Comparison of a novel, rapid chromogenic biochemical assay, the Carba NP test, with the modified Hodge test for detection of carbapenemase-producing Gram-negative bacilli

Shawn Vasoo; Scott A Cunningham; Peggy C Kohner; Patricia J Simner; Jayawant N Mandrekar; Karen Lolans; Mary K Hayden; Robin Patel

doi:10.1128/JCM.00965-13

Comparison of a novel, rapid chromogenic biochemical assay, the Carba NP test, with the modified Hodge test for detection of carbapenemase-producing Gram-negative bacilli

J Clin Microbiol. 2013 Sep;51(9):3097-101. doi: 10.1128/JCM.00965-13. Epub 2013 Jul 3.

Authors

Shawn Vasoo¹, Scott A Cunningham, Peggy C Kohner, Patricia J Simner, Jayawant N Mandrekar, Karen Lolans, Mary K Hayden, Robin Patel

Affiliation

¹ Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA.

Abstract

We compared carbapenemase detection among 271 Gram-negative bacilli (of which 131 were carbapenemase producers) using a novel chromogenic rapid test--the Carba NP test (CNP)--and the modified Hodge test (MHT). Sensitivities were comparable (CNP, 100%, versus MHT, 98%; P = 0.08), but CNP was more specific (100% versus 80%; P < 0.0001) and faster.

MeSH terms

Bacterial Proteins / analysis*
Chromogenic Compounds / metabolism*
Colorimetry / methods*
Gram-Negative Bacteria / enzymology*
Humans
Sensitivity and Specificity
beta-Lactamases / analysis*

Substances

Bacterial Proteins
Chromogenic Compounds
beta-Lactamases
carbapenemase