Revisión de los aspectos biológicos y diagnósticos del Trypanosoma (Herpetosoma) rangeli

Abstract

Resumen Esta revisión tiene tres objetivos básicos: a) estimular aún más la investigación de esta prevalente infección humana. b) examinar el arsenal de técnicas diagnósticas disponíbles al momento y, las nuevas pruebas descritas recientemente. c) enfatizar el significado que tiene, el parasitismo por el Trypanosoma (Herpetosoma) rangeli, en las áreas endémicas de la Enfermedad de Chagas distribuidas en las Américas Central y del Sur. Trypanosoma rangeli y Trypanosoma cruzi son parásitos que circulan superponiéndose en muchas áreas de Latinoamérica utilizando prácticamente los mismos triatominos vectores. Una vasta gama de especies de mamíferos han sido encontradas infectadas naturalmente con T. rangeli en diversos países. Se revisa la biología del parasitismo y el ciclo biológico del tripanosoma haciendo énfasis en este último. Infecciones crónicas por T. rangeli en el hombre pueden, serológicamente, ser confundidas con las del T. cruzi. Ambas especies presentan antígenos comunes que provocan las conocidas reacciones serológicas cruzadas. Desafortunadamente, no conocemos la real distribución de las infecciones por el T. rangeli en la mayoría de las áreas mencionadas. Nuevos estudios epidemiológicos son necesarios, para examinar el problema de las infecciones humanas mixtas, por estos tripanosomas. Palabras-claves: Trypanosoma (Herpetosoma) rangeli. Biología. Epidemiología. Diagnóstico. 207Revisión de los aspectos biológicos y diagnósticos del Trypanosoma (Herpetosoma) rangeli ARTIGO DE REVISÃOIdentificación. diferenciación. Abstract This review has three objectives: a) To stimulate further research of this prevalent human infection b) to examine the progress of current diagnostic techniques and c) to emphasise the significance of the flagellate parasite Trypanosoma (Herpetosoma) rangeli in Chagas' Disease endemic areas of South and Central America. Both Trypanosoma rangeli and Trypanosoma cruzi overlap in many of the areas of Latin America utilising the same triatomine vectors. Also a vast range of mammalian species have been found naturally infected with T. rangeli . The biology of the parasitism of T. rangeli is revised and emphasis is given regarding its biological cycle. T. cruzi and T. rangeli share common antigens and cross react serologically. Human infection in the chronic phase may be misdiagnosed as T. cruzi infection. Conventional and modern diagnostic and identification methods are discussed. Unfortunately we do not know the real distribution of T. rangeli infections in most areas and epidemiological studies to examine concomitant dual infections deserve further investigation.

Susceptibilidad de diferentes especies de Rhodnius (Hemiptera, Reduviidae, Triatominae) a una cepa brasileña de Trypanosoma rangeli (SC58/KP1-)

“…rangeli is considered to be pathogenic to its invertebrate hosts, being responsible for triatomine death (1,6,41,42). It is known that several aspects of the physiology of the triatomines are altered during infection by T. rangeli, including reduced immune responses, anti-hemostatic activity of the salivary glands, and behavioral changes such as molting delays, changes in the movements of the insects, decreased reproductive performance and increased mortality (29,43,44).…”

“…The most notable biological characteristic of T. rangeli in its invertebrate hosts is the passage of parasites from the intestine into the hemolymph and then to the insect salivary glands, where the protozoan develops infective metacyclic trypomastigotes. Then, they become infective to the vertebrate host through the bite of the insect vector (1)(2)(3). Rhodnius specimens are particularly susceptible to infection with T. rangeli; 13 of 19 Rhodnius species were reported to be infected with this parasite (4,5).…”

Trypanosoma (Herpetosoma) rangeli Tejera, 1920: an updated review

“…Herpetosoma sub-genus species usually have specific hosts; however, T. rangeli presents a wide range of vertebrate reservoirs distributed among 5 orders: Edentata, Marsupialia, Carnivora, Rodentia and Primates (D'Alessandro 1976, D'Alessandro-Bacigalupo & GoreSaravia, 1992, Cuba Cuba 1998. Different species, including rats, mice, hamsters, rabbits, dogs, guinea-pigs, bat and primates have all been experimentally infected with T. rangeli.…”

“…It has been observed that the triatomids (particularly from the Rhodnius genus) are susceptible to T. rangeli strains having the same geographical origin (Cuba Cuba et al 1972, Cuba Cuba 1998, D'Alessandro 1976, D'Alessandro-Bacigalupo & Gore-Saravia 1992, Machado et al 2001). Several T. rangeli strains have shown variable behaviour in different Rhodnius species; for example, strains from Colombia and Costa Rica do not produce metacyclic tripomastigotes in R. pallescens or R. ecuadoriensis.…”

Enzootic transmission of Trypanosoma cruzi and T. rangeli in the Federal District of Brazil

“…The criteria of inclusion were also accessibility and entrance permission by the government and farmers. Classical parasitological 7 and molecular techniques (see below) were used for detecting natural infection by trypanosomatids.…”