Authors: Kajander K, Hatakka K, Poussa T, Farkkila M, Korpela R.

Institute: Valio Ltd, Research Centre, Helsinki, Finland.

Background: Irritable bowel syndrome is a gastrointestinal disorder of unknown aetiology. The effect of probiotics in this syndrome remains unclear. AIM: To investigate whether a probiotic mixture containing Lactobacillus rhamnosus GG, L. rhamnosus LC705, Bifidobacterium breve Bb99 and Propionibacterium freudenreichii ssp. shermanii JS is effective in alleviating irritable bowel syndrome symptoms.

Results: At the end the total symptom score (abdominal pain + distension + flatulence + borborygmi) was 7.7 (95% CI: -13.9 to -1.6) points lower in the probiotic group (P = 0.015). This represents a median reduction of 42% in the symptom score of the probiotic group compared with 6% in the placebo group. In individual symptoms, borborygmi was milder in the probiotic group (P = 0.008), and for the rest of the symptoms there was a non-significant trend.

Conclusions: The results indicate that this probiotic mixture is effective in alleviating irritable bowel syndrome symptoms. Considering the high prevalence of irritable bowel syndrome and the lack of effective therapies, even a slight reduction in symptoms could have positive public health consequences.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16128676&query_hl=76

Authors: Nobaek S, Johansson ML, Molin G, Ahrne S, Jeppsson B.

Institution: Department of Surgery, Lund University, Lund University Hospital, Sweden.

Objectives: The influence of the gastrointestinal (GI) microflora in patients with irritable bowel syndrome (IBS) has not been clearly elucidated. This study was undertaken to see if patients with IBS have an imbalance in their normal colonic flora, as some bacterial taxa are more prone to gas production than others. We also wanted to study whether the flora could be altered by exogenous supplementation.

Results: All patients tolerated the products well. The patients receiving Lb. plantarum had these bacteria on rectal biopsies. There were no major changes of Enterobacteriaceae in either group, before or after the study, but the Enterococci increased in the placebo group and remained unchanged in the test group. Flatulence was rapidly and significantly reduced in the test group compared with the placebo group (number of days with abundant gas production, test group 6.5 before, 3.1 after vs 7.4 before and 5.6 after for the placebo group). Abdominal pain was reduced in both groups. At the 12-month follow-up, patients in the test group maintained a better overall GI function than control patients.

Conclusions: The results of the study indicate that the administration of Lb. plantarum with known probiotic properties decreased pain and flatulence in patients with IBS. The fiber content of the test solution was minimal and it is unlikely that the fiber content could have had any effect. This type of probiotic therapy warrants further studies in IBS patients.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10811333&query_hl=74

Authors: O'Mahony L, McCarthy J, Kelly P, Hurley G, Luo F, Chen K, O'Sullivan GC, Kiely B, Collins JK, Shanahan F, Quigley EM.

Institution: Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.

Background and Aims: The aim of this study was to compare the response of symptoms and cytokine ratios in irritable bowel syndrome (IBS) with ingestion of probiotic preparations containing a lactobacillus or bifidobacterium strain.

Results: For all symptoms, with the exception of bowel movement frequency and consistency, those randomized to B infantis 35624 experienced a greater reduction in symptom scores; composite and individual scores for abdominal pain/discomfort, bloating/distention, and bowel movement difficulty were significantly lower than for placebo for those randomized to B infantis 35624 for most weeks of the treatment phase. At baseline, patients with IBS demonstrated an abnormal IL-10/IL-12 ratio, indicative of a proinflammatory, Th-1 state. This ratio was normalized by B infantis 35624 feeding alone.

Conclusions: B infantis 35624 alleviates symptoms in IBS; this symptomatic response was associated with normalization of the ratio of an anti-inflammatory to a proinflammatory cytokine, suggesting an immune-modulating role for this organism, in this disorder.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15765388&query_hl=70

Authors: Bazzocchi G, Gionchetti P, Almerigi PF, Amadini C, Campieri M.

Institution: Dept. of Internal Medicine and Gastroenterology, Bellana Hospital, University of Bologna, Italy. docbaz@alma.unibo.it

Summary: On the basis of many clinical and experimental observations, it would appear feasible to hold that the characteristics of the luminal milieu, the relationship, the balance between luminal prokaryotic cells and mucosal eukaryotic cells and the consequent immunological and humoral local and systemic responses take part in the pathophysiology of several diseases and, consequently bacteriotherapy can play a relevant role in the treatment and prevention of irritable bowel syndrome and more in general, of the intestinal functional disorders.

The irritable bowel syndrome is characterised by sudden and unforeseeable changes in the two main symptoms, constipation and diarrhoea, even within a few days. The amount and composition of proximal colon microflora, increasing with regard to the above-mentioned factors, and the time in which this development occurs, are, in our opinion, elements taking part, together with colon dysmotility and alterations of visceral perception, in the onset of the variability in stool frequency, typical of these patients.

The present open noncontrolled trial is the first observation showing a clinical improvement related to changes in the composition of the faecal bacterial flora and in faecal biochemistry and, remarkably, in the colonic motility pattern, all of which induced by administration of probiotics, in patients with functional diarrhoea.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12408440&query_hl=68