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Cerebral small vessel disease is a major contributor to both brain aging and cognitive decline. This study aimed to determine the prevalence of cerebral small vessel disease in a Colombian population over 40 years of age who attended a Radiology and Diagnostic Imaging service for brain MRI between October 2018 and March 2019. This was an observational, cross-sectional and analytical study of 710 adult patients over 40 years of age who attended the Radiology and Diagnostic Imaging service for a brain MRI. The analysed data were obtained from an anonymized database of the service. We studied 710 MRI scans of patients aged between 40 and 104 years. The most frequent risk factor was hypertension (36.2%). Brain abnormalities associated with cerebral small vessel disease, such as white matter hyperintensities, were seen in 56.20% of the population, and brain atrophy was observed in 12.96%. Brain disease prevalence increased with age (23.18% for those aged 55 years, 54.49% for those aged 55-64 years, 69.8% for those aged 65-74 years and 90.53% for those older than 75 years). The prevalence of cerebral small vessel disease in our population was similar to that reported in the world literature, as were the prevalence of the evaluated cardiovascular risk factors. Additionally, we identified an association between hypertension and advanced age with cerebral small vessel disease, with white matter hyperintensities being the most characteristic finding.

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Objetivo: Determinar la prevalencia y los factores asociados con el trastorno depresivo en adultos peruanos mayores de 60 años. Materiales y métodos: Se realizó un estudio observacional, analítico y transversal a partir de un análisis secundario de la Encuesta Demográfica y de Salud Familiar (ENDES) del año 2019, aplicada con un alcance nacional por el Instituto Nacional de Estadística e Informática del Perú (INEI). La muestra fue de 4174 adultos mayores. Se consideró como variable principal el padecer de trastorno depresivo (con depresión/sin depresión) y como variables independientes, edad, sexo, grado de instrucción, quintil de riqueza (clasificado en cinco niveles de riqueza), área de residencia (clasificada como urbano y rural), dominio geográfico (clasificado como Lima Metropolitana, resto de la Costa, Sierra y Selva), cobertura de salud (clasificada como sin cobertura y con cobertura), consumo de alcohol (sí/no), hábito de fumar (sí/no) y presencia de discapacidad (sí/no). Se realizaron análisis de frecuencias absolutas y relativas, diferencias de proporciones y un análisis multivariado mediante modelos lineales generalizados. Resultados: La prevalencia del trastorno depresivo fue del 13,18 % y de la discapacidad, 7,86 %. Los adultos mayores de sexo masculino tuvieron menos probabilidades de padecer trastorno depresivo (RPa = 0,602; IC 95 %: 0,513-0,706) que las mujeres, así como los integrantes del grupo etario de mayores de 85 años presentaron mayor riesgo que los de 60 a 74 (RPa = 1,664; IC 95 %: 1,304-2,124). Además, el no padecer de alguna discapacidad se comportó como un factor preventivo (RPa = 0,542; IC 95 %: 0,440-0,668), mientras que un mayor grado de instrucción y quintil de riqueza, desde el quintil "medio", indicaron también ser factores de protección al tomarse como referencia las categorías "sin educación" y "los más pobres", respectivamente (p < 0,005). Conclusiones: El pertenecer al grupo de mayores de 85 años, del sexo femenino, de bajos quintiles de riqueza, padecer de alguna discapacidad y tener un menor grado de instrucción constituyen factores de riesgo para el trastorno depresivo en adultos mayores peruanos.

Objective: To determine the prevalence and factors associated with depressive disorder among Peruvian older adults over 60 years of age. Materials and methods: An observational, analytical and cross-sectional study was conducted based on a secondary analysis of the 2019 Encuesta Demográfica y de Salud Familiar (ENDES National Demographic and Family Health Survey), administered at national level by Instituto Nacional de Estadística e Informática del Perú (INEI National Institute of Statistics and Informatics of Peru). The sample consisted of 4,174 older adults. The main variable was suffering from a depressive disorder (depressed/not depressed) and the independent variables were age, sex, educational level, wealth quintile (classified into five levels of wealth), area of residence (classified as urban/rural), geographic domain (classified as Lima Metropolitan Area, the rest of the coast, the highlands and the jungle), health coverage (classified as insured/uninsured), alcohol consumption (yes/no), smoking (yes/no) and presence of a disability (yes/no). Analyses of absolute and relative frequencies, differences in proportions and a multivariate analysis using generalized linear models (GLM) were performed. Results: The prevalence of depressive disorder and disability accounted for 13.18 % and 7.86 %, respectively. Older males were less likely to suffer from a depressive disorder (PRa = 0.602; 95 % CI: 0.513-0.706) than females, and the group over 85 years of age showed a higher risk than those from 60 to 74 years (PRa = 1.664; 95 % CI: 1.304-2.124). Besides, not presenting a disability behaved as a preventive factor (PRa = 0.542; 95 % CI: 0.440-0.668), while a higher educational level and wealth quintile, starting from the "Middle" quintile, were protective factors when taking the categories "No education" and "The poorest" as reference, respectively (p < 0.005). Conclusions: Belonging to the group over 85 years of age, being a female, being in lower wealth quintiles, suffering from a disability and having a lower educational level were risk factors for depressive disorder among Peruvians older adults.

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Three new styrylquinoline-chalcone hybrids have been synthesized using a three-step pathway starting with Friedländer cyclocondensation between (2-aminophenyl)chalcones and acetone to give 2-methyl-4-styrylquinolines, followed by selective oxidation to the 2-formyl analogues, and finally Claisen-Schmidt condensation between the formyl intermediates and 1-acetylnaphthalene. All intermediates and the final products have been fully characterized by IR and 1H/13C NMR spectroscopy, and by high-resolution mass spectrometry, and the three products have been characterized by single-crystal X-ray diffraction. The molecular conformations of (E)-3-{4-[(E)-2-phenylethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H21NO, (IVa), and (E)-3-{4-[(E)-2-(4-fluorophenyl)ethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H20FNO, (IVb), are very similar. In each compound, the molecules are linked into a three-dimensional array by hydrogen bonds, of the C-H...O and C-H...N types in (IVa), and of the C-H...O and C-H...π types in (IVb), and by two independent π-π stacking interactions. By contrast, the conformation of the chalcone unit in (E)-3-{4-[(E)-2-(2-chlorophenyl)ethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H20ClNO, (IVc), differs from those in (IVa) and (IVb). There are only weak hydrogen bonds in the structure of (IVc), but a single rather weak π-π stacking interaction links the molecules into chains. Comparisons are made with some related structures.

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Three new 2-methyl-4-styrylquinoline derivatives have been synthesized in high yields using Friedländer reactions between chalcones [1-(2-aminophenyl)-3-arylprop-2-en-1-ones] and acetone, and characterized using IR, 1H and 13C NMR spectroscopy, and mass spectrometry, and by crystal structure analysis. In (E)-4-(4-fluorostyryl)-2-methylquinoline, C18H14FN, (I), the molecules are joined into cyclic centrosymmetric dimers by C-H...N hydrogen bonds and these dimers are linked into sheets by π-π stacking interactions. The molecules of (E)-2-methyl-4-[4-(trifluoromethyl)styryl]quinoline, C19H14F3N, (II), are linked into cyclic centrosymmetric dimers by C-H...π hydrogen bonds and these dimers are linked into chains by a single π-π stacking interaction. There are no significant hydrogen bonds in the structure of (E)-4-(2,6-dichlorostyryl)-2-methylquinoline, C18H13Cl2N, (III), but molecules related by translation along [010] form stacks with an intermolecular spacing of only 3.8628 (2) Å. Comparisons are made with the structures of some related compounds.

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Background: Commensal microflora such as Escherichia coli and Enterococcus spp. are representative indicators of antimicrobial resistance (AMR) as they are part of the normal intestinal microflora and can acquire and disseminate AMR to pathogenic or zoonotic bacteria like Salmonella spp. Objective: To investigate the state of AMR among E. coli and Salmonella spp., potential pathogens in humans, isolated from cecal contents of pigs submitted to a veterinary diagnostic laboratory in Colombia from 2016 to 2019. Methods: Susceptibility testing was conducted using the Kirby-Bauer disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines for antimicrobial zone diameter breakpoints. An E. coli strain (ATCC 25922) was used as the quality control organism. Isolates showing resistance to three or more antimicrobial classes were classified as multidrug-resistant (MDR) as defined by a joint group of the European Centre for Disease prevention and Control and the Center for Disease Control and Prevention of the USA. Results: A total of 112 E. coli and 192 Salmonella spp. colonies were isolated from 557 samples received between 2016 and 2019. In order of decreasing frequency, E. coli was resistant to tetracycline (100%), sulfamethoxazol-trimethoprim (97.5%), amoxicillin (86.4%), enrofloxacin (82.6%), tylosin (82.1%), doxycycline (59%), neomycin (50%), ciprofloxacin (45.5%), ceftiofur (35%), gentamicin (30%), tilmicosin (29%), and fosfomycin (12.5%). When compared with E. coli, Salmonella spp. was generally resistant to the same agents with slightly less resistance (between 10-30%) to eight of the antimicrobials tested. Salmonella spp. showed <20% resistance to three antimicrobials, as follows: neomycin (17%), gentamicin (16%), and fosfomycin (14%). Multi-resistance occurred in 68.7% (77/112) of E. coli and 70.3% (135/192) of Salmonella spp. isolates. Resistance of Salmonella spp. was alarming to all the critically important antimicrobials tested: fluoroquinolones (enrofloxacin, ciprofloxacin), ceftiofur (third- generation cephalosporin), and macrolides (tylosin). Conclusions: According to our results, there is a high level of multi- drug resistance (MDR) in E. coli and Salmonella spp. It is necessary to implement a nationwide antimicrobial resistance monitoring program in Colombia, together with proper antimicrobial prescribing guidelines for pigs. The indiscriminate use of antimicrobial growth promoters by the swine industry is generating widespread bacterial resistance and should be discontinued.

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Antecedentes: Flora comensal como espécies de Escherichia coli e Enterococcus são tipicamente escolhidas como indicadores representativos de la resistência antimicrobiana (AMR), pois fazem parte da flora intestinal normal e podem adquirir e disseminar AMR a bactérias patogênicas ou zoonóticas como Salmonella spp. Objetivo: Investigar o estado da AMR entre E. coli e Salmonella spp. isolados do conteúdo cecal de porcos colombianos submetidos ao Laboratório de Diagnóstico Veterinário de 2016 a 2019, ambos sendo patógenos potenciais em humanos. Métodos: O teste de suscetibilidade foi conduzido usando o método de difusão em disco Kirby-Bauer de acordo com as diretrizes do Instituto de Padrões Clínicos e Laboratoriais para pontos de quebra de diâmetro da zona antimicrobiana. A cepa de E. coli (ATCC 25922) foi usada como organismo de controle de qualidade. Os isolados que apresentam resistência a três ou mais classes de antimicrobianos foram classificados como multirresistentes (MDR), conforme definido por um grupo conjunto do Centro Europeu para Prevenção e Controle de Doenças e Centro para Controle e Prevenção de Doenças dos EUA. Resultados: Um total de 112 E. coli e 192 Salmonella spp. foram isolados de 557 amostras submetidas entre 2016 e 2019. Em ordem decrescente de frequência, a resistência a E. coli foi: tetraciclina (100%), sulfametoxazol-trimetoprim (97,5%), amoxicilina (86,4%), enrofloxacina (82,6%), tilosina (82,1%), doxiciclina (59%), neomicina (50%), ciprofloxacina (45,5%), ceftiofur (35%), gentamicina (30%), tilmicosina (29%) e fosfomicina (12,5%). Quando comparada com E. coli, Salmonella spp. foi geralmente resistente aos mesmos agentes com resistência ligeiramente menor (entre 10-30%) a oito dos antimicrobianos. Apenas três antimicrobianos apresentaram resistência a Salmonella spp. abaixo de 20% da seguinte forma: neomicina (17%), gentamicina (16%) e fosfomicina (14%). Multi-resistência ocorreu em 68,7% (77/112) de E. coli e 70,3% (135/192) de Salmonella spp. isolados. Resistência de Salmonella spp. foi alarmante para todos os antimicrobianos criticamente importantes testados: fluoroquinolonas (enrofloxacina, ciprofloxacina), ceftiofur (cefalosporina de terceira geração) e macrolídeos (tilosina). Conclusões: Esses resultados indicam um alto nível de resistência a múltiplos medicamentos (MDR) e que um Programa Nacional de Monitoramento da Resistência Antimicrobiana é necessário para a Colômbia, juntamente com a implementação de diretrizes de prescrição de antimicrobianos para suínos. O uso indiscriminado de antimicrobianos para promoção de crescimento na indústria suína está claramente promovendo resistência generalizada e deve ser interrompido.

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Despite intensive research during the last few decades, understanding of ecological and physiological factors related to haemosporidian infections in birds is still fragmentary. Since more model organisms are needed in order to understand these infections in the wild, we analysed avian haemosporidian infections in the rufous-collared sparrow (Zonotrichia capensis, Emberizidae) in a dry forest of the Ecuadorian Andes. Parasite diversity was screened using molecular and morphological approaches. By molecular diagnosis, we identified three linages that were phylogenetically placed in the context of molecular haemosporidian diversity and associated with a morphospecies. By microscopy, we identified five described morphospecies and one additional undescribed morphospecies. We found that avian haemosporidian prevalence on the study site was 76.3%. Additionally, we used a series of generalized linear models to explore the potential relationship of parasite prevalence and parasitaemia with a set of variables related to physiological and environmental conditions. Although our results revealed associations of haemosporidian infections with precipitation, age and sampling site, the models only explained a small fraction of the variation.

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RESUMEN Antecedentes: El trastorno conversivo es un reto para los clínicos por los vacíos conceptuales en lo que respecta a la patogenia y cómo confluyen otras entidades psiquiátricas y la falta de aproximaciones a las vivencias tanto de pacientes como de familiares con la enfermedad. Objetivo: Describir los modelos explicativos (ME) que utilizan los cuidadores de niños y adolescentes con trastorno conversivo que consultan al Hospital Pediátrico de La Misericordia. Métodos: Se realizó un estudio cualitativo con una muestra por conveniencia de 10 casos atendidos entre mayo de 2014 y abril de 2015. La herramienta usada fue una entrevista en profundidad con padres y/o cuidadores. Resultados: Los cuidadores tienen diversas creencias en torno al origen de los síntomas, y consideran principalmente enfermedad, factores mágicos místicos y factores psicosociales. Se explican los síntomas en cada caso de varias maneras, y no se encontró una relación directa entre estas creencias, el patrón de síntomas y los comportamientos de búsqueda de ayuda. La presentación sintomática es polimorfa y genera interferencia principalmente en la actividad escolar de los pacientes. La atención médica se percibe como pertinente y la atención psiquiátrica, como insuficiente. Entre los itinerarios terapéuticos, se describen consultas con diversos agentes, además de la atención médica, incluidas medicinas alternativas y enfoques mágico-religiosos. Conclusiones: Los ME en trastorno conversivo son variados, pero incluyen con frecuencia elementos mágico-religiosos y factores psicosociales. Las creencias subyacentes no se relacionan directamente con la búsqueda de ayuda u otras variables.

ABSTRACT Background: Conversion disorder is a challenge for clinicians due to the conceptual gaps as regards its pathogenesis, the way in which it converges with other psychiatric disorders, and the lack of approaches to the experiences of both patients and family members with the disease. Objective: To describe Explanatory Models (EM) offered to caregivers of paediatric patients with conversion disorder who attended the Hospital de la Misericordia. Methods: A qualitative study was conducted with a convenience sample of 10 patients who attended the Hospital de La Misericordia, ¿Bogotá? between May 2014 and April 2015. The tool used was an in-depth interview applied to parents and/or caregivers. Results: Caregivers have different beliefs about the origin of the symptoms, especially considering sickness, magical-mystical factors, and psychosocial factors. The symptoms are explained in each case in various ways and there is no direct relationship between these beliefs, the pattern of symptoms, and help-seeking behaviours. Symptomatic presentation is polymorphous and mainly interferes in the patient's school activities. The medical care is perceived as relevant, and psychiatric care as insufficient. Among the therapeutic routes, consultations with various agents are described, including medical care, alternative medicine, and magical-religious approaches. Conclusions: EMs in conversion disorder are varied, but often include magical-religious elements and psychosocial factors. The underlying beliefs are not directly related to help-seeking behaviours or other variables.

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Vector ecology is a key factor in understanding the transmission of disease agents, with each species having an optimal range of environmental requirements. Scarce data, however, are available for how interactions of local and broad-scale climate phenomena, such as seasonality and the El Niño Southern Oscillation (ENSO), affect simuliids. We, therefore, conducted an exploratory study to examine distribution patterns of species of Simuliidae along an elevational gradient of the Otún River in the Colombian Andes, encompassing four ecoregions. Larval and pupal simuliids were sampled at 52 sites ranging from 1800 to 4750 m above sea level in dry and wet seasons and during the La Niña phase (2011-2012) and the El Niño phase (2015-2016) of the ENSO; physicochemical measurements were taken during the El Niño phase. Twenty-seven species in two genera (Gigantodax and Simulium) were collected. Species richness and occurrence in each ecoregion were influenced by elevation, seasonality, and primarily the warm El Niño and cool La Niña phases of the ENSO. The degree of change differed among ecoregions and was related to physicochemical factors, mainly with stream discharge. Some putative simuliid vectors of Leucocytozoon, such as G. misitu and S. muiscorum, markedly changed in distribution and occurrence, potentially influencing parasite transmission.

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The great diversity of birds and ecosystems in the Andean mountains has been understudied in terms of their parasite species. We describe a new Haemoproteus parasite, H. (Parahaemoproteus) erythrogravidus infecting Zonotrichia capensis (Rufous-Collared Sparrow) in South America. The description of this blood parasite species is supported by morphological and molecular data based on a fragment of cytochrome b gene (cyt b) and complete mitochondrial genome sequences. The new species is closely related to H. (Parahaemoproteus) coatneyi, and it can be readily distinguished from the latter parasite due to morphology of its blood stages, particularly 1) the formation of a marked protrusion on envelope of infected erythrocytes by the majority of developing gametocytes, a feature which is unique for this Haemoproteus species and 2) the extremely attenuated width of the growing dumbbell-shaped macro- and microgametocytes. Additionally, Haemoproteus erythrogravidus is shown to be a monophyletic taxon that diverges from Haemoproteus coatneyi at the molecular level. We provide the complete mitochondrial DNA genome for both H. coatneyi and H. erythrogravidus. Molecular and morphological evidences indicate that H. erythrogravidus is present in Ecuador and Colombia, and genetic lineages with 100% of identity for the cyt b gene were reported in Chile, Perú, and Venezuela. Our study also indicates that H. erythrogravidus and H. coatneyi are sympatric sister taxa sharing Z. capensis as a host species across its distribution, which could be the result of sympatric speciation or complex biogeographic processes. Further studies on the distribution and evolutionary history of Z. capensis and its parasites H. erythrogravidus and H. coatneyi insight for our better understanding of the factors and dynamics driving parasite speciation.

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Studies of the lowland avifauna in the Neotropical Region have shown a paucity of Leucocytozoon species. However, surveys conducted in the Colombian highlands revealed a great diversity of these parasites infecting resident birds. To further investigate the relationship between Leucocytozoon diversity, the potential vectors, and altitudinal distribution, birds from 41 families were sampled at low and high elevations in Colombia. Blood samples were screened by microscopy, and a fragment of cytochrome b was amplified from Leucocytozoon-positive samples. The complete mitochondrial genome was also obtained for each morphospecies of Leucocytozoon. Leucocytozoon species were detected in resident birds, with various degrees of host specificity, at elevations from 2,400 to 3,950 meters above sea level, where five new host-parasite associations were discovered. Phylogenetic analysis based on the cytochrome b fragment suggested that two nominal taxa, L. fringillinarum and L. majoris, are species complexes. Blood sources of Simuliidae revealed generalist-feeding habits that included avian and mammalian hosts. Molecular analysis of parasites in black flies indicated a close relationship with the parasites found in birds. Our investigation provides further evidence that the distribution and transmission of Leucocytozoon species in the Neotropics are influenced by elevation, with the highest prevalence between 2,400 and 3,200 m asl.

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Little is known about the oviposition habits and egg structure of Neotropical members of the Simuliidae family. The oviposition behavior of Simulium dinellii (Joan) was observed near at Otún Quimbaya, Colombia. Small groups of females hovered about 2 cm above the water surface to oviposit. Some of these females had been capture and the eggs were obtained. These eggs were counted, measured and processed by scanning electron microscopy. Subtriangular eggs had a latticework of polygons on the endochorionic surface. Chorionic differences between the eggs of S. dinellii and the few previously studied species suggest potential taxonomic value of egg microstructure.

El conocimiento sobre los hábitos de oviposición y estructura de los huevos de la familia Simuliidae es muy escaso. En este estudio se observó el comportamiento de oviposición de Simulium dinellii (Joan) en quebradas cercanas al Santuario de fauna y flora Otún Quimbaya, Colombia. El cual consistió en la formación de pequeños grupos de hembras que sobrevolaban a 2 cm de la superficie del agua para ovipositar, algunas de estas hembras fueron colectadas, obteniendo así los huevos, los cuales fueron contados, medidos y procesados por Microscopia Electrónica de Barrido con el fin de caracterizar la estructura endocoriónica. Los huevos presentaron una forma subtriangular, con una entramado poligonal sobre la superficie. Las características morfológicas observadas en los huevos de S. dinellii fueron diferentes a las previamente reportadas en otras especies de la familia Simuliidae, sugiriendo un posible valor taxonómico de la microestructura del huevo.

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Plasmodium (Novyella) unalis sp. nov. was found in the Great Thrush, Turdus fuscater (Passeriformes, Turdidae) in Bogotá, Colombia, at 2,560 m above sea level where the active transmission occurs. This parasite is described based on the morphology of its blood stages and a fragment of the mitochondrial cytochrome b gene (lineage UN227). Illustrations of blood stages of new species are given, and the phylogenetic analysis identifies closely related species and lineages of avian malaria parasites. The new species is most similar to Plasmodium (Novyella) vaughani (lineage SYAT05), a cosmopolitan avian malaria parasite; these parasites are also closely related genetically, with a genetic difference of 3.2% between them. P. unalis can be readily distinguished from the latter species morphologically, primarily due to the (1) presence of a single large, circular shaped pigment granule in the erythrocytic trophozoites and meronts; (2) presence of prominent vacuoles in trophozoites and growing meronts; and (3) presence of predominantly fan-like shaped erythrocytic meronts. Cytochrome b lineages with high similarity to the new species have been reported in Costa Rica, Brazil, Chile, and USA. It is probable that the new species of malaria parasite is widely distributed in the New World. This parasite has been reported only in the Great Thrush at the study site and might have a narrow range of avian hosts. Records of P. unalis are of particular theoretical interest due to its active transmission at highlands in Andes. Possible influence of urbanization on transmission of this malaria parasite in Bogotá is discussed.

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This study reports a broadening of the altitudinal range and a new host for Plasmodium (Haemamoeba) lutzi in Colombia. The study was conducted in the city of Bogotá, located in the Eastern Cordillera of Colombia at 2,560 m asl (meters above sea level) with an average annual temperature of 15 C. In total, 156 specimens of birds belonging to 25 species and 14 families were captured using mist nets. The blood samples were collected through venipuncture and analyzed by light microscopy. Plasmodium (H.) lutzi was only found in 2 individuals of Turdus fuscater (Great Thrush). This parasite has previously been reported in Aramides cajaneus (before: Aramides cajanea) (Grey-Necked Wood Rail), a bird found in the lowlands of Brazil, Venezuela, and Colombia. This finding provides evidence for a broad host range for P. lutzi that include 2 different orders, Gruiformes and Passeriformes, and also altitudinal expansion of its distribution. The blood stages were compared with the parasite's original descriptions, and the sequence of the parasite's mitochondrial genome (mtDNA) confirms that P. lutzi is a sister taxa of Plasmodium relictum, as previously proposed.

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The females, males, pupae, and larvae of two new species of Simulium are described and illustrated from a small stream 3950 m above sea level in the Lake Otún area of the Colombian Andes Mountains. Simulium (Pternaspatha) quimbayium n. sp. represents a 630-km northeastern extension of the distributional range of previously known members of the subgenus Pternaspatha, and Simulium (Psilopelmia) machetorum n. sp. represents the highest altitude recorded for a species of the subgenus Psilopelmia. These species illustrate the unique simuliid biodiversity in the páramo ecosystem of the high northern Andes.

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Se describe la interrelación entre el sistema nervioso y la etiopatogenia y fisiopatología del prurito, lo que se denomina la neurobiología cutánea. Se describe los últimos estudios sobre los diferentes mecanismos patogénicos de la producción del prurito entre los cuales se describe una serie de vías, receptores, neurotransmisores y además se discute el papel de los aspectos psicológicos en el prurito especialmente el relacionado con los diversos tipos de eccema.

Interrelation between nervous system and etiopathogeny and pathophysiologyis described, this is known as cutaneous neurobiology. The last studies about the pathogenic mechanisms of production of pruritus like receptors, neurtransmisors and psicological aspects are described, specially pruritus associated to diverse kinds of eczema.

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