Şirin Menekşe1, Yasemin Çağ2, Mehmet Emirhan Işık3, Suzan Şahin4, Demet Hacıseyitoğlu5, Fusun Can6, Onder Ergonul6. 1. Infectious Diseases and Clinical Microbiology Department, Kartal Koşuyolu Training and Research Hospital, Istanbul, Turkey. Electronic address: oergonul@ku.edu.tr. 2. Infectious Diseases and Clinical Microbiology Department, School of Medicine, Medeniyet University, Istanbul, Turkey. 3. Infectious Diseases and Clinical Microbiology Department, Kartal Koşuyolu Training and Research Hospital, Istanbul, Turkey. 4. Infectious Diseases and Clinical Microbiology Department, Lütfü Kırdar Training and Research Hospital, Istanbul, Turkey. 5. Clinical Microbiology Department, Lütfü Kırdar Training and Research Hospital, Istanbul, Turkey. 6. Infectious Diseases and Clinical Microbiology Department, Koç University School of Medicine, Istanbul, Turkey.
Abstract
BACKGROUND: The aim of this study was to determine the effect of colistin resistance and other predictors on fatality among patients with Klebsiella pneumoniae bloodstream infections (Kp-BSI) and to describe the effect of amikacin and tigecycline on the outcome in an OXA-48 dominant country. METHOD: This was a retrospective study performed among patients >16 years of age in a tertiary hospital with 465 beds. All cases had ≥1 positive blood culture for K. pneumoniae 48 h after admission. RESULTS: Among 210 patients with Kp-BSI, the 30-day mortality rate after isolation of the microorganism was 58%. The rate of carbapenem resistance was higher (64% vs. 38%, p < 0.001) and the colistin minimum inhibitory concentration (MIC) was elevated (7 vs. 4, p < 0.029) among the patients who died. Among the colistin-resistant K. pneumoniae, the rates of OXA-48, ST101, and NDM-1 were 78%, 67%, and 35%, respectively. Amikacin was added to the treatment of 13 patients with carbapenem and colistin-resistant Kp-BSI and 77% survived (p < 0.001). Tigecycline was added to the treatment of 24 patients with carbapenem and colistin-resistant Kp-BSI, and the 30-day mortality rate was 71% (p = 0.576). In the multivariate analysis, carbapenem resistance (odds ratio (OR) 5.2, 95% confidence interval (CI) 2.47-10.9, p < 0.001) and increasing APACHE II score (OR 1.19, 95% CI 1.12-1.26, p < 0.001) were significantly associated with 30-day mortality. The addition of amikacin to the treatment regimen (OR 0.05, 95% CI 0.01-0.23, p < 0.001) was significantly beneficial. CONCLUSIONS: Carbapenem resistance, increasing MIC of colistin, and the lungs as the source of the infection were significantly associated with 30-day mortality. The empirical use of combined active aminoglycosides was found to be beneficial in the treatment of colistin-resistant K. pneumoniae infections.
BACKGROUND: The aim of this study was to determine the effect of colistin resistance and other predictors on fatality among patients with Klebsiella pneumoniae bloodstream infections (Kp-BSI) and to describe the effect of amikacin and tigecycline on the outcome in an OXA-48 dominant country. METHOD: This was a retrospective study performed among patients >16 years of age in a tertiary hospital with 465 beds. All cases had ≥1 positive blood culture for K. pneumoniae 48 h after admission. RESULTS: Among 210 patients with Kp-BSI, the 30-day mortality rate after isolation of the microorganism was 58%. The rate of carbapenem resistance was higher (64% vs. 38%, p < 0.001) and the colistin minimum inhibitory concentration (MIC) was elevated (7 vs. 4, p < 0.029) among the patients who died. Among the colistin-resistant K. pneumoniae, the rates of OXA-48, ST101, and NDM-1 were 78%, 67%, and 35%, respectively. Amikacin was added to the treatment of 13 patients with carbapenem and colistin-resistant Kp-BSI and 77% survived (p < 0.001). Tigecycline was added to the treatment of 24 patients with carbapenem and colistin-resistant Kp-BSI, and the 30-day mortality rate was 71% (p = 0.576). In the multivariate analysis, carbapenem resistance (odds ratio (OR) 5.2, 95% confidence interval (CI) 2.47-10.9, p < 0.001) and increasing APACHE II score (OR 1.19, 95% CI 1.12-1.26, p < 0.001) were significantly associated with 30-day mortality. The addition of amikacin to the treatment regimen (OR 0.05, 95% CI 0.01-0.23, p < 0.001) was significantly beneficial. CONCLUSIONS:Carbapenem resistance, increasing MIC of colistin, and the lungs as the source of the infection were significantly associated with 30-day mortality. The empirical use of combined active aminoglycosides was found to be beneficial in the treatment of colistin-resistant K. pneumoniae infections.