Increased Relative Abundance of Klebsiella pneumoniae Carbapenemase-producing Klebsiella pneumoniae Within the Gut Microbiota Is Associated With Risk of Bloodstream Infection in Long-term Acute Care Hospital Patients

• Published in: Clinical infectious diseases 2019-05, Vol.68 (12), p.2053-2059
• Main Authors: Shimasaki, Teppei, Seekatz, Anna, Bassis, Christine, Rhee, Yoona, Yelin, Rachel D, Fogg, Louis, Dangana, Thelma, Cisneros, Enrique Cornejo, Weinstein, Robert A, Okamoto, Koh, Lolans, Karen, Schoeny, Michael, Lin, Michael Y, Moore, Nicholas M, Young, Vincent B, Hayden, Mary K
• Format: Article
• Language: English
• Subjects: Adult; Aged; and Commentaries; Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Bacteremia; Bacterial Proteins - biosynthesis; Bacterial Proteins - genetics; beta-Lactamases - biosynthesis; beta-Lactamases - genetics; Carbapenems - pharmacology; Carbapenems - therapeutic use; Cross Infection - epidemiology; Female; Gastrointestinal Microbiome; Hospitals; Humans; Klebsiella Infections - drug therapy; Klebsiella Infections - epidemiology; Klebsiella Infections - microbiology; Klebsiella pneumoniae - drug effects; Klebsiella pneumoniae - genetics; Longitudinal Studies; Male; Middle Aged; Proportional Hazards Models; ROC Curve
• ISSN: 1058-4838; 1537-6591
• DOI: 10.1093/cid/ciy796

Abstract Background An association between increased relative abundance of specific bacterial taxa in the intestinal microbiota and bacteremia has been reported in some high-risk patient populations. Methods We collected weekly rectal swab samples from patients at 1 long-term acute care hospital (LTACH) in Chicago from May 2015 to May 2016. Samples positive for Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) by polymerase chain reaction and culture underwent 16S rRNA gene sequence analysis; relative abundance of the operational taxonomic unit containing KPC-Kp was determined. Receiver operator characteristic (ROC) curves were constructed using results from the sample with highest relative abundance of KPC-Kp from each patient admission, excluding samples collected after KPC-Kp bacteremia. Cox regression analysis was performed to evaluate risk factors associated with time to achieve KPC-Kp relative abundance thresholds calculated by ROC curve analysis. Results We collected 2319 samples from 562 admissions (506 patients); KPC-Kp colonization was detected in 255 (45.4%) admissions and KPC-Kp bacteremia in 11 (4.3%). A relative abundance cutoff of 22% predicted KPC-Kp bacteremia with sensitivity 73%, specificity 72%, and relative risk 4.2 (P = .01). In a multivariable Cox regression model adjusted for age, Charlson comorbidity index, and medical devices, carbapenem receipt was associated with achieving the 22% relative abundance threshold (P = .044). Conclusion Carbapenem receipt was associated with increased hazard for high relative abundance of KPC-Kp in the gut microbiota. Increased relative abundance of KPC-Kp was associated with KPC-Kp bacteremia. Whether bacteremia arose directly from bacterial translocation or indirectly from skin contamination followed by bloodstream invasion remains to be determined. In adult long-term acute care hospital patients, carbapenem receipt was associated with increased hazard for high relative abundance of Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) in the gut microbiota. Increased relative abundance of KPC-Kp was associated with KPC-Kp bacteremia.