Phage therapy is an experimental therapeutic approach used to target multidrug-resistant
bacterial infections. A lack of reliable data with regard to its efficacy and regulatory hurdles hinders a broad application. Here we report, for the first time, a case of
vancomycin-resistant Enterococcus faecium abdominal
infection in a one-year-old,
critically ill, and three times liver transplanted girl, which was successfully treated with
intravenous injections (twice per day for 20 days) of a magistral preparation containing two Enterococcus phages. This correlated with a reduction in baseline
C-reactive protein (CRP), successful weaning from
mechanical ventilation and without associated clinical adverse events. Prior to clinical use, phage genome was sequenced to confirm the absence of genetic determinants conferring lysogeny, virulence or antibiotic resistance, and thus their safety. Using a phage neutralization assay, no neutralizing anti-phage
antibodies in the patient's serum could be detected.
Vancomycin-susceptible E. faecium isolates were identified in close relation to
phage therapy and, by using whole-genome sequencing, it was demonstrated that
vancomycin-susceptible E. faecium emerged from
vancomycin-resistant progenitors. Covering a one year follow up, we provide further evidence for the feasibility of
bacteriophage therapy that can serve as a basis for urgently needed controlled clinical trials.