ORIGINAL ARTICLE Lactobacillus plantarum 299v Does Not Reduce Enteric Bacteria or Bacterial Translocation in Patients Undergoing Colon Resection Peter Mangell • Henrik Thorlacius • Ingvar Syk • Siv Ahrne ´ • Go ¨ran Molin • Crister Olsson • Bengt Jeppsson Received: 13 July 2011 / Accepted: 21 February 2012 / Published online: 21 March 2012 Ó Springer Science+Business Media, LLC 2012 Abstract Background Probiotics may exert beneficial effects in the gastrointestinal tract. This randomized trial investigated the effect of the probiotic Lactobacillus plantarum 299v on the intestinal load of potentially pathogenic bacteria, bac- terial translocation, and cell proliferation in elective colon surgery. Methods Seventy-five patients were randomized to pre- and postoperative oral intake of Lactobacillus plantarum 299v or placebo. Rectal swabs and mucosal biopsies were taken before the start of intake, after 1 week, at surgery, and after 6 days, weeks, and months. Viable counts were quantified for clostridia, Enterobacteriaceae, Gram- negative anaerobes, and lactobacilli. Bacterial translocation was determined by the analysis of bacterial DNA genes in mesenteric lymph nodes. Ki-67 was used as a marker of cell proliferation in normal mucosa and tumor. Results Lactobacillus plantarum 299v was given without adverse effects. Lactobacillus plantarum 299v as well as Enterobacteriaceae and Gram-negative anaerobes increased in the colon 1 week after the administration of Lactobacil- lus plantarum 299v. There were no significant differences between patients receiving Lactobacillus plantarum 299v and placebo in the incidence of bacterial translocation (27 vs. 13 %) and postoperative complications (16 vs. 31 %). Conclusions Lactobacillus plantarum 299v was estab- lished in the intestine, but no inhibitory effect on enteric bacteria, bacterial translocation, or postoperative compli- cations was found. The mechanism behind the protective effects of probiotics found in animal and some human studies remain elusive and require further explorations. No adverse effects were recorded after the administration of high doses of Lactobacillus plantarum 299v. Keywords Colon and rectal surgery Á Probiotics Á Lactobacillus plantarum Á Bacterial translocation Á Postoperative complications Introduction The intestinal microflora plays an important role in main- taining health, e.g., by supplying the intestinal mucosa with short chain fatty acids such as butyrate. However, the microflora also hosts potentially pathogenic bacteria, which may induce or perpetuate disease. To reduce this risk, P. Mangell (&) Á H. Thorlacius Á I. Syk Á C. Olsson Á B. Jeppsson Department of Clinical Sciences, Lund University, 205 02 Malmo ¨, Sweden e-mail: peter.mangell@med.lu.se H. Thorlacius e-mail: henrik.thorlacius@med.lu.se I. Syk e-mail: ingvar.syk@med.lu.se C. Olsson e-mail: crister.olsson@med.lu.se B. Jeppsson e-mail: bengt.jeppsson@med.lu.se P. Mangell Á H. Thorlacius Á I. Syk Á B. Jeppsson Department of Surgery, Skane University Hospital, 205 02 Malmo ¨, Sweden S. Ahrne ´ Á G. Molin Department of Food Technology, Engineering and Nutrition, Lund University, 221 00 Lund, Sweden e-mail: siv.ahrne@appliednutrition.lth.se G. Molin e-mail: goran.molin@appliednutrition.lth.se 123 Dig Dis Sci (2012) 57:1915–1924 DOI 10.1007/s10620-012-2102-y