Prolonged bacteraemia caused by VIM-1 metallo-beta-lactamase-producing Proteus mirabilis: first report from Italy

Persistent bacteraemia arising from a case of post-operative mediastinitis as a result of a Proteus mirabilis isolate, possessing two class 1 integrons carrying bla(VIM-1) and aadA2 gene cassettes located on chromosomal and plasmidic DNA, respectively, is reported. Despite the in vitro susceptibility to carbapenems, meropenem therapy failed, whereas the patient responded to treatment with cefepime plus amikacin. To our knowledge, this is the first report of metallo-beta-lactamase production in a clinical isolate of P. mirabilis in Italy.