Thirty Years of Lactobacillus rhamnosus GG: A Review.

Lactobacillus rhamnosus GG (LGG) was the first strain belonging to the genus Lactobacillus to be patented in 1989 thanks to its ability to survive and to proliferate at gastric acid pH and in medium containing bile, and to adhere to enterocytes. Furthermore LGG is able to produces both a biofilm that can mechanically protect the mucosa, and different soluble factors beneficial to the gut by enhancing intestinal crypt survival, diminishing apoptosis of the intestinal epithelium, and preserving cytoskeletal integrity. Moreover LGG thanks to its lectin-like protein 1 and 2 inhibits some pathogens such as Salmonella species. Finally LGG is able to promote type 1 immune-responsiveness by reducing the expression of several activation and inflammation markers on monocytes and by increasing the production of interleukin-10, interleukin-12 and tumor necrosis factor-α in macrophages. A large number of research data on Lactobacillus GG is the basis for the use of this probiotic for human health. In this review we have considered predominantly randomized controlled trials, meta-analysis, Cochrane Review, guide lines of Scientific Societies and anyway studies whose results were evaluated by means of relative risk, odds ratio, weighted mean difference 95% confidence interval. The effectiveness of LGG in gastrointestinal infections and diarrhea, antibiotic and Clostridium difficile associated diarrhea, irritable bowel syndrome, inflammatory bowel disease, respiratory tract infections, allergy, cardiovascular diseases, nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, cystic fibrosis, cancer, elderly end sport were analyzed.

Probiotics and health: an evidence-based review.

The intestinal microbiota is an ecosystem formed by a variety of ecological niches, made of several bacterial species and a very large amount of strains. The microbiota is in close contact with the intestinal mucosa or epithelial interface which is, after the respiratory area, the largest surface of the body, occupying approximately 250-400 m(2). The physiological activities of the microbiota are manifold and are just being unraveled. Based on the observations of the multiple roles played by the microbiota in health and disease, the notion of modifying it with appropriate formulations, i.e. probiotics, is being tested in several settings. This review summarizes the current knowledge on probiotics and discusses both limitations and acquired evidence to support their use in preventive and therapeutic medicine.

["Probiotic medicine" and certainty of the evidence.] / "Probiotic medicine" e certezza delle evidenze.

These are excellent times for probiotic medicine. We have discovered more than 150,000 genomes of the microbiome, which can be aggregated into 4,930 species. However, the dream of microbiome-based medicine requires a new approach - an ecological and evolutionary understanding of host-microbe interactions, rather than a qualitative analysis of species. Yet researchers still disagree on what constitutes a healthy microbiome or how to define an altered one. There is still uncertainty as to which properties of the microbiome will represent the most informative biomarkers in clinical and epidemiological studies. And little is known about how the microbiomes of different regions of the body, such as the mouth, intestines or skin, interact. It is time to re-establish the foundations for the certainty of evidence in myocrobiome-based medicine. We believe robust new pillars are needed: starting clinical trials whenever possible; extending the role of N-of-1 trials; ending the "one probiotic for every disease" principle; reduce the number of outcomes of each research; search for the replicability of the results (the best test for the validity of an intervention with probiotics is not statistical significance but the replication of the result). Again, we would like to urge probiotic medicine researchers not to publish in "pirate" journals.

[Side effects of antibiotic: diarrhea and Clostridium difficile infection.] / Effetti collaterali degli antibiotici. Diarrea da antibotici e colite da Clostridium difficile.

Antibiotics are some of the most frequently prescribed medications worldwide, but antibiotic therapy may disturb the colonization resistance of gut microbiota to pathogenic bacteria, resulting in a range of symptoms that include, most notably, diarrhea that occurs between 7% and 33% of adults and 66 and 80% in pediatric patients (median of 22%) who take antibiotics. The diverse class of antibiotics may damage the metabolic homeostasis and can alter the level of intestinal metabolites including amino acids, bile acids, glucose, short chain fatty acids through alteration in abundance of metabolically active bacteria. Clostridium difficile is the main cause of antibiotics associated diarrhea: 3rd generation Cephalosporin, Clyndamicin, 2nd and 4th generation Cephalosporines, Sulfamethoxazole-trimethoprim, Quinolones, Penicillin combination show the strongest association with diarrhea.

[Clostridium difficile infection and chronic inflammatory bowel disease.] / Infezione da Clostridium difficile e malattie infiammatorie croniche intestinali.

Patients with IBD are at increased risk of developing Clostridium difficile (CD) infection and have worse outcomes, including higher rates of colectomy and death, and experience higher rates of recurrence. However, it is still not clear whether CD is a cause of IBD or a consequence of the inflammatory state and of intestinal dysbiosis. The association between IBD and CD may be due to different factors, such as drugs that are used for the treatment of IBD, including repeat courses of antibiotics, that might alter the intestinal flora and promote colonization, altered immune and nutritional status, frequent hospitalizations, and even genetic predisposition. It has been suggested that up to 20% of IBD flares were associated with testing positive for CD and retrospective studies demonstrated doubling of the infection incidence among patients with Crohn Disease, and a 3-fold increase among those with Ulcerative Colitis. They have also shown that the CD infection incidence among IBD patients is estimated as being 3-fold higher than that in the general population. Decreased intestinal microbial diversity along with an inadequate immune response is thought to play a causative role in the development of CD infection.

[Probiotics for the antibiotics associated diarrhea and for Clostridium difficile infection.] / Probiotici per la diarrea da antibiotici e per l'infezione da Clostridium difficile.

The term probiotic refers to live microorganisms that survive passage through the gastrointestinal tract and have beneficial effects on the host. Many strains of probiotic microorganisms have been shown to inhibit growth and metabolic activity as well as the adhesion to intestinal cells of enteropathogenic bacteria, to modulate the gut microbiota and to have immunostimulatory or regulatory properties. The use of probiotic microorganisms for the prevention and the treatment of Antibiotic Associated Diarrhea is an obvious measure and perhaps the most usual application of probiotics. This overview summarizes the most commonly used probiotic microorganisms for DAA and IBD.

Predicting mortality in non-variceal upper gastrointestinal bleeders: validation of the Italian PNED Score and Prospective Comparison with the Rockall Score.

OBJECTIVES: We sought (i) to validate a new prediction rule of mortality (Progetto Nazionale Emorragia Digestiva (PNED) score) on an independent population with non-variceal upper gastrointestinal bleeding (UGIB) and (ii) to compare the accuracy of the Italian PNED score vs. the Rockall score in predicting the risk of death. METHODS: We conducted prospective validation of analysis of consecutive patients with UGIB at 21 hospitals from 2007 to 2008. Outcome measure was 30-day mortality. All the variables used to calculate the Rockall score as well as those identified in the Italian predictive model were considered. Calibration of the model was tested using the chi2 goodness-of-fit and performance characteristics with receiver operating characteristic (ROC) analysis. The area under the ROC curve (AUC) was used to quantify the diagnostic accuracy of the two predictive models. RESULTS: Over a 16-month period, data on 1,360 patients were entered in a national database and analyzed. Peptic ulcer bleeding was recorded in 60.7% of cases. One or more comorbidities were present in 66% of patients. Endoscopic treatment was delivered in all high-risk patients followed by high-dose intravenous proton pump inhibitor in 95% of them. Sixty-six patients died (mortality 4.85%; 3.54-5.75). The PNED score showed a high discriminant capability and was significantly superior to the Rockall score in predicting the risk of death (AUC 0.81 (0.72-0.90) vs. 0.66 (0.60-0.72), P<0.000). Positive likelihood ratio for mortality in patients with a PNED risk score >8 was 16.05. CONCLUSIONS: The Italian 10-point score for the prediction of death was successfully validated in this independent population of patients with non-variceal gastrointestinal bleeding. The PNED score is accurate and superior to the Rockall score. Further external validation at the international level is needed.

Evaluation of the intestinal colonization by microencapsulated probiotic bacteria in comparison with the same uncoated strains.

BACKGROUND: Beneficial findings concerning probiotics are increasing day by day. However, one of the most important parameter which affects the probiotic activity of a microorganism is its survival during the gastroduodenal transit. Some microencapsulation techniques could be applied to bacterial cells to improve this parameter. METHODS: A comparison between the intestinal colonization by microencapsulated bacteria and the same not microencapsulated strains has been conducted in a double blind, randomized, cross-over study. The study (April to July 2005) involved 44 healthy volunteers. In particular, participants were divided into 2 groups: group A (21 participants) received a mix of probiotic strains Lactobacillus plantarum LP01 (LMG P-21021) and Bifidobacterium breve BR03 (DSM 16604) in an uncoated form, group B (23 participants) was given the same strains microencapsulated with a gastroresistant material. The not microencapsulated strains were administered at 5 x 10(9) colony forming units/strain/d for 21 days, whereas the microencapsulated bacteria were given at 1 x 10(9) colony forming units/strain/d for 21 days. At the end of the first period of treatment with probiotics a 3 weeks washout phase has been included in the study protocol. At the end of the washout period the groups were crossed: in detail, group A had the microencapsulated and group B the uncoated bacteria. The administered amounts of each strain were the same as the first treatment. The quantitative evaluation of intestinal colonization by strains microencapsulated or not microencapsulated was made by fecal samples examination at the beginning of the clinical trial, after 10 and 21 days of each treatment period. In particular, fecal heterofermentative Lactobacilli and Bifidobacteria have been counted. RESULTS: A statistically significant increase in the fecal amounts of Lactobacilli and Bifidobacteria was recorded in both groups at the end of each treatment compared with d0 or d42 (P<0.0001 and P<0.0001 at d21, P<0.0001 and P<0.0001 at d63 for Lactobacilli and Bifidobacteria, respectively), confirming the ability of the 2 strains to colonize the human gut, either in a gastroprotected form or not. Participants treated with the microencapsulated bacteria reported a kinetics of intestinal colonization quite similar to participants who received not coated strains. CONCLUSIONS: Probiotics are able to exert many different beneficial effects on the human host. These effects are mediated by the number of viable cells which reach the gut. The microencapsulation technique used in this study is a valid strategy to significantly improve gastroresistance of strains, thus enhancing their probiotic activity and allowing the use of a 5 times lower amount.

The use of probiotics in healthy volunteers with evacuation disorders and hard stools: a double-blind, randomized, placebo-controlled study.

BACKGROUND: Evacuation disorders and hard stools are common in industrialized countries, affecting on average 12% to 17% of the adult healthy population at any age. Dietary supplementation with probiotic microorganisms may be useful in reducing the disorder. METHODS: We performed a double-blind, randomized, placebo-controlled study to evaluate the effectiveness of 2 different probiotic blends, either mixed Lactobacillus plantarum LP01 (LMG P-21021) and Bifidobacterium breve BR03 (DSM 16604) or Bifidobacterium animalis subspecies lactis BS01 (LMG P-21384), in the management of evacuation disorders and intestinal discomfort. In a period of 5 years (2003 to 2008), the study involved 300 healthy volunteers (151 males and 149 females; age 24 to 71 y) with evacuation disorders and hard stools. In particular, subjects were divided into 3 groups: 80 subjects in the group A received placebo, 110 subjects in the group B received mixed L. plantarum LP01 and B. breve BR03 (2.5 x 10 colony-forming units/d of each strain), and 110 subjects in the group C received B. animalis subsp. lactis BS01 (5 x 10 colony-forming units/d) for 30 days. At the beginning of the observational study, the healthy status of volunteers was evaluated by a complete, laboratory and ultrasound study of the abdomen. The physical examination was repeated after 15 and 30 days. In particular, the main troubles typically associated with evacuation disorders and hard stools as well as abdominal bloating were considered as parameters of interest. Exclusion criteria were items of gastrointestinal diseases and antibiotics intake. RESULTS: Subjects treated with the mixed probiotic strains L. plantarum LP01 and B. breve BR03 or B. animalis subsp. lactis BS01 reported a significant improvement in the number of weekly bowel movements and in the main troubles associated with evacuations, particularly consistency of feces and ease of expulsion. Discomfort items such as abdominal bloating and anal itching, burning, or pain also registered a relevant improvement in the active groups receiving probiotics. CONCLUSIONS: The intake of an effective amount of mixed L. plantarum LP01 and B. breve BR03 or B. animalis subsp. lactis BS01 for 30 days is able to significantly relieve the evacuation disorders and hard stools, thus providing a useful tool for the management of such condition, which is particularly widespread in industrialized countries at any age.

Oral beclomethasone dipropionate as an alternative to systemic steroids in mild to moderate ulcerative colitis not responding to aminosalicylates.

BACKGROUND: Aminosalicylates (5-ASA) are first-line treatment for mild-moderate ulcerative colitis (UC). Systemic corticosteroids (CS) are considered for patients in whom 5-ASA has been unsuccessful, but their use is limited by adverse effects. Beclomethasone dipropionate (BDP), a topically acting steroid with low systemic bioavailability, has a more favorable safety profile, but its role in clinical practice is not yet well established. AIM: The aim of the present study is to assess whether oral BDP can be an alternative treatment to systemic CS for patients with mild-moderate UC not responding to first-line therapy with 5-ASA. METHODS: From 2003 to 2006, all consecutive patients with mild-moderate UC unresponsive to oral and topical 5-ASA (+/-topical CS) administered for at least 3 weeks received an 8-week course of oral BDP (10 mg/day for 4 weeks and 5 mg/day for an additional 4 weeks). Co-primary end-points were: (1) clinical remission within 8 weeks, without need of systemic CS; (2) steroid-free remission for 12 months. RESULTS: Sixty-four patients were included. In this study, within 8 weeks, 48/64 patients (75%) entered remission without systemic CS, while 16/64 (25%) failed to enter remission. Within 12 months, 37/64 patients (58%) had prolonged steroid-free remission, while 11/64 (17%) relapsed. During 1 year, 75% of patients receiving oral BDP could avoid systemic CS. CONCLUSIONS: Oral BDP can avoid the use of systemic CS in the vast majority of patients with mild-moderate UC not responding to 5-ASA and could be considered as a second-line treatment for these patients.

Predictive factors of mortality from nonvariceal upper gastrointestinal hemorrhage: a multicenter study.

OBJECTIVES: From an Italian Registry of patients with upper gastrointestinal hemorrhage (UGIH), we assessed the clinical outcomes and explored the roles of clinical, endoscopic, and therapeutic factors on 30-day mortality in a real life setting. METHODS: Prospective analysis of consecutive patients endoscoped for UGIH at 23 community and tertiary care institutions from 2003 to 2004. Covariates and outcomes were defined a priori and 30-day follow-up obtained. Logistic regression analysis identified predictors of mortality. RESULTS: One thousand and twenty patients were included. A total of 46 patients died for an overall 4.5% mortality rate. In all, 85% of deaths were associated with one or more major comorbidity. Sixteen of 46 patients (35%) died within the first 24 h of the onset of bleeding. Of these, eight had been categorized as ASA class 1 or 2 and none of them was operated upon, despite a failure of endoscopic intention to treatment in four. Regression analysis showed advanced age, presence of severe comorbidity, low hemoglobin levels at presentation, and worsening health status as the only independent predictors of 30-day mortality (P < 0.001). The acute use of a PPI exerted a protective effect (OR 0.23, 95% CI 0.09-0.73). Recurrent bleeding was low (3.2%). Rebleeders accounted for only 11% of the total patients deceased (OR 3.27, 95% CI 1.5-11.2). CONCLUSIONS: These results indicate that 30-day mortality for nonvariceal bleeding is low. Deaths occurred predominantly in elderly patients with severe comorbidities or those with failure of endoscopic intention to treatment.

In vitro sensitivity of probiotics to human pancreatic juice.

BACKGROUND: The resistance of gut flora with probiotic activity to pancreatic juice is usually tested with artificial pancreatic fluid. Previous studies evaluated the sensitivity of diverse probiotics to human gastric and biliary secretion; none tested the resistance of probiotics to human pancreatic juice. As most bacteria sensitive to artificial pancreatic fluid in vitro have a high rate of isolation from feces, the resistance to human pancreatic juice could be higher. AIM: The aim of this study was to compare the sensitivity of different strains of probiotics to artificial and human pancreatic juice. MATERIALS AND METHODS: The viability of 8 strains of Lactobacillus and 4 strains of Bifidobacterium was tested with standard artificial and human pancreatic juice withdrawn from 16 patients during endoscopic retrograde cholangiopancreatography procedure. The mortality rate (%) of various bacteria was measured after 5, 30, and 60 minutes contact time. The results were normalized for mortality rate induced by hypotonic condition and time exposure to 37 degrees C. RESULTS: When incubated with artificial and human pancreatic juice, the mortality rate of all strains of Lactobacillus at 5, 30, and 60 minutes was 10.1 versus 7.6, 20.5 versus 19.7, and 28.6 versus 29.8, respectively; whereas the mortality rate of all strains of Bifidobacterium was 8.0 versus 9.2, 33.3 versus 28.9, and 42.2 versus 44.4, respectively. CONCLUSIONS: All the tested strains were sensitive to artificial and human pancreatic juice depending on time contact. Bifidobacterium strains seem to be more sensitive than Lactobacillus strains in particular at higher time contact. There is no significant difference between sensitivity to simulated and human pancreatic juice. For this reason, probiotics activity may be tested with artificial pancreatic fluid using a standardized, easier, and less costly procedure.

[Evidence-based medicine vs personalized medicine.] / Evidence-based medicine vs medicina personalizzata.

Evidence-based medicine (EBM) and personalized medicine (PM) are driven by two diverse modes of reasoning about «evidence making¼. EBM has been criticized since his quality mark has been misappropriated by vested interests, the benefits statistically significant may be marginal in clinical practice, rigid rules and technology may produce care that is management driven rather than patient centered. On the contrary PM (or "precision medicine") refers to the tailoring of medical treatment to the specific characteristics of each patient involving the ability to classify individuals into subpopulations that are uniquely susceptible to a specific treatment, sparing expense and side effects and is derived from doubts on the results of subgroup analyses and on non responders in clinical trials typical of EBM. While both paradigms are epistemically sound they cannot, and should not, be hybridized into a unique model. Rather they ought to represent two compatible, but alternative ways of informing the Clinical practice. The clinicians may expect to see their responsibility increasing as they will deal with diverse, but equally compelling ways of reasoning and deciding about which intervention will qualify as the «best one¼ in each individual case.

[Revival of evidence-based medicine in gastroenterology.] / Per la rinascita della evidence-based medicine in gastroenterologia.

The evidence-based medicine (EBM) in gastroenterology is born with the XIII International Congress of Gastroenterology, the world congress of Gastroenterology, held in Rome in 1988. A clinical epidemiology manual was placed in the congress bag for each participant. The book contained an approach to biostatistics, interpretation of epidemiological data, clinical trials, meta-analysis and decision analysis. In the pocket appeared for the first time a floppy disk that offered softwares for the analysis of Student's and χ2, for randomization and for meta-analysis. In the following years the clinical epidemiology courses of Torgiano were born, now arriving at the 18th edition. The dedicated EBGH.it portal was also born. The reflections of recent years have suggested 8 theses for the renaissance of EBM in gastroenterology. 1. The patient must return to the center of the EBM. 2. There is an urgent need for more efficient production and implementation of evidences. 3. Researchers in gastroenterology should start studies only in relevant clinical fields where are not yet sufficient answers. 4. The EBM must move towards the evidence on the different effects of an intervention. 5. The relevance of the P-value should be reconsidered. 6. Precision medicine is growing. But EBM can not wait. 7. The best validity test is not the significance but the reproducibility of the data. 8. Data from the real world (real world evidence) can help increase the validity of clinical results.

[First part: the intestinal microbiota]. / Il microbiota intestinale.

The human gastrointestinal tract contains a large number of commensal (non pathogenic) and pathogenic microbial species that have co-evolved with the human genome and differ in composition and function based on their location, as well as age, sex, race/ethnicity, and diet of their host and we can in fact consider the human body as a mix of human and bacterial cells. It is now evident that the large intestine is much more than an organ for waste material and absorption of water, salts and drugs, and indeed has a very important impact on human health, for a major part related to the specific composition of the complex microbial community in the colon. In man, the large gut receives material from the ileum which has already been digested and the contents are then mixed and retained for 6-12 hours in the caecum and right colon. Thus, the large intestine is an open system, with nutrients flowing in the caecum, and bacteria, their metabolic products, and undigested foodstuffs being excreted as faeces. The anaerobic brakdown of carbohydrate and protein by bacteria is known conventionally as fermentation. In man the major end products are the short-chain fatty acids (SCFA) acetate, propionate, butirate, the gases H2 and CO2, ammonia, amines, phenols and energy, which the bacteria use for growth and the maintenance of cellular function. The microbiota is also an important factor in the development of the immune response. The interaction between the gastrointestinal tract and resident microbiota is well balanced in healthy individuals, but its breakdown can lead to intestinal and extraintestinal disease.