significativa quando CTB esteve presente na formulação...

Human chronic chagasic cardiopathy: participation of parasite antigens, subsets of lymphocytes, cytokines and microvascular abnormalities

This article tries to demonstrate by new pathological findings (with the use of immunohistochemical technique and confocal laser microscopy) that chronic chagasic cardiomyopathy is a result of multiple factors involving myocarditis, immunodepression, severe fibrosis and microvessels dilatation and that all of these alterations are probably directly related with the presence of Trypanosoma cruzi parasites in the host associated with inadequate immunological response of the host.

The art of parasite survival

Parasites develop and survive in an environment which is often hostile to them. When facing aggressive conditions parasites are able to use various and complex strategies. Echinococcus granulosus, Toxocara canis, Pneumocystis carinii, Entamoeba or Toxoplasma gandii are able to seclude from the environment when stressed by surrounding (immunologic or non-immunologic) agressive factors. Specific antigens which exert a functional activity during a short period of time appear to be concealed from the immune attack at this crucial moment. This is the case for rhoptry or dense granule antigens of Plasmodium or Toxoplasma sporozoa involved in the formation of the parasitophorous vacuole which are released in a space perfectly isolated from the outside and therefore from antibodies. Some parasites like Schistosoma mansoni or Trypanosoma brucei reveal an amazing opportunistic behavior when they use cytokines of host origin induced by the infectious process for their own development. Leishmania, Toxoplasma and Trypanosoma cruzi are able to invade immunologically competent macrophages and to avoid the triggering of killing mechanisms of these cells. Parasites also take advantage of the genetic restriction of the immune response and it has been observed for Plasmodia that some high molecular weight antigens are unable to induce an immune response in particular strains of mice. Parasite receptors involved in the invasion of host cells by parasites can function in the presence of antibodies which can explain the failure of vaccination attempts targeting this type of molecules. Among the mechanisms developed by parasites to resist to drugs it appears that transmembrane transporters described in many protozoa or helminth parasites could play a role. Moreover, the description of parasite-specific enzymes able to protect them against the damaging effects of oxygen radicals suggests that parasites are potentially able to develop a resistance phenomenon against drugs acting via an oxidative burst

Transmammary transmission of parasites and parasitic antibodies in human milk

To search about transmammary transmission of parasites and the presenee of parasitic: antibodies in breast milk, 60 lactating women were served for examination of l-current stool samples to detect any parasitic infection, 2-serum samples for assaying IgGAb against 5 parasites by ELISA and IFAT; 3-one colostrum sample followed by milk sample monthly for 5 months for detection of antiparasitic antibodies and their persistenee, and search for parasitic larvae or Toxoplasma tachyzoites. The results revealed that all colostrum and milk samples [360] were free from parasitic infection current stool samples [60] showed Ascaris in 2 cases, Ancylostoma in another 2 and Strongyloides stercoralis in one case. Antiparasitic: IgG Ab were detected by ELISA in the serum against Fasciola hepatica, Strongyloides stercoralis, Trichinella spiralis, Giardia lamblia and Toxoplasma gondii in 11.7, 6.7, 1.7, 26.7 and 16.7% of the cases, while they were in 8.3, 5, 1.7, 23.3 and 15% of the colostrum samples respectively. The IFAT showed approximately the same results. There was persistence of milk antibodies secretion which declined with the progress of lactation with variance between cases as regard the same antiparasitic antibodies and between different antiparasitic antibodies. It was concluded that there is no potential mood for transmammary passage of parasites and the few detected cases by some authors are only sporadic and rare occasion and even if this occurs colostrum and milk specially during the early months of lactation contain antiparasitic antibodies that can protect breast fed infant from parasitic infection

Application of biotechnology to the study of molluscan hosts of animal parasites.

The intimate and complex relationship that exists between man and mollusc makes the group an ideal target for the application of biotechnology. The paper discusses and reviews the application of both the conventional and new molecular techniques to the study of the molluscan hosts of animal parasites. The remarkable advances in molluscan biology which have occurred during the past two decades as a consequence of conventional technological methods are noted and applications pertinent to problems in Southeast Asia are cited. Applications of new biotechniques, including those of molecular biology, to problems of the host-parasite interaction are discussed. Examples of how the new biotechnology may resolve present and future problems in applied malacology are presented.

Inmunoparasitologia: origem, estado actual y perspectivas / Immunoparasitology: origin, current status and perspectives

Se hace un repaso de los principales adelantos logrados por la inmunoparasitología en su corta existencia. Luego de señalar los obstáculos que deben superarse para obtener antígenos adecuados, se explican brevemente las principales aplicaciones práticas de la nueva disciplina, a saber: inmunodiagnóstico de parasitosis, encuestas epidemiológicas, evaluación de la curación de las parasitosis despúes del tratamiento, inmunopatología de enfermedades parasitarias y perspectivas de la elaboración de vacunas antiparasitarias, principalmente contra el paludismo causado por P. falciparum. La descripción de estos adelantos está basada en la experiencia del autor y en una revisión bibliográfica. Se destaca la rapidez del avance de la inmunoparasitología en años recientes y la orientación práctica de muchas investigaciones en este campo