The Role of Oral Probiotics in Alleviating Inflammation, Symptom Relief, and Postoperative Recurrence and Their Side Effects in Adults With Crohn's Disease: A Systematic Review

Crohn's disease (CD) is a lifelong problem for patients, despite having multiple pharmacological options and surgeries for treatment. In order to achieve best results, probiotics are being used even though their efficacy is still debatable. This systematic review analyzes the safety and efficacy of several probiotics in CD. PubMed, the Cochrane Library, and ScienceDirect are the databases searched for randomized controlled trials (RCTs), animal studies, in vitro studies, and reviews. After quality appraisal and cross checking the literature, this systematic review is carried out grounded on Preferred Reporting Items for Systematic Review and Meta-Analysis 2020 (PRISMA 2020) guidelines. A study of 16 papers in total which include nearly 2023 subjects showed that only very few probiotics are efficient in furnishing remission in CD complaints. Kefir, an inexpensive fermented milk product, significantly reduced the inflammation and drastically bettered the quality of life and hence can be considered as an asset for CD patients. Lactobacillus thermophilus, Bifidobacterium longum, Enterococcus faecalis, and Bacillus licheniformis can control diarrhea in patients of 22-54-year age group and improve cognitive reactivity in sad mood with short-term consumption. VSL#3 (VSL Pharmaceuticals, Gaithersburg, Maryland, United States) has good efficacy in precluding recurrence and easing side effects after ileocecal resection in adults. Animal models and lab studies have proved that Lactobacillus plantarum CBT LP3, Saccharomyces cerevisiae CNCM I-3856 (yeast), few strains of Lactobacillus plantarum, Bifidobacterium animalis spp., Lactobacillus acidophilus LA1, Lactobacillus paracasei 101/37, and especially Bifidobacterium breve Bbr8 are significant enough to ameliorate the disease condition. In conclusion, probiotics are safe in CD with very few modifiable side effects. Some probiotics are proven to be significant in animal and lab studies; hence, these should be studied in human RCTs, to check their efficiency in human beings. There are limited observational and interventional studies in this regard. Large population-sizes trials are highly demanded in the areas of prognosticated positive results that are mentioned in this systematic review.