Evaluation of a colorimetric test for the rapid detection of carbapenemase activity in Gram negative bacilli: the MAST® PAcE test.

The MAST Carba PAcE test is a colorimetric test used to detect carbapenemase-producing Gram-negative bacilli from cultured colonies. The performances of this test were compared to β-CARBA™, Carba NP test and RAPIDEC CARBA NP tests using a collection of 280 characterized isolates. Sensitivity and specificity of the MAST Carba PAcE test were 79.8% (95%IC: 73.3%-85.1%) and 98.9% (95%IC: 92.9%-99.9%). The MAST Carba PAcE sensitivity was the lowest mainly due to interpretation difficulties (particularly OXA-48-like).