Postbióticos: un nuevo miembro en la familia de los bióticos / Postbiotics: A new member in the biotics family

Los postbióticos fueron definidos en 2021 por la Asociación Científica Internacional de Probióticos y Prebióticos (ISAPP) como "una preparación de microorganismos inanimados y/o sus componentes celulares capaces de conferir un efecto benéfico al hospedador". El campo de los postbióticos es un área nueva dentro de la familia de los bióticos; se han desarrollado ya numerosos productos con aplicaciones clínicas, como la estimulación inmunológica, el manejo de diarreas en niños y adultos, el abordaje del intestino irritable, además de tres fórmulas infantiles. En particular, las fórmulas infantiles con postbióticos obtenidos a partir de la fermentación de la leche con Bifidobacterium breve C50 y Streptococcus thermophilus O65, y sus metabolitos, incluido el oligosacárido 3'-GL, han demostrado seguridad y contribución al desarrollo de la microbiota intestinal y el sistema inmune asociado al intestino. Estas modificaciones contribuyen a la prevención y el manejo de los trastornos funcionales digestivos del lactante.

Postbiotics were defined in 2021 by the International Scientific Association for Probiotics and Prebiotics (ISAPP) as a "preparation of inanimate microorganisms and/or their cellular components that confers a health benefit to the host." The field of postbiotics is a new area within the biotics family; numerous products have already been developed for clinical applications, such as immune stimulation, the management of diarrhea in children and adults, the management of irritable bowel syndrome, and 3 infant formulas. In particular, infant formulas with postbiotics obtained from milk fermented with Bifidobacterium breve C50 and Streptococcus thermophilus O65 ­and their metabolites­, including the oligosaccharide 3'-GL, have demonstrated to be safe and to contribute to the development of the gut microbiota and the gutassociated immune system. These modifications help to prevent and manage functional gastrointestinal disorders in infants.

Genome-based diagnostic of MDR Escherichia coli ONT:H19 ST10955 causing human gastrointestinal infection.

This study focuses on the genomic characterization of a multidrug-resistant Escherichia coli strain responsible for a severe gastrointestinal infection in a 33-year-old male. The patient initially received sulfamethoxazole/trimethoprim treatment, which proved ineffective. Fecal culture confirmed the presence of E. coli displaying a MDR profile to ampicillin, nalidixic acid, ciprofloxacin, sulfamethoxazole, trimethoprim, and tetracycline. Serotyping identified the strain as ONT:H19. Virulence analysis indicated a highly virulent profile with numerous virulence markers. Plasmid analysis uncovered various plasmids carrying both antimicrobial resistance and virulence genes. MLST assigned the strain to ST10955. Phylogenomic analysis revealed similarity to an older Brazilian isolate, suggesting the persistence of a common lineage with evolving antimicrobial resistance. This report highlights the first identification of a multidrug-resistant ST10955 E. coli strain with a wide resistome and virulence potential, emphasizing the importance of ongoing surveillance of E. coli strains due to their potential for severe infections, resistance development, and virulence.

Microbiota intestinal y cólicos infantiles: ¿hay lugar para los prebióticos, probióticos y posbióticos? / Gut Microbiota and Infant Colic: is there a Place for Prebiotics, Probiotics, and Postbiotics?

El consumo de probióticos, prebióticos y posbióticos, o su combinación, puede contribuir a mantener una microbiota intestinal saludable ya que permite la regulación de su disbiosis en el caso de algunas enfermedades o trastornos, principalmente en los trastornos gastrointestinales funcionales (TGIF). El microbioma intestinal es protagonista esencial en la fisiopatología de los TGIF a través de sus funciones metabólicas y nutricionales, el mantenimiento de la integridad de la mucosa intestinal y la regulación de la respuesta inmunitaria. Las investigaciones realizadas hasta la fecha indican que los probióticos, prebióticos y posbióticos pueden tener efectos inmunomoduladores directos y clínicamente relevantes. Existen pruebas del uso de esta familia de bióticos en individuos sanos para mejorar la salud general y aliviar los síntomas en una serie de enfermedades como los cólicos infantiles. La colonización y establecimiento de la microbiota comienza en el momento del nacimiento; los primeros 2-3 años de vida son fundamentales para el desarrollo de una comunidad microbiana abundante y diversa. Diversos estudios científicos realizados mediante técnicas tradicionales dependientes de cultivo y más recientemente por técnicas moleculares han observado diferencias en las poblaciones bacterianas de bebés sanos y aquellos que sufren TGIF, estos últimos caracterizados por un aumento de especies patógenas y una menor población de bifidobacterias y lactobacilos, en comparación con los primeros. En tal contexto, se considera que la microbiota intestinal como protagonista en el desarrollo de esos trastornos, entre ellos los cólicos infantiles, a través de sus funciones metabólicas, nutricionales, de mantenimiento de la integridad de la mucosa intestinal y regulación de la respuesta inmunitaria. Esto ha abierto la puerta al estudio de la utilización de prebióticos, probióticos y posbióticos en el tratamiento y/o prevención de los TGIF infantiles. El parto vaginal y de término así como la lactancia son fundamentales en la constitución de una microbiota saludable. Como herramientas de apoyo, existen estudios de eficacia que sustentan la administración de esta familia de bióticos, principalmente en los casos en que la lactancia no sea posible o esté limitada. (AU)

The consumption of probiotics, prebiotics, and postbiotics, or a combination of them, can contribute to maintaining a healthy intestinal microbiota as it allows the regulation of its dysbiosis in the case of some diseases or disorders, mainly in functional gastrointestinal disorders (FGIDs). The gut microbiome is an essential player in the pathophysiology of FGIDs through its metabolic and nutritional functions, the maintenance of intestinal mucosal integrity, and the regulation of the immune response. Research results thus far indicate that probiotics, prebiotics, and postbiotics may have direct and clinically relevant immunomodulatory effects. There is evidence regarding the prescription of this family of biotics in healthy individuals to improve overall health and alleviate symptoms in many conditions like infantile colic. The colonization and microbiota establishment begins at birth; the first 2-3 years of life are critical for developing an abundant and diverse microbial community. Several scientific studies performed by traditional culture-dependent techniques and more recently by molecular techniques have observed differences in the bacterial populations of healthy infants and those suffering from FGIDs, the latter characterized by an increase in pathogenic species and a lower population of bifidobacteria and lactobacilli, compared to the former. In this context, the intestinal microbiota plays a leading role in the onset of these disorders, including infantile colic, through its metabolic and nutritional functions, maintenance of the integrity of the intestinal mucosa, and regulation of the immune response. That has opened the door to the study of prebiotics, probiotics, and postbiotics usage in the treatment and or prevention of infantile FGIDs. Vaginal and term delivery and breastfeeding are fundamental in the constitution of a healthy microbiota. As supportive tools, there are efficacy studies that support the administration of this family of biotics, mainly in cases where lactation is not possible or is limited.

Wastewater-Based Epidemiology of Enteric Viruses and Surveillance of Acute Gastrointestinal Illness Outbreaks in a Resource-Limited Region.

Acute gastrointestinal illness (AGI) continues to be an important cause of morbidity and mortality among all ages. This study applied the principles of wastewater-based epidemiology for the preventive identification of potential outbreaks of acute viral gastroenteritis and hepatitis A by analyzing the presence of human enteric viruses in influents of small municipal wastewater treatment plants (WWTPs) handling domestic sewage, together with public health reports of acute diarrheal and hepatitis A disease in Costa Rica during 2013. Raw wastewater samples were collected during four seasonal periods with different rainfall levels. The presence of five human enteric viruses (rotavirus A, norovirus GI, norovirus GII, enterovirus, and hepatitis A virus) was studied by endpoint and real-time polymerase chain reaction in influents of five WWTPs. Cases of AGI were analyzed using historical public health reports of endemic levels and quartile ranges for each administrative and territorial area where the WWTPs are located and for its surrounding counties. A tendency for a higher rate of positive viral tests was present 1 week before an increase of AGI cases. Epidemiological weeks categorized as Outbreak (above the 75th percentile) and Success (below the 25th percentile) showed statistically significant differences in terms of positive viral test rates (Wilcoxon test, P = 0.05). Virological monitoring of wastewater in small WWTPs is an appropriate model for epidemiological surveillance of diarrheal and hepatitis A diseases in low- and middle-resource countries.

Effects of Essential Oils of Elettaria cardamomum Grown in India and Guatemala on Gram-Negative Bacteria and Gastrointestinal Disorders.

The present study examined the chemical composition and antimicrobial and gastrointestinal activity of the essential oils of Elettaria cardamomum (L.) Maton harvested in India (EC-I) and Guatemala (EC-G). Monoterpenes were present in higher concentration in EC-I (83.24%) than in EC-G (73.03%), whereas sesquiterpenes were present in a higher concentration in EC-G (18.35%) than in EC-I (9.27%). Minimum inhibitory concentrations (MICs) of 0.5 and 0.25 mg/mL were demonstrated against Pseudomonas aeruginosa in EC-G and EC-I, respectively, whereas MICs of 1 and 0.5 mg/mL were demonstrated against Escherichia coli in EC-G and EC-I, respectively. The treatment with control had the highest kill-time potential, whereas the treatment with oils had shorter kill-time. EC-I was observed to be more potent in the castor oil-induced diarrhea model than EC-G. At 100 and 200 mg/kg, P.O., EC-I exhibited 40% and 80% protection, respectively, and EC-G exhibited 20% and 60% protection, respectively, in mice, whereas loperamide (10 mg/kg, i.p., positive control) exhibited 100% protection. In the in vitro experiments, EC-I inhibited both carbachol (CCh, 1 µM) and high K+ (80 mM)-induced contractions at significantly lower concentrations than EC-G. Thus, EC-I significantly inhibited P. aeruginosa and E. coli and exhibited more potent antidiarrheal and antispasmodic effects than EC-G.

Impact of Multiplex Testing on the Identification of Pediatric Clostridiodes Difficile.

OBJECTIVES: To evaluate whether the implementation of a multiplex gastrointestinal pathogen panel (GIP) was associated with changes in Clostridioides difficile (C difficile) testing and detection rates. STUDY DESIGN: We conducted an observational study using interrupted time series analysis and included pediatric patients with testing capable of detecting C difficile. From 2013 to 2015 ("conventional diagnostic era"), stool testing included C difficile-selective polymerase chain reaction and other pathogen-specific tests. From 2015 to 2017 ("GIP era"), C difficile polymerase chain reaction was available along with the GIP, which detected 22 pathogens including C difficile, and replaced the need for additional tests. Outcomes included C difficile testing and detection rates in ambulatory, emergency department, and inpatient settings. RESULTS: There were 6841 tests performed and 1214 C difficile positive results. Across the 3 settings, GIP era had significantly higher C difficile testing (1.7-2.3 times higher) and C difficile detection rates (1.9-3.4 times higher) compared with conventional diagnostic era. After adjusting for the number of tests performed, detection rates were no longer significantly different. Of C difficile positive GIPs, 31% were coinfected with another organism. With GIP testing, patients 1 year of age had a significantly higher C difficile percent positivity than 2-year-old (P = .02) and 3- to 18-year-old children (P < .01). Younger children with C difficile were more likely to be coinfected (P < .01). CONCLUSIONS: Introducing a multiplex panel led to increased C difficile testing, which resulted in increased C difficile detection rates and potential identification and treatment of colonized patients. This highlights an important target for diagnostic stewardship and the challenges associated with multiplex testing.

THE IMPACT OF SMALL INTESTINAL BACTERIAL OVERGROWTH ON THE GROWTH OF CHILDREN AND ADOLESCENTS.

OBJECTIVE: To evaluate the association between small intestinal bacterial overgrowth (SIBO) and weight and height impairment in children and adolescents with gastroenterology diseases. METHODS: Observational and retrospective study. All 162 patients aged less than 19 years old who underwent breath test in search of SIBO between 2011 and 2016 were studied. Breath test was collected after the intake of 10 grams of lactulose. The concentration of hydrogen and methane was measured for 180 minutes after the beginning of the test by 12i QuinTronMicroLyzer device. RESULTS: SIBO was identified in 51 (31.5%) patients. There was no difference between the age of those with (mean=8.7y.o; 25th and 75th percentile: 4.6 and 11.3) and without (mean=7.9y.o 25th and 75th percentile: 4.8 and 12.2) SIBO (p=0.910). There was no association between gender and SIBO (male 26.3% vs. female 36.3%, p=1.00). A lower median of height-for-age Z score (mean=-1.32; 25th and 75th percentile: -2.12 and -0.08 vs. mean=-0.59; 25th and 75th percentile: -1.57 and 0.22; p=0.04) was demonstrated in children with SIBO when compared with children without it. There was no difference between the BMI-for-age Z score of patients with (mean=-0.48) and without SIBO (mean=-0.06) (p=0.106). The BMI of patients with SIBO (median=15.39) was lower than of those without it (median=16.06); however, the statistical analysis was not significant (p=0.052). The weight-for-age Z score was lower in patients with SIBO (mean=-0.96) than in those without SIBO (mean=-0.22) (p=0.02). CONCLUSIONS: Children and adolescents with SBIO associated with diseases of the gastrointestinal tract have lower weight and height values.

Dysbiosis Signatures of Fecal Microbiota in South African Infants with Respiratory, Gastrointestinal, and Other Diseases.

OBJECTIVE: To determine the association between the fecal microbiota diversity of the infants with different disease conditions, and vitamin A supplementation, antibiotic, and deworming therapies. STUDY DESIGN: In this case-control study, the bacterial community variations and the potential pathogens were identified through 16S ribosomal RNA gene-based amplicon sequencing and quantitative insights into microbial ecology pipeline in fecal samples. The participants were South African infants (mean age, 16 ± 8 months; 17 male and 17 female) hospitalized and diagnosed with gastrointestinal, respiratory, and other diseases. RESULTS: The top phyla of the infants with respiratory disease were Proteobacteria, followed by Firmicutes, which were equally abundant in gastrointestinal disease. A significant difference in Shannon (alpha) diversity index (95% CI, 2.6-4.4; P = .008), among the microbiota of the fecal samples categorized by disease conditions, was observed. In beta diversity analysis of fecal microbiota, remarkable variations were found within the groups of deworming therapy (95% CI, 0.40-0.90; P = .033), disease conditions (95% CI, 0.44-0.86; P < .012) through unweighted and antibiotic therapy (95% CI, 0.20-0.75; P = .007), vitamin A intake (95% CI, 0.10-0.80; P < .033) and disease conditions (95% CI, 0.10-0.79; P = .006) through weighted UniFrac distances. The candidate pathogen associated with the disease groups were identified through analysis of the composition of microbiomes analysis. CONCLUSIONS: This study provides preliminary evidence for the fecal microbiome-derived dysbiosis signature and pathobiome concept that may be observed in young children during illness.

Infectious disease symptoms and microbial carriage among French medical students travelling abroad: A prospective study.

BACKGROUND: In France, no previous studies have focused specifically on health problems among medical students during internships abroad including the clinical symptoms suggestive of infectious diseases and the acquisition of pathogen carriage. METHODS: Clinical follow up and qPCR based respiratory, gastrointestinal and vaginal pathogen carriage before and after travel were prospectively assessed in a cohort of medical students departing from Marseille, France. RESULTS: 134 students were included. 73.9%, 38.8% and 5.0% of students reported gastrointestinal, respiratory and vaginal symptoms, respectively. The acquisition rate of Enteroaggregative Escherichia coli (EAEC) and Enteropathogenic E. coli (EPEC) was 53% and 41%, respectively. The acquisition of respiratory viruses was low but associated with persisting symptoms, while bacterial acquisition ranged from 3.3% for Streptococcus pyogenes to 15.0% for Haemophilus influenzae. Gardnerella vaginalis and Atopobium vaginae acquisition rates were 7.7% and 14.3% respectively. Five students (5.1%) had molecular quantification criteria for bacterial vaginosis on return. CONCLUSION: This preliminary study demonstrates that besides the known risk of gastrointestinal and respiratory infections and associated changes in intestinal and respiratory microbiota, medical students abroad may also experience changes in vaginal microbiota leading, in some cases, to clinical symptoms or the acquisition of bacterial vaginosis, which may be asymptomatic.

The impact of small intestinal bacterial overgrowth on the growth of children and adolescents / Impacto do sobrecrescimento bacteriano no intestino delgado sobre o peso e a estatura de crianças e adolescentes

ABSTRACT Objective: To evaluate the association between small intestinal bacterial overgrowth (SIBO) and weight and height impairment in children and adolescents with gastroenterology diseases. Methods: Observational and retrospective study. All 162 patients aged less than 19 years old who underwent breath test in search of SIBO between 2011 and 2016 were studied. Breath test was collected after the intake of 10 grams of lactulose. The concentration of hydrogen and methane was measured for 180 minutes after the beginning of the test by 12i QuinTronMicroLyzer device. Results: SIBO was identified in 51 (31.5%) patients. There was no difference between the age of those with (mean=8.7y.o; 25th and 75th percentile: 4.6 and 11.3) and without (mean=7.9y.o 25th and 75th percentile: 4.8 and 12.2) SIBO (p=0.910). There was no association between gender and SIBO (male 26.3% vs. female 36.3%, p=1.00). A lower median of height-for-age Z score (mean=-1.32; 25th and 75th percentile: -2.12 and -0.08 vs. mean=-0.59; 25th and 75th percentile: -1.57 and 0.22; p=0.04) was demonstrated in children with SIBO when compared with children without it. There was no difference between the BMI-for-age Z score of patients with (mean=-0.48) and without SIBO (mean=-0.06) (p=0.106). The BMI of patients with SIBO (median=15.39) was lower than of those without it (median=16.06); however, the statistical analysis was not significant (p=0.052). The weight-for-age Z score was lower in patients with SIBO (mean=-0.96) than in those without SIBO (mean=-0.22) (p=0.02) Conclusions: Children and adolescents with SBIO associated with diseases of the gastrointestinal tract have lower weight and height values.

RESUMO Objetivo: Avaliar a existência de associação entre sobrecrescimento bacteriano no intestino delgado (SBID) e comprometimento de peso e estatura em crianças e adolescentes com doenças do aparelho digestivo. Métodos: Estudo observacional e retrospectivo em ambulatório de gastroenterologia pediátrica. Foram incluídos todos os 162 pacientes com idade inferior a 19 anos que realizaram teste respiratório para pesquisa de SBID entre 2011 e 2016. O teste respiratório foi realizado após ingestão de dez gramas de lactulose. Foram determinadas as concentrações de hidrogênio e metano em aparelho 12i QuinTron MicroLyzer até 180 minutos após o início do teste respiratório. Resultados: SBID foi caracterizado em 51 (31,5%) dos 162 pacientes. Não houve diferença na idade das crianças com (mediana=8,7 anos; percentil 25-75: 4,6-11,3) e sem (mediana=7,9 anos; percentil 25-75: 4,8-12,2) SBID (p=0,910). Não se observou associação entre SBID e sexo (masculino 27,4% e feminino 36,6%; p=0,283). O escore Z da estatura-idade nos pacientes com SBID (mediana=-1,32; percentil 25-75: -2,12—0,08) foi menor (p=0,040) do que naqueles sem SBID (mediana=-0,59; percentil 25-75: -1,57-0,22). Na comparação do escore Z de índice de massa corpórea-idade não foi observada diferença entre os grupos com (média=-0,489±1,528) e sem (média=-0,067±1,532) SBID (p=0,106). Nos pacientes com menos de 10 anos de idade, o escore Z de peso-idade foi menor nos pacientes com SBID (média=-0,968±1,359) do que nos sem SBID (média=-0,223±1,584) (p=0,026). Conclusões: Crianças e adolescentes com SBID associado a doenças do trato gastrintestinal apresentam menores valores de peso e estatura.

Effect of probiotics on gastrointestinal symptoms and immune parameters in systemic sclerosis: a randomized placebo-controlled trial.

OBJECTIVES: Changes in the intestinal microbiota have been associated with the pathogenesis of SSc. Probiotics act by modulating the microbiome and the immune response. This study aimed to evaluate the efficacy of probiotics on gastrointestinal (GI) symptoms and immune responses in SSc patients. METHODS: Patients with SSc with a moderate-severe total score on the University of California Los Angeles Scleroderma Clinical Trials Consortium Gastrointestinal Tract 2.0 (UCLA GIT 2.0) instrument were randomly assigned to receive a daily dose of probiotics (Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus acidophillus and Bifidobacterium lactis, 109 colony-forming units per capsule) or placebo for 8 weeks. The primary endpoint was improvement in the UCLA GIT 2.0 total score after 8 weeks. Secondary outcomes included changes in Th1, Th2, Th17 and regulatory T cell circulating levels and in the HAQ Disability Index (HAQ-DI) score. Parameters were assessed at baseline and after 4 and 8 weeks of treatment. RESULTS: A total of 73 patients were randomized to receive probiotics (n = 37) or placebo (n = 36). After 8 weeks, there was no difference in the UCLA GIT 2.0 score between the two groups. At week 8, the probiotic group showed a significant decrease in the proportion of Th17 cells compared with placebo (P = 0.003). There was no difference in the proportion of Th1, Th2 and regulatory T cells or in the HAQ-DI score between the groups. CONCLUSION: Probiotics did not improve GI symptoms in SSc patients. The reduction in Th17 cell levels suggests an immunomodulatory effect of probiotics on SSc. TRIAL REGISTRATION: ClinicalTrials.gov (http://clinicaltrials.gov), NCT02302352.

Bowel symptoms in patients that receive proton pump inhibitors. Results of a multicenter survey in Mexico. / Síntomas intestinales en pacientes que reciben inhibidores de bomba de protones (IBP). Resultados de una encuesta multicéntrica en México.

INTRODUCTION: Proton pump inhibitors (PPIs) have been associated with small intestinal bacterial overgrowth (SIBO), which increases with prolonged PPI use, and SIBO has been associated with irritable bowel syndrome (IBS). OBJECTIVE: The aim of the present study was to study the prevalence of bowel symptoms in patients treated with PPIs in Mexico. METHODS: Gastroenterologists in 36 cities surveyed patients treated with PPIs, utilizing an ad hoc questionnaire to determine the presence of bowel symptoms and IBS. RESULTS: Two hundred and fifteen physicians interviewed 1,851 patients. PPI indications were gastritis (48.8%), gastroesophageal reflux (38.5%), peptic ulcer (6.2%), and others (6.5%). A total of 77.5% of the patients received treatment for ≤6 months and 11.9% for ≥1 year. Symptoms were reported in 92.3% of the patients: abnormal bowel habits (90%), bloating (82%), abdominal pain (63%), flatulence (58%), and abdominal discomfort (53%). A total of 67.5% of the patients fit the Rome III criteria for IBS. Symptoms presented in 55.9% of the patients before PPI intake and in 44.1% of the patients after PPI use (P<.005). Constipation (63.8%) predominated in the former, and diarrhea (56.5%) in the latter (P<.0001). The treatments prescribed for managing those symptoms were antispasmodics, antibiotics, prokinetics, and antiflatulents, but patients stated greater satisfaction with antibiotics (mainly rifaximin) (P<.0001). CONCLUSION: The association of PPIs with bowel symptoms and IBS is frequent in Mexico. Diarrhea and bloating predominate, and antibiotics produce the greatest treatment satisfaction, suggesting that SIBO or dysbiosis is the cause of the PPI-related bowel symptoms. However, that remains to be confirmed.

Potential interactions among phenolic compounds and probiotics for mutual boosting of their health-promoting properties and food functionalities - A review.

Several foods are rich sources of phenolic compounds (PC) and their beneficial effects on human health may be increased through the action of probiotics. Additionally, probiotics may use PC as substrates, increasing their survival and functionality. This review presents available studies on the effects of PC on probiotics, including their physiological functionalities, interactions and capability of surviving during exposure to gastrointestinal conditions and when incorporated into food matrices. Studies have shown that PC can improve the adhesion capacity and survival of probiotics during exposure to conditions that mimic the gastrointestinal tract. There is strong evidence that PC can modulate the composition of the gut microbiota in hosts, improving a variety of biochemical markers and risk factors for chronic diseases. Available literature also indicates that metabolites of PC formed by intestinal microorganisms, including probiotics, exert a variety of benefits on host health. These metabolites are typically more active than parental dietary PC. The presence of PC commonly enhances probiotic survival in different foods. Finally, further clinical studies need to be developed to confirm in vitro and experimental findings concerning the beneficial interactions among different PC and probiotics.

[Helicobacter pylori infection detected during upper gastrointestinal endoscopy]. / Disminución en la frecuencia de infección por Helicobacter pylori en endoscopías digestivas altas.

BACKGROUND: Helicobacter pylori (HP) is the most widespread chronic human infection worldwide and the most important pathogenic factor of gastric cancer. The calculated prevalence at the Clinical Hospital of the University of Chile from 2002 to 2005 was 44.9%. AIM: To determine the current prevalence of HP in patients undergoing an upper gastrointestinal endoscopy (UGI) and analyze its distribution according to age and endoscopic findings. MATERIAL AND METHODS: We reviewed 3.433 UGI performed during the year 2015, selecting those in which rapid urease test (RUT) was done. A positive RUT or a positive gastric biopsy (GB) were considered as HP infection. RESULTS: RUT was done in 1862 UGI (55%) performed in patients aged 51 ± 17 years, (66% women). In 23% of these endoscopies, the RUT was positive. A GB was obtained 43% of endoscopies and 30% were positive for HP. In 105 patients the RUT was negative and the GB positive (rendering a 19.5% false negative rate). HP was detected by RUT and GB in 29% of endoscopies. The highest prevalence of infection (38.1%) was found between 40 and 49 years. HP infection had odds ratio of 4.24 for nodular gastropathy, 2.63 for gastric ulcer and 2.14 for duodenal ulcer (p < 0.05). CONCLUSIONS: HP prevalence in our center decreased significantly from 44.9% to 28.9% in 11 years. False negative RUT results may bias this finding. The use of proton pump inhibitors and antimicrobials that can interfere with the detection of HP should be registered to properly analyze the results of the RUT.

First characterization of a microsporidial triosephosphate isomerase and the biochemical mechanisms of its inactivation to propose a new druggable target.

The microsporidia are a large group of intracellular parasites with a broad range of hosts, including humans. Encephalitozoon intestinalis is the second microsporidia species most frequently associated with gastrointestinal disease in humans, especially immunocompromised or immunosuppressed individuals, including children and the elderly. The prevalence reported worldwide in these groups ranges from 0 to 60%. Currently, albendazole is most commonly used to treat microsporidiosis caused by Encephalitozoon species. However, the results of treatment are variable, and relapse can occur. Consequently, efforts are being directed toward identifying more effective drugs for treating microsporidiosis, and the study of new molecular targets appears promising. These parasites lack mitochondria, and oxidative phosphorylation therefore does not occur, which suggests the enzymes involved in glycolysis as potential drug targets. Here, we have for the first time characterized the glycolytic enzyme triosephosphate isomerase of E. intestinalis at the functional and structural levels. Our results demonstrate the mechanisms of inactivation of this enzyme by thiol-reactive compounds. The most striking result of this study is the demonstration that established safe drugs such as omeprazole, rabeprazole and sulbutiamine can effectively inactivate this microsporidial enzyme and might be considered as potential drugs for treating this important disease.

Disminución en la frecuencia de infección por Helicobacter pylori en endoscopías digestivas altas / Helicobacter pylori infection detected during upper gastrointestinal endoscopy

Background: Helicobacter pylori (HP) is the most widespread chronic human infection worldwide and the most important pathogenic factor of gastric cancer. The calculated prevalence at the Clinical Hospital of the University of Chile from 2002 to 2005 was 44.9%. Aim: To determine the current prevalence of HP in patients undergoing an upper gastrointestinal endoscopy (UGI) and analyze its distribution according to age and endoscopic findings. Material and Methods: We reviewed 3.433 UGI performed during the year 2015, selecting those in which rapid urease test (RUT) was done. A positive RUT or a positive gastric biopsy (GB) were considered as HP infection. Results: RUT was done in 1862 UGI (55%) performed in patients aged 51 ± 17 years, (66% women). In 23% of these endoscopies, the RUT was positive. A GB was obtained 43% of endoscopies and 30% were positive for HP. In 105 patients the RUT was negative and the GB positive (rendering a 19.5% false negative rate). HP was detected by RUT and GB in 29% of endoscopies. The highest prevalence of infection (38.1%) was found between 40 and 49 years. HP infection had odds ratio of 4.24 for nodular gastropathy, 2.63 for gastric ulcer and 2.14 for duodenal ulcer (p < 0.05). Conclusions: HP prevalence in our center decreased significantly from 44.9% to 28.9% in 11 years. False negative RUT results may bias this finding. The use of proton pump inhibitors and antimicrobials that can interfere with the detection of HP should be registered to properly analyze the results of the RUT.

Functional gastrointestinal disorders in children from low socio-economic status and Helicobacter pylori infection.

BACKGROUND: Most studies on functional gastrointestinal disorders (FGIDs) in children are based on data from the northern hemisphere. Scientific reports are arising in South American population, but little is still known about children from low socio-economic status (SES), where Helicobacter pylori infection is endemic. Our objective was to evaluate the prevalence of FGIDs in school children from low SES and its relationship with H. pylori infection. METHODS: Children from 3 public schools of low SES from Santiago de Chile were included. Students completed the Rome III Questionnaire and a survey about other symptoms. Also, the 13 C urea breath test determined the presence of H. pylori infection. RESULTS: Five hundred six children were included, where 48% were male, with a median age of 15.7 years (range 7.1-19.6). Forty-two percent had some FGID, aerophagia and functional constipation being the most frequent. Females (adjusted OR 1.5, 95% CI [1.1, 2.2]), those children with parents within the lowest level of education (adjusted OR 1.6, 95% CI: 1.1-2.4), and family history of gastric cancer (adjusted OR 1.9, 95% CI: 1.2-3.1) were related to FGIDs. The prevalence of H. pylori infection was 55.9% (95% CI [50.7, 60.9]). In multivariable analysis, the presence of abdominal pain (OR 1.55, 95% CI [1.02, 2.36]), but not FGIDs, was related to H. pylori infection. CONCLUSIONS: FGIDs are common in low SES students. A low educational level of the household head, family history of gastric cancer. and being female are related to the development of FGIDs. In this study, no relationship between the presence of H. pylori and FGIDs was found.

Genomic and clinical evidence uncovers the enterohepatic species Helicobacter valdiviensis as a potential human intestinal pathogen.

BACKGROUND: Helicobacter valdiviensis is a recently described enterohepatic species isolated from wild bird's fecal samples. Currently, its pathogenic potential and clinical significance are unknown mainly due to the lack of whole-genome sequences to compare with other helicobacters and the absence of specific screenings to determine its prevalence in humans. MATERIALS AND METHODS: The species type strain (WBE14T ) was whole-genome-sequenced, and comparative analyses were carried out including the genomes from other Helicobacter species to determine the exact phylogenetic position of H. valdiviensis and to study the presence and evolution of virulence determinants. In parallel, stools from diarrheic patients and healthy individuals were screened by PCR to assess the clinical incidence of H. valdiviensis. RESULTS: Helicobacter valdiviensis belongs to a monophyletic clade conformed by H. canadensis, H. pullorum, H. winghamensis, H. rodentium, and H. apodemus. Its predicted genome size is 2 176 246 bp., with 30% of G+C content and 2064 annotated protein-coding genes. The patterns of virulence factors in H. valdiviensis were similar to other enterohepatic species, but evidence of horizontal gene transfer from Campylobacter species was detected for key genes like those coding for the CDT subunits. Positive PCR results confirmed the presence of H. valdiviensis in 2 of 254 (0.78%) stools of patients with acute diarrhea while not a single sample was positive in healthy individuals. CONCLUSIONS: Horizontal gene transfer has contributed to shape the gene repertory of H. valdiviensis, which codes for virulence factors conserved in other pathogens that are well-known human pathogens. Additionally, the detection of H. valdiviensisDNA in diarrheic patients supports its role as a potential emergent intestinal pathogen. Further, sampling efforts are needed to uncover the clinical relevance of this species, which should be accomplished by the isolation of H. valdiviensis from ill humans and the obtention of whole genomes from clinical isolates.