Impact of imipenem resistance on mortality in patients with Acinetobacter bacteraemia

• Published in: Journal of antimicrobial chemotherapy 2007-03, Vol.59 (3), p.525-530
• Main Authors: Kwon, Ki Tae, Oh, Won Sup, Song, Jae-Hoon, Chang, Hyun-Ha, Jung, Sook-In, Kim, Shin-Woo, Ryu, Seong Yeol, Heo, Sang Taek, Jung, Dong Sik, Rhee, Ji-Young, Shin, Sang Yop, Ko, Kwan Soo, Peck, Kyong Ran, Lee, Nam Yong
• Format: Article
• Language: English
• Subjects: Acinetobacter; Acinetobacter Infections - drug therapy; Adult; Aged; Anti-Bacterial Agents - pharmacology; Antibiotics. Antiinfectious agents. Antiparasitic agents; attributable mortality; Bacteremia - drug therapy; Bacteremia - mortality; Bacteria; Bacterial diseases; Bacterial sepsis; Biological and medical sciences; Cohort Studies; discordant antimicrobial therapy; Drug resistance; Drug Resistance, Bacterial; Drug therapy; Female; Hospitals; Human bacterial diseases; Humans; Imipenem - pharmacology; Imipenem - therapeutic use; Infections; Infectious diseases; Male; matched cohort study; Medical sciences; Middle Aged; Mortality; Multivariate Analysis; Pharmacology. Drug treatments; Retrospective Studies
• ISSN: 0305-7453; 1460-2091
• DOI: 10.1093/jac/dkl499

Objectives To investigate the impact of imipenem resistance on the mortality rate among patients with Acinetobacter bacteraemia. Methods A retrospective, pairwise-matched (1:1), risk-adjusted (age, Pitt bacteraemia score) cohort study was performed at three tertiary care hospitals in Korea from January 2000 to June 2005. Results Forty patients with imipenem non-susceptible Acinetobacter bacteraemia (INAB group) and 40 matched subjects (1:1 ratio) with imipenem-susceptible Acinetobacter bacteraemia (ISAB group) were included. Both groups had similar clinical features related to the severity of illness. The 30 day mortality rate was higher in the INAB group (57.5%) than the ISAB group (27.5%) (P = 0.007). The rate of discordant antimicrobial therapy was higher in the INAB group (65.0%) than the ISAB group (20.0%) (P < 0.001). The 30 day mortality rate was higher in the patients with discordant antimicrobial therapy (67.6%) than concordant antimicrobial therapy (23.9%) (P < 0.001). Multivariate analysis showed that age, the Pitt bacteraemia score, immunosuppressive status, and discordant antimicrobial therapy were independent risk factors for 30 day mortality among patients with Acinetobacter bacteraemia (P < 0.05). When discordant antimicrobial therapy was excluded in the multivariate analysis, the imipenem resistance was associated with 30 day mortality (P = 0.005). Conclusions Imipenem resistance has a significant impact on the mortality rate among patients with Acinetobacter bacteraemia, and this is mainly attributable to the higher rate of discordant antimicrobial therapy.