Modulation of the intestinal ecosystem by probiotics and lactulose in children during treatment with ceftriaxone

Abstract

Background: The value of oral bacteriotherapy during antibiotic treatment is a much debated subject. Comparative studies on the effects of different probiotics on the intestinal ecosystem are lacking. Objective: Six different commercially available preparations of probiotics and 1 prebiotic (lactulose) were compared to establish whether their action prevented or corrected imbalances in the intestinal ecosystem (dysbiosis) during parenteral therapy with ceftriaxone. Methods: Fifty-one children (25 female, 26 male; mean age, 5.1 years) admitted to the hospital for febrile respiratory tract infections were treated. Ceftriaxone 50 mg/kg per day was administered parenterally alone (therapy 1) or with 1 of the following probiotic/prebiotic preparations: Saccharomyces boulardii (therapy 2); Enterococcus species (therapy 3); lactulose (therapy 4); Lactobacillus casei GG (therapy 5); Lactobacillus rhamnosus, Lactobacillus bifidus, and Lactobacillus acidophilus (therapy 6); Bifidobacterium bifidum and L acidophilus (therapy 7); or a mixture of various lactobacilli and bifidobacteria at high concentrations (therapy 8). Intestinal microflora were evaluated by standard microbiologic methods and by biochemical assays on fecal samples collected before and after treatment. Results: Ceftriaxone induced a decrease in Escherichia coli and lactobacilli counts and an increase in cocci and clostridia counts. Partial protection of the intestinal ecosystem (eubiosis) was achieved with therapies 6, 7, and 8, which contained different combinations of Lactobacillus and Bifidobacterium species. Probiotics containing lactobacilli were more active than the older Saccharomyces and Enterococcus preparations. The newer probiotics reduced β-galactosidase, β-glucosidase, and β-glucuronidase levels. Increased fecal β-lactamase activity was observed in 60% of patients treated with ceftriaxone alone and 75% of those treated with ceftriaxone and S boulardii. A lower incidence of beta-lactamase-positive samples (30%–40%) was observed with therapy 7 and therapy 8. Conclusions: In this preliminary study, probiotics containing multiple species of lactobacilli and bifidobacteria administered at high concentration (20 billion to 360 billion per day) were more effective in preventing dysbiosis induced by ceftriaxone treatment than were other preparations studied. Probiotic therapy may need to be maintained for several days after discontinuation of antibiotic treatment to adequately restore balance to the intestinal ecosystem.