Saturday, 14 October 2017

Klebsiella species share drug resistance genes


Three different species of Klebsiella bacteria can cause life-threatening infections in hospital patients and that all three share genes that confer resistance to the most commonly used antibiotics, new research shows. The study improves physicians' understanding of Klebsiella infections and could point toward better ways to fight multi-drug resistant strains of these bacteria.

The researchers sequenced the entire genome of 1,777 Klebsiella from clinical specimens across the greater Houston area. Until now, Klebsiella pneumoniae was thought to be the culprit in most serious Klebsiella infections. However, the research team noticed a group of 28 samples that looked genetically different.

Depending on the collection, between 2-12 percent of the samples had been misidentified as Klebsiella pneumoniae, and were in fact two related species, Klebsiella variicola or Klebsiella quasipneumoniae. K. variicola and K. quasipneumoniae had previously been characterized as commensal, nonpathogenic bacteria of the GI tract or agricultural pests, which rarely caused human infections. Long's team found they were capable of causing invasive and severe infections in patients, with the same rate of mortality as K. pneumoniae.

See:

S. Wesley Long, Randall J. Olsen, Todd N. Eagar, Stephen B. Beres, Picheng Zhao, James J. Davis, Thomas Brettin, Fangfang Xia, James M. Musser. Population Genomic Analysis of 1,777 Extended-Spectrum Beta-Lactamase-Producing Klebsiella pneumoniae Isolates, Houston, Texas: Unexpected Abundance of Clonal Group 307mBio, 2017; 8 (3): e00489-17 DOI: 10.1128/mBio.00489-17

Posted by Dr. Tim Sandle