Comparison between bacteremia caused by Acinetobacter pittii and Acinetobacter nosocomialis

[[abstract]]AbstractBackground/Purpose Patients with Acinetobacter pittii and A. nosocomialis bacteraemia have lower mortality rates than those with A. baumannii bacteraemia. However, it is unknown whether these organisms differ in outcomes of bacteremic patients. We conducted this study to answer this question. Methods In this retrospective study conducted at a teaching hospital in Taiwan, we enrolled all 86 patients who had developed A. pittii bacteraemia and those with A. nosocomialis bacteraemia from 2000 to 2008 while matching for age, sex, APACHE II score, and appropriate antimicrobial therapy. After adjustment, we accessed the clinical characteristics and 14- and 28-day mortalities. Results We found that the patients with A. pittii bacteraemia had multiple comorbidities less often and received invasive procedures less frequently. The 14-day mortality rate of patients with A. pittii or A. nosocomialis bacteremia was 14% and 7%, respectively, whereas their 28-day mortality rate was 17% and 9%, respectively. Using the mortality rate in patients with A. nosocomialis bacteraemia as a reference, the odds ratios for the 14- and 28-day crude morality in those with A. pittii were 2.16 (95% confidence interval [CI], 0.77–6.05) and 2.06 (95% CI, 0.82–5.15), respectively, whereas the adjusted odds ratios for 14- and 28-day mortality were 1.89 (95% CI, 0.56–6.14) and 1.67 (95% CI, 0.59–4.78) respectively. Conclusions Our 8-year study showed the mortality rate of A. pittii bacteremia was higher but the difference was not statistically significant