Dysbiosis is a clinical condition marked by altered gut microbiota resulting from external and internal host factors. It is strongly associated with gastrointestinal and extraintestinal alterations, so its symptomatology is broad and nonspecific. To date, gaps remain that limit professionals from making a timely diagnosis and prescribing the appropriate treatment. We aim to synthesize existing literature regarding clinical parameters for the early detection of patients with intestinal dysbiosis and the clinical events in which the use of probiotics as adjuvant therapy is most frequently reported. A scoping review of the literature was conducted in PubMed, Embase, Cochrane, and BVS (Biblioteca Virtual en Salud in Spanish) databases for articles published in the last 5 years. Primary studies and literature reviews related to clinical presentation, dysbiosis screening, and probiotics as adjuvant therapy for adult and pediatric patients were included. Twenty-three articles were retrieved in which the most frequently reported symptoms were abdominal distension, abdominal pain, and diarrhea. Chronic and metabolic diseases where the conditions most strongly associated with dysbiosis. Depending on symptomatology and etiology, dysbiosis is often treated with probiotics. Dysbiosis, often linked to diarrhea, should be considered with other symptoms like abdominal distension and pain, along with predisposing conditions and patient risk factors. Probiotics are commonly used as co-adjuvant treatments for antibiotic-associated diarrhea, irritable bowel syndrome, and childhood allergic diseases. The most commonly used probiotics were Weizmannia coagulans (formerly B. coagulans), Alkalihalobacillus clausii (formerly Bacillus clausii), Lacticaseibacillus rhamnosus, Limosilactobacillus reuteri, and Saccharomyces boulardii.

“Disorders of Gut-Brain Interaction (DGBIs),” formerly referred to as “Functional Gastrointestinal Disorders (FGIDs),” encompass a prevalent array of chronic or recurring gastrointestinal symptoms that notably impact the quality of life for affected children and their families. Recent studies have elucidated the intricate pathophysiology of DGBIs, underscoring their correlation with gut microbiota. This review seeks to explore the present comprehension of the gut microbiota's role in DGBI development. While other factors can contribute to DGBIs, the gut microbiota prominently influences the onset and progression of these conditions. According to the Rome IV diagnostic criteria, DGBI prevalence is approximately 40% worldwide. The Rome Foundation has diligently worked for nearly three decades to refine our comprehension of DGBIs. By centering on the gut microbiota, this review sheds light on potential therapeutic interventions for DGBIs, potentially enhancing the quality of life for pediatric patients and their families.

Background: Dysbiosis and antibiotic-associated diarrhea (AAD) are significant concerns in clinical settings. Probiotics, such as Bacillus clausii (O/C, N/R, SIN, T), a spore-forming bacterium resistant to gastrointestinal conditions and most commonly used antibiotics, emerge as a promising approach. We aim to assess the role of B. clausii in preventing AAD in children and adults during antibiotic therapy. Materials and methods: A systematic literature search was conducted across multiple databases, including MEDLINE, EMBASE, Cochrane Library, LILACS, and SciELO, up to May 2024. Studies were included if they involved B. clausii (O/C, N/R, SIN, T) administration during antibiotic treatment and reported AAD-related outcomes. Results: A total of four studies were included in the review. The studies comprised two randomized controlled trials (RCTs), one meta-analysis of RCTs, and one expert consensus. The primary outcome was the effectiveness of B. clausii (O/C, N/R, SIN, T) in reducing the incidence of diarrhea. Results showed a significant reduction in the risk of AAD and gastrointestinal symptoms in patients receiving it at a dosage of 4 × 10⁹ CFU/day for children and 6 × 10⁹ CFU/day for adolescents and adults for up to 14 days. Conclusions: B. clausii (O/C, N/R, SIN, T) appears to be an effective probiotic for preventing AAD in adults and children. It significantly improves gastrointestinal symptoms associated with antibiotic treatment, including diarrhea, nausea, and epigastric pain. Future studies are recommended to further elucidate its effectiveness in diverse populations, especially in low- and middle-income countries.

Introduction: Acute gastroenteritis (AGE) remains a major global clinical concern in pediatric populations. This systematic review and meta-analysis aimed to evaluate the efficacy and safety of Limosilactobacillus reuteri DSM 17938 for the treatment of acute gastroenteritis in children, with the duration of diarrhea as the primary outcome. Methods: A comprehensive literature search was conducted across MEDLINE (via PubMed), Embase, Scopus, and the Science Citation Index Expanded from inception to April 1, 2026. Two independent reviewers performed study selection, data extraction, and risk of bias assessment using the Cochrane RoB 2 tool. Random-effects models pooled mean differences (MD) and risk ratios (RR), and the certainty of the evidence was appraised via the GRADE approach. Results: Six randomized controlled trials involving 565 randomized children (527 analyzed for the primary outcome) met the inclusion criteria. Limosilactobacillus reuteri DSM 17938 significantly reduced the duration of diarrhea by a mean difference of 0.68 days (95% CI: -1.09 to -0.27). Furthermore, the persistence of diarrhea was significantly lower in the probiotic group at 48 hours (RR 0.45, 95% CI 0.29 to 0.69) and 72 hours (RR 0.41, 95% CI 0.23 to 0.72). No serious or treatment-related adverse events were reported across the trials. The certainty of the evidence was rated as very low for diarrhea duration and low for persistence at 48-72 hours due to high heterogeneity and risk of bias concerns. Discussion: Limosilactobacillus reuteri DSM 17938 produces a modest reduction in the duration of diarrhea and a substantial decrease in persistence at 48-72 hours, accompanied by a favorable safety profile. However, due to the very low certainty of the evidence regarding the primary outcome, these findings should be interpreted with caution in clinical practice. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD420261449562 , PROSPERO CRD420261449562.