Risk factors for developing clinical infection with carbapenem-resistant Klebsiella pneumoniae in hospital patients initially only colonized with carbapenem-resistant K pneumoniae

Background: This study examined predictors of carbapenem-resistant Klebsiella pneumoniae (CRKP) colonization and risk factors for the development of CRKP infection in patients initially only colonized with CRKP. Methods: A total of 464 patients with CRKP rectal colonization (CRKP-RC) were identified. Two case-control studies were performed, one comparing risk factors for CRKP-RC in patients who did not develop CRKP infection (CRKP-IN) versus patients without CRKP-RC and CRKP-IN, and the other comparing CRKP-RC patients who did not develop CRKP-IN with those who did. Results: Forty-two of the 464 colonized patients developed CRKP-IN. Multivariate analysis identified the following predictors for CRKP-RC: antibiotic therapy (odds ratio [OR], 5.76; P ≤.0001), aminopenicillin therapy (OR, 7.753; P =.004), bedridden (OR, 3.09; P =.021), and nursing home residency (OR, 3.09; P =.013). Risk factors for CRKP-IN in initially CRKP-RC-positive patients were previous invasive procedure (OR, 5.737; P =.021), diabetes mellitus (OR, 4.362; P =.017), solid tumor (OR, 3.422; P =.025), tracheostomy (OR, 4.978; P =.042), urinary catheter insertion (OR, 4.696; P =.037), and antipseudomonal penicillin (OR, 23.09; P ≤.0001). Conclusions: We suggest that in patients with CRKP-RC, a strategy for preventing CRKP-IN might include limiting antipseudomonal penicillin and carbapenem use and preventing infections by closely following compliance with infection control bundles.