Piperacillin/Tazobactam (TZP) and Escherichia coli, Morganella morganii, Proteus mirabilis, Proteus vulgaris, Providencia rettgeri, Providencia stuartii, Pseudomonas aeruginosa and Salmonella enterica Piperacillin/Tazobactam (TZP) and Klebsiella pneumoniae with resistant results
bioMérieux has provided instructions to its customers informing them that VITEK 2 susceptibility testing results for TZP for the organisms listed above are potentially inaccurate and should not be reported. An alternative method should be used for testing and reporting Piperacillin/Tazobactam susceptibility.
The previous product correction notification (410874) informed users that due to performance issues, users should test all E. coli strains (regardless of VITEK 2 results), and Klebsiella pneumoniae with resistance by VITEK 2 testing by an alternative method prior to reporting susceptibility results. A subsequent internal investigation conducted by bioMérieux determined that VITEK 2 Gram Negative Susceptibility cards may also incorrectly determine M. morganii, P. mirabilis, P. vulgaris, P. rettgeri, P. stuartii, P aeruginosa and S. enterica susceptibility such that susceptible isolates may be reported as resistant to Piperacillin/Tazobactam (TZP), and resistant isolates reported as susceptible to Piperacillin/Tazobactam (TZP). The current expanded recall is based on these findings. This investigation also confirmed the previously identified performance issues with E. coli and K. pneumoniae testing.
Incorrect results could potentially lead to patients being inappropriately treated with Piperacillin/Tazobactam when infected with a resistant E. coli, M. morganii, P. mirabilis, P. vulgaris, P. rettgeri, P. stuartii, P. aeruginosa or S. enterica isolate. There have been no reports to date of treatment failures associated with either falsely-resistant or falsely-susceptible results for Piperacillin/Tazobactam (TZP) and isolates of these specific organisms, or for falsely-resistant K. pneumoniae results.