Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 377
Filter
1.
Rev. medica electron ; 43(3): 616-628, 2021. tab
Article in Spanish | LILACS, CUMED | ID: biblio-1289808

ABSTRACT

RESUMEN Introducción: la infección por Helicobacter pylori es la enfermedad bacteriana crónica que afecta con mayor prevalencia al ser humano. Objetivo: identificar la frecuencia de infección por Helicobacter pylori y su relación con variables consideradas factores de riesgo de esta infección. Materiales y métodos: estudio de corte transversal realizado en el Policlínico Docente Camilo Cienfuegos, del municipio Habana del Este, durante el año 2018, en un universo de 42 pacientes con 18 años y más de edad, con sospecha clínica y hallazgo endoscópico de úlcera duodenal e informe del resultado de estudio histológico para el diagnóstico de la infección. Se confeccionó una planilla de recolección de datos que incluyó variables como hacinamiento, agua de consumo, lugar de nacimiento, estancia en una institución, contacto con animales y antecedentes familiares. Se determinó relación entre variables con la prueba de chi cuadrado (c2) con significación estadística ɒ = 0,05, y se identificaron variables cuyos coeficientes fueron significativamente diferentes de 0 (p < 0,05). La fuerza de asociación se determinó mediante odds ratio. Resultados: la prevalencia fue de 59,5 %. Se encontró asociación estadística y constituyeron factores de riesgo de infección por Helicobacter pylori, el hacinamiento (c2 = 4,37; OR = 3,89), el agua de consumo (c2 = 4,92; OR = 3,43), el contacto con animales (c2 = 7,41; OR = 6,17) y los antecedentes familiares (c2 = 13,18; OR = 13). Conclusiones: el estudio permitió determinar la prevalencia de infección por Helicobacter pylori y las principales variables asociadas, coincidiendo con otros estudios revisados que tratan el tema (AU).


ABSTRACT Introduction: the infection by Helicobacter pylori is the chronic bacterial disease that affects the human being with greater prevalence. Objective: to identify the frequency of the infection by Helicobacter pylori and its relationship with variables considered risk factors for this infection. Materials and methods: a cross-sectional study was carried out in the teaching Polyclinic Camilo Cienfuegos, municipality Habana del Este, during 2018. In a universe of 42 patients aged 18 years and over, with clinical suspicion and endoscopic diagnosis of duodenal ulcer and histological study report for the diagnosis of the infection. A data collection form was made, which included variables such as: overcrowding, consumption water, place of birth, staying in an institution, contact with animals, and family history. The relationship within variables was found using the chi-square test (c2) with statistical significance ɒ = 0.05, and there were identified variables significantly different from 0 (p < 0.05). The association strength was determined through odds ratio. Results: the prevalence was 59.5%. Statistical association was found and overcrowding (c2 = 4.37, OR = 3.89), consumption water (c2 = 4.92; OR = 3.43), contact with animals (c2 = 7.41, OR = 6.17) and family history (c2 = 13.18, OR = 13) were found risk factors for Helicobacter pylori infection. Conclusions: the study allowed to determine the prevalence of Helicobacter pylori infection and the main associated variables, coinciding with other reviewed studies dealing with the subject (AU).


Subject(s)
Humans , Male , Female , Helicobacter pylori/virology , Duodenal Ulcer/diagnosis , Signs and Symptoms , Prevalence , Risk Factors , Helicobacter pylori/pathogenicity , Virulence Factors/physiology
2.
Cienc. tecnol. salud ; 8(1): 82-92, 2021. il 27 c
Article in Spanish | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1352960

ABSTRACT

Se determinó la respuesta inmunológica a proteínas recombinantes de Helicobacter pylori en pacientes dis-pépticos (adultos y niños), pacientes con cáncer gástrico y sus familiares asintomáticos adultos viviendo con ellos. Se utilizó la prueba recomLine® Helicobacter IgG e IgA, y con base en el reconocimiento de los factores de virulencia VacA y CagA se determinó si la cepa de H. pylori era de tipo I o II. El análisis de los datos fue descriptivo y analítico y se estimaron los intervalos de confianza de 95%, con un nivel de error de 0.05 y Odds ratio. El 58.7% (121/206) de los pacientes presentó la bacteria en tinción histológica de biopsia, positividad que disminuyó con la edad y daño histológico. La frecuencia de la respuesta a los anticuerpos IgG fue mayor que IgA, en ambos casos ésta fue menor en los niños. Las proteínas del H. pylori más reconocidas tanto por IgA como IgG fueron VacA y CagA, y la respuesta a las otras proteínas investigadas fue mayor al aumentar el daño histológi-co. La cepa tipo I fue la que predominó en la población en estudio con 66% (136/206). Se deben continuar con los estudios de prevalencia de la cepa tipo I del H. pylori y del reconocimiento de sus antígenos en la población guatemalteca a fin de determinar su utilidad en el diagnóstico y pronóstico de la infección.


The immune response to recombinant Helicobacter pylori proteins was determined in dyspeptic patients (adults and children), patients with gastric cancer and their asymptomatic adults' relatives living with them. The recomLine® Helicobacter IgG and IgA test was used and based on the recognition of the virulence factors VacA and CagA, it was determined whether the H. pylori strain was type I or II. The data analysis was descriptive and analytic, and 95% confidence intervals were estimated, with an error level of 0.05, and Odds ratio. The patients that presented the bacterium in histological biopsy were 58.7% (121/206), positivity that decreased with age and histological damage. The frecuency of response to IgG antibodies was higher than IgA, in both cases it was lower in children. VacA and CagA were the H. pylori proteins most recognized by both IgA and IgG and it was observed that the number of recognized proteins was greater with increasing histological damage. The type I strain was the one that predominated in the study population 66% (136/206). Prevalence studies of the type I strain of H. pylori ant the recognition of its antigens in the Guatemalan population should continue in order to determine its usefulness in the diagnosis and prognosis of infection.


Subject(s)
Humans , Child , Adult , Stomach Neoplasms/immunology , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Helicobacter pylori/immunology , Dyspepsia/immunology , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology , Biopsy , Recombinant Proteins/analysis , Recombinant Proteins/immunology , Immunoglobulin A/analysis , Immunoglobulin G/analysis , Helicobacter pylori/isolation & purification , Helicobacter pylori/pathogenicity , Dyspepsia/microbiology , Dyspepsia/pathology , Guatemala
3.
Rev. méd. hondur ; 89(1): 10-16, 2021. tab
Article in Spanish | LILACS | ID: biblio-1282992

ABSTRACT

Antecedentes: Las recomendaciones de esquemas para erradicar Helicobacter pylori se encuentran ampliamente dis- ponibles. Este es un patógeno de alta prioridad para búsqueda y desarrollo de nuevos y efectivos tratamientos. Objetivo: Descri- bir la respuesta terapéutica con terapia de rescate para infección por H. pylori, Hospital Escuela, Tegucigalpa, diciembre 2016-abril 2017. Métodos: Estudio descriptivo longitudinal retrospectivo en pacientes consecutivos con sintomatología gastrointestinal e in- fección conirmada por H. pylori. Mediante el registro del Servi- cio de Gastroenterología, Departamento de Medicina Interna, se identiicaron pacientes positivos por H. pylori. Se registraron datos sociodemográicos, clínicos y diagnósticos. El tratamiento de res- cate brindado fue, vía oral por 10 días: levoloxacina 500 mg/día, esomeprazol 40 mg dos veces/día, amoxicilina 1 gr dos veces/ día. La conirmación de la erradicación fue realizada 4-8 semanas postratamiento. Se registró información sobre la adherencia al tra- tamiento y los efectos secundarios. Resultados: Se analizaron 30 casos; 56.7% (17) pacientes nuevos y 43.3% (13) pacientes con al menos un fracaso. En el 16.0% (5) no hubo conirmación de erra- dicación; se obtuvo una tasa de erradicación del 72.0% (18/25), IC95% 50.6-87.9; siendo 78.5% (11/14) en pacientes nuevos ver- sus 63.6% (7/11) en fracasos previos, IC95% -9.6-54.0, p=0.318. Discusión: La tasa de erradicación en este grupo de pacientes no fue satisfactoria. Actualmente el tratamiento con levoloxacina es recomendado como terapia de segunda línea o de rescate en regiones con baja o alta resistencia a la claritromicina, aunque la resistencia a quinolonas ha aumentado en los últimos años en va- rios países...(AU)


Subject(s)
Humans , Adult , Helicobacter pylori/pathogenicity , Gastrointestinal Diseases/complications , Levofloxacin/therapeutic use , Amoxicillin/therapeutic use
4.
Rev. medica electron ; 42(5): 2301-2313, sept.-oct. 2020. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1144735

ABSTRACT

RESUMEN Introducción: la infección por Helicobacter pylori es una de las más prevalentes en el planeta. Supone una carga significativa para los sistemas sanitarios, debido a la elevada resistencia a antibióticos que presenta para su erradicación. Objetivo: determinar las características clínico epidemiológicas de infección por Helicobacter pylori de pacientes atendidos en Consulta Provincial de Gastroenterología. Materiales y métodos: se realizó un estudio observacional descriptivo. El universo estuvo conformado por los 167 pacientes con determinación de Helicobacter pylori positivo, por test de ureasa. Las variables a considerar fueron: la edad, el sexo, diagnóstico histológico, síntomas clínicos y la evolución clínica posterior al tratamiento específico para Helicobacter pylori. Se utilizó la técnica estadística de análisis de distribución de frecuencias. Resultados: un 59,6 % de los pacientes resultó con Helicobacter pylori positivo con predominio del sexo masculino. Fue la gastritis crónica la alteración gástrica que más se asoció a la infección. La epigastralgia y distensión abdominal resultaron los síntomas más frecuentes. Evolucionaron de forma satisfactoria el 49 % de los casos y solo un 17 % presentaron una mala respuesta al tratamiento. Conclusiones: se obtuvo un alto porcentaje de infección por Helicobacter pylori y una buena respuesta al tratamiento utilizado (AU).


ABSTRACT Introduction: the infection for Helicobacter pylori is one of the more prevalent in the world; it supposes a significant burden for the sanitary systems, due to the high resistance to antibiotics that it presents for its eradication. Objective: to determine the clinical epidemiological characteristics of the infection due to Helicobacter pylori in patients treated in the provincial consultation of Gastroenterología. Materials and methods: an observational, descriptive study was carried out in a universe formed by 167 patients with positive Helicobacter pylori determined by urease test. The variables to consider were age, sex, histologic diagnosis, clinical symptoms and clinical evolution after the specific treatment for Helicobacter pylori. The statistical technique of analysis of frequencies distribution was used. Results: 59, 6% of the patients was Helicobacter pylori positive with prevalence of the male sex; chronic gastritis was the gastric alteration more associated to the infection. Epigastralgia and abdominal distension were the most frequent symptoms. 49% of the cases evolved in a satisfactory way and only 17% answered bad to the treatment. Conclusions: a high percent of infection by Helicobacter pylori was found and also a good answer to the used treatment (AU).


Subject(s)
Humans , Male , Female , Helicobacter pylori/pathogenicity , Gastroenterology/methods , Patients , Pathological Conditions, Signs and Symptoms , Gastritis/complications , Infections/complications , Infections/parasitology , Anti-Bacterial Agents
5.
Electron. j. biotechnol ; 45: 53-59, May 15, 2020. tab, ilus
Article in English | LILACS | ID: biblio-1177447

ABSTRACT

BACKGROUND: Helicobacter pylori is a chronic pathogenic bacteria that causes gastric mucosal damage through various host-related and pathogen-related factors. Thus, a single gene research cannot fully explain its pathogenicity. PURPOSE OF STUDY: It is necessary to establish a Helicobacter pylori pathogenic gene transcription factor regulatory network (TFRN) and study its central nodes. RESULTS: The expression data of Helicobacter pylori pathogenic genes were obtained through GEO Datasets of NCBI. The genes were screened using linear model-empirical Bayesian statistics in R language Limma package combined with the conventional t-test; the results identified 1231 differentially expressed genes. The functional analysis (gene ontology-analysis) and signal pathway analysis (pathway-analysis) of differentially expressed genes were performed using the DAVID and KEGG databases, respectively. The pathogenic gene regulatory network was constructed by integrating transcriptional regulatory element database (TRED); the disease-related analysis of the pathogenic genes was conducted using the DAVID annotation tool. Five pathogenic genes (Nos2, Il5, Colla1, Tnf, and Nfkb1) and their transcription factors (Jun, Cebpa, Egrl, Ppara, and Il6) were found to suppress the host immune function and enhance the pathogenicity of Helicobacter pylori by regulating the host immune system. CONCLUSIONS: This effect was largely mediated via three signaling pathways: Tnf pathway, PI3K Akt pathway, and Jak­STAT pathway. The pathogenicity of Helicobacter pylori is closely related to the body's immune and inflammatory system. A better understanding of the correlation of the pathogenic factors with the host immune and inflammatory factors may help to determine the precise pathogenic mechanism of H. pylori infection.


Subject(s)
Helicobacter pylori/genetics , Helicobacter pylori/pathogenicity , Computational Biology , Transcription Factors , Cytokines , Virulence Factors , Gastritis/immunology , Gastritis/microbiology , Genes, Bacterial , Immune System , Inflammation
6.
Rev. Hosp. Clin. Univ. Chile ; 30(1): 3-11, 2019. Tab., Graf.
Article in Spanish | LILACS | ID: biblio-1005532

ABSTRACT

Helicobacter pylori (HP) is the most widely chronic human infection around the world, and the main risk factor for the development of gastric cancer. Our country has high rates of this neoplasia and a high prevalence of HP infection. Even both have fallen in the last year, is a major concern to diagnose the population infected with HP in early stages, before the development of premalignant lesions and properly eradicate this infection. In this review, we discussed the different methods for the diagnosis of HP and factors that change positivity as the use of proton pump inhibitors. Also, we discussed the factors to be considered in the choice of the treatment, like local resistance to antibiotics, specially clarithromycin. In the last years has been documented in Chile a significant increase in resistance to clarithromycin, from 20 to 46%, which predicts inadequate effectiveness for the classic triple therapy. As the result of the previous analysis we discussed new possible therapies, including bismuth quadruple therapy and concomitant therapy. (AU)


Subject(s)
Humans , Male , Female , Helicobacter pylori , Helicobacter pylori/pathogenicity , Helicobacter Infections/diagnosis , Helicobacter Infections/therapy , Helicobacter Infections/epidemiology
7.
Gastroenterol. latinoam ; 30(supl.1): S18-S25, 2019. ilus, tab, graf
Article in Spanish | LILACS | ID: biblio-1116305

ABSTRACT

Helicobacter pylori (H. pylori) is a gram negative bacteria that survives in the gastric acid environment. The infection is acquired mainly during childhood. Fifty to 70% of adult population has the infection. However, in the last 10 year, a decrease in the prevalence of this infection has been observed in all age groups, in particular in pediatric population and elderly patients over 60 years old. The evolution of the infection depends on bacterial factors (virulence and toxins) and host immune response. People infected mainly develop gastrointestinal diseases such as gastritis, peptic ulcer and MALT lymphoma. H. pylori infection is the main risk factor of gastric cancer and for that reason, the eradication is recommended if H. pylori has been detected through invasive or non-invasive tests. Among children, eradication is not recommended unless there is a clinical manifestation that merits. H. pylori eradication is recommended in symptomatic adults and there is a controversy about massive eradication in asymptomatic population due to the risk of development of antibiotic resistance. Treatment is based on the use of proton pump inhibitors (PPI) associated to antibiotics, that should be chosen taking into account the increasing antibiotic resistance, and local availability. Clarithromycin (CLA) and levofloxacin resistance is increasingly high, and CLA-free quadruple therapy schemes are currently recommended for first-line therapy. H. pylori eradication must be confirmed with invasive or non-invasive tests. Second-line therapy based on antibiotics not previously used, PPI high doses and bismuth is recommended.


Helicobacter pylori (H. pylori) es una bacteria gramnegativa que sobrevive en el medio ácido gástrico. La infección se adquiere principalmente en la niñez. Un 50 a 70% de la población adulta es portadora, pero en los últimos 10 años, se ha observado una disminución en la prevalencia de infección en todos los grupos etarios, en particular en población pediátrica y mayores de 60 años. La evolución de la infección depende de factores propios de la bacteria (virulencia, toxinas) y de la respuesta inmune del huésped. Los individuos infectados desarrollan principalmente patologías gastrointestinales como gastritis, úlcera péptica y linfoma MALT. La infección por H. pylori es el principal factor de riesgo del cáncer gástrico por lo que se recomienda su erradicación en caso de haberse detectado mediante test invasivo o no invasivo. En niños, no es recomendable la erradicación a menos que exista una manifestación clínica que lo amerite. Se recomienda su erradicación en adultos sintomáticos y existe controversia respecto a la erradicación masiva en población asintomática debido al riesgo de desarrollar resistencia antibiótica. El tratamiento se basa en el uso de inhibidores de la bomba de protones asociado a antibióticos, los cuales deben ser escogidos teniendo en cuenta la tasa de resistencia antimicrobiana y disponibilidad local. La resistencia a claritromicina (CLA) y levofloxacino es creciente, por lo que se recomienda el uso de esquemas de cuadriterapia libre de CLA en esquemas de primera línea. Se recomienda confirmar su erradicación con test no invasivos y retratar con esquema de segunda línea con antibióticos no utilizados previamente, asociado a dosis altas de inhibidores de bomba de protones y sales de bismuto.


Subject(s)
Humans , Child , Adult , Helicobacter Infections/drug therapy , Remission Induction , Helicobacter pylori/drug effects , Helicobacter pylori/pathogenicity , Helicobacter Infections/diagnosis , Helicobacter Infections/physiopathology , Age Factors , Clarithromycin/therapeutic use , Drug Resistance, Bacterial/drug effects , Drug Therapy, Combination , Proton Pump Inhibitors/therapeutic use , Levofloxacin/therapeutic use
10.
Vaccimonitor (La Habana, Print) ; 27(3)set.-dic. 2018. ilus, tab
Article in Spanish | LILACS, CUMED | ID: biblio-1094613

ABSTRACT

Helicobacter pylori es una bacteria gram negativa que posee numerosos antígenos que juegan un importante papel en la patogénesis de las enfermedades gastroduodenales. Debido a la necesidad de métodos de diagnóstico estandarizados con antígenos locales u autóctonos nos propusimos el diseño de una estrategia para la obtención de extractos de antígenos con reactividad frente a sueros de pacientes infectados por H. pylori. Dos cepas de H. pylori, una autóctona (IPK196A) y una de referencia ATCC 43504, se cultivaron en un medio líquido modificado. Se sometieron a los protocolos de ruptura por ultrasonido aplicándose tres variantes de precipitación y al fraccionamiento celular mediante ultracentrifugación diferencial. Los extractos proteínicos se visualizaron mediante electroforesis en gel de poliacrilamida y se transfirieron para la detección de antígenos inmunorreactivos a sueros de pacientes con infección por H. pylori e individuos sanos. La variante de ultrasonido y precipitación con Coomasie fue la más efectiva para concentrar las muestras. El método de ultracentrifugación mejoró la resolución de las proteínas reactivas y permitió separarlas según su localización subcelular. El sistema de transferencia húmedo fue ideal para la inmunodetección de los antígenos obtenidos por ultrasonido mientras que el sistema semiseco permitió detectar las proteínas de membrana obtenidas por ultracentrifugación diferencial. La introducción de una metodología en el laboratorio para la obtención y evaluación de extractos proteínicos antigénicos a partir de cepas autóctonas de H. pylori, constituye la antesala para el diseño de futuros diagnosticadores y candidatos vacunales(AU)


Helicobacter pylori is a gram-negative spiral-shaped bacterium, which has many antigens that play an important role in the pathogenesis of gastroduodenal diseases. Due to the lack of standardized methods from native or autochthonous antigens, we proposed in this study, the design of a strategy for extracting and obtaining immunoreactive antigens against H. pylori infected-patient sera. Two H. pylori strains, one autochthonous (IPK196A) and one reference ATCC 43504, were cultured in a modified liquid medium. Both strains were subjected to the ultrasound rupture protocols applying three precipitation variants and cell fractionation by differential ultracentrifugation. Protein extracts were visualized by polyacrylamide gel electrophoresis and transferred for the detection of immunoreactive antigens to sera from patients with H. pylori infection and healthy individuals. The precipitation with Coomasie was the most effective variant. The ultracentrifugation extraction method optimized the resolution of the proteins, which could be separated according to their subcellular location. The wet transfer system was ideal for the immunodetection of the antigens obtained by ultrasound, while the semi-dry system allowed detecting the membrane proteins by differential ultracentrifugation. The introduction of a methodology in the laboratory for obtaining and evaluating antigenic antibodies from autochthonous strains of H. pylori, is the prelude to the design for future diagnostics and vaccine candidates(AU)


Subject(s)
Humans , Male , Female , Ultracentrifugation/methods , Helicobacter pylori/pathogenicity , Electrophoresis, Polyacrylamide Gel/methods , Gastrointestinal Diseases/epidemiology
11.
Rev. argent. microbiol ; 50(4): 359-364, Dec. 2018. ilus, tab
Article in English | LILACS | ID: biblio-977257

ABSTRACT

Helicobacter pylori is a gastric pathogen that is widely recognized as a causative agent of gastric disease. Its eradication is variable, mainly due to increased resistance to clarithromycin. Our objective was: to evaluate (i) if the biopsy specimen used for the rapid urease test is a useful sample to detect resistance to clarithromycin by PCR-RFLP and (ii) the distribution of A2142G and A2143G point mutations in the 23S rRNA gene, in relation to virulence factors in our region. Gastric specimens were collected from adult dyspeptic patients (n = 141) and H. pylori was investigated by the rapid urease test, histopathological analysis and PCR for the hsp60 gene. Clarithromycin resistance was detected by PCR-RFLP in 62 H. pylori (+) paired biopsy specimens submitted to molecular analysis and the rapid urease test. H. pylori virulence factors were analyzed by multiplex PCR using specific primers for the cagA, vacA and babA2 genes. Thirteen out of 62 strains (20.9%) were resistant to clarithromycin: 6/13 (46.2%) harbored the A2143G mutation whereas 7/13 (53.8%) carried the A2142G point mutation. vacA m1s1 was the most frequent genotype among the resistant strains. In conclusion, the biopsy specimens used for the rapid urease test were suitable samples for clarithromycin resistance detection in patients infected with H. pylori, which became especially useful in cases where the number or size of the biopsies is limited. In addition, this is the first report of a molecular analysis for clarithromycin resistance performed directly from gastric biopsies in our region.


Helicobacter pylori es un patógeno ampliamente reconocido como causante de enfermedad gástrica. Su erradicación es variable, principalmente debido al incremento de la resistencia a claritromicina. Nuestros objetivos fueron evaluar la utilidad de la biopsia usada para realizar el test rápido de ureasa en la detección de resistencia a claritromicina por PCR-RFLP y conocer la distribución de las mutaciones puntuales A2142G y A2143G en el gen ARNr 23S, en relación con los factores de virulencia en nuestra región. Se recolectaron muestras gástricas (n=141) provenientes de pacientes adultos dispépticos y se investigó la presencia de H. pylori mediante el test rápido de ureasa, análisis histopatológico y PCR para el gen hsp60. La resistencia a claritromicina se analizó por PCR-RFLP en 62 muestras pareadas de biopsias gástricas H. pylori+ destinadas al análisis molecular y al test rápido de ureasa. Los factores de virulencia de H. pylori fueron analizados mediante PCR multiplex usando oligonucleótidos específicos para los genes cagA, vacA y babA2. Trece de 62 cepas (20,9%) fueron resistentes a claritromicina, 6/13 (46,2%) llevaron la mutación A2143G, mientras que 7/13 (53,8%) presentaron la mutación A2142G. El genotipo vacA s1m1 fue el más frecuente entre las cepas resistentes a claritromicina. En conclusión, las biopsias destinadas al test rápido de ureasa fueron muestras apropiadas para la detección de la resistencia a claritromicina en pacientes infectados con H. pylori. Esto es especialmente útil en aquellos casos en los que el número o el tamaño de las muestras son limitados. Además, este es el primer reporte de estudio de resistencia a claritromicina (mediante técnicas moleculares), directamente de biopsias gástricas en nuestra región.


Subject(s)
Humans , Helicobacter pylori/drug effects , Helicobacter Infections/diagnosis , Clarithromycin/pharmacology , Time Factors , Urease/metabolism , Polymorphism, Restriction Fragment Length , Microbial Sensitivity Tests , Polymerase Chain Reaction , Helicobacter pylori/enzymology , Helicobacter pylori/genetics , Helicobacter pylori/pathogenicity , Helicobacter Infections/microbiology , Point Mutation , Drug Resistance, Bacterial , Diagnostic Tests, Routine/methods
12.
Rev. cuba. pediatr ; 90(3): 1-10, jul.-set. 2018. ilus, tab
Article in Spanish | LILACS, CUMED | ID: biblio-978449

ABSTRACT

Introducción: la infección por Helicobacter pylori es muy común, particularmente en los países en vías de desarrollo, y juega un rol importante en la enfermedad ácido péptica. Objetivos: conocer la prevalencia y algunos datos clínico epidemiológicos, describir los hallazgos endoscópicos (gastritis eritematosa, nodular y úlcera duodenal), y relacionarlos con los hallazgos histológicos; describir la asociación entre los grados histológicos de la gastritis crónica y la positividad de la prueba de ureasa rápida y la presencia de Helicobacter pylori según histología, así como identificar la relación de los pacientes con gastritis crónica antral y úlcera duodenal por Hp, con la edad. Métodos: se realizó un estudio tipo descriptivo prospectivo durante 3 años se hizo una encuesta de síntomas a pacientes y/o padres y examen físico. Se realizó panendoscopia, previo consentimiento informado, y 2 biopsias de mucosa antral para prueba de ureasa rápida, así como estudio histopatológico (hematoxilina-eosina y Giemsa) para determinar el grado de gastritis y presencia de Helicobacter pylori según sistema Sydney. Se demostró la infección por uno de los métodos. Resultados: se seleccionaron 196 pacientes entre 7-18 años (media 14,6) de 471 (41,6 por ciento). El 53 por ciento era del sexo femenino, y el 59,7 por ciento tenía entre 10 y 14 años. Por endoscopia, el 49,5 por ciento tenía gastritis eritematosa antral, el 36,8 por ciento gastritis nodular astral, y el 13,7 por ciento úlcera duodenal con gastritis asociada. Con antecedentes familiares de úlcera péptica estuvo el 29,6 por ciento, con epigastralgia el 85,2 por ciento, con acidez el 46,4 por ciento con vómitos el 21 por ciento y con náuseas el 16,3 por ciento. En relación con el tiempo de evolución al diagnóstico, predominó el grupo de más de un año (24,5 por ciento), seguido del de 4-6 meses (22,4 por ciento). Todos presentaron gastritis crónica de diferentes grados: ligera (34,7 por ciento), moderada (37,2 por ciento) y severa (28,1 por ciento), con Helicobacter pylori por ureasa rápida 83,2 por ciento y 93,4 por ciento por histología, con coincidencia de ambos métodos en 150 (76,5 por ciento). Se observó presencia de nódulos linfoides en 41,8 por ciento. Conclusiones: la infección por Helicobacter pylori es frecuente en niños y adolescentes, causa lesiones inflamatorias gastroduodenales, en particular, gastritis nodular antral. Se encuentra una asociación importante del Helicobacter pylori por ambos métodos diagnósticos. Se recomienda seguimiento por biopsia, en especial, a los que continúan con infección crónica y presenten nódulos linfoides, por el riesgo de presentar linfoma gástrico de células B del tejido linfoide asociado a mucosa (linfoma MALT), si no se consigue la erradicación del Helicobacter pylori(AU)


Introduction: Helicobacter pylori infection is very common, particularly in developing countries, and plays an important role in acid peptic disease. Objectives: to know the prevalence and some clinical epidemiological data for describing the endoscopic findings (erythematous gastritis, nodular and duodenal ulcer), and to relate them with the histological findings; to describe the association among the histological degrees of chronic gastritis and the positivity of the rapid urease test, and the presence of Helicobacter pylori according to histology, as well as identifying by Hp with age the number of patients with chronic antral gastritis and duodenal ulcer. Methods: a prospective, descriptive study was carried out during 3 years, and a survey of symptoms was made to patients and / or parents and also physical examination. Panendoscopy was performed with prior informed consent, and also 2 antral mucosa biopsies for rapid urease test, as well as histopathological study (hematoxylin-eosin and Giemsa) to determine the degree of gastritis and the presence of Helicobacter pylori according to the Sydney system. Infection was demonstrated by one of the methods. Results: 196 patients among 7-18 years (mean 14.6) were selected of 471 (41.6 percent). 53 percent were female, and 59.7 percent were among 10 and 14 years old. By endoscopy, 49.5 percent had antral erythematous gastritis, 36.8 percent astral nodular gastritis, and 13.7 percent duodenal ulcer with associated gastritis. 29.6 percent had a family history of peptic ulcer, 85.2 percent of epigastralgia, 46.4 percent with acidity, 21 percent with vomiting, and 16.3 percent with nausea. In relation to the time of evolution to the diagnosis, the group of more than one year prevailed (24.5 percent followed by the one of 4-6 months (22.4 percent). All presented chronic gastritis of different degrees: light (34.7 percent), moderate (37.2 percent) and severe (28.1 percent), with Helicobacter pylori by rapid urease 83.2 percent, and 93.4 percent by histology with coincidence of both methods in 150 (76.5 percent). The presence of lymphoid nodules was observed in 41.8 percent. Conclusions: Helicobacter pylori infection is frequent in children and adolescents causing gastroduodenal inflammatory lesions, in particular antral nodular gastritis. An important association of Helicobacter pylori is found by both diagnostic methods. Follow-up by biopsy is recommended, especially those who continue with chronic infection and have lymphoid nodules due to the risk of presenting B-cell gastric lymphoma of the lymphoid tissue associated to the mucosa (MALT lymphoma), if Helicobacter pylori eradication is not achieved(AU)


Subject(s)
Humans , Male , Female , Child , Adolescent , Helicobacter Infections/epidemiology , Helicobacter Infections/diagnostic imaging , Gastritis/complications , Epidemiology, Descriptive , Prospective Studies , Helicobacter pylori/pathogenicity
14.
Middle East Journal of Digestive Diseases. 2018; 10 (1): 24-30
in English | IMEMR | ID: emr-192421

ABSTRACT

Background: Cholecystitis is a common surgical condition. Recently, several authors have reported that DNA of bile tolerant Helicobacter spp. has been found in the human bile colonizing the biliary tract. The aim of this study was to evaluate the association between the presence of Helicobacter spp. and gallstone cholecystitis


Methods: In this case-control study, gallstones, bile, and gallbladder mucosa were collected from 25 patients without gallstone disease, 24 with acute cholecystitis, and 28 with chronic cholecystitis. The presence of Helicobacter pylori [H. pylori], Helicobacter bilis [H. bilis], Helicobacter hepaticus [H. hepaticus], and Helicobacter pullorum [H. pullorum] were investigated by polymerase chain reaction [PCR] using species-specific primers


Results: In this study, 77 subjects with acute and chronic cholecystitis and control groups with a mean age of 46.85 +/- 14.53 years, including 58 [67.25%] women and 19 [32.75%] men were included. DNA of 10 Helicobacter spp. was detected in the bile of the patients with cholecystitis including eight H. pylori and two H. bilis. However, we could not detect H. hepaticus and H. pullorum DNA in the samples. Moreover, there was an association between H. pylori and acute cholecystitis [p = 0.048], which was found to be stronger in 31-40-year-olds group [p = 0.003]


Conclusion: We found an association between the presence of H. pylori DNA and acute gallstone cholecystitis. There is not statistically significant correlation between three enterohepatic Helicobacter spp. [H. bilis, H. hepaticus, and H. pullorum] and cholelithiasis. Given the low sample size of the patients, more studies are required to clear the clinical role of Helicobacter spp. in the gallstone disease and cholecystitis


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Gallstones , Cholecystitis/microbiology , Helicobacter pylori/pathogenicity , Case-Control Studies
15.
Gastroenterol. latinoam ; 29(supl.1): S13-S20, 2018. ilus, graf
Article in Spanish | LILACS | ID: biblio-1117577

ABSTRACT

H. pylori infection is a fascinating history, which combines the roles as one of the most prevalent commensal and a a pathogen responsible for severe diseases, some of them unimaginable until the end of last century, such as gastric cancer. In this review we present the available evidence that might help to identify the main mode of transmission of H. pylori and we discuss which could be the potential approaches to prevent the transmission of this bacterium in countries with high and low prevalence.


La infección por Helicobacter pylori es una historia fascinante, en donde se combinan el papel de un comensal con el de un patógeno humano que produce enfermedades graves, algunas inimaginables hasta hace menos de 30 años, como es el caso de cáncer gástrico. En esta revisión discutimos las evidencias disponibles en función de la prevalencia e incidencia de H. pylori tanto en países económicamente desarrollados como en proceso de desarrollo y tratamos de establecer cuál es el principal modo de transmisión de este organismo. Finalmente, se discuten cuáles pueden ser las mejores medidas de prevención, tanto en países con baja prevalencia como en aquellos con una alta prevalencia.


Subject(s)
Humans , Helicobacter Infections/prevention & control , Helicobacter Infections/transmission , Global Health , Incidence , Helicobacter pylori/pathogenicity , Helicobacter Infections/epidemiology
16.
Arq. gastroenterol ; 54(3): 217-221, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-888207

ABSTRACT

ABSTRACT BACKGROUND: The clinical outcome of Helicobacter pylori infection has been associated with virulence factors. The presence of these factors is useful as molecular markers in the identification of the high risk for developing severe gastric pathologies. OBJECTIVE: To correlate the presence of virulence markers cagA and bab2A of H. pylori in oral and gastric biopsy samples. METHODS: An observational, prospective, descriptive, and cross-sectional study was carried out between September 2011 and September 2012. Patients suffering dyspepsia with indication for upper gastrointestinal video endoscopy who attended the Gastroenterology Service of the Hospital Dr. Julio C. Perrando were included. Epidemiological investigation was completed. To detect the bacteria and their virulence genes, samples of saliva, dental plaque and gastric biopsy were taken and processed by PCR. RESULTS: Sixty-one patients were selected for this study (30 women and 31 men). H. pylori was detected in 31 gastric biopsies and 31 oral samples. Significant difference between oral and gastric samples was found in cagA genotype. Agreement between oral and gastric genotypes was found in 38.7% of samples from the same patient. CONCLUSION: This study is the first in provide information about the genotypes of the Argentinean Northeast H. pylori strains. Despite the high prevalence of H. pylori infection, the most of patients had less virulent genotypes in oral cavity and gastric tissue. The cagA / babA2 combination was not frequent in the samples studied. There was not a statistical correlation between the virulence genes and gastroduodenal or oral diseases. Although in some patients the same genotype was found both in oral and gastric samples, it cannot be ensure that they corresponding to the same strain because a DNA sequencing was not performed.


RESUMO CONTEXTO: O resultado clínico da infecção por Helicobacter pylori tem sido associado com fatores de virulência. A presença desses fatores como marcadores moleculares é útil na identificação do risco elevado para o desenvolvimento de graves patologias gástricas. OBJETIVOS: Correlacionar a presença de marcadores de virulência cagA e bab2A do H. pylori em amostras de biópsias gástricas e orais. MÉTODOS: Um estudo observacional, prospectivo, descritivo e transversal foi realizado entre setembro de 2011 e setembro de 2012. Foram incluídos pacientes com sintomas de dispepsia com indicação de endoscopia gastrointestinal que compareceram ao Serviço de Gastroenterologia do Hospital Dr. Julio C. Perrando . Investigação epidemiológica foi concluída. Para detectar a bactéria e seus genes de virulência, amostras de saliva, placa dentária e biópsia gástrica foram tomadas e processadas pelo PCR. RESULTADOS: Sessenta e um pacientes foram selecionados para este estudo (30 mulheres e 31 homens). H. pylori foi detectado em 31 biópsias gástricas e 31 amostras orais. Foi encontrada diferença significativa entre as amostras orais e gástricas no genótipo cagA . A ocorrência simultânea entre genótipos orais e gástricos do mesmo paciente foi encontrada em 38,7% das amostras. CONCLUSÃO: Este é o primeiro estudo a fornecer informações sobre os genótipos das cepas do H. pylori no Nordeste Argentino. Apesar da alta prevalência da infecção pelo H. pylori , a maioria dos pacientes tinha genótipos menos virulentos na cavidade oral e tecido gástrico. A combinação cagA / babA2 não foi frequente nas amostras estudadas. Não houve correlação estatística entre os genes de virulência e doenças gastroduodenais ou orais. Embora em alguns pacientes o mesmo genótipo tenha sido encontrado tanto nas amostras orais quanto gástricas, não se pode garantir que correspondam à mesma variação, pois um sequenciamento de DNA não foi realizado.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Bacterial Proteins/genetics , Helicobacter pylori/pathogenicity , Helicobacter Infections/microbiology , Adhesins, Bacterial/genetics , Gastric Mucosa/microbiology , Mouth/microbiology , Antigens, Bacterial/genetics , Biopsy , Biomarkers/analysis , Cross-Sectional Studies , Prospective Studies , Helicobacter pylori/isolation & purification , Virulence Factors/genetics , Genotype , Middle Aged
17.
Rev. medica electron ; 39(3): 507-518, may.-jun. 2017.
Article in Spanish | LILACS, CUMED | ID: biblio-902190

ABSTRACT

Introducción: el cáncer gástrico avanzado constituye la segunda causa de muerte por tumores malignos en el mundo. En los últimos cinco años en la provincia de Matanzas existe un incremento de esta patología. Objetivo: determinar el comportamiento clínico epidemiológico del cáncer gástrico avanzado diagnosticado por videoendoscopía, en el departamento de Gastroenterología del Hospital Universitario "Comandante Faustino Pérez Hernández", de Matanzas en el período de enero del 2014 a enero del 2016. Materiales y Métodos: se realizó un estudio observacional, descriptivo y prospectivo en el Departamento de Gastroenterología del Hospital Universitario "Comandante Faustino Pérez Hernández", de Matanzas en el período de enero del 2014 a enero del 2016. El universo los 28 pacientes que presentaron cáncer gástrico avanzado por diagnóstico endoscópico e histológico. Resultados: el grupo de edad más afectado correspondió a los pacientes con 60 años de edad o más (67,9 %). El sexo masculino predominó, un 57,1 %. Los factores de riesgo de mayor incidencia fueron la dieta inadecuada (65 %) y el hábito de fumar (42,9 %). Las manifestaciones clínicas más relevantes fueron la pérdida de peso, la astenia y la acidez. La variedad histica que predominó fue el adenocarcinoma de tipo intestinal y el antro gástrico resultó ser la localización más frecuente. La mayoría de los pacientes tuvieron positivos el test de ureasa para la infección por Helicobacter pylori. (60,7 %). Conclusiones: la infección por Helicobacter pylori constituye una de las principales causas de cáncer gástrico. El diagnóstico y tratamiento precoz de la infección contribuirán a disminuir su incidencia (AU).


Introduction: the advanced gastric cancer is the second reason of death due to malignant cancer in the world. There it is a surge of this disease in the last five years in the province of Matanzas. Objective: to determine the clinical-epidemiologic behavior of advanced gastric cancer diagnosed by video-endoscopy in the Department of Gastroenterology of the Teaching Hospital "Comandante Faustino Pérez Hernández", of Matanzas, in the period from January 2014 to January 2016. Materials and Methods: an observational, descriptive and prospective study of the department of Gastroenterology of the Teaching Hospital "Comandante Faustino Pérez Hernández", of Matanzas, was carried in the period from January 2014 to January 2016. The universe were 28 patients who had advanced gastric cancer according to the endoscopic and histological diagnosis. Outcomes: the most affected age group was the one of the patients aged 60 years and more (67,9 %).The male sex predominated, with 57,1 %. The risk factors with higher incidence were an inadequate diet (65 %) and smoking (42,9 %). The most relevant clinical manifestations were weight loss, asthenia and heartburn. The predominating histological variety was the intestinal type adenocarcinoma and the gastric antrum was the most frequent location. Most of the patients were positive to the urease test for helicobacter pylori (60,7 %). Conclusions: the infection by Helicobacter pylori is one of the main causes of gastric cancer. The precocious diagnosis and treatment of the infection will favor the reduction of its incidence (AU).


Subject(s)
Humans , Male , Female , Stomach Neoplasms/diagnostic imaging , Capsule Endoscopy/methods , Stomach Neoplasms/diagnosis , Stomach Neoplasms/epidemiology , Helicobacter pylori/pathogenicity , Observational Studies as Topic , Neoplasms/complications , Neoplasms/diagnosis , Neoplasms/epidemiology
18.
Rev. méd. panacea ; 6(1): 28-35, ene.-abr. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-1022634

ABSTRACT

Objetivo: Determinar la relación entre Helicobacter pylori y patologías digestivas altas mediante biopsia dirigida por endoscopia en el Hospital Regional de Ica, diciembre 2016 y enero 2017. Material y métodos: Se realizó un estudio observacional descriptivo transversal, cuya muestra estuvo conformada por 228 pacientes escogidos de forma aleatoria, que acudieron a consultorio de procedimientos endoscópicos gastrointestinales del Hospital Regional de Ica durante diciembre del 2016 y enero del 2017. Para determinar la relación entre Helicobacter pylori y patologías digestivas altas, creamos un instrumento de recolección de datos, se realizó el análisis exploratorio, univariado y bivariado (OR, Chi² y ANOVA), en la base de datos SPSS 22. Resultados: La relación entre presencia de Helicobacter pylori y Gastritis crónica (p=0.00) fue significativa, no se encontró relación con otra patología. El proceder de lugares diferentes de Ica se encontró asociado a infección por Helicobacter pylori, siendo un factor protector (OR: 0.25, p=0.04), el ingerir verduras y frutas tienen asociación significativa con la infección, comportándose como factores protectores (p<0.05), y el consumo de carnes y tubérculos incrementan la probabilidad de infectarse con el microorganismo (ORc: 2.63 y ORt: 2.29, p<0.05). Conclusiones: Existe relación entre Gastritis crónica e infección por Helicobacter pylori, consumir verduras y frutas disminuye la probabilidad de infección, mientras que consumir abundantes carnes y tubérculos incrementan el riesgo de infección; y residir fuera de Ica es un factor que disminuye la probabilidad de infectarse. (AU)


Objetive: To determine the relationship between the presence of Helicobacter pylori and upper digestive pathologies by endoscopy-guided biopsy at the Regional Hospital of Ica, December 2016 and January 2017. Materials and Methods: A cross-sectional, observational, descriptive study was performed. 228 randomly selected patients who visited the gastrointestinal endoscopic procedures of the Regional Hospital of Ica during the months of December 2016 and January 2017. To determine the relationship between the presence of Helicobacter pylori and upper digestive pathologies, we created an instrument (OR, Chi² and ANOVA) were analyzed in the SPSS 22 database. Results: The relationship between the presence of Helicobacter pylori and chronic gastritis (p = 0.00) is significant, No relationship was found with other pathology. The procedure of different sites of Ica is associated with Helicobacter infection, being a protective factor (OR: 0.25, p = 0.04), ingesting vegetables and fruits have a significant association with infection, behaving as protective factors (p <0.05), And the consumption of meats and tubers increases the probability of being infected with the microorganism (ORc: 2.63 and ORt: 2.29, p <0.05).Conclusions: There is a relationship between chronic Gastritis and Helicobacter pylori infection, consuming vegetables and fruits reduces the probability of infection, while consuming abundant meats and tubers increase the risk of infection; And residing outside of Ica is a factor that decreases the probability of becoming infected. (AU)


Subject(s)
Humans , Male , Female , Stomach Neoplasms/pathology , Biopsy , Helicobacter pylori/pathogenicity , Endoscopy , Gastritis/pathology , Epidemiology, Descriptive , Cross-Sectional Studies , Observational Study
19.
Clinics ; 72(3): 150-153, Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-840051

ABSTRACT

OBJECTIVE: Esophageal squamous cell carcinoma is one of the most common esophageal diseases in the developing world, but the relationship between esophageal squamous cell carcinoma and Helicobacter pylori infection remains a neglected topic. The primary objective of this study was to determine the association between Helicobacter pylori infection and esophageal squamous cell carcinoma. A second purpose was to determine the incidence and factors associated with Helicobacter pylori infection following esophagectomy. METHOD: The microorganism was identified by testing the gastric biopsy materials from 95 esophageal squamous cell carcinoma patients (66 females; 39 were esophagectomized) for urease activity in a medium containing urea and a power of hydrogen detection reagent and comparing the results with those from a healthy population. Differences in patient characteristics were assessed with chi-square tests and t-tests for categorical and continuous factors, respectively. RESULTS: The patients with esophageal squamous cell carcinoma had a significantly lower prevalence of Helicobacter pylori compared with the healthy population (p<0.001). The naive and esophagectomized patients, in contrast, showed no significant differences in Helicobacter pylori infection (p>0.005). Patients with esophageal squamous cell carcinoma showed a significant association between leukocytosis and hypoglobulinemia and the presence of Helicobacter pylori infection (p=0.023 and p=0.045, respectively). CONCLUSION: These results suggest that Helicobacter pylori is not an etiological factor in patients with esophageal squamous cell carcinoma. We found a statistically significant negative correlation between esophageal squamous cell cancer and Helicobacter pylori infection. These findings may guide new strategies for esophageal squamous cell carcinoma therapy.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/microbiology , Esophageal Neoplasms/microbiology , Helicobacter Infections/complications , Helicobacter pylori/isolation & purification , Biopsy , Carcinoma, Squamous Cell/pathology , Case-Control Studies , Esophageal Neoplasms/pathology , Helicobacter Infections/pathology , Helicobacter pylori/pathogenicity , Retrospective Studies , Risk Factors , Sex Factors , Statistics, Nonparametric
20.
Rev. cuba. med. mil ; 45(4): 1-9, set.-dic. 2016. tab
Article in Spanish | LILACS, CUMED | ID: biblio-960566

ABSTRACT

Introducción: existen evidencias de la participación de ciertos genotipos del Helicobacter pylori con patologías más severas. Objetivo: determinar la frecuencia del gen cagA y las variantes alélicas de la citotoxina vacA del Helicobacter pylori en un grupo de pacientes dispépticos, así como el daño causado en la mucosa gástrica por esta bacteria. Métodos: se realizó un estudio descriptivo en el Hospital Dr. Carlos J. Finlay, desde el 2011-2012. La muestra estuvo conformada por 71 pacientes con cultivo positivo para Helicobacter, a los que se les realizó endoscopía con toma de biopsias. Se realizó determinación del gen cagA y de los alelos de la citotoxina vacA y se determinó mediante estudio histológico el daño causado en la mucosa gástrica por la bacteria. Se utilizó el método estadístico Chi cuadrado con una significación estadística de alfa < 0,05 para determinar la significación de los genotipos. Resultados: el 69 por ciento de los pacientes fue cagA+ y el 56,3 por ciento vacA s1m1. En los individuos cagA+ predominaron los alelos s1m1 (52,1 por ciento) y en los cagA- las variantes s2m2 (22,5 por ciento). La gastritis crónica moderada fue el diagnóstico histológico más frecuente relacionado con el genotipo cagAvacAs1m1. Conclusiones: los pacientes dispépticos estudiados presentaron con mayor frecuencia una cepa muy virulenta (cagA+/vacAs1m1), aunque el daño histológico sobre la mucosa gástrica fue menor del esperado(AU)


Introduction: There is evidence of the involvement of certain genotypes del Helicobacter pylori in more several pathologies. Objective: Determine the frequency of gen cagA and the citotoxinavacA of Helicobacter pylori in dyspeptic patients and the damage of gastric mucosa. Methods: A descriptive study was conducted at the Hospital Dr. Carlos J. Finlay, from 2011-2012 in 71 patients with positive culture for Helicobacter . The study included determination of the gen cagA and the citotoxinavacA. The analysis of results was performed using the Chi square statistic method with statistical significance alpha <0.05. Results: 69 percent of patients wascagA+ and 56.3 percent vacAs1m1. In individuals cagA+ predominateds1m1 (52.1 percent) and in the cagA- predominate s2m2 (22.5 percent). The moderate chronic gastritis was the most frequent histological diagnosis related to the cagAvacAs1m1 genotype. Conclusions: A highly virulent strain (cagA + / vacAs1m1) predominate in dyspeptic patients of this study(AU)


Subject(s)
Humans , Adolescent , Adult , Middle Aged , Aged , Biopsy/methods , Helicobacter pylori/pathogenicity , Gastritis, Atrophic/diagnosis , Epidemiology, Descriptive
SELECTION OF CITATIONS
SEARCH DETAIL