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Rapid detection of <i>Klebsiella pneumoniae</i> carbapenemase (KPC) in the <i>Klebsiella</i> species is desirable. The MALDI Biotyper^® MBT Subtyping Module (Bruker Daltonics) uses an algorithm that detects a peak at ~11,109 m/z corresponding to a protein encoded by the <i>p019</i> gene to detect KPC simultaneously with organism identification by a matrix-assisted laser desorption ionization–time-of-flight mass spectrometry (MALDI-ToF MS). Here, the subtyping module was evaluated using 795 clinical <i>Klebsiella</i> isolates, with whole genome sequences used to assess for <i>bla</i>_KPC and <i>p019</i>. For the isolates identified as KPC positive by sequencing, the overall sensitivity of the MALDI-ToF MS subtyping module was 239/574 (42%) with 100% specificity. For the isolates harboring <i>p019</i>, the subtyping module showed a sensitivity of 97% (239/246) and a specificity of 100%. The subtyping module had poor sensitivity for the detection of <i>bla</i>_KPC-positive <i>Klebsiella</i> isolates, albeit exhibiting excellent specificity. The poor sensitivity was a result of <i>p019</i> being present in only 43% of the <i>bla</i>_KPC-positive <i>Klebsiella</i> isolates.