Use of bacitracin therapy for infection due to vancomycin-resistant Enterococcus faecium.

An outbreak of infections due to vancomycin-resistant Enterococcusfaecium (VREF) was recently observed in a hospital in Southern California. Several patients developed fatal bacteremia or intraabdominal infection due to VREF. The gastrointestinal tract is the principal site of colonization of VREF, and prior colonization with resistant bacteria often preceded the development of life-threatening infection [1]. During the epidemic, several patients at the hospital and an adjacent long-term care facility had significant gastrointestinal colonization of VREF (determined with use of perirectal swabs). All the isolates were highly resistant to vancomycin (MIC, >32 j-tglmL), penicillin, gentamicin, and streptomycin but were susceptible to nitrofurantoin and bacitracin (at a level of < 16 j-tglmL). All of the colonized patients were placed in contact isolation [2]. We believed that oral bacitracin might be useful for eradicating VREF from the gastrointestinal tract in these colonized patients and that it might prevent life-threatening infection due to VREF. Eight patients who were colonized with VREF were treated with 25,000 units of bacitracin (no less than 50 units/mg, diluted in 5 mL of 0.9% normal saline); the antibiotic was given orally or by gastrostomy tube twice a day for 10 days, after which specimens for repeated cultures were obtained with use of perirectal swabs every week for 3 weeks. Perirectal swab specimens were screened for VREF by a method described previously [3]. All of the specimens had at least 2+ growth of VREF at the time of the initial stool screening. The results of perirectal swab cultures for five patients were repeatedly negative after one course of treatment with bacitracin, and one patient's cultures became negative only after a second course of treatment with this drug. Three ofthese six patients were subsequently treated with antibiotics for other infections, and one relapsed (the results of a perirectal culture were positive in this case). The results of perirectal cultures were persistently positive for two patients after they received therapy with bacitracin. Culture of specimens from the distal, anatomically disconnected rectum yielded VREF for one patient who underwent a diverting colostomy for a gangrenous colon even though VREF was eradicated from the colostomy drainage. The results of culture for one patient remained positive after one course of treatment with bacitracin, and this patient died of bacteremia due to VREF. All of the patients tolerated bacitracin therapy, without any side effects. The small, uncontrolled study reported herein suggests that use of oral bacitracin therapy may be a safe and effective way to