Irritable bowel syndrome (IBS) is a gastrointestinal disease characterized by altered intestinal motility, affecting about 11% of the world’s population. The prevalence of IBS among different countries varies such as in Pakistan it is 13.34%, Iran 7.13%, China 11.5%, United States of America 20.4%, United Kingdom 21.65% and in Japan 14.04%. This variation in the prevalence of this most common functional disorder is attributed to the wide clinical spectrum and the different criteria used for the diagnosis of this disorder.
IBS patients usually present with a complex of symptoms which is difficult to treat. These symptoms have a negative impact on the patient’s value of life. The patients suffer from severe depression with tendency of suicide. Treating patients usually involves surgeries and invasive measures [4, 5] .The efficacy of the up-to-date treatment modalities for IBS is low mainly because of the heterogeneous nature of the disease pathophysiology includes hypersensitive viscera’s, altered gut motility, distorted interactions of brain with gut, intolerance to specific foods, altered intestinal permeability and inflammatory changes in the gut. More recently the role of enteric infections and intestinal inflammation along with the implications of changing gut flora has been proposed in the pathogenesis of IBS. Based on these facts it was suggested that the IBS patients may have bacterial overgrowth and the eradication or altering the gut flora may improve symptoms in these subset of patients[8, 9].
To improve immunize the patients against environmental opportunistic, probiotics are used. These probiotics are usually live or attenuated bacteria or bacterial metabolites . How probiotics improves the symptoms of IBS patients is still to be understood, but few concepts have been postulated with evidences. As enteric flora is thought to play some role in the disease pathogenesis, gut functions improves with changes in gut flora attributed to probiotics. In post-infectious IBS the disease course is altered by the antibacterial and antiviral effects possessed by many probiotic organisms. Anti-inflammatory actions of probiotics on the gut’s mucosal surface may decrease the firing of enteric neurons, mediated by the immune system, resulting in lesser stimulus and response cycles between the gut’s mucosa and brain. The probiotics are considered to play a role in transforming short chain fatty acids from the undigested carbohydrates, which in turn have its influence on intestinal handling of its contents by acting as nutrients for the enteric cells.
Lactobacillus plantarum 299v (L. plantarum 299v) is the most widely studied strain in the IBS patients. It is resistant to the actions of intestinal acids and bile, colonizes the human colonic mucosa and is non-pathogenic in nature. While adhere to the colonic mucosal layer it reduces the inflammation by its antimicrobial activity against many potential pathogens importantly gram negative bacteria which contains endotoxins. The synthesis and seceretion of the interleukin-10 from the macrophages and the T-cells of the inflamed colon is increased by the L.Plantarum which has got beneficial immnuomodulatory activity. The lowering of the colonic pH by small chain fatty acids helps in controlling the growth of the microbes in the gut, L.Plantarum increases the concentration of carboxylic, acetic and propionic acids in the feces.
The results from the previous international trails were very encouraging regarding the safety and the efficacy of the probiotics use in IBS. The aim of the present study was to assess the efficacy L. Plantarum 299v against in local population suffering from IBS with improved study design and larger sample size.