ABSTRACT
OBJECTIVE: To evaluate the potential of probiotics or biotherapeutic agents for the prevention and/or treatment of selected intestinal infections. METHODS: Medline database was searched for all relevant articles between 1990 and February 1998. Bibliographies of articles were also used. All animal experiments and placebo-controlled human studies were reviewed in order to provide information on the mechanisms of action, potential efficacy, or adverse effects of these biotherapeutic agents. RESULTS: In the first part of this review, the different mechanisms of action that are effective in the treatment of diarrhea were discussed, and they were well demonstrated in laboratory animals. The most important are: enzymatic induction of disaccharidase activity, trophic effects on the intestinal mucosa, action in blocking bacterial toxins, and also induction of the immunologic response. Therapeutic effects of probiotics in humans, mainly in the gastrointestinal tract, were reported in the second part. Placebo-controlled studies have shown that biotherapeutic agents have been used successfully in the treatment of acute diarrhea in infants, traveler s diarrhea, antibiotic-associated diarrhea, with or without Clostridium difficile-associated enterocolitis (pseudomembranous colitis), and in immunosuppression-associated diarrhea, including AIDS. Lactobacillus, Bifidobacterium and Saccharomyces boulardii were the most important biotherapeutic agents to be considered. CONCLUSIONS: Currently, there is evidence that the administration of selected microorganisms is benefic in the prevention and treatment of certain intestinal infections. According to the literature, Saccharomyces boulardii is the most important probiotic. Possible future indications were discussed, such as the probable synergic effect of many probiotics due to their different and complementary mechanisms of action. The importance of new experimental and clinical studies for the better understanding of actions and the use of probiotics in other clinical situations was emphasized.
ABSTRACT
BACKGROUND: Constipation in childhood is a significant problem worldwide; however, understanding of its epidemiology is limited. Some investigators in the United States have estimated the prevalence of constipation to be 1.2% to 8.0% in the general population. In Brazil, some have found a prevalence of up to 36%. METHODS: This cross-sectional, descriptive, observational prevalence study included 391 pupils (age range, 8-10 years) who were attending three public education centers in Rio de Janeiro. The prevalence of constipation, associated symptoms, and dietary fiber intake were evaluated by questionnaire. A child was considered to be constipated when he or she reported difficulty in defecating two or more times per week. The children were divided into constipated and nonconstipated groups, and the presence of fecal soiling, blood in the feces, and shape of the feces were assessed. RESULTS: Twenty-eight percent of the children were constipated. There was no significant difference between the sexes. Blood in the stools was significantly more frequently reported by the constipated children (p < 0.01). There was no significant difference in the prevalence and frequency of fecal soiling or in the stool shape between the constipated and nonconstipated children (p > 0.1). Fiber content in the diet ranged from 3.4 to 4.8 g per day, which is below the range recommended. CONCLUSIONS: The prevalence of constipation in Rio de Janeiro is similar to the rates reported in all of Brazil and in a recent study from the United Kingdom but is much higher than that in the United States. In addition, the school menu was found to contain inadequate dietary fiber content.
