PCR-RFLP analyses of Leishmania species causing cutaneous and mucocutaneous leishmaniasis revealed distribution of genetically complex strains with hybrid and mito-nuclear discordance in Ecuador.

PCR-Restriction Fragment Length Polymorphism (RFLP) analyses targeting multiple nuclear genes were established for the simple and practical identification of Leishmania species without using expensive equipment. This method was applied to 92 clinical samples collected at 33 sites in 14 provinces of Ecuador, which have been identified at the species level by the kinetoplast cytochrome b (cyt b) gene sequence analysis, and the results obtained by the two analyses were compared. Although most results corresponded between the two analyses, PCR-RFLP analyses revealed distribution of hybrid strains between Leishmania (Viannia) guyanensis and L. (V.) braziliensis and between L. (V.) guyanensis and L. (V.) panamensis, of which the latter was firstly identified in Ecuador. Moreover, unexpected parasite strains having the kinetoplast cyt b gene of L. (V.) braziliensis and nuclear genes of L. (V.) guyanensis, L. (V.) panamensis, or a hybrid between L. (V.) guyanensis and L. (V.) panamensis were identified. This is the first report of the distribution of a protozoan parasite having mismatches between kinetoplast and nuclear genes, known as mito-nuclear discordance. The result demonstrated that genetically complex Leishmania strains are present in Ecuador. Since genetic exchanges such as hybrid formation were suggested to cause higher pathogenicity in Leishmania and may be transmitted by more species of sand flies, further country-wide epidemiological studies on clinical symptoms, as well as transmissible vectors, will be necessary.

Geographic Distribution of Leishmania Species in Ecuador Based on the Cytochrome B Gene Sequence Analysis.

A countrywide epidemiological study was performed to elucidate the current geographic distribution of causative species of cutaneous leishmaniasis (CL) in Ecuador by using FTA card-spotted samples and smear slides as DNA sources. Putative Leishmania in 165 samples collected from patients with CL in 16 provinces of Ecuador were examined at the species level based on the cytochrome b gene sequence analysis. Of these, 125 samples were successfully identified as Leishmania (Viannia) guyanensis, L. (V.) braziliensis, L. (V.) naiffi, L. (V.) lainsoni, and L. (Leishmania) mexicana. Two dominant species, L. (V.) guyanensis and L. (V.) braziliensis, were widely distributed in Pacific coast subtropical and Amazonian tropical areas, respectively. Recently reported L. (V.) naiffi and L. (V.) lainsoni were identified in Amazonian areas, and L. (L.) mexicana was identified in an Andean highland area. Importantly, the present study demonstrated that cases of L. (V.) braziliensis infection are increasing in Pacific coast areas.

Detección de anticuerpos de entamoeba histolytica por el método de Elisa en la costa ecuatoriana: 1999 / Detection of Hystolitic entamoeba antibodies by the Elisa method in ecuadorian coast: 1999

Este trabajo enfoca el estudio seroepidemiológico de la Amebiosis en la región de la costa ecuatoriana; se utilizó un método de ensayo inmunoenzimático en fase sólida con equipo semiautomatizado ELISA con el reactivo marca Diamedix. Para estandarizar este método se analizaron 249 sueros de pacientes provenientes de la costa ecuatoriana, (provincias de: Manabí, Guayas, Los Ríos y El Oro), con una tasa de positividad de 0.19 por ciento. De las muestras provenientes, 68 correspondiente a mujeres y el 32 por ciento a hombres cuyas edades varían entre menores de un año hasta mayores de 55 años. El riesgo relativo de casos positivos establece un índice de 1.58 (0.90 2.75) y su proporción de frecuencia es de 1.75 (0.85

This work focuses the seroepidemiologic study of amebiosis in the ecuadorian coast; through a method of inmunenzimatic essay in solid phase with ELISA semiautomatized equipment with Diamedix (reactive). We analized 249 serum samples from patients of Manabi, Guayas, Los Rios and El Oro, with a positive range of 68 percent of women and 32 percent of men with ages between less than a year and more than 55 years. Relative risk of positive cases was 1.58 (0.9 2.75) and its frequency proportion of 1.75 (0.85