Impacto de la deficiencia de glucosa-6-fosfato deshidrogenasa en individuos de zonas endémicas de malaria

Glucose-6-phosphate dehydrogenase (G6PD) is a cytoplasmic enzyme that is essential for a cell’s capacity to withstand oxidant stress generated by molecules or reactive oxygen species (ROS) in human cells that could damage the integrity of cellular structures. G6PD deficiency (G6PDd) is one of the most common hereditary hemolytic disorders affecting about 400 million people worldwide. Its distribution and major frequency occurs mainly in tropical and subtropical regions of the world where malaria is or has been endemic. Several studies have demonstrated a potential protective effect against severe forms of malaria; conversely, individuals with G6PDd show complications and adverse clinical manifestations such as hemolytic anemia after treatment with antimalarial drugs such as primaquine and other 8-aminoquinolines (8AQ) drugs. Despite the evidence of the potential negative effects in developing countries endemic for malaria there is no information or a limited number of studies aimed to investigate the prevalence and frequency of G6PD deficient variants that supports treating policies in these vulnerable populations suffering of malaria.Revista Portal de Ciencias, No. 8, June 2015: 45-58La glucosa-6-fosfato deshidrogenasa (G6PD) es una enzima citoplasmática esencial para contrarrestar el estrés oxidativo generado por moléculas o especies reactivas de oxígeno (ROS) en las células humanas, las que podrían dañar su integridad. La deficiencia de glucosa-6-fosfato deshidrogenasa (G6PDd) constituye uno de los desórdenes hemolíticos hereditarios más comunes, afectando a cerca de 400 millones de personas a nivel mundial.Su distribución y mayor frecuencia ocurre principalmente en regiones tropicales y subtropicales del mundo en donde la malaria es o ha sido endémica. Diversos estudios han demostrado un potencial efecto protector de la G6PDd contra formas graves de malaria; asimismo, en estos individuos se han observado complicaciones y manifestaciones clínicas adversas como la anemia hemolítica, después de recibir tratamiento con drogas antimaláricas como la primaquina y otras drogas de la familia de las 8-aminoquinolinas (8AQ). A pesar de la evidencia de sus efectos negativos potenciales, en muchos países en vías de desarrollo endémicos de malaria existen pocos estudios o un vacío absoluto de información sobre la prevalencia y frecuencia de alelos deficientes del gen de la G6PD que apoyen los esquemas de tratamiento dirigidos a estas poblaciones vulnerables que padecen de malaria.Revista Portal de Ciencias, No. 8, junio 2015: 45-5

High Endemicity of Soil-Transmitted Helminths in a Population Frequently Exposed to Albendazole but No Evidence of Antiparasitic Resistance

Soil-transmitted helminths (STHs) are gastrointestinal parasites widely distributed in tropical and subtropical areas. Mass drug administration (MDA) of benzimidazoles (BZ) is the most recommended for STH control. These drugs have demonstrated limited efficacy against Trichuris trichiura and the long-term use of single-dose BZ has raised concerns of the possible emergence of genetic resistance. The objective of this investigation was to determine whether genetic mutations associated with BZ resistance were present in STH species circulating in an endemic region of Honduras. Methods: A parasitological survey was performed as part of this study, the Kato–Katz technique was used to determine STH prevalence in children of La Hicaca, Honduras. A subgroup of children received anthelminthic treatment in order to recover adult parasite specimens that were analyzed through molecular biology techniques. Genetic regions containing codons 200, 198, and 167 of the β-tubulin gene of Ascaris lumbricoides and Trichuris trichiura were amplified and sequenced. Results: Stool samples were collected from 106 children. The overall STH prevalence was 75.47%, whereby T. trichiura was the most prevalent helminth (56.6%), followed by A. lumbricoides (17%), and hookworms (1.9%). Eighty-five sequences were generated for adjacent regions to codons 167, 198, and 200 of the β-tubulin gene of T. trichiura and A. lumbricoides specimens. The three codons of interest were found to be monomorphic in all the specimens. Conclusion: Although the inability to find single-nucleotide polymorphisms (SNPs) in the small sample analyzed for the present report does not exclude the possibility of their occurrence, these results suggest that, at present, Honduras’s challenges in STH control may not be related to drug resistance but to environmental conditions and/or host factors permitting reinfections.Brock University Library Open Access Publishing Fun

Enfermedad renal oculta en pacientes con rasgo drepanocítico

Sickle cell trait is usually seen as a benign condition but has been shown to cause different pathological consequences. Within these associations, one of the most important is the increased risk of chronic kidney disease in these individuals. This study aims to determine the prevalence of occult renal disease identified in people with the condition. The study was conducted in the population of the community of Ciriboya, Colón, Honduras in January 2015. With a sample of 20 people, over 18 years, which were identified with sickle cell trait in a previous research. Validated screening tool for Occult Renal Disease (SCORED) was applied in each participant, hemoglobin levels, glucose, blood pressure and proteinuria were determined, also medical history and risk factors were recorded. Data were entered and processed in the software Epi info 7. The sample included 13 women (65%) and 7 men (35%) in the age range between 19 and 83 years with an SD of 18.4, in which the prevalence of increased risk for kidney disease was found in 45 % of the study subjects. To give a special attention to people with sickle cell trait, since it is no longer considered a harmless condition, under the circumstances of the increase in pathological complications it can cause. Tracking those identified with an increased risk of kidney disease is recommended.El rasgo drepanocítico es casi siempre visto como una condición benigna pero se ha demostrado que puede causar diferentes consecuencias patológicas. Dentro de esta asociación, una de las más importantes, es el riesgo aumentado de enfermedad renal crónica en estos individuos. El presente estudio tiene como objetivo determinar la prevalencia de enfermedad renal oculta en personas identificados con rasgo drepanocítico. Se realizó un estudio descriptivo y transversal en una muestra de la población de la comunidad de Ciriboya, del departamento de Colón, Honduras en enero del año 2015. Participaron 20 personas, mayores de 18 años, las cuales fueron identificadas con rasgo drepanocítico en una investigación previa. Para calcular el riesgo se utilizó la herramienta validada de tamizaje para Enfermedad Renal Oculta (SCORED), se determinaron los niveles de hemoglobina, glucosa en ayunas, tensión arterial y proteinuria, así mismo se registraron antecedentes patológicos y factores de riesgo de cada persona. Los datos fueron ingresados y procesados en el programa Epi info 7 y el nivel de riesgo para enfermedad renal fue calculado mediante los puntajes que este instrumento establece. La muestra estudiada fue de 13 mujeres (65%) y 7 hombres (35%) en un rango de edad entre 19 y 83 años con una SD de 18.4, se encontró una prevalencia de riesgo aumentado de enfermedad renal en el 45% de los sujetos de estudio. Las personas con rasgo drepanocítico deben de recibir un seguimiento clínico especial considerando el riesgo aumentado de padecimiento de enfermedad renal en la población estudiada

Drug resistance associated genetic polymorphisms in Plasmodium falciparum and Plasmodium vivax collected in Honduras, Central America

Background: In Honduras, chloroquine and primaquine are recommended and still appear to be effective for treatment of Plasmodium falciparum and Plasmodium vivax malaria. The aim of this study was to determine the proportion of resistance associated genetic polymorphisms in P. falciparum and P. vivax collected in Honduras. Methods: Blood samples were collected from patients seeking medical attention at the Hospital Escuela in Tegucigalpa from 2004 to 2006 as well as three regional hospitals, two health centres and one regional laboratory during 2009. Single nucleotide polymorphisms in P. falciparum chloroquine resistance transporter (pfcrt), multidrug resistance 1 (pfmdr1), dihydrofolate reductase (pfdhfr) and dihydropteroate synthase (pfdhps) genes and in P. vivax multidrug resistance 1 (pvmdr1) and dihydrofolate reductase (pvdhfr) genes were detected using PCR based methods. Results: Thirty seven P. falciparum and 64 P. vivax samples were collected. All P. falciparum infections acquired in Honduras carried pfcrt, pfmdr1, pfdhps and pfdhfr alleles associated with chloroquine, amodiaquine and sulphadoxine-pyrimethamine sensitivity only. One patient with parasites acquired on a Pacific Island had pfcrt 76 T and pfmdr1 86Y alleles. That patient and a patient infected in West Africa had pfdhfr 51I, 59 R and 108 N alleles. Pvmdr1 976 F was found in 7/37 and two copies of pvmdr1 were found in 1/37 samples. Pvdhfr 57 L + 58 R was observed in 2/57 samples. Conclusion: The results indicate that P. falciparum from Honduras remain sensitive to chloroquine and sulphadoxine-pyrimethamine. This suggests that chloroquine and sulphadoxine-pyrimethamine should be efficacious for treatment of uncomplicated P. falciparum malaria, supporting current national treatment guidelines. However, genetic polymorphisms associated with chloroquine and sulphadoxine-pyrimethamine tolerance were detected in local P. vivax and imported P. falciparum infections. Continuous monitoring of the prevalence of drug resistant/tolerant P. falciparum and P. vivax is therefore essential also in Honduras.Swedish International Development Cooperation Agency, Department for research Cooperation (Sida-SAREC) [75007082/03]info:eu-repo/semantics/publishedVersio

Genetic structure of Plasmodium falciparum populations across the Honduras-Nicaragua border

Abstract Background The Caribbean coast of Central America remains an area of malaria transmission caused by Plasmodium falciparum despite the fact that morbidity has been reduced in recent years. Parasite populations in that region show interesting characteristics such as chloroquine susceptibility and low mortality rates. Genetic structure and diversity of P. falciparum populations in the Honduras-Nicaragua border were analysed in this study. Methods Seven neutral microsatellite loci were analysed in 110 P. falciparum isolates from endemic areas of Honduras (n = 77) and Nicaragua (n = 33), mostly from the border region called the Moskitia. Several analyses concerning the genetic diversity, linkage disequilibrium, population structure, molecular variance, and haplotype clustering were conducted. Results There was a low level of genetic diversity in P. falciparum populations from Honduras and Nicaragua. Expected heterozigosity (H e ) results were similarly low for both populations. A moderate differentiation was revealed by the FST index between both populations, and two putative clusters were defined through a structure analysis. The main cluster grouped most of samples from Honduras and Nicaragua, while the second cluster was smaller and included all the samples from the Siuna community in Nicaragua. This result could partially explain the stronger linkage disequilibrium (LD) in the parasite population from that country. These findings are congruent with the decreasing rates of malaria endemicity in Central America.We would like to thank Dr Udhayakumar Venkatachalam and his research team at Malaria Branch, CDC, for technical assistance and providing amplification protocols and DNA of reference clones. DNA from reference clones was also provided by Irina Jovel from Karolinska Institute, Sweden. The financial support for this work was provided by CSIC (I-COOP0071). Complementary funds were provided by Direccion de Investigacion Cientifica – UNAH.Peer Reviewe

A four-year surveillance program for detection of Plasmodium falciparum chloroquine resistance in Honduras

Countries could use the monitoring of drug resistance in malaria parasites as an effective early warning system to develop the timely response mechanisms that are required to avert the further spread of malaria. Drug resistance surveillance is essential in areas where no drug resistance has been reported, especially if neighbouring countries have previously reported resistance. Here, we present the results of a four-year surveillance program based on the sequencing of the pfcrt gene of Plasmodium falciparum populations from endemic areas of Honduras. All isolates were susceptible to chloroquine, as revealed by the pfcrt “CVMNK” genotype in codons 72-76