RESUMEN
Giardia duodenalis genotypes A and B have been reported in Colombia. The population consisted of 235 schoolchildren whose ages ranged from 2 to 10 yr of age from the municipalities of Soledad and Galapa in the department of Atlántico, Colombia. Fecal samples were obtained and then analyzed in triplicate using the sedimentation in formalin-ether (Ritchie's method) and direct examination techniques. Of the 235 fecal samples, 35 samples were positive for G. duodenalis; positive samples were concentrated in a sucrose gradient and sonicated for 3 cycles of 20 sec. DNA extraction was performed, and the parasites were genotyped by conventional PCR amplifying a region of the ß-giardin gene. A general prevalence of G. duodenalis of 13.2% was found, and of these genotyped samples, 13 (56.7%) and 7 (20%) corresponded to genotype A, 1 (4.3%), and 3 (25%) corresponded to genotype B, and 9 (39.1%) and 2 (16.7%) were not defined, in the municipalities Soledad and Galapa, respectively. Additionally, 23 children were diagnosed with symptomatologic giardiasis, and 12 were asymptomatic; the most relevant symptoms were abdominal pain (7, 20%) and diarrhea (13, 56.7%). The nutritional status of children with Giardia genotypes A and B were as follows: 3 in a state of malnutrition (10%), 10 normal (33.3%), and 6 overweight and obese (20%) with genotype A, and 1 in a state of malnutrition (3.3%) and 3 normal (10%) with genotype B. The genotypes found in G. duodenalis did not show an association with nutritional status or with the clinical manifestations evaluated in schoolchildren.
Asunto(s)
Giardia lamblia/clasificación , Giardiasis/parasitología , Desnutrición/complicaciones , Estado Nutricional/fisiología , Niño , Preescolar , Colombia , Genotipo , Técnicas de Genotipaje , Giardia lamblia/genética , Giardiasis/complicaciones , Giardiasis/fisiopatología , Humanos , Desnutrición/parasitologíaRESUMEN
BACKGROUND: Blastocystis spp. (Blastocystis) is a widely distributed gastrointestinal protist frequently reported in countries with tropical and sub-tropical climate. We sought to determine the factors associated with Blastocystis infection and investigate its role on biomarkers of intestinal health among slum-dwelling malnourished adults in Bangladesh. METHODOLOGY: Total 524 malnourished adults with a body mass index ≤18.5 kg/m2 were included in this analysis. Presence of Blastocystis in feces was evaluated by TaqMan Array Card assays. PRINCIPAL FINDINGS: Blastocystis was tested positive in 78.6% of the participants. Prevalence of infection with atypical strains of enteropathogenic Escherichia coli (aEPEC) (56% vs. 38%, p<0.001), and Trichuris trichiura (28% vs. 15%, p-value = 0.02) was significantly greater in adults with Blastocystis, while Giardia intestinalis was significantly lower (8% vs. 14%, p-value = 0.04) in Blastocystis positive adults. Malnourished adults who were living in households with high crowding index (aOR = 2.18; 95% CI = 1.11, 4.65; p-value = 0.03), and infected with aEPEC (aOR = 2.14; 95% CI = 1.35, 3.44; p-value = 0.001) and Trichuris trichiura (aOR = 1.97; 95% CI = 1.08, 3.77; p = 0.03) were more likely to be infected with Blastocystis. A significant negative relationship was observed between Blastocystis and fecal concentrations of alpha-1 antitrypsin (ß = -0.1; 95% CI = -1.7, -0.1; p-value<0.001) and Reg1B (ß = -3.6; 95% CI = -6.9, -3.0; p-value = 0.03). CONCLUSIONS: The study findings suggest that the presence of Blastocystis in human intestine influences gut health and may have potential pathogenic role in presence of other pathogens.
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Infecciones por Blastocystis/economía , Blastocystis/fisiología , Enfermedades Intestinales/parasitología , Desnutrición/epidemiología , Adolescente , Adulto , Bangladesh/epidemiología , Infecciones por Blastocystis/epidemiología , Infecciones por Blastocystis/parasitología , Heces/parasitología , Femenino , Humanos , Enfermedades Intestinales/economía , Enfermedades Intestinales/epidemiología , Masculino , Desnutrición/economía , Desnutrición/parasitología , Áreas de Pobreza , Población Rural/estadística & datos numéricos , Adulto JovenAsunto(s)
Diarrea/parasitología , Heterophyidae/aislamiento & purificación , Desnutrición/parasitología , Infecciones por Trematodos/diagnóstico , Animales , Biopsia , Niño , Enfermedad Crónica , Diarrea/diagnóstico , Duodenoscopía , Duodeno/diagnóstico por imagen , Duodeno/parasitología , Duodeno/patología , Humanos , Mucosa Intestinal/diagnóstico por imagen , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Masculino , Desnutrición/diagnóstico , Imagen de Banda Estrecha , Infecciones por Trematodos/complicaciones , Infecciones por Trematodos/parasitologíaRESUMEN
Cryptosporidium, as a small protozoan parasite, is a leading cause of persistent diarrhea in children in developing countries and has both a short and long-term impact on the growth of children. In the present study, Cryptosporidium infection was compared in malnourished and well-nourished children by modified acid-fast staining, nested-polymerase chain reaction (nested-PCR) and loop-mediated isothermal amplification (LAMP) methods. As a case-control study, Cryptosporidium infection in 94 malnourished children was evaluated and compared with those of 188 age and gender-matched well-nourished children. Oocysts of Cryptosporidium were detected by modified acid-fast staining method. The extracted DNA was amplified by nested-PCR and LAMP techniques. In addition, positive amplicons were directly sequenced for phylogenetic analysis. Cryptosporidium oocysts were found in the stools of two (2.12 %) children who were hospitalized and had diarrhea by nested-PCR while three isolates (3.2 %) were found by LAMP. Cryptosporidium-positive children were more malnourished compared to those who were negative for Cryptosporidium infection but this important finding was not statistically significant. C. parvum was the main species of Cryptosporidium detected in malnourished children in northwest Iran. LAMP can be considered as a sensitive field monitoring assay in patients with low parasite burden. Nutritional status and socio-demographic factors may have interactive effects on the incidence and severity of parasitic diseases.
Asunto(s)
Criptosporidiosis/complicaciones , Criptosporidiosis/fisiopatología , Desnutrición/parasitología , Estado Nutricional , Factores Socioeconómicos , Estudios de Casos y Controles , Niño , Preescolar , Cryptosporidium/aislamiento & purificación , ADN Protozoario/genética , Diarrea/parasitología , Heces/parasitología , Femenino , Humanos , Lactante , Recién Nacido , Irán , Masculino , Oocistos/aislamiento & purificación , Carga de ParásitosRESUMEN
Protein malnutrition is a risk factor for developing visceral leishmaniasis. Because we previously demonstrated that protein malnutrition and infection with Leishmania infantum disrupts the splenic microarchitecture in BALB/c mice, alters T cell-subsets and increases splenic parasite load, we hypothesize that splenic microenvironment is precociously compromised in infected animals that suffered a preceding malnutrition. To evaluate this, we characterized the abundance of proteins secreted in the splenic interstitial fluid (IF) using an iTRAQ-based quantitative proteomics approach. In addition, local levels of pro-inflammatory and proliferation molecules were analyzed. Whereas well-nourished infected animals showed increased IL-1ß and IL-2 levels, malnourished-infected mice displayed significant reduction of these cytokines. Remarkably, a two-weeks infection with L. infantum already modified protein abundance in the splenic IF of well-nourished mice, but malnourished animals failed to respond to infection in the same fashion. Malnutrition induced significant reduction of chemotactic and pro-inflammatory molecules as well as of proteins involved in nucleic acid and amino acid metabolism, indicating an impaired proliferative microenvironment. Accordingly, a significant decrease in Ki67 expression was observed, suggesting that splenocyte proliferation is compromised in malnourished animals. Together, our results show that malnutrition compromises the splenic microenvironment and alters the immune response to the parasite in malnourished individuals. SIGNIFICANCE: Protein malnutrition is recognized as an important epidemiological risk factor for developing visceral leishmaniasis (VL). Locally secreted factors present in the interstitial fluid have important roles in initiating immune responses and in regulating fluid volume during inflammation. However, the regulation of secreted factors under pathological conditions such as malnutrition and infection are widely unknown. To analyze how protein malnutrition alters secreted proteins involved in the immune response to L. infantum infection we evaluated the proteomic profile of the interstitial fluid of the spleen in malnourished BALB/c mice infected with L. infantum. Our work revealed new elements that contribute to the understanding of the immunopathological events in the spleen of malnourished animals infected with L. infantum and opens new pathways for consideration of other aspects that could improve VL treatment in malnourished individuals.
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Proliferación Celular , Líquido Extracelular/metabolismo , Perfilación de la Expresión Génica , Leishmania infantum/metabolismo , Leishmaniasis Visceral/metabolismo , Desnutrición/metabolismo , Proteómica , Bazo/metabolismo , Animales , Líquido Extracelular/parasitología , Inflamación/metabolismo , Inflamación/parasitología , Inflamación/patología , Leishmaniasis Visceral/patología , Masculino , Desnutrición/parasitología , Desnutrición/patología , Ratones , Ratones Endogámicos BALB C , Bazo/parasitología , Bazo/patologíaRESUMEN
Detrimental effects of malnutrition on immune responses to pathogens have long been recognized and it is considered a main risk factor for various infectious diseases, including visceral leishmaniasis (VL). Thymus is a target of both malnutrition and infection, but its role in the immune response to Leishmania infantum in malnourished individuals is barely studied. Because we previously observed thymic atrophy and significant reduction in cellularity and chemokine levels in malnourished mice infected with L. infantum, we postulated that the thymic microenvironment is severely compromised in those animals. To test this, we analyzed the microarchitecture of the organ and measured the protein abundance in its interstitial space in malnourished BALB/c mice infected or not with L. infantum. Malnourished-infected animals exhibited a significant reduction of the thymic cortex:medulla ratio and altered abundance of proteins secreted in the thymic interstitial fluid. Eighty-one percent of identified proteins are secreted by exosomes and malnourished-infected mice showed significant decrease in exosomal proteins, suggesting that exosomal carrier system, and therefore intrathymic communication, is dysregulated in those animals. Malnourished-infected mice also exhibited a significant increase in the abundance of proteins involved in lipid metabolism and tricarboxylic acid cycle, suggestive of a non-proliferative microenvironment. Accordingly, flow cytometry analysis revealed decreased proliferation of single positive and double positive T cells in those animals. Together, the reduced cortical area, decreased proliferation, and altered protein abundance suggest a dysfunctional thymic microenvironment where T cell migration, proliferation, and maturation are compromised, contributing for the thymic atrophy observed in malnourished animals. All these alterations could affect the control of the local and systemic infection, resulting in an impaired response to L. infantum infection.
Asunto(s)
Interacciones Huésped-Patógeno/inmunología , Leishmania infantum/inmunología , Leishmaniasis Visceral/inmunología , Desnutrición/inmunología , Linfocitos T/inmunología , Timo/inmunología , Animales , Transporte Biológico , Movimiento Celular , Proliferación Celular , Ciclo del Ácido Cítrico/genética , Ciclo del Ácido Cítrico/inmunología , Exosomas/inmunología , Exosomas/metabolismo , Exosomas/parasitología , Líquido Extracelular/inmunología , Líquido Extracelular/metabolismo , Líquido Extracelular/parasitología , Galectina 1/genética , Galectina 1/inmunología , Regulación de la Expresión Génica , Interacciones Huésped-Patógeno/genética , Inmunidad Innata , Leishmania infantum/crecimiento & desarrollo , Leishmaniasis Visceral/genética , Leishmaniasis Visceral/metabolismo , Leishmaniasis Visceral/parasitología , Metabolismo de los Lípidos , Masculino , Desnutrición/genética , Desnutrición/metabolismo , Desnutrición/parasitología , Ratones , Ratones Endogámicos BALB C , Plasminógeno/genética , Plasminógeno/inmunología , Proteoma/genética , Proteoma/inmunología , Linfocitos T/parasitología , Timo/metabolismo , Timo/parasitologíaRESUMEN
INTRODUCTION: it has previously been shown that parasitic infections (PI) have deleterious effects on the nutritional status of the host, particularly among young children. OBJECTIVE: the objective of this study was to estimate the severity of the problem of malnutrition and anemia in association with PI in preschool children and to identify the possible risk factors that contribute to these health problems. METHODS: four hundred and thirty-seven mother-child pairs were randomly selected from rural areas of Peshawar, Pakistan. Children with visible and invisible worms were identified. The nutritional status of the respondents was evaluated. Structured questionnaires were used to collect data on relevant parameters. Appropriate statistical tests were used to analyze the data. RESULTS: the average age of the children was 24 ± 10 months. A total of 120 (27.5%) fecal samples of children tested positive for several parasites. Of the total, 267 (61%), 205 (47%), 109 (25%) and 140 (32%) children were anemic, stunted, wasted and underweight, respectively. The majority of wasted children (59% wasted versus 41% normal) and anemic (66% anemic versus 34% non-anemic) were infected with parasites (p < 0.05). Independent factors related to child anemia included child age, family size, mothers' awareness of overall child healthcare, and PIs. PIs were independent risk factors for malnutrition and general child wasting. Sociodemographic, parental and child-related risk factors for PIs included mothers' poor nutritional status and awareness level regarding overall child healthcare, fathers' formal education, child's pica habit, child's age, open sewage system in the houses and family size. CONCLUSION: in general, malnutrition and anemia were highly prevalent in children in association with PI.
Asunto(s)
Anemia/epidemiología , Desnutrición/epidemiología , Enfermedades Parasitarias/epidemiología , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Desnutrición/parasitología , Estado Nutricional , Pakistán/epidemiología , Enfermedades Parasitarias/parasitología , Prevalencia , Factores de Riesgo , Población RuralRESUMEN
BACKGROUND: Malaria, anaemia and malnutrition are frequently co-existing diseases that cause significant morbidity and mortality particularly among children. This study measured the prevalence, intensity and evaluated risk factors for malaria parasitaemia, anaemia and malnutrition among children living at low versus high altitude settings in the Mount Cameroon area. METHODS: A cross-sectional community based survey involving 828 children aged 6 months to 14 years was conducted between July and November 2017. Malaria parasitaemia was confirmed by light microscopy, haemoglobin concentration was measured using an auto haematology analyser, nutritional status was determined from the anthropometric measurements collected, and socioeconomic status related variables by the use of questionnaire. Anaemia and malnutrition were defined according to World Health Organization standards. Associations between predictor variables and primary outcomes were assessed using logistic regression analysis. RESULTS: Malaria parasite and anaemia were prevalent in 41.7% and 56.2% of the children, respectively while, malnutrition prevalence was 34.8% with wasting, underweight and stunting occurring in 25.7%, 19.9% and 23.7% of them respectively. Overall malaria parasite geometric mean density was 413/µL of blood (range 100-27,060). The odds of having malaria parasitaemia was highest in children 5-9 years of age [odd ratio (OR) = 1.69, P = 0.006], living in lowland (OR = 1.48, P = 0.008) as well as those whose domestic water was collected from an open source (streams/springs) (OR = 1.81, P = 0.005) than their counterparts. Being < 5 years (OR = 3.15, P = < 0.001) or 5-9 years (OR = 2.20, P < 0.001) of age, having malaria parasite (OR = 2.07, P = < 0.001) and fever in the past 2 days (OR = 1.52, P < 0.04) were identified as significant risk factors of anaemia while the age group < 5 years was the only significant risk (OR = 3.09, P = < 0.001) associated with malnutrition. CONCLUSION: While age specific attention should be given in the control of malaria (5-9 years), anaemia (< 10 years) and malnutrition (< 5 years), the existing malaria control programmes should be revised to integrate anaemia and malnutrition control strategies so as to improve upon the health of the children.
Asunto(s)
Altitud , Anemia/epidemiología , Malaria/epidemiología , Desnutrición/epidemiología , Parasitemia/epidemiología , Adolescente , Anemia/parasitología , Camerún/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Malaria/parasitología , Masculino , Desnutrición/parasitología , Parasitemia/parasitología , Prevalencia , Salud Pública , Factores de RiesgoRESUMEN
Background: Cryptosporidium species are enteric protozoa that cause significant morbidity and mortality in children worldwide. We characterized the epidemiology of Cryptosporidium in children from 8 resource-limited sites in Africa, Asia, and South America. Methods: Children were enrolled within 17 days of birth and followed twice weekly for 24 months. Diarrheal and monthly surveillance stool samples were tested for Cryptosporidium by enzyme-linked immunosorbent assay. Socioeconomic data were collected by survey, and anthropometry was measured monthly. Results: Sixty-five percent (962/1486) of children had a Cryptosporidium infection and 54% (802/1486) had at least 1 Cryptosporidium-associated diarrheal episode. Cryptosporidium diarrhea was more likely to be associated with dehydration (16.5% vs 8.3%, P < .01). Rates of Cryptosporidium diarrhea were highest in the Peru (10.9%) and Pakistan (9.2%) sites. In multivariable regression analysis, overcrowding at home was a significant risk factor for infection in the Bangladesh site (odds ratio, 2.3 [95% confidence interval {CI}, 1.2-4.6]). Multiple linear regression demonstrated a decreased length-for-age z score at 24 months in Cryptosporidium-positive children in the India (ß = -.26 [95% CI, -.51 to -.01]) and Bangladesh (ß = -.20 [95% CI, -.44 to .05]) sites. Conclusions: This multicountry cohort study confirmed the association of Cryptosporidium infection with stunting in 2 South Asian sites, highlighting the significance of cryptosporidiosis as a risk factor for poor growth. We observed that the rate, age of onset, and number of repeat infections varied per site; future interventions should be targeted per region to maximize success.
Asunto(s)
Criptosporidiosis/epidemiología , Diarrea/epidemiología , Áreas de Pobreza , África/epidemiología , Asia/epidemiología , Preescolar , Estudios de Cohortes , Aglomeración , Cryptosporidium/aislamiento & purificación , Diarrea/parasitología , Heces/parasitología , Femenino , Trastornos del Crecimiento/parasitología , Humanos , Lactante , Recién Nacido , Masculino , Desnutrición/parasitología , Análisis de Regresión , Factores de Riesgo , Factores Socioeconómicos , América del Sur/epidemiología , Encuestas y CuestionariosRESUMEN
Schistosomiasis and malnutrition are often overlapped in poor communities, resulting in disproportionately high mortality rates. Currently, fragmented data make it difficult to define the relationship between diet and schistosomiasis. Thus, we systematically review the preclinical evidence on the impact of diet in Schistosoma mansoni infection. From a structured search, we recovered 27 original articles. All studies used mice and most of them investigated hypoproteic (70.37%), hyperlipidic (22.22%) or vitamin-deficient (7.41%) diets. Diets based on carbohydrate, zinc or milk supplementation were investigated at a reduced frequency (3.70% each). Hypoproteic diets attenuated parasitic load and granulomatous inflammation, but also reduced host resistance to S. mansoni infection, determining higher mortality rates. By stimulating steatohepatitis, parasitic load and granulomatous inflammation, hyperlipidic diets increase organ damage and mortality in infected animals. Although a high-sugar diet and vitamin restriction potentiate and zinc supplementation attenuates S. mansoni infection, the current evidence for these diets remains inconclusive. Analysis of methodological quality indicated that the current evidence is at high risk of bias due to incomplete characterization of the experimental design, diet composition and treatment protocols. From the bias analysis, we report methodological limitations that should be considered to avoid systematic reproduction of inconsistent and poorly reproducible experimental designs.
Asunto(s)
Dieta , Desnutrición/parasitología , Esquistosomiasis mansoni/fisiopatología , Animales , Dieta Alta en Grasa , Humanos , Inflamación/patología , Hígado/parasitología , Ratones , Ratas , Esquistosomiasis mansoni/prevención & control , Vitaminas/administración & dosificación , Zinc/administración & dosificaciónRESUMEN
BACKGROUND: Ascaris lumbricoides infections are one of the commonnest intestinal nematode infections in the world, with a profound negative effect on nutritional status among underprivileged populations. In Sri Lanka, Ascaris infections and low nutritional status still persist in the plantation sector. However, research regarding the association between Ascaris infections and nutritional status is scarce. The main purpose of this study was to determine the association between Ascaris infections and physical growth among children in a plantation sector in Sri Lanka. METHODS: A cross sectional study was conducted among 489 children aged between 1 and 12 years ina plantation sector, Sri Lanka, from January to April 2013. Anthropometric measurements were collected to assess height-for-age (HAZ), weight-for-age (WAZ) and weight-for-height (WHZ) to determine stunting, underweight and wasting respectively. Data on socio-demographic and antihelminthic treatment were ascertained using an interviewer administrated structured questionnaire. Stool samples were subjected to wet mount preparation followed byformaldehyde-ether sedimentation technique to diagnose Ascaris infection and a Kato Katz technique was performed to determine the eggs intensity. AnthroPlus, EpiInfo and SPSS software was used to analyze data. RESULTS: Of the study sample, 38.4% showed Ascaris lumbricoides infections. Light intensity infections (51%) were common in the infected children, followed by moderate (30%) and heavy (19%) infections. Prevalence of Ascaris infections was significantly associated with de-worming more than six months prior to the study. Prevalence of undernutrition among children was 61.7%. Forty-five per cent were underweight, while 24.1% and 21.5% of children were stunted and wasted respectively. However, no significant association was found between Ascaris infections status and undernutrition. Meanwhile, heavy intensity infections were associated with decreased values of WHZ (p = 0.020). CONCLUSIONS: Ascaris infections and undernutrition are still highly prevalent and a major public health problem in the plantation sector in Sri Lanka. Health and nutrition intervention programs should be implemented to increase the nutritional status of children.
Asunto(s)
Ascariasis/epidemiología , Ascaris lumbricoides/aislamiento & purificación , Trastornos del Crecimiento/epidemiología , Desnutrición/epidemiología , Síndrome Debilitante/epidemiología , Agricultura , Animales , Ascariasis/complicaciones , Ascariasis/diagnóstico , Niño , Preescolar , Estudios Transversales , Femenino , Trastornos del Crecimiento/complicaciones , Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/parasitología , Humanos , Lactante , Masculino , Desnutrición/complicaciones , Desnutrición/diagnóstico , Desnutrición/parasitología , Prevalencia , Índice de Severidad de la Enfermedad , Sri Lanka/epidemiología , Té , Síndrome Debilitante/complicaciones , Síndrome Debilitante/diagnóstico , Síndrome Debilitante/parasitologíaRESUMEN
Diverse enteropathogen exposures associate with childhood malnutrition. To elucidate mechanistic pathways whereby enteric microbes interact during malnutrition, we used protein deficiency in mice to develop a new model of co-enteropathogen enteropathy. Focusing on common enteropathogens in malnourished children, Giardia lamblia and enteroaggregative Escherichia coli (EAEC), we provide new insights into intersecting pathogen-specific mechanisms that enhance malnutrition. We show for the first time that during protein malnutrition, the intestinal microbiota permits persistent Giardia colonization and simultaneously contributes to growth impairment. Despite signals of intestinal injury, such as IL1α, Giardia-infected mice lack pro-inflammatory intestinal responses, similar to endemic pediatric Giardia infections. Rather, Giardia perturbs microbial host co-metabolites of proteolysis during growth impairment, whereas host nicotinamide utilization adaptations that correspond with growth recovery increase. EAEC promotes intestinal inflammation and markers of myeloid cell activation. During co-infection, intestinal inflammatory signaling and cellular recruitment responses to EAEC are preserved together with a Giardia-mediated diminishment in myeloid cell activation. Conversely, EAEC extinguishes markers of host energy expenditure regulatory responses to Giardia, as host metabolic adaptations appear exhausted. Integrating immunologic and metabolic profiles during co-pathogen infection and malnutrition, we develop a working mechanistic model of how cumulative diet-induced and pathogen-triggered microbial perturbations result in an increasingly wasted host.
Asunto(s)
Coinfección/microbiología , Coinfección/parasitología , Infecciones por Escherichia coli/microbiología , Escherichia coli/fisiología , Giardia lamblia/fisiología , Giardiasis/parasitología , Desnutrición/microbiología , Desnutrición/parasitología , Animales , Niño , Coinfección/inmunología , Citocinas/inmunología , Modelos Animales de Enfermedad , Infecciones por Escherichia coli/inmunología , Giardiasis/inmunología , Humanos , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Mucosa Intestinal/parasitología , Masculino , Desnutrición/inmunología , Ratones , Ratones Endogámicos C57BL , Células Mieloides/inmunologíaRESUMEN
Background: Early exposure to enteropathogens has been associated with malnutrition in children in low-resource settings. However, the contribution of individual enteropathogens remains poorly defined. Molecular diagnostics offer an increase in sensitivity for detecting enteropathogens but have not been comprehensively applied to studies of malnutrition.Objective: We sought to identify enteropathogens associated with malnutrition in Bangladesh.Design: Malnourished children [weight-for-age z score (WAZ) <-2] aged 6-23 mo in Dhaka, Bangladesh, and identified by active community surveillance were enrolled as cases, and normal-weight children (WAZ >-1) of the same age and from the same community were enrolled as controls. Stools were collected at enrollment and, for cases, after a 5-mo nutritional intervention. Enrollment and follow-up stools were tested by quantitative polymerase chain reaction for 32 enteropathogens with the use of a custom-developed TaqMan Array Card.Results: Enteropathogen testing was performed on 486 cases and 442 controls upon enrollment and 365 cases at follow-up. At enrollment, the detection of enteroaggregative Escherichia coli (OR: 1.39; 95% CI: 1.05, 1.83), Campylobacter spp. (OR: 1.46; 95% CI: 1.11, 1.91), heat-labile enterotoxin-producing E. coli (OR: 1.55; 95% CI: 1.04, 2.33), Shigella/enteroinvasive E. coli (OR: 1.65; 95% CI: 1.10, 2.46), norovirus genogroup I (OR: 1.66; 95% CI: 1.23, 2.25), and Giardia (OR: 1.73; 95% CI: 1.20, 2.49) were associated with malnourished cases, and the total burden of these pathogens remained associated with malnutrition after adjusting for sociodemographic factors. The number of these pathogens at follow-up was negatively associated with the change in WAZ during the intervention (-0.10 change in WAZ per pathogen detected; 95% CI: -0.14, -0.06), whereas the number at enrollment was positively associated with the change in WAZ (0.05 change in WAZ per pathogen detected; 95% CI: 0.00, 0.10).Conclusions: A subset of enteropathogens was associated with malnutrition in this setting. Broad interventions designed to reduce the burden of infection with these pathogens are needed. This trial was registered at clinicaltrials.gov as NCT02441426.
Asunto(s)
Campylobacter , Trastornos de la Nutrición del Niño/etiología , Escherichia coli , Giardia , Desnutrición/etiología , Norovirus , Shigella , Bangladesh , Peso Corporal , Campylobacter/genética , Campylobacter/patogenicidad , Estudios de Casos y Controles , Trastornos de la Nutrición del Niño/microbiología , Trastornos de la Nutrición del Niño/parasitología , Trastornos de la Nutrición del Niño/virología , Preescolar , Diarrea/etiología , Diarrea/microbiología , Diarrea/parasitología , Diarrea/virología , Escherichia coli/genética , Escherichia coli/patogenicidad , Femenino , Giardia/genética , Giardia/patogenicidad , Humanos , Lactante , Masculino , Desnutrición/microbiología , Desnutrición/parasitología , Desnutrición/virología , Norovirus/genética , Norovirus/patogenicidad , Reacción en Cadena de la Polimerasa , Shigella/genética , Shigella/patogenicidadRESUMEN
Protein malnutrition, the most deleterious cause of malnutrition in developing countries, has been considered a primary risk factor for the development of clinical visceral leishmaniasis (VL). Protein malnutrition and infection with Leishmania infantum leads to lymphoid tissue disorganization, including changes in cellularity and lymphocyte subpopulations in the thymus and spleen. Here we report that protein malnutrition modifies thymic chemotactic factors by diminishing the CCL5, CXCL12, IGF1, CXCL9 and CXCL10 protein levels in infected animals. Nevertheless, T cells preserve their migratory capability, as they were able to migrate ex vivo in response to chemotactic stimuli, indicating that malnutrition may compromise the thymic microenvironment and alter in vivo thymocyte migration. Decrease in chemotactic factors protein levels was accompanied by an early increase in the parasite load of the spleen. These results suggest that the precondition of malnutrition is affecting the cell-mediated immune response to L. infantum by altering T cell migration and interfering with the capacity of protein-deprived animals to control parasite spreading and proliferation. Our data provide evidence for a disturbance of T lymphocyte migration involving both central and peripheral T-cells, which likely contribute to the pathophysiology of VL that occurs in malnourished individuals.
Asunto(s)
Movimiento Celular , Leishmania infantum/patogenicidad , Leishmaniasis Visceral/complicaciones , Leishmaniasis Visceral/inmunología , Desnutrición/complicaciones , Desnutrición/inmunología , Linfocitos T/patología , Timo/patología , Animales , Apoptosis , Atrofia , Peso Corporal , Quimiotaxis , Citocinas/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Leishmaniasis Visceral/sangre , Leishmaniasis Visceral/parasitología , Leptina/sangre , Ligandos , Macrófagos/metabolismo , Macrófagos/patología , Desnutrición/sangre , Desnutrición/parasitología , Ratones Endogámicos BALB C , Carga de Parásitos , Parásitos/patogenicidad , Receptores CXCR3/metabolismo , Bazo/parasitología , Timocitos/patologíaRESUMEN
Techniques for Giardia diagnosis based on microscopy are usually applied as routine laboratory testing; however, they typically exhibit low sensitivity. This study aimed to evaluate Giardia duodenalis and other intestinal parasitic infections in different pediatric groups, with an emphasis on the comparison of Giardia diagnostic techniques. Feces from 824 children from different groups (diarrheic, malnourished, with cancer and from day care) were examined by microscopy and ELISA for Giardia, Cryptosporidium sp. and Entamoeba histolytica coproantigen detection. Giardia-positive samples from day-care children, identified by either microscopy or ELISA, were further tested by PCR targeting of the ß-giardin and Gdh genes. Statistically significant differences (P<0.05) were observed when comparing the frequency of each protozoan among the groups. Giardia duodenalis was more frequent in day-care children and Cryptosporidium sp. in diarrheic and malnourished groups; infections by Entamoeba histolytica were found only in children with diarrhea. Considering positivity for Giardia by at least one method, ELISA was found to be more sensitive than microscopy (97% versus 55%). To examine discrepancies among the diagnostic methods, 71 Giardia-positive stool samples from day-care children were tested by PCR; of these, DNA was amplified from 51 samples (77.4%). Concordance of positivity between microscopy and ELISA was found for 48 samples, with 43 confirmed by PCR. Parasite DNA was amplified from eleven of the 20 Giardia samples (55%) identified only by ELISA. This study shows the higher sensitivity of ELISA over microscopy for Giardia diagnosis when a single sample is analyzed and emphasizes the need for methods based on coproantigen detection to identify this parasite in diarrheic fecal samples.
Asunto(s)
Criptosporidiosis/diagnóstico , Entamebiasis/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Giardiasis/diagnóstico , Parasitosis Intestinales/diagnóstico , Microscopía/métodos , Niño , Guarderías Infantiles , Criptosporidiosis/parasitología , Cryptosporidium/aislamiento & purificación , Proteínas del Citoesqueleto/genética , ADN Protozoario/genética , Diarrea/parasitología , Entamoeba histolytica/aislamiento & purificación , Entamebiasis/parasitología , Heces/parasitología , Femenino , Giardia lamblia/aislamiento & purificación , Giardiasis/parasitología , Humanos , Parasitosis Intestinales/parasitología , Masculino , Desnutrición/parasitología , Proteínas Protozoarias/genética , Sensibilidad y Especificidad , Deshidrogenasas del Alcohol de Azúcar/genéticaRESUMEN
Malnutrition induces a state of growth retardation and immunologic depression, enhancing the host susceptibility to various infections. In the present study, it was observed that prebiotic supplementation either prior or simultaneously with Giardia infection in malnourished mice significantly reduced the severity of giardiasis and increased the body and small intestine mass, along with increased lactobacilli counts in faeces compared with malnourished-Giardia-infected mice. More specifically, prebiotic supplementation significantly increased the levels of anti-giardial IgG and IgA antibodies and anti-inflammatory cytokines IL-6 and IL-10 and reduced the pro-inflammatory cytokine TNF-α, along with increased levels of nitric oxide in both the serum and intestinal fluid of malnourished-prebiotic-Giardia-infected mice compared with malnourished-Giardia-infected mice. Histopathology and scanning electron microscopy of the small intestine also revealed less cellular and mucosal damage in the microvilli of prebiotic-supplemented malnourished-Giardia-infected mice compared with severely damaged mummified and blunted villi of malnourished-Giardia-infected mice. This is the first study to report that prebiotic supplementation modulated the gut morphology and improved the immune status even in malnourished-Giardia-infected mice.
Asunto(s)
Giardia/fisiología , Giardiasis/inmunología , Inulina/administración & dosificación , Desnutrición/inmunología , Prebióticos/administración & dosificación , Animales , Suplementos Dietéticos/análisis , Heces/parasitología , Femenino , Giardia/inmunología , Giardiasis/parasitología , Humanos , Interleucina-10/inmunología , Interleucina-6/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/parasitología , Intestino Delgado/inmunología , Intestino Delgado/parasitología , Masculino , Desnutrición/parasitología , Ratones , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Innate lymphoid cells (ILC) play an important role in many immune processes, including control of infections, inflammation, and tissue repair. To date, little is known about the metabolism of ILC and whether these cells can metabolically adapt in response to environmental signals. Here we show that type 2 innate lymphoid cells (ILC2), important mediators of barrier immunity, predominantly depend on fatty acid (FA) metabolism during helminth infection. Further, in situations where an essential nutrient, such as vitamin A, is limited, ILC2 sustain their function and selectively maintain interleukin 13 (IL-13) production via increased acquisition and utilization of FA. Together, these results reveal that ILC2 preferentially use FAs to maintain their function in the context of helminth infection or malnutrition and propose that enhanced FA usage and FA-dependent IL-13 production by ILC2 could represent a host adaptation to maintain barrier immunity under dietary restriction.
Asunto(s)
Ácidos Grasos/inmunología , Helmintiasis/inmunología , Inmunidad Innata , Linfocitos/inmunología , Desnutrición/inmunología , Animales , Helmintiasis/genética , Helmintiasis/parasitología , Interleucina-13/inmunología , Desnutrición/genética , Desnutrición/parasitología , Ratones , Ratones NoqueadosRESUMEN
BACKGROUND: Lysine requirements of well-nourished children from developing regions have been found to be similar to those of children from developed regions (33.5 mg · kg⻹ · d⻹). However, intestinal parasites have been shown to increase lysine requirements in undernourished adults, and it is not known if a similar phenomenon occurs in undernourished children from poor and unsanitary environments. OBJECTIVE: Our objective was to measure the lysine requirement of moderately undernourished school-aged Indian children by the indicator amino acid oxidation technique before and after successful treatment for intestinal parasites. METHODS: Twenty-one undernourished school-aged children (â¼8 y of age) with z scores between -2 SD and -3 SD for height-for-age or weight-for-age, who tested positive for intestinal parasites, were studied before and after successful antiparasite treatment. Children were fed any 2 of 7 levels of lysine intakes (5, 15, 25, 35, 50, 65, and 80 mg · kg⻹ · d⻹) in random order. The lysine requirement was determined by applying a 2-phase linear regression crossover analysis on the fractional oxidation rate of the tracer L-[1-¹³C] phenylalanine in response to the graded lysine intakes. RESULTS: The lysine requirement of undernourished children with intestinal parasite infestations was determined to be 42.8 mg · kg⻹ · d⻹ (95% CI: 32.6, 53.1 mg · kg⻹ · d⻹), and after successful antiparasitic treatment it was determined to be 35.5 mg · kg⻹ · d⻹ (95% CI: 25.5, 45.5 mg · kg⻹ · d⻹). The results were significantly different (P < 0.05), although the 95% CIs overlapped. CONCLUSIONS: The lysine requirement in undernourished children is similar to that of well-nourished children, and intestinal parasitic infestation increased the lysine requirement by â¼20%.
Asunto(s)
Fenómenos Fisiológicos Nutricionales Infantiles , Parasitosis Intestinales/complicaciones , Lisina/administración & dosificación , Desnutrición/metabolismo , Necesidades Nutricionales , Fenilalanina/metabolismo , Antiparasitarios/uso terapéutico , Estatura , Peso Corporal , Isótopos de Carbono , Niño , Desarrollo Infantil , Países en Desarrollo , Femenino , Humanos , India/epidemiología , Técnicas de Dilución del Indicador , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Lisina/metabolismo , Masculino , Desnutrición/complicaciones , Desnutrición/parasitología , Desnutrición/fisiopatología , Oxidación-Reducción , Fenilalanina/administración & dosificación , Áreas de Pobreza , Prevalencia , Índice de Severidad de la EnfermedadRESUMEN
A 10-year-old child presented with dull aching periumbilical abdominal pain for 15 days. The child was not gaining weight despite a good appetite. Physical examination of the child revealed grade-I protein energy malnourishment (PEM) according to IAP (Indian Academic of Paediatrics) classification. The rest of the systemic examination was normal. Routine blood investigation revealed anaemia with eosinophilia. Abdominal ultrasonography did not show any abnormality with curvilinear transducer (3.5-5 MHz), however, linear ultrasound transducer (7.5-12 MHz) with harmonic tissue imaging showed worms in the lumen of the small intestine with curling movement on real time scanning. Stool examination for the eggs of ascariasis was positive. The patient was treated with antihelminthic drugs. Dietary modification for the PEM was advised. After 3 months of treatment, the patient improved and stool examination for Ascaris was negative on follow-up.
Asunto(s)
Dolor Abdominal/etiología , Albendazol/administración & dosificación , Antihelmínticos/administración & dosificación , Ascariasis/diagnóstico , Ascaris lumbricoides/aislamiento & purificación , Heces/parasitología , Desnutrición/etiología , Dolor Abdominal/parasitología , Dolor Abdominal/patología , Animales , Ascariasis/tratamiento farmacológico , Ascariasis/patología , Niño , Suplementos Dietéticos , Humanos , Hallazgos Incidentales , Desnutrición/tratamiento farmacológico , Desnutrición/parasitología , Resultado del TratamientoRESUMEN
Visceral leishmaniasis (VL) is a parasitic infectious disease that causes significant morbidity and mortality in the tropical and subtropical regions of the world. Although infections with visceralizing Leishmania may be asymptomatic, factors such as undernutrition increase the likelihood of progressing to clinical disease. Protein malnutrition, the most deleterious cause of malnutrition in developing countries, has been considered as a primary risk factor for the development of clinical VL. However, data regarding the immunological basis of this association are scarce. With the aim to analyze the effects of protein malnutrition on Leishmania infantum infection, we used BALB/c mice subjected to control or low protein isocaloric diets. Each animal group was divided into two subgroups and one was infected with L. infantum resulting in four study groups: animals fed 14% protein diet (CP), animals fed 4% protein diet (LP), animals fed 14% protein diet and infected (CPi), and animals fed 4% protein diet and infected (LPi).The susceptibility to L. infantum infection and immune responses were assessed in terms of body and lymphoid organ weight, parasite load, lymphocyte subpopulations, and cytokine expression. LPi mice had a significant reduction of body and lymphoid organ weight and exhibited a severe decrease of lymphoid follicles in the spleen. Moreover, LPi animals showed a significant decrease in CD4+CD8+ T cells in the thymus, whereas there was an increase of CD4+ and CD8+ T cells percentages in the spleen. Notably, the cytokine mRNA levels in the thymus and spleen of protein malnourished-infected animals were altered compared to the CP mice. Protein malnutrition results in a drastic dysregulation of T cells and cytokine expression in the thymus and spleen of L. infantum-infected BALB/c mice, which may lead to defective regulation of the thymocyte population and an impaired splenic immune response, accelerating the events of a normal course of infection.