Impact of imipenem resistance on mortality in patients with Acinetobacter bacteraemia.
OBJECTIVE
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.
Kwon
Ki Tae
KT
Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Seoul 135-710, Korea.
Oh
Won Sup
WS
Song
Jae-Hoon
JH
Chang
Hyun-Ha
HH
Jung
Sook-In
SI
Kim
Shin-Woo
SW
Ryu
Seong Yeol
SY
Heo
Sang Taek
ST
Jung
Dong Sik
DS
Rhee
Ji-Young
JY
Shin
Sang Yop
SY
Ko
Kwan Soo
KS
Peck
Kyong Ran
KR
Lee
Nam Yong
NY
D000151:Acinetobacter Infections / Q000188:drug therapy*; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000188:drug therapy* / Q000401:mortality; D015331:Cohort Studies; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D015378:Imipenem / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies
D000900:Anti-Bacterial Agents; D015378:Imipenem