Eun Ju Choo

Clinical Features and Outcomes of Bacteremia Caused by Enterococcus casseliflavus and Enterococcus gallinarum: Analysis of 56 Cases

The clinical significance and virulence potential of Enterococcus casseliflavus/flavescens and Enterococcus gallinarum are still uncertain. We retrospectively analyzed 56 cases of significant bacteremia caused by E. casseliflavus or E. gallinarum. Of these cases, 25 (44.6%) were associated with polymicrobial bacteremia, and 43 (76.8%) were associated with entry via the biliary tract. Resistance to vancomycin was observed in 17 (30.4%) of these 56 patients, and this resistance was significantly associated with E. gallinarum bacteremia (adjusted odds ratio [AOR], 10.56; 95% confidence interval [CI], 2.41-46.27) and bacteremia without biliary tract origin (AOR, 6.74; 95% CI, 1.44-31.67). The crude mortality rate was 13%, and the bacteremia-related mortality rate was 1.9%. In conclusion, bacteremia due to E. casseliflavus and E. gallinarum is commonly associated with biliary tract disease and may be associated with a low risk of mortality.

Early Acute Kidney Injury Is a Risk Factor That Predicts Mortality in Patients Treated with Colistin

The nephrotoxicity of colistin has been reported in the literature. A previous report has shown that acute kidney injury (AKI) occurred after an average of 13.5 days, but we have experienced that AKI developed with colistin administration earlier. We investigated clinical features of patients who developed AKI according to the time of AKI development after colistin use. We retrospectively collected the data of the patients who were admitted to 4 hospitals between January 2007 and May 2009. This study included 119 patients who had received intravenous colistin for over 72 h. We compared the early AKI group (AKI developed within 7 days) with the late AKI group. The patients’ age was 64.1 ± 14.0 years. AKI occurred in 65 of the 119 patients (54.6%). The duration of colistin use was 7.7 ± 6.4 days. AKI occurred in 46 patients within 7 days after colistin treatment and in 19 patients after 7 days. The patients with early AKI had a higher mortality rate than those with late AKI (OR: 4.37, 95% CI: 1.34, 14.18). In conclusion, clinicians might be cautioned that the mortality rate is higher for the patients with early occurrence of AKI than that for the patients with late occurrence of AKI.

Serratia Bacteremia in a Large University Hospital: Trends in Antibiotic Resistance During 10 Years and Implications for Antibiotic Use

OBJECTIVE To identify antibiotic resistance trends and risk factors for resistance of Serratia species to third-generation cephalosporins. DESIGN Retrospective survey of medical records. SETTING A 2,200-bed, tertiary-care hospital. PATIENTS One hundred twenty-two patients with Serratia bacteremia between January 1991 and June 2001. METHODS Infectious disease physicians collected data from medical records regarding patient demographics, underlying disease or condition, portal of entry, microorganism, antibiogram, complications, antibiotics received, and outcome. RESULTS Among 122 Serratia isolates, 117 (95.9%) were Serratia marcescens and 110 (90.2%) were of nosocomial origin. During the study period, the 122 isolates showed a high rate of resistance to third-generation cephalosporins (45.9%) and extended-spectrum penicillins (56.6%). The resistance rate to ciprofloxacin was 32.0%. The resistance rate to third-generation cephalosporins increased from 31.7% for 1991 to 1995 to 54.9% for 1996 to 1998 and 50.0% for 1999 to 2001. In the multivariate analysis, prior use of a second-generation cephalosporin (adjusted odds ratio [OR], 5.90; 95% confidence interval [CI90], 1.41 to 24.6; P = .015) or a third-generation cephalosporin (OR, 3.26; CI95, 1.20 to 8.87; P = .020) was a strong independent risk factor for resistance to third-generation cephalosporins. The overall case-fatality rate was 25.4% (Serratia bacteremia-related case-fatality rate, 13.1%). CONCLUSION Prior use of a second- or third-generation cephalosporin was the most important risk factor for bacteremia with Serratia resistant to third-generation cephalosporins, suggesting the need for antibiotic control. The potential role of patient-to-patient spread could not be fully evaluated in this retrospective study.

Acquisition of extensive drug-resistant Pseudomonas aeruginosa among hospitalized patients: risk factors and resistance mechanisms to carbapenems.

Extensive drug-resistant Pseudomonas aeruginosa (XDRPA) strains, defined as resistant to all available antipseudomonal antibiotics, have been reported recently. This study aimed to investigate the risk factors for XDRPA acquisition by patients and the resistance mechanisms to carbapenems. From June to November 2007, XDRPA isolates were collected from patients in eight tertiary care hospitals. A case-control study was performed to determine factors associated with XDRPA acquisition. EDTA-imipenem disc synergy tests, and polymerase chain reaction amplification and sequencing were performed to detect the presence of metallo-β-lactamases (MBLs). Risk factor analysis was performed for 33 patients. Mechanical ventilation [odds ratio (OR) 8.2, 95% confidence interval (CI) 1.3-52.2; P = 0.026] and APACHE II score (OR 1.2, 95% CI 1.0-1.3; P = 0.007) were identified as independent risk factors for XDRPA acquisition. Pulsed-field gel electrophoresis of XDRPA identified clonal epidemic isolates co-existing with sporadic isolates. Eight of 43 (19%) XDRPA isolates were shown to produce MBLs; four produced VIM-2 and four produced IMP-6. This study suggests a major role for mechanical ventilation in XDRPA acquisition. Moreover, pulsed-field gel electrophoresis identified a clonal epidemic within hospitals. Taken together, these results suggest that patient-to-patient transmission contributes to XDRPA acquisition in Korea.

Prevalence of Latent Tuberculosis Infection among Health Care Workers in South Korea: A Multicenter Study

Background We investigated the prevalence of latent tuberculosis infection (LTBI) among the health care workers (HCWs) and analyzed its risk factors in South Korea. Methods A standard questionnaire regarding the baseline demographics and risk factors for LTBI was given to each participant and tuberculin skin test (TST), QuantiFERON-TB GOLD In-Tube (QFT-GIT) assay, and chest radiography were performed. Results A total of 493 participants, 152 (30.8%) doctors and 341 (69.2%) nurses were enrolled in eight tertiary referral hospitals. The mean age of the subjects was 30.6 years old, and 383 (77.7%) were female. Of the 152 doctors, 63 (41.4%) and 36 (23.7%) were positive by TST and by QTF-GIT, respectively, and among the 341 nurses, 119 (34.9%) and 49 (14.4%) had positive TST and QFT-GIT results, respectively. Overall, the agreement between the two tests was 0.22 by the chance corrected proportional agreement rate (kappa coefficient) in 493 subjects. Experience of working in tuberculosis (TB)-related departments was significantly associated with positive LTBI test results by QFT-GIT assay, not by TST. In multivariate analysis, only age was independently associated with increased risk of a positive TST result, while age and experience of working in TB-related departments (odds ratio, 2.29; 95% confidence interval, 1.01-5.12) were independently associated with increased risk of a positive QFT-GIT result. Conclusion A high prevalence of LTBI was found among South Korean HCWs. Considering the association between the experience of working in TB-related departments and high risk of LTBI, QFT-GIT may be a better diagnostic test for LTBI than TST in HCWs.

Risk Factors for Mortality in Patients with Acinetobacter baumannii Bacteremia.

Background Acinetobacter baumannii, an opportunistic nosocomial pathogen that can cause significant morbidity and mortality, has emerged as a worldwide problem. The aim of this study was to evaluate the risk factors for mortality in patients with A. baumannii bacteremia. Materials and Methods We retrospectively evaluated 118 patients who had A. baumannii bacteremia between July 2003 and December 2011. The aim of this study was to identify the 30-day mortality in patients with A. baumannii bacteremia and relevant risk factors. Results The bacteremia-related 30-day mortality rate was 34.1%. Univariate analysis revealed that the risk factors for mortality included malignancy, longer hospital stay before bacteremia, intensive care unit (ICU) stay at the time of bacteremia, mechanical ventilation, use of a central venous catheter, unknown origin of bacteremia, bacteremia due to pneumonia, antimicrobial resistance to carbapenems, and elevated Acute Physiology and Chronic Health Evaluation II and Pitt bacteremia scores. Multivariate logistic regression analysis revealed that resistance to carbapenems (odds ratio [OR]: 4.01, 95% confidence interval [CI]: 1.51 to 0.68, P = 0.005), need for mechanical ventilation (OR: 3.97, 95% CI: 1.41 to 11.13, P = 0.005), and presence of malignancy (OR: 4.40, 95% CI: 1.60 to 12.08, P = 0.004) were significantly related to mortality risk. Conclusions Risk factors such as resistance to carbapenems, mechanical ventilation, and presence of malignancy were found to be associated with high mortality rates in the patients with A. baumannii bacteremia.

Tuberculous peritonitis in cirrhotic patients: comparison of spontaneous bacterial peritonitis caused by Escherichia coli with tuberculous peritonitis.

The aim of this study was to compare the characteristics of tuberculous peritonitis (TP) and spontaneous bacterial peritonitis (SBP) in cirrhotic patients. In a retrospective review of the medical records of a single tertiary hospital between 1988 and 2006, 15 patients met the diagnostic criteria TP and liver cirrhosis. For comparison, we randomly selected 3 cirrhotic patients with SBP caused by Escherichia coli for each cirrhotic patient with TP. Compared to SBP, TP in cirrhotic patients was more frequently associated with extra-peritoneal tuberculosis (TP vs SBP: 53.3% vs 0%), an insidious onset (≥2 weeks; 60% vs 2.2%), and Child–Pugh classification class B at onset (80% vs 8.9%) (p<0.05). Compared to SBP, TP was associated with lower white blood cell count in ascites (TP vs SBP: 2.0±2.2×103/mm3 vs 7.2±7.5×103/mm3), a higher proportion of mononuclear leukocytes (lymphocytes and monocytes) in ascites (88.9±9.5% vs 16.6±15.3%), higher protein concentration in ascites (3.1±1.7 g/dl vs 1.2±0.3 g/dl), and higher adenosine deaminase activity in ascites (62.3±31.8 U/l vs 6.9±3.1 U/l) (p<0.05). TP should be suspected in cirrhotic patients with relevant clinical manifestations and characteristics of ascites.

The burden of nosocomial staphylococcus aureus bloodstream infection in South Korea: a prospective hospital-based nationwide study

BackgroundWe estimated the nationwide burden of nosocomial S. aureus bloodstream infection (SA-BSI), a major cause of nosocomial infection, in South Korea.MethodsTo evaluate the nationwide incidence of nosocomial SA-BSI, cases of SA-BSI were prospectively collected from 22 hospitals with over 500 beds over 4?months. Data on patient-days were obtained from a national health insurance database containing the claims data for all healthcare facilities in South Korea. The additional cost of SA-BSI was estimated through a matched case?control study. The economic burden was calculated from the sum of the medical costs, the costs of caregiving and loss of productivity.ResultsThree hundred and thirty nine cases of nosocomial SA-BSI were included in the study: 254 cases of methicillin-resistant SA-BSI (MRSA-BSI) and 85 cases of methicillin-susceptible SA-BSI (MSSA-BSI). Death related to BSI occurred in 81 cases (31.9%) of MRSA-BSI and 12 cases (14.1%) of MSSA-BSI. The estimated incidence of nosocomial MRSA-BSI was 0.12/1,000 patient-days and that of nosocomial MSSA-BSI, 0.04/1,000 patient-days. The estimated annual cases of nosocomial BSI were 2,946 for MRSA and 986 for MSSA in South Korea. The additional economic burden per case of nosocomial SA-BSI was US

Severe influenza treatment guideline

20,494 for MRSA-BSI and

Immunogenicity and safety of diphtheria-tetanus vaccine in adults.

6,914 for MSSA-BSI. Total additional annual cost of nosocomial SA-BSI was