Total intestinal decontamination for prevention of infection in bone marrow transplantation.

In an attempt to prevent infections complicating bone marrow transplantation, 22 patients received oral nonabsorbable antibiotics in protected environments. The standard antibiotic regimen consisted of gentamicin, vancomycin and nystatin. The vast majority of fecal organisms initially cultured were completely suppressed by about one week after initiation of antibiotic prophylaxis. The antibiotics had to be taken regularly to keep the gastrointestinal tract decontaminated. However, Candida was often cultured despite prophylaxis. The best method for continuously suppressing Candida was considered to be administering an adequate antifungal drug before intestinal decontamination. The throat, however, was far more difficult to decontaminate than the stool. Lincomycin inhalation was most effective in suppressing anaerobic bacteria. Some of the organisms cultured persistently or intermittently from the throat tended to appear sooner or later in the stool during prophylaxis, although they were not always resistant. The pattern of reappearance of the fecal flora after intestinal decontamination was similar to that observed in newborn infants. However, none of the Enterobacteriaceae strains which reappeared in the stool were identical to those cultured initially. Absorption of gentamicin and vancomycin from the gastrointestinal tract was negligible. A gentamicin-induced small-colony variant of Klebsiella pneumoniae was isolated from one patient. Amphotericin B was more tolerable than nystatin, which often produced nausea and vomiting in association with the preparative radio-chemotherapy for marrow transplantation. Hypoprothrombinemia and hypocholesterolemia were noted during prophylaxis. Three episodes of exogenous bacterial infection occurred despite strict isolation procedures.