Transmission of Carbapenem-resistant Klebsiella pneumoniae in US hospitals. 

 -  2022 
<br/><br/> BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKp) is the most prevalent carbapenem-resistant Enterobacterales in the United States. We evaluated clustering of CRKp in hospitalized patients in US hospitals.  CONCLUSIONS: Widespread intra-system and inter-system transmission of CRKp was identified in hospitalized US patients. Employing different methods for assessing genetic similarity resulted in only minor differences in interpretation. Copyright © The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.  METHODS: From April 2016 to August 2017, 350 patients with clonal group 258 were included as part of the Consortium on Resistance Against Carbapenems in Klebsiella and other Enterobacteriaceae (CRACKLE-2), a prospective, multicenter, cohort study. A maximum-likelihood tree was constructed using RAxML. Static clusters shared <=21 single nucleotide polymorphisms (SNP) and a most recent common ancestor. Dynamic clusters incorporated SNP distance, culture timing, and rates of SNP accumulation and transmission using the R program TransCluster.  RESULTS: Most patients were admitted from home (n = 150, 43%) or a long-term care facility (n = 115, 33%). Urine (n = 149, 43%) was the most common site of isolation. In total, 55 static and 47 dynamics clusters were identified involving 210/350 (60%) and 194/350 (55%) patients, respectively. About half of static clusters were identical to dynamic clusters. Static clusters consisted of 33 (60%) intra-system and 22 (40%) inter-system clusters. Dynamic clusters consisted of 32 (68%) intra-system and 15 (32%) inter-system clusters and had fewer SNP differences compared to static clusters (8 versus 9, P= 0.045, 95% CI: [-4, 0]). Dynamic inter-system clusters contained more patients than dynamic intra-system clusters (median [IQR]: 4 [2, 7] vs 2 [2, 2], P= 0.007, 95% CI: [-3, 0]). 
<br/><br/><br/>English 
<br/><br/><label>ISSN: </label>1058-4838 
<br/><br/><label>Standard No.: </label>10.1093/cid/ciac791 [doi] 6731222 [pii] 
<br/><br/><label>Subjects--Topical Terms: </label><br/>IN PROCESS -- NOT YET INDEXED
<br/><br/><label>Subjects--Geographic Terms: </label><br/>MedStar Washington Hospital Center
<br/><br/><label>Index Terms--Occupation: </label><br/>Medicine/Infectious Diseases
<br/><br/><label>Index Terms--Function: </label><br/>Journal Article