Biotherapeutic agents. A neglected modality for the treatment and prevention of selected intestinal and vaginal infections.

To evaluate the potential of biotherapeutic agents (microorganisms with therapeutic properties) for the prevention and/or treatment of selected intestinal and vaginal infections. The MEDLINE database was searched for all relevant articles published between 1966 and September 1995. Search terms used were biotherapeutic agent, probiotic, Lactobacillus, Saccharomyces, Bifidobacterium, Candida, gastrointestinal- system, vaginitis, vaginosis-bacterial, and related terms. The bibliographies of obtained articles were also reviewed. All placebo-controlled human studies on biotherapeutic agents were reviewed. English-language open trials, case series and reports, and animal studies were reviewed only if they were especially relevant to providing information on the potential efficacy, adverse effects, or mechanisms of action of these agents. Placebo-controlled studies have shown that biotherapeutic agents have been used successfully to prevent antibiotic-associated diarrhea (Lactobacillus caseiGG, bifidobacterium longum, B longum with L acidophilus, and Saccharomyces boulardii), to prevent acute infantile diarrhea (Bifidobacterium bifidum with Streptococcus thermophilus), to treat recurrent Clostridium difficile disease (S boulardii), and to treat various other diarrheal illnesses (Enterococcus faecium SF68, L caseiGG, and S boulardii). There is also evidence for Lactobacillus acidophilus in the prevention of candidal vaginitis. Few adverse effects have been reported. However, many of the studies tested only small numbers of patients or volunteers. There is now evidence that administration of selected microorganisms is beneficial in the prevention and treatment of certain intestinal and, possibly, treatment of vaginal infections. In an effort to decrease the reliance on antimicrobials, the time has come to carefully explore the therapeutic applications of biotherapeutic agents.