Bacteremia caused by Acinetobacter junii at a medical center in Taiwan, 2000–2010

Abstract

We investigated the clinical characteristics and outcomes of 43 patients with Acinetobacter junii bacteremia at a 2,500-bed tertiary care center in northern Taiwan. These organisms were confirmed to the species level by an array assay and 16S rRNA gene sequence analysis. The antimicrobial susceptibilities of the 43 A. junii isolates to 13 agents were determined using the agar dilution method. Susceptibility testing for tigecycline was determined using the broth microdilution method. Most of the patients were hospital-acquired (n = 36, 83.7 %) or healthcare facility-related infections (n = 6, 13.9 %), and 55.8 % had impaired immunity. Central venous access devices were present in 35 (81.4 %) patients; among the total of 43 patients with A. junii bacteremia, 8 patients were diagnosed as catheter-related bloodstream infection and 19 patients were diagnosed as catheter-associated bloodstream infection. Shock requiring inotropic agents occurred in 2 patients (4.6 %). Most patients developed bacteremia in general wards (n = 36, 83.7 %). The overall in-hospital mortality rate was low (7 %), despite the low rate of removal of central venous devices, low rate of holding usage of original central venous devices, and high rate of inappropriate antimicrobial regimens. Carbapenems, fluoroquinolones, and amikacin had potent activity (>95 % susceptible rate) against A. junii isolates. Interestingly, 35 % of the A. junii isolates were resistant to colistin. Tigecycline exhibited low minimum inhibitory concentration (MIC) values (range, 0.06-2 μg/ml, MIC(90), 1 μg/ml) against the A. junii isolates.