[Investigation of metallo-beta-lactamase-producing Acinetobacter sp and Pseudomonas aeruginosa at an emergency hospital in Porto Alegre, State of Rio Grande do Sul, Brazil].

Introduction: The appearance of metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa and Acinetobacter sp. is a challenge for hospitals.

Methods: The production of MBL in clinical isolates of Pseudomonas aeruginosa and Acinetobacter sp. From an emergency hospital in Porto Alegre was investigated using the disk approximation test and MBL E-test. The bla genes were determined using PCR.

Results: Two strains of Pseudomonas aeruginosa and eight of Acinetobacter sp were shown to be MBL phenotypes. Amplification of the blaSPM-1 gene confirmed the presence of the enzyme in P. aeruginosa.

Conclusions: Caution is needed in evaluating phenotype tests used for routine detection of metallo-beta-lactamases.