Helicobacter pylori infection and UBT-13C values are associated with changes in body mass index in children and adults / La infección por Helicobacter pylori y los valores de UBT-13C se asocian con el índice de masa corporal en niños y adultos

BACKGROUND: The urea breath test (UBT-13C) is a non-invasive technique that allows the diagnosis and confirmation of eradication of Helicobacter pylori infection. Aim: To evaluate H. pylori positivity and values of UBT-13C among infected Chilean children and adults, and to analyze its variation in relation to sex, nutritional status, and age of the patients. Material and Methods: Retrospective study of 1141 patients aged 6 to 94 years, with an indication for a UBT-13C either for diagnosis or for confirmation of eradication of H. pylori infection. 13C enrichment was measured using an infrared spectrometer calculating the delta 13C values before and after the ingestion of 13C marked urea. The clinical data of the patients were obtained at the time of the examination. Results: We included 241 children and 900 adults. Infected children obtained lower UBT-13C delta values than infected adults (16.1 ± 8.7 and 37 ± 52.9, respectively). The rates of infection were higher in males who were recruited for diagnosis. Significant differences were obtained between positivity for H. pylori in overweight and obese children but not adults. UBT-13C titers were significantly associated with the body mass index (BMI) only in adults. Conclusions: H. pylori infection rates are similar between sexes and are higher in children probably because of selection bias. In children, H. pylori positivity is associated with higher BMI and excess malnutrition although with similar UBT-13C values. In adults, H. pylori infection is not related with BMI, but a higher BMI impacts UBT-13C titers.

ANTECEDENTES: La prueba de aliento con urea (UBT-13C) es una técnica no invasiva que permite el diagnóstico y confirmación de erradicación de la infección por Helicobacter pylori. Objetivo: Evaluar los valores de UBT- 13C en niños y adultos chilenos infectados y analizar su variación en relación al sexo, diagnóstico nutricional y edad de los pacientes. Material y Métodos: Estudio retrospectivo de 1.141 pacientes de 6 a 94 años. El enriquecimiento de13C se midió usando un espectrómetro de infrarrojos, calculando el delta 13C antes y después de la ingesta de urea marcada con 13C. Los datos clínicos de los pacientes se obtuvieron al momento del examen. Resultados: Incluimos 241 niños y 900 adultos con valores delta de UBT-13C de 16,1 ± 8,7 frente a 37 ± 52,9, respectivamente. Las tasas de infección fueron mayores en los hombres reclutados para el diagnóstico. Se obtuvieron diferencias significativas entre la positividad para H. pylori en niños con sobrepeso y obesidad, pero no en adultos. Los títulos de UBT-13C se asociaron significativamente con el índice de masa corporal (IMC) solo en adultos. Conclusiones: Las tasas de infección por H. pylori son similares entre los sexos y aumentan en los niños probablemente debido al sesgo de selección. En niños, la positividad para H. pylori se asocia con un IMC más alto y malnutrición por exceso, aunque con valores similares de UBT-13C. En los adultos, la infección por H. pylori no se relaciona con el IMC ni con la obesidad, pero el aumento del IMC afecta los títulos de UBT-13C.

MNPmApp: An image analysis tool to quantify mononuclear phagocyte distribution in mucosal tissues.

Mononuclear phagocytes (MNPs) such as dendritic cells and macrophages perform key sentinel functions in mucosal tissues and are responsible for inducing and maintaining adaptive immune responses to mucosal pathogens. Positioning of MNPs at the epithelial interface facilitates their access to luminally-derived antigens and regulates MNP function through soluble mediators or surface receptor interactions. Therefore, accurately quantifying the distribution of MNPs within mucosal tissues as well as their spatial relationship with other cells is important to infer functional cellular interactions in health and disease. In this study, we developed and validated a MATLAB-based tissue cytometry platform, termed "MNP mapping application" (MNPmApp), that performs high throughput analyses of MNP density and distribution in the gastrointestinal mucosa based on digital multicolor fluorescence microscopy images and that integrates a Monte Carlo modeling feature to assess randomness of MNP distribution. MNPmApp identified MNPs in tissue sections of the human gastric mucosa with 98 ± 2% specificity and 76 ± 15% sensitivity for HLA-DR+ MNPs and 98 ± 1% specificity and 85 ± 12% sensitivity for CD11c+ MNPs. Monte Carlo modeling revealed that mean MNP-MNP distances for both HLA-DR+ and CD11c+ MNPs were significantly lower than anticipated based on random cell placement, whereas MNP-epithelial distances were similar to randomly placed cells. Surprisingly, H. pylori infection had no significant impact on the number of HLA-DR and CD11c MNPs or their distribution within the gastric lamina propria. However, our study demonstrated that MNPmApp is a reliable and user-friendly tool for unbiased quantitation of MNPs and their distribution at mucosal sites.

Helicobacter pylori infection and UBT-13C values are associated with changes in body mass index in children and adults.

BACKGROUND: The urea breath test (UBT-13C) is a non-invasive technique that allows the diagnosis and confirmation of eradication of Helicobacter pylori infection. AIM: To evaluate H. pylori positivity and values of UBT-13C among infected Chilean children and adults, and to analyze its variation in relation to sex, nutritional status, and age of the patients. MATERIAL AND METHODS: Retrospective study of 1141 patients aged 6 to 94 years, with an indication for a UBT-13C either for diagnosis or for confirmation of eradication of H. pylori infection. 13C enrichment was measured using an infrared spectrometer calculating the delta 13C values before and after the ingestion of 13C marked urea. The clinical data of the patients were obtained at the time of the examination. RESULTS: We included 241 children and 900 adults. Infected children obtained lower UBT-13C delta values than infected adults (16.1 ± 8.7 and 37 ± 52.9, respectively). The rates of infection were higher in males who were recruited for diagnosis. Significant differences were obtained between positivity for H. pylori in overweight and obese children but not adults. UBT-13C titers were significantly associated with the body mass index (BMI) only in adults. CONCLUSIONS: H. pylori infection rates are similar between sexes and are higher in children probably because of selection bias. In children, H. pylori positivity is associated with higher BMI and excess malnutrition although with similar UBT-13C values. In adults, H. pylori infection is not related with BMI, but a higher BMI impacts UBT-13C titers.

Interactions between H. pylori and the Gastric Microbiome: Impact on Gastric Homeostasis and Disease.

Like many seemingly inhospitable environments on our planet, the highly acidic human stomach harbors a diverse bacterial microflora. The best-known member of the human gastric flora, Helicobacter pylori, causes a number of gastric diseases, including peptic ulcer disease and gastric adenocarcinoma. In the absence of Helicobacter pylori infection, the gastric microbiota displays some features similar to the oral cavity with Firmicutes the most common phylum, followed by Proteobacteria and Bacteroidetes. When present, H. pylori dominates the gastric microbiome and reduces diversity and composition of other taxa. The composition of the gastric microbiome also is altered in the setting of proton pump inhibitor therapy and gastric neoplasia. This review summarizes foundational and recent studies that have investigated the composition of the human gastric microbiome in a variety of patient groups, with a focus on potential mechanisms involved in regulation of gastric microbial community structure.

Naturalization of the microbiota developmental trajectory of Cesarean-born neonates after vaginal seeding.

BACKGROUND: Early microbiota perturbations are associated with disorders that involve immunological underpinnings. Cesarean section (CS)-born babies show altered microbiota development in relation to babies born vaginally. Here we present the first statistically powered longitudinal study to determine the effect of restoring exposure to maternal vaginal fluids after CS birth. METHODS: Using 16S rRNA gene sequencing, we followed the microbial trajectories of multiple body sites in 177 babies over the first year of life; 98 were born vaginally, and 79 were born by CS, of whom 30 were swabbed with a maternal vaginal gauze right after birth. FINDINGS: Compositional tensor factorization analysis confirmed that microbiota trajectories of exposed CS-born babies aligned more closely with that of vaginally born babies. Interestingly, the majority of amplicon sequence variants from maternal vaginal microbiomes on the day of birth were shared with other maternal sites, in contrast to non-pregnant women from the Human Microbiome Project (HMP) study. CONCLUSIONS: The results of this observational study prompt urgent randomized clinical trials to test whether microbial restoration reduces the increased disease risk associated with CS birth and the underlying mechanisms. It also provides evidence of the pluripotential nature of maternal vaginal fluids to provide pioneer bacterial colonizers for the newborn body sites. This is the first study showing long-term naturalization of the microbiota of CS-born infants by restoring microbial exposure at birth. FUNDING: C&D, Emch Fund, CIFAR, Chilean CONICYT and SOCHIPE, Norwegian Institute of Public Health, Emerald Foundation, NIH, National Institute of Justice, Janssen.

[Normal values of eosinophils in gastric and duodenal mucosa of children referred to upper gastrointestinal endoscopy]. / Valores de normalidad de eosinófilos en mucosa gástrica y duodenal de niños referidos a endoscopía digestiva alta.

INTRODUCTION: With the increasing incidence of food allergies, the presence of eosinophils (Eos) in the gastrointes tinal mucosa has received increased attention, particularly in the esophagus and colon. However, normal values for the Eos count in the stomach and duodenum in pediatric patients are still limited. THE OBJECTIVE: of this study was to estimate Eos reference values in stomach and duodenal biopsies of children referred to upper gastrointestinal endoscopy. PATIENTS AND METHODS: Cross-sectional study of biopsies from symptomatic children referred to upper gastrointestinal endoscopy. The endoscopic report, Rapid Urease Test for the presence of H. pylori, and the quantitative histological evaluation (number of cells/HFP, high power field) were analyzed. The Eos distribution is described as mean and standard deviation, and also as percentiles since the counts did not have a normal distribution. Statistical analysis included x2 test, Wilcoxon test, analysis of variance, and linear regression curves were evaluated as appropriate. RESULTS: Of the 170 patients referred to endoscopy, 72 met "normal" criteria (normal endoscopy in macroscopic analysis, negative Rapid Urease Test, and normal biop sy). The median age was 11 years (range 4-16), and 68% were girls. The Eos count (mean ± 1SD) in gastric antrum (n = 72) was 1.13 ± 1.79 Eos/HPF; in gastric body (n = 27), 1.06 ± 1.79 Eos/HPF; and in duodenum (n = 30), 10.44 ± 7.09 Eos/HPF. There were no significant differences by age and sex, or by H. pylori infection (p = 0.095). CONCLUSIONS: We propose an Eos count of 0-3 Eos/HPF for the gastric body, 0-3 Eos/HPF in the antrum, and 3-17 Eos/HPF in the duodenum as a normal range for gastric mucosa in children. This study suggests that in areas with a high prevalence of H. pylori infec tion, the count of Eos does not seem to be a distinctive element and that Eos are commonly present in the gastroduodenal mucosa.

[Revista Chilena de Pediatría/Andes Pediatrica in the new millennium. Bibliometric analysis]. / Revista Chilena de Pediatría/Andes Pediatrica en el nuevo milenio. Análisis bibliométrico.

INTRODUCTION: Andes Pediatrica/Revista Chilena de Pediatría (AP/RChP), maintains a document profile that covers all scientific publication formats, from Original Articles (OAs) to Letters to the Editor. Adequate editorial planning requires a long-term bibliometric analysis. OBJECTIVE: To describe the profile of OAs published in AP/RChP in the last two decades. METHODOLOGY: From a controlled vocabulary list, the thematic and methodological descriptors of the documents from 2000 to 2020 were standardi zed. Nationality, sex, and profession of the authors, document typology, and design of the OAs were analyzed, as well as the descriptors cited in Google Scholar and the most visited descriptors on the journal's website in recent years. RESULTS: 1738 manuscripts were published, 580 (33.4%) were OAs, with an increase from 59 to 129 OAs between the first and last three years. The average number of authors was higher for OAs (4.7) than for non-originals (3.0). In 2020, there were nine multicenter collaborations from different countries. The number of OAs by foreign authors increased from 3.3% to 28.7%, the first authorship by non-medical professionals increased from 15% to 31%, and there was a predominance of female first authors (ratio 1.4/1). Of the OAs, 9.1% were experimental, 3.3% were qualitative and the rest were quantitative observational. The most published descriptors were Nutrition, Infectious Diseases, Neonatology, and Pneumonology, while the most cited descriptors were Nutrition, Neonatology, and Oral Health, with no trend among the most visited. 44% of the most cited articles and 35% of the most visited articles were OAs. CONCLUSIONS: A significant increase in published OAs stands out, with a low frequency of experimental designs. Authors of different na tionalities and professions participated. OAs represent one-third of the visits and almost half of the citations, with no correlation between the most published and most cited descriptors.

Adaptación a la realidad de Latinoamérica de la Guía Clínica NASPGHAN/ESPGHAN 2016 sobre Diagnóstico, Prevención y Tratamiento de Infección por Helicobacter pylori en Pediatría / Adaptation to the reality of Latin America of the NASPGHAN/ESPGHAN 2016 Guidelines on the Diagnosis, Prevention and Treatment of Helicobacter pylori Infection in Pediatrics

Resumen: Introducción: Las últimas guías clínicas conjuntas de NASPGHAN y ESPGHAN en relación a la infección por H. pylori publicadas el año 2016, contienen 20 afirmaciones que han sido cuestionadas en la práctica respecto a su aplicabilidad en Latinoamérica (LA); en particular en relación a la preven ción del cáncer gástrico. Métodos: Se realizó un análisis crítico de la literatura, con especial énfasis en datos de LA y se estableció el nivel de evidencia y nivel de recomendación de las afirmaciones mas controversiales de las Guías Conjuntas. Se realizaron 2 rondas de votación de acuerdo a la técnica Delfi de consenso y se utilizó escala de Likert (de 0 a 4) para establecer el "grado de acuerdo" entre un grupo de expertos de SLAGHNP. Resultados: Existen pocos estudios en relación a diagnóstico, efectividad de tratamiento y susceptibilidad a antibióticos de H. pylori en pacientes pediátricos de LA. En base a estos estudios, extrapolaciones de estudios de adultos y la experiencia clínica del panel de expertos participantes, se realizan las siguientes recomendaciones. Recomendamos la toma de biopsias para test rápido de ureasa e histología (y muestras para cultivo o técnicas moleculares, cuando estén disponibles) durante la endoscopia digestiva alta sólo si en caso de confirmar la infección por H. pylori, se indicará tratamiento de erradicación. Recomendamos que centros regionales seleccio nados realicen estudios de sensibilidad/resistencia antimicrobiana para H. pylori y así actúen como centros de referencia para toda LA. En caso de falla de erradicación de H. pylori con tratamiento de primera línea, recomendamos tratamiento empírico con terapia cuádruple con inhibidor de bomba de protones, amoxicilina, metronidazol y bismuto por 14 días. En caso de falla de erradicación con el esquema de segunda línea, se recomienda indicar un tratamiento individualizado considerando la edad del paciente, el esquema indicado previamente y la sensibilidad antibiótica de la cepa, lo que implica realizar una nueva endoscopía con extracción de muestra para cultivo y antibiograma o es tudio molecular de resistencia. En niños sintomáticos referidos a endoscopía que tengan antecedente de familiar de primer o segundo grado con cáncer gástrico, se recomienda considerar la búsqueda de H. pylori mediante técnica directa durante la endoscopia (y erradicarlo cuando es detectado). Con clusiones: La evidencia apoya mayoritariamente los conceptos generales de las Guías NASPGHAN/ ESPGHAN 2016, pero es necesario adaptarlas a la realidad de LA, con énfasis en el desarrollo de centros regionales para el estudio de sensibilidad a antibióticos y mejorar la correcta selección del tratamiento de erradicación. En niños sintomáticos con antecedente familiar de primer o segundo grado de cáncer gástrico, se debe considerar la búsqueda y erradicación de H. pylori.

Abstract: Introduction: The latest joint H. pylori NASPGHAN and ESPGHAN clinical guidelines published in 2016, contain 20 statements that have been questioned in practice regarding their applicability in Latin America (LA); in particular in relation to gastric cancer prevention. Methods: We conduc ted a critical analysis of the literature, with special emphasis on LA data and established the level of evidence and level of recommendation of the most controversial claims in the Joint Guidelines. Two rounds of voting were conducted according to the Delphi consensus technique and a Likert scale (from 0 to 4) was used to establish the "degree of agreement" among a panel of SLAGHNP ex perts. Results: There are few studies regarding diagnosis, treatment effectiveness and susceptibility to antibiotics of H. pylori in pediatric patients of LA. Based on these studies, extrapolations from adult studies, and the clinical experience of the participating expert panel, the following recom mendations are made. We recommend taking biopsies for rapid urease and histology testing (and samples for culture or molecular techniques, when available) during upper endoscopy only if in case of confirmed H. pylori infection, eradication treatment will be indicated. We recommend that selected regional centers conduct antimicrobial sensitivity/resistance studies for H. pylori and thus act as reference centers for all LA. In case of failure to eradicate H. pylori with first-line treatment, we recommend empirical treatment with quadruple therapy with proton pump inhibitor, amoxi cillin, metronidazole, and bismuth for 14 days. In case of eradication failure with the second line scheme, it is recommended to indicate an individualized treatment considering the age of the pa tient, the previously indicated scheme and the antibiotic sensitivity of the strain, which implies performing a new endoscopy with sample extraction for culture and antibiogram or molecular resistance study. In symptomatic children referred to endoscopy who have a history of first or se cond degree family members with gastric cancer, it is recommended to consider the search for H. pylori by direct technique during endoscopy (and eradicate it when detected). Conclusions: The evidence supports most of the general concepts of the NASPGHAN/ESPGHAN 2016 Guidelines, but it is necessary to adapt them to the reality of LA, with emphasis on the development of regional centers for the study of antibiotic sensitivity and to improve the correct selection of the eradication treatment. In symptomatic children with a family history of first or second degree gastric cancer, the search for and eradication of H. pylori should be considered.

Maternal H. pylori is associated with differential fecal microbiota in infants born by vaginal delivery.

Helicobacter pylori colonization may affect the mucosal immune system through modification of microbiota composition and their interactions with the host. We hypothesized that maternal H. pylori status affects the maternal intestinal microbiota of both mother and newborn. In this study, we determine the structure of the fecal microbiota in mothers and neonates according to maternal H. pylori status and delivery mode. We included 22 mothers and H. pylori infection was determined by fecal antigen test. Eleven mothers (50%) were H. pylori-positive (7 delivering vaginally and 4 by C-section), and 11 were negative (6 delivering vaginally and 5 by C-section). Stool samples were obtained from mothers and infants and the fecal DNA was sequenced. The fecal microbiota from mothers and their babies differed by the maternal H. pylori status, only in vaginal birth, not in C-section delivery. All 22 infants tested negative for fecal H. pylori at 15 days of age, but those born vaginally -and not those by C-section- showed differences in the infant microbiota by maternal H. pylori status (PERMANOVA, p = 0.01), with higher abundance of Enterobacteriaceae and Veillonella, in those born to H. pylori-positive mothers. In conclusion, the structure of the infant fecal microbiota is affected by the maternal H. pylori status only in infants born vaginally, suggesting that the effect could be mediated by labor and birth exposures.

Early origins of allergy and asthma (ARIES): study protocol for a prospective prenatal birth cohort in Chile.

BACKGROUND: Growing evidence shows that atopic dermatitis (AD), food allergy (FA), allergic rhinitis, and asthma are largely determined during the first 1000 days (time elapsed from conception to the 2nd birthday). The ARIES birth cohort aims to determine prenatal and perinatal conditions, as well as genetic and epigenetic factors, that participate in the early setting of immune responses, and the role of these in the later determination of the risk of allergic diseases and asthma in the offspring. METHODS: We have designed a birth cohort of 250 families with prenatal recruitment (~ 14 weeks). We will genotype relevant allergy/asthma-associated variants in trios and will perform immunophenotyping and evaluation of allergy biomarkers in cord blood. At 1 and 2 years of age we will assess if infants have developed allergic sensitization, AD, FA, as well as biomarkers of asthma including the asthma predictive index. We will also evaluate how maternal conditions modify immune programming through epigenetic modifications and will then depict newborn epigenetic cues of allergy/asthma risk. Next, we will assess composition/diversity of maternal gut, placenta, breastmilk and infant gut microbiome and their association with immunophenotype and biomarkers at birth, and clinical outcomes at age 1 and 2. Finally, we plan to assess how environmental exposures (perinatal outdoor and indoor pollution, allergens and endotoxin) affect the incidence of allergic sensitization, AD, FA, and risk of asthma. DISCUSSION: The in-depth study of the ARIES birth cohort shall provide crucial information to understand the rising incidence of allergies and asthma in developing countries, and hopefully provide cues on how to prevent and treat these diseases. TRIAL REGISTRATION: clinicaltrials.gov NCT04186949, retrospectively registered on December 5, 2019.

High Helicobacter pylori Bacterial Load and Low Cytokine Expression Levels Are Associated with Nodular Gastropathy.

BACKGROUND AND AIMS: Nodular gastropathy (NG) is an inflammatory condition of the gastric mucosa characterized by the endoscopic detection of multiple millimeter protrusions. A strong association between NG and Helicobacter pylori and a possible role of NG as a risk factor for undifferentiated gastric cancer have been described. The aim of this study was to characterize the pathogenic and inflammatory profile of patients with NG. METHODS: Adult patients referred for upper gastrointestinal endoscopy were prospectively enrolled in this study. H. pylori infection status was determined by rapid urease test. Biopsies were stained with hematoxylin-eosin. Sydney and OLGA scores were used to assess gastritis characteristics and gastric cancer risk. PCR analysis was performed to determine bacterial load and virulence factors CagA (and its EPIYA motifs) and VacA alleles. Finally, gastric mucosa cytokine gene expression (IL-8, IL-1ß, and TNF-α) was determined by real-time RT-PCR. RESULTS: Forty-eight patients, mean age of 36 years, were recruited. All NG patients were infected by H. pylori. OLGA score was similar in both groups (NG patients and non-NG patients). NG patients had higher bacterial load in the gastric corpus (p = 0.01) and significantly less pro-inflammatory cytokine levels than non-NG infected patients (p = 0.01). CONCLUSIONS: In our study, NG is not associated with preneoplastic lesions. An increase in bacterial load without a concomitant increase in mucosal inflammatory cytokine responses in H. pylori-infected subjects with NG may represent a general dampening of immune responses or an additional mechanism of H. pylori active immune evasion.

[Adaptation to the reality of Latin America of the NASPGHAN/ESPGHAN 2016 Guidelines on the Diagnosis, Prevention and Treatment of Helicobacter pylori Infection in Pediatrics]. / Adaptación a la realidad de Latinoamérica de la Guía Clínica NASPGHAN/ESPGHAN 2016 sobre Diagnóstico, Prevención y Tratamiento de Infección por Helicobacter pylori en Pediatría.

INTRODUCTION: The latest joint H. pylori NASPGHAN and ESPGHAN clinical guidelines published in 2016, contain 20 statements that have been questioned in practice regarding their applicability in Latin America (LA); in particular in relation to gastric cancer prevention. METHODS: We conduc ted a critical analysis of the literature, with special emphasis on LA data and established the level of evidence and level of recommendation of the most controversial claims in the Joint Guidelines. Two rounds of voting were conducted according to the Delphi consensus technique and a Likert scale (from 0 to 4) was used to establish the "degree of agreement" among a panel of SLAGHNP ex perts. RESULTS: There are few studies regarding diagnosis, treatment effectiveness and susceptibility to antibiotics of H. pylori in pediatric patients of LA. Based on these studies, extrapolations from adult studies, and the clinical experience of the participating expert panel, the following recom mendations are made. We recommend taking biopsies for rapid urease and histology testing (and samples for culture or molecular techniques, when available) during upper endoscopy only if in case of confirmed H. pylori infection, eradication treatment will be indicated. We recommend that selected regional centers conduct antimicrobial sensitivity/resistance studies for H. pylori and thus act as reference centers for all LA. In case of failure to eradicate H. pylori with first-line treatment, we recommend empirical treatment with quadruple therapy with proton pump inhibitor, amoxi cillin, metronidazole, and bismuth for 14 days. In case of eradication failure with the second line scheme, it is recommended to indicate an individualized treatment considering the age of the pa tient, the previously indicated scheme and the antibiotic sensitivity of the strain, which implies performing a new endoscopy with sample extraction for culture and antibiogram or molecular resistance study. In symptomatic children referred to endoscopy who have a history of first or se cond degree family members with gastric cancer, it is recommended to consider the search for H. pylori by direct technique during endoscopy (and eradicate it when detected). CONCLUSIONS: The evidence supports most of the general concepts of the NASPGHAN/ESPGHAN 2016 Guidelines, but it is necessary to adapt them to the reality of LA, with emphasis on the development of regional centers for the study of antibiotic sensitivity and to improve the correct selection of the eradication treatment. In symptomatic children with a family history of first or second degree gastric cancer, the search for and eradication of H. pylori should be considered.