BACKGROUND: In the 1,200-bed university hospital "Umberto I" in Rome, Italy, we observed a dramatic substitution of a precedingly well-documented Klebsiella pneumoniae clone (ST37) with ertapenem resistance by outer membrane permeability modification (Porin-ER-Kp) with a new K. pneumoniae strain expressing carbapenem resistance due to K. pneumoniae carbapenemase production (KPC-CR-Kp). A case-case-control study was carried out to evaluate risk factors for Porin-ER-Kp and KPC-CR-Kp isolation. METHODS: All patients with hospital-acquired K. pneumoniae isolation between July 2008 and June 2011 were included. Two case groups including patients harbouring KPC-CR-Kp and Porin-ER-Kp were analysed, with a third control group from whom carbapenem-susceptible K. pneumoniae (CS-Kp) were isolated. RESULTS: Forty-four KPC-CR-Kp cases, 39 Porin-ER-Kp cases and 60 CS-Kp controls were analysed. During the 3-year study, a specific Porin-ER-Kp endemic clone (ST37) was substituted by a new KPC-CR-Kp clone (ST512). Breakthrough bacteraemias occurred in 21 out of 26 KPC-CR-Kp group bloodstream infections (BSIs); nine of these developed during carbapenem therapy and seven with colistin and/or tigecycline therapy. In 13 Porin-ER-Kp BSIs, breakthrough bacteraemias developed in eight patients and four during carbapenem therapy. In the multivariable analysis, KPC-CR-Kp isolates were associated with carbapenems [odds ratio (OR) 7.74; 95 % confidence interval (CI) 1.70-35.2; p < 0.01) and endoscopy (OR 6.71; 95 % CI 1.25-36.0; p < 0.03). Porin-ER-Kp independent risk factors included second-generation cephalosporins (OR 25.7; 95 % CI 3.20-206.8; p < 0.01), carbapenems (OR 19.1; 95 % CI 4.34-83.9; p < 0.001), acute renal failure (OR 7.17; 95 % CI 1.33-38.6; p < 0.03), endoscopy (OR 6.12; 95 % CI 1.46-25.6; p < 0.02) and third-generation cephalosporins (OR 5.3; 95 % CI 1.34-20.9; p < 0.02). CONCLUSIONS: Porin-ER-Kp strains needed major antimicrobial pressure compared to KPC-CR-Kp to express resistance. KPC-CR-Kp substituted Porin-ER-Kp strains, causing more infections. KPC-CR-Kp breakthrough bacteraemia occurred even under therapy with tigecycline or colistin, underlining that an antibiotic stewardship programme is needed urgently.
BACKGROUND: In the 1,200-bed university hospital "Umberto I" in Rome, Italy, we observed a dramatic substitution of a precedingly well-documented Klebsiella pneumoniae clone (ST37) with ertapenem resistance by outer membrane permeability modification (Porin-ER-Kp) with a new K. pneumoniae strain expressing carbapenem resistance due to K. pneumoniae carbapenemase production (KPC-CR-Kp). A case-case-control study was carried out to evaluate risk factors for Porin-ER-Kp and KPC-CR-Kp isolation. METHODS: All patients with hospital-acquired K. pneumoniae isolation between July 2008 and June 2011 were included. Two case groups including patients harbouring KPC-CR-Kp and Porin-ER-Kp were analysed, with a third control group from whom carbapenem-susceptible K. pneumoniae (CS-Kp) were isolated. RESULTS: Forty-four KPC-CR-Kp cases, 39 Porin-ER-Kp cases and 60 CS-Kp controls were analysed. During the 3-year study, a specific Porin-ER-Kp endemic clone (ST37) was substituted by a new KPC-CR-Kp clone (ST512). Breakthrough bacteraemias occurred in 21 out of 26 KPC-CR-Kp group bloodstream infections (BSIs); nine of these developed during carbapenem therapy and seven with colistin and/or tigecycline therapy. In 13 Porin-ER-Kp BSIs, breakthrough bacteraemias developed in eight patients and four during carbapenem therapy. In the multivariable analysis, KPC-CR-Kp isolates were associated with carbapenems [odds ratio (OR) 7.74; 95 % confidence interval (CI) 1.70-35.2; p < 0.01) and endoscopy (OR 6.71; 95 % CI 1.25-36.0; p < 0.03). Porin-ER-Kp independent risk factors included second-generation cephalosporins (OR 25.7; 95 % CI 3.20-206.8; p < 0.01), carbapenems (OR 19.1; 95 % CI 4.34-83.9; p < 0.001), acute renal failure (OR 7.17; 95 % CI 1.33-38.6; p < 0.03), endoscopy (OR 6.12; 95 % CI 1.46-25.6; p < 0.02) and third-generation cephalosporins (OR 5.3; 95 % CI 1.34-20.9; p < 0.02). CONCLUSIONS: Porin-ER-Kp strains needed major antimicrobial pressure compared to KPC-CR-Kp to express resistance. KPC-CR-Kp substituted Porin-ER-Kp strains, causing more infections. KPC-CR-Kp breakthrough bacteraemia occurred even under therapy with tigecycline or colistin, underlining that an antibiotic stewardship programme is needed urgently.
Authors: Ana Mena; Virginia Plasencia; Laura García; Olga Hidalgo; José Ignacio Ayestarán; Sebastián Alberti; Nuria Borrell; José L Pérez; Antonio Oliver Journal: J Clin Microbiol Date: 2006-08 Impact factor: 5.948
Authors: Leanne B Gasink; Paul H Edelstein; Ebbing Lautenbach; Marie Synnestvedt; Neil O Fishman Journal: Infect Control Hosp Epidemiol Date: 2009-12 Impact factor: 3.254
Authors: George L Daikos; Panayiotis Petrikkos; Mina Psichogiou; Chris Kosmidis; Evangelos Vryonis; Athanasios Skoutelis; Kleoniki Georgousi; Leonidas S Tzouvelekis; Panayotis T Tassios; Christina Bamia; George Petrikkos Journal: Antimicrob Agents Chemother Date: 2009-02-17 Impact factor: 5.191
Authors: Elizabeth B Nimmich; P Brandon Bookstaver; Joseph Kohn; Julie Ann Justo; Katie L Hammer; Helmut Albrecht; Majdi N Al-Hasan Journal: Hosp Pharm Date: 2017-07-21
Authors: Maristela P Freire; Edson Abdala; Maria L Moura; Flávio Jota de Paula; Fernanda Spadão; Hélio H Caiaffa-Filho; Elias David-Neto; William C Nahas; Ligia C Pierrotti Journal: Infection Date: 2015-02-18 Impact factor: 3.553
Authors: M P Freire; L C Pierrotti; H H C Filho; K Y Ibrahim; A S G K Magri; P R Bonazzi; L Hajar; M P E Diz; J Pereira; P M Hoff; E Abdala Journal: Eur J Clin Microbiol Infect Dis Date: 2014-08-30 Impact factor: 3.267