Avaliação da expressão das moléculas HLA de classe I não clássicas HLA-G E HLA-E em espécimes gástricas de pacientes acometidos com a bactéria Helicobacter Pylori

The expression of human leukocyte antigen G (HLA-G) and human leukocyte antigen E (HLA-E) in physiological and pathological processes remains unknown, it is believed that these molecules play a fundamental role in the establishment and maintenance of immune tolerance by inhibiting the functions of immunocompetent cells. In literature we found no published study involving the bacterium Helicobacter pylori (H. pylori) with expression of HLA-G and HLA-E. The objective this study is investigated the expression of this protein in gastric biopsies of patients with the bacterium H. pylori. Sixty-four biopsies of the patients with diagnosis of infection by H. pylori were evaluated to expression of HLA-G and HLA-E. The samples were stratified according to the presence of carcinoma or peptic ulcers. Patients without H. pylori were used to control. To investigate the expression of this protein were used immunohistochemistry technique with monoclonal antibody anti-HLA-G and anti-HLA-E. Other criteria such as analysis of the inflammatory infiltrate (hematoxylin-eosin) and identification of H. pylori (Giemsa) were analyzed. We detected HLA-G and HLA-E molecules in the most samples containing ulcer and gastric carcinoma. In negative control group was not detected the presence of HLA-G and HLA-E. The presence of H. pylori seems modulate the expression of HLA-G and HLA-E, favoring the evolution of infection, giving different degrees of gastric lesion in epithelium of these patients

Antígenos de Helicobacter pylori en muestras fecales de usuarios con sintomatología sugestiva a gastritis que asisten a la Unidad Comunitaria de Salud Familiar Especializada de Perquin, departamento de Morazán

En la actualidad se reconoce a Helicobacter pylori como un agente patógeno involucrado en el desarrollo de gastritis crónica, úlcera gástrica y carcinoma gástrico. Lo que hace necesario realizar pruebas para detectar la presencia de la bacteria a través de diferentes métodos de laboratorio EL OBJETIVO de la investigación fué Determinar antígenos de Helicobacter pylori en muestras fecales de usuarios con sintomatología sugestiva a gastritis que asisten a la Unidad Comunitaria de Salud Familiar Especializada de Perquín, Departamento de Morazán. METODOLOGÍA de la investigación se caracterizó por ser: Prospectiva, Transversal, Descriptiva y de Laboratorio. Con una población en estudio de 97 usuarios a los cuales se les aplicó una cédula de entrevista para la recopilación de la información. A través de una muestra de heces se determinó la presencia de antígenos de Helicobacter pylori. RESULTADOS: según datos obtenidos, se determinó una positividad a la prueba de antígenos de Helicobacter pylori de 52.4% en la población femenina entre las edades de 15 a 75 años y un 38.2% en la población masculina entre las edades de 15 a 75 años. El síntoma que mayormente se presentó en la población que resultó positiva a la prueba fue dolor en la parte superior del estómago con un 87%. CONCLUSIÓN: Mediante resultados de laboratorio la presencia de antígenos de Helicobacter pylori en heces fue de 47.4% del total de la población. Comprobándose estadísticamente que la presencia de antígenos de Helicobacter pylori en las muestras fecales de usuarios con sintomatología sugestiva a gastritis es menor o igual al 40%.

Detección de antígenos de Helicobacter pylori por el método de prueba rápida en estudiantes de Bachillerato Técnico Vocacional Atención Primaria en Salud del Instituto Nacional de Usulután, municipio y departamento de Usulután

Helicobacter pylori es una bacteria gram negativa capaz de sobrevivir a la acidez gástrica provocando gastritis crónica, úlcera péptica y cáncer gástrico; las técnicas empleadas para la detección de esta bacteria se dividen en invasivas y no invasivas que brindan un diagnóstico confiable a la población en estudio. OBJETIVO: Detectar la presencia de antígenos de Helicobacter pylori por el método de prueba rápida inmunocromatográfica en heces en los estudiantes de Bachillerato Técnico Vocacional Atención Primaria en Salud del Instituto Nacional de Usulután. METODOLOGÍA: El estudio fue: prospectivo, transversal, descriptivo y de laboratorio; la información de la población en estudio se dio a conocer por medio de una cédula de entrevista; la población en estudio estuvo conformada por 167 alumnos que cursan Bachillerato Técnico Vocacional Atención Primaria en Salud del Instituto Nacional de Usulután tanto en jóvenes que presentaron sintomatología como los que no la presentaron, se le tomó una muestra de heces para la detección de antígenos de Helicobacter pylori. RESULTADO: 66 estudiantes de Bachillerato Técnico Vocacional Atención Primaria en Salud del Instituto Nacional de Usulután presentaron pruebas positivas a antígenos de Helicobacter pylori en muestras fecales y 101 resultaron negativos a la prueba. CONCLUSIÓN: la positividad a antígenos de Helicobacter pylory 39.5%, el síntoma más frecuente en los estudiantes fue reflujo gástrico con 63.2%.

Antígenos de Helicobacter pylori en muestras fecales de personas con sintomatología de reflujo gástrico que consultan en la Unidad Comunitaria de Salud Familiar Moncagua, departamento de San Miguel y Hospital Nacional San Pedro, departamento de Usulután

La bacteria Helicobacter pylori es reconocida como el principal agente causal de la gastritis crónica activa, úlcera péptica, reflujo gástrico así como un factor de predisposición del carcinoma gástrico. La detección oportuna de ésta favorece un tratamiento adecuado y evita posibles complicaciones. El Objetivo de la investigación es determinar antígenos de Helicobacter pylori en muestras fecales de personas con sintomatología de reflujo gástrico que consultan en la Unidad Comunitaria de Salud Familiar Moncagua, Departamento de San Miguel y Hospital Nacional San Pedro, Departamento de Usulután. Metodología: El estudio es de tipo prospectivo, transversal, descriptivo y de laboratorio. La población fue de 150 personas y la muestra fue de 133 personas para el Hospital Nacional San Pedro y 17 personas para la Unidad de Salud Moncagua, se realizó prueba cualitativa de antígenos de Helicobacter pylori en muestras fecales, además se administró a las personas una cédula de entrevista con la que se obtuvo información relacionada con el tema. Resultados: De 103 con reflujo gástrico en el Hospital San Pedro de Usulután 50 personas (48.5%) dieron positivos a la prueba de antígenos de Helicobacter pylori en muestras fecales y de 13 personas con este síntoma en la Unidad de Salud Moncagua de San Miguel 2 personas (15.4%) dieron positivos a la prueba. Conclusiones: El 44.8% de las personas que presentan reflujo gástrico resultaron con prueba positiva a antígenos de Helicobacter pylori en muestras fecales, por lo que se recomienda que toda persona que presenta síntoma de reflujo gástrico se realice la prueba de antígenos de Helicobacter pylori para descartar una posible infección por esta bacteria.

Soroepidemiologia da Helicobacter pylori em crianças e suas mães: avaliação dos fatores de risco

Uma investigação com o objetivo de estudar a soroprevalência da infecção pela bactéria Helicobacter pylori foi realizada em 100 crianças, entre 1 e 12 anos, no Hospital Universitário João de Barros Barreto, em Belém, Brasil, e em suas respectivas 100 mães. Analisaram-se possíveis fatores de risco relacionados à infecção e possíveis associações da infecção entre as mães e seus filhos, inclusive por cepas CagA. Colheram-se amostras de sangue e saliva de todos os participantes e fezes das crianças. A sorologia anti-H. pylori foi realizada pela hemaglutinação indireta e a anti-CagA por Elisa. Os fenótipos ABH e Lewis no sangue foram determinados por hemaglutinação direta e na saliva por dot-blot Elisa. Pesquisou-se antígenos da bactéria em 79 amostras de fezes das crianças por um Elisa de captura. Informações pessoais e familiares foram obtidas através de um questionário padrão. A soroprevalência nas crianças foi de 50,0% e nas mães de 86,0%. A soroprevalência nas crianças aumentou com a idade (p<0,05) e com o hábito de freqüentarem creche ou escola (p<0,05). Os métodos Elisa de captura e hemaglutinação indireta apresentaram desempenhos semelhantes nas crianças, sendo que nas de 1 a 4 anos observaram-se maiores discordâncias (p<0,05). Mães infectadas representaram fator de risco para infecção em seus filhos (p<0,05), sobretudo mães com cepas CagA (p<0,005). Procedência de municípios com 100 mil habitantes ou mais (p<0,05), água encanada (p<0,05), ausência de instalações sanitárias (p<0,005) e de saneamento na residência (p<0,05) representaram risco para infecção familiar. A transmissão da H. pylori foi facilitada pelas precárias condições de higiene e saneamento, conglomerados urbanos e por contatos íntimos entre as crianças e mães, mediante as rotas de transmissão fecal-oral, oral-oral e/ou gastro-oral.

Prevalencia del Helicobacter Pylori y factores asociados en escolares de la etnia Shuar del cantón Sucúa –Morona Santiago, 2014.

Introducción: Según la OMS, más del 50% de la población adulta está infectada con el Helicobacter Pylori, con prevalencias de hasta el 90%. La mayoría de contagios se produce antes de los 10 años de edad. Desde el descubrimiento del H. Pylori (1983), se lo ha relacionado con la úlcera péptica, gastritis, reflujo gastroesofágico e incluso, cáncer gástrico. Metodología: Se realizó un estudio transversal analítico. La muestra estuvo conformada por 250 niños escolares de la etnia Shuar del cantón Sucúa. La prueba utilizada para la detección del Helicobacter pylori es la identificación de antígenos en las heces por inmunocromatografía. Para establecer la significancia de asociación de variables se utilizó el OR con su intervalo de confianza al 95%. Resultados: El promedio de edad fue de 8.8 años (DS 2.0), con predominio de las mujeres (54.4%). El 56.4% consume agua potable, el 71.65% vive en hacinamiento, el 42% tiene servicios de letrinización y el 49.2% cuenta con servicios de alcantarillado. Se encontró asociación significativa con el nivel de instrucción OR 1.68, IC95% (1 – 2.84), p=0.049; letrinización OR 1.99, IC95% (1.17 – 3.36), p=0.01; deposiciones al aire libre OR 4.32, IC95% (2.13 – 8.77), p=0.000. Conclusiones: La prevalencia de Helicobacter pylori es alta en la población escolar de la etnia Shuar; está asociada a un nivel bajo de instrucción de los progenitores y una inadecuada infraestructura de servicios básicos.

Current treatment of Helicobacter pylori infection and peptic ulcer disease

Since the initial report by Warren and Marshall in 1984, Helicobacter pylori has assumed an increasingly important role in the pathogenesis of peptic ulcer disease and gastric carcinoma in all ages. A recent National Institutes of Health Consensus Development conference acknowledges the relationship between H. pylori infection and peptic ulcer disease and recommends that the medical community treat H. pylori infection in all patients with Helicobacter pylori and peptic ulcer. Although the same organism, the response to Helicobacter pylori infection in childhood differs somewhat from that seen in adults. The paediatric patient mounts a different inflammatory response, has different macroscopic appearances and has a markedly diminished peptic ulcer disease frequency compared with their adult counterparts. The appearances of antral nodularity appear to be characteristic of Helicobacter pylori infections. The appearances, however, are unrelated to symptoms and the underlying cause for this nodularity remains obscure. Younger children with peptic ulcer diseases are more likely to be Helicobacter pylori negative. This may suggest an increased susceptibility to gastric acid or possibly a very transient Helicobacter pylori infection rather than the well described lifelong infection without treatment. It is well known that the epidemiology of Helicobacter pylori would suggest that the incidence of infection increases with age. There is also geographical variations with the incidence being higher in countries of a third world background. These epidemiological observations fly in the face of all other infections where the major period of acquisition is in childhood. There has been recent evidence to suggest that in fact the incidence in childhood is decreasing in developed countries which could support the observation that there is a decreasing positive serology with successive decades in some countries. It is felt that the most likely mode of transmission of Helicobacter pylori is faecal to oral or oral to oral route. These are similar modes of transmission to Hepatitis A infections. It is obvious that most infections in childhood remain asymptomatic. It is also clear that there is no relationship between chronic recurrent abdominal pain of childhood syndrome and the presence of Helicobacter pylori infections. It remains to be seen as to who should be treated, what with and when. All of these issues will be discussed in the paper.

Helicobacter pylori: resistance and treatment results in Finland

Background: Helicobacter pylori infection is usually acquired in early childhood and is rarely resolved spontaneously. Eradication therapy is currently recommended virtually to all patients. While the first and second therapies are prescribed without knowing the antibiotic resistance of the bacteria, it is important to know the primary resistance in the population. Aim: This study evaluates the primary resistance of H. pylori among patients in primary health care throughout Finland, the efficacy of three eradication regimens, the symptomatic response to successful therapy, and the effect of smoking on gastric histology and humoral response in H. pylori-positive patients. Patients and methods: A total of 23 endoscopy referral centres located throughout Finland recruited 342 adult patients with positive rapid urease test results, who were referred to upper gastrointestinal endoscopy from primary health care. Gastric histology, H. pylori resistance and H. pylori serology were evaluated. The patients were randomized to receive a seven-day regimen, comprising 1) lansoprazole 30 mg b.d., amoxicillin 1 g b.d. and metronidazole 400 mg t.d. (LAM), 2) lansoprazole 30 mg b.d., amoxicillin 1 g b.d. and clarithromycin 500 mg b.d. (LAC) or 3) ranitidine bismuth citrate 400 mg b.d., metronidazole 400 mg t.d. and tetracycline 500 mg q.d. (RMT). The eradication results were assessed, using the 13C-urea breath test 4 weeks after therapy. The patients completed a symptom questionnaire before and a year after the therapy. Results: Primary resistance of H. pylori to metronidazole was 48% among women and 25% among men. In women, metronidazole resistance correlated with previous use of antibiotics for gynaecologic infections and alcohol consumption. Resistance rate to clarithromycin was only 2%. Intention-to-treat cure rates of LAM, LAC, and RMT were 78%, 91% and 81%. While in metronidazole-sensitive cases the cure rates with LAM, LAC and RMT were similar, in metronidazole resistance LAM and RMT were inferior to LAC (53%, 67% and 84%). Previous antibiotic therapies reduced the efficacy of LAC, to the level of RMT. Dyspeptic symptoms in the Gastrointestinal Symptoms Rating Scale (GSRS) were decreased by 30.5%. In logistic regression analysis, duodenal ulcer, gastric antral neutrophilic inflammation and age from 50 to 59 years independently predicted greater decrease in dyspeptic symptoms. In the gastric body, smokers had milder inflammation and less atrophy and in the antrum denser H. pylori load. Smokers also had lower IgG antibody titres against H. pylori and a smaller proportional decrease in antibodies after successful eradication. Smoking tripled the risk of duodenal ulcers. Conclusions: in Finland H. pylori resistance to clarithromycin is low, but metronidazole resistance among women is high making metronidazole-based therapies unfavourable. Thus, LAC is the best choice for first-line eradication therapy. The effect of eradication on dyspeptic symptoms was only modest. Smoking slows the progression of atrophy in the gastric body.

Characterization of an N6 adenine methyltransferase from Helicobacter pylori strain 26695 which methylates adjacent adenines on the same strand

Genomic sequences of Helicobacter pylori strains 26695, J99, HPAGI and G27 have revealed an abundance of restriction and modification genes. hp0050, which encodes an N6 adenine DNA methyltransferase, was cloned, overexpressed and purified to near homogeneity. It recognizes the sequence 5'-GRRG-3' (where R is A or G) and, most intriguingly, methylates both adenines when R is A (5'-GAAG-3'). Kinetic analysis suggests a nonprocessive (repeated-hit) mechanism of methylation in which HP0050 methyltransferase methylates one adenine at a time in the sequence 5'-GAAG-3'. This is the first report of an N6 adenine DNA methyltransferase that methylates two adjacent residues on the same strand. Interestingly, HP0050 homologs from two clinical strains of H. pylori (PG227 and 128) methylate only 5'-GAGG-3' compared with 5'-GRRG-3' in strain 26695. HP0050 methyltransferase is highly conserved as it is present in more than 90% of H. pylori strains. Inactivation of hp0050 in strain PG227 resulted in poor growth, suggesting its role in the biology of H. pylori. Collectively, these findings provide impetus for exploring the role(s) of this conserved DNA methyltransferase in the cellular processes of H. pylori.

A prospective randomised trial of a "test and treat" policy versus endoscopy based management in young Helicobacter pylori positive patients with ulcer-like dyspepsia, referred to a hospital clinic

Management of dyspepsia remains a controversial area. Although the European Helicobacter pylori study group has advised empirical eradication therapy without oesophagogastroduodenoscopy (OGD) in young H pylori positive dyspeptic patients who do not exhibit alarm symptoms, this strategy has not been subjected to clinical trial.

Rapid serological diagnosis of Helicobacter pylori:a need for caution and re-evaluation

Screening for Helicobacter pylori in dyspeptic patients may improve selectivity for gastroscopy. Rapid serological tests based on ELISA technique are cheap, readily available and simple to use in the clinical setting. However local evaluation is essential in order to validate these techniques. Fifty-six dyspeptic patients (aged less than 45 yr) had a rapid serological test (Helisal) performed prior to gastroscopy. At gastroscopy H. pylori status was assessed using culture and histology. The Helisal sensitivity was 80 per cent, specificity 82 per cent. Screening patients with the Helisal test would have missed 6 patients with peptic ulcer disease and 2 with oesophagitis. The Helisal test did not perform satisfactorily as a screening test in selection of patients for gastroscopy.