Dong Sik Jung

Scoring systems for prediction of mortality in patients with intensive care unit-acquired sepsis: a comparison of the Pitt bacteremia score and the Acute Physiology and Chronic Health Evaluation II scoring systems.

This study compares the effectiveness of the Pitt bacteremia score, the Charlson weighted index of comorbidity, and the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring systems for the prediction of mortality in intensive care unit (ICU) patients with sepsis using the retrospective observational method on 134 patients with ICU-acquired sepsis. The statistical analyses show several important findings. First, Pitt bacteremia score is significantly correlated with the APACHE II scoring system (correlation coefficient = 0.738, P < 0.001). Second, the APACHE II scoring system, the Pitt bacteremia score, and the Charlson weighted index of comorbidity are independently correlated with mortality. Third, the Pitt bacteremia score and the APACHE II scores are positively related to mortality in patients with ICU-acquired sepsis. As the result of the analyses, the mortality rate in patients with sepsis in the ICU is better predicted with the Pitt bacteremia score because it provides better estimation of sensitivity and specificity than the APACHE II scoring system and the Charlson weighted index of comorbidity.

Prevalence and characterization of extended-spectrum β-lactamase-producing Enterobacteriaceae isolated in Korean hospitals

Prevalence and characteristics of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in Korean hospitals were assessed. A total of 1484 clinical Enterobacteriaceae isolates were collected from 8 tertiary-care hospitals in various regions of Korea over a 3-month period (June to August) in 2005. Among 546 Klebsiella pneumoniae isolates, 123 isolates (22.4%) showed ESBL-producing activity, and 47 (10.2%) of 460 isolates of Escherichia coli were ESBL producers. Of the Enterobacter cloacae isolates, 16.2% (17/105) evidenced ESBL-producing activity. The most prevalent ESBLs were SHV-12 and CTX-M-14 in K. pneumoniae and E. coli, respectively. In E. cloacae, SHV-12 was also the most prevalent. Prevalence of ESBL production differed among the specimens. Although the K. pneumoniae isolates from urine and aspirates evidenced high ESBL production rates (35.4% and 57.1%, respectively), those from sputum, blood, and pus showed relatively low ESBL production rates (17.0%, 14.8%, and 5.3%, respectively). However, E. coli isolates obtained from sputum showed significantly higher ESBL production rates (37.5%) than were seen in samples obtained from other sources, but those obtained from urine showed lower ESBL production rates (8.3%). These significant differences in ESBL-producing K. pneumoniae and E. coli isolates among the isolated specimens should be examined further, with an eye toward the implications of this research in clinical settings.

Impact of inappropriate antimicrobial therapy on outcome in patients with hospital-acquired pneumonia caused by Acinetobacter baumannii.

OBJECTIVES The purpose of this study was to evaluate the impact of inappropriate antimicrobial therapy on the outcome of patients with hospital-acquired pneumonia (HAP) caused by Acinetobacter baumannii. METHODS All cases of HAP caused by A. baumannii from January 2000 to March 2006 at the Samsung Medical Center (Seoul, Korea) were analyzed retrospectively. RESULTS A total of 116 patients with clinically significant Acinetobacter HAP were enrolled. Among the A. baumannii isolates, 60.3% showed multi-drug resistance (MDR), 16.4% were found to have imipenem resistance, and 15.5% had pan-drug resistance (PDR). The mean APACHE II score of the patients was 22.3 +/- 7.9. The overall in-hospital and pneumonia-related mortality rates were 47.4% and 37.9%, respectively. The univariate analysis showed that the factors associated with pneumonia-related mortality were: MDR, PDR, high APACHE II score, inappropriate empirical antimicrobial therapy, and inappropriate definitive antimicrobial treatment (All p < 0.05). Among these, a high APACHE II score and inappropriate definitive antimicrobial therapy were found to be independent factors associated with a high mortality, after adjustment for other variables. CONCLUSIONS The appropriate definitive antimicrobial therapy should be provided in patients with HAP caused by A. baumannii.

Two distinct clones of carbapenem-resistant Acinetobacter baumannii isolates from Korean hospitals

We investigated the characteristics of 48 carbapenem-resistant Acinetobacter baumannii isolates collected from 5 tertiary care hospitals in Korea by multilocus sequencing typing, pulsed-field gel electrophoresis, and polymerase chain reaction amplification of the antimicrobial resistance determinants. We identified 2 distinct main clones of carbapenem-resistant A. baumannii isolates, which showed different antimicrobial resistance profiles and are also differentiated by the kinds of oxacillinase (OXA) carbapenemases and Acinetobacter-derived cephalosporinase (ADC) beta-lactamases. One main clone, ST22:A, had 27 carbapenem-resistant isolates (56.3%), showed high polymyxin B and colistin resistances (33.3% and 37.0%, respectively), and contained both bla(OXA-51-like) and bla(OXA-23-like) genes and the bla(ADC-29) or bla(ADC-30) gene. In contrast, the other main clone, ST28:B, included 15 isolates (31.3%), showed complete susceptibilities to polymyxin B and colistin, and contained only the bla(OXA-51-like) gene and bla(ADC-31) or bla(ADC-32) genes. The distribution of these main carbapenem-resistant A. baumannii clones did not relate to locality, indicating that they are widespread in Korean hospitals. In addition, we found new types of PER beta-lactamases, PER-6.

Paenibacillus konsidensis sp. nov., isolated from a patient

A Gram-positive, rod-shaped bacterium, designated strain LBY(T), was isolated from the blood of a Korean patient. The organism could not be identified based on conventional clinical microbiological methods. 16S rRNA gene sequencing and phylogenetic analysis revealed that it belonged to the genus Paenibacillus, but was distinct from recognized Paenibacillus species. Strain LBY(T) was related most closely to the type strains of Paenibacillus macerans and Paenibacillus popilliae, with 16S rRNA gene sequence similarities of 96.2 and 95.4%, respectively. The major fatty acids of strain LBY(T) were anteiso-C(15:0) (43.8%), C(16:0) (10.4%), iso-C(16:0) (10.3%), iso-C(15:0) (9.2%) and anteiso-C(17:0) (8.3%). On the basis of biochemical characteristics, fatty acid composition and comparative 16S rRNA gene sequence analysis, strain LBY(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus konsidensis sp. nov. is proposed. The type strain is LBY(T) (=ABB-ID-KSY9(T)=KCTC 13165(T)=JCM 14798(T)).

Imported malaria in Korea: a 13-year experience in a single center.

The incidence of imported malaria has been increasing in Korea. We reviewed data retrospectively to evaluate the epidemiology, clinical features, and outcomes of imported malaria from 1995 to 2007 in a university hospital. All patients diagnosed with imported malaria were included. Imported malaria was defined as a positive smear for malaria that was acquired in a foreign country. A total of 49 patients (mean age, 35.7 year; M : F = 38 : 11) were enrolled. The predominant malarial species was Plasmodium falciparum (73.5%), and the most frequent area of acquisition was Africa (55.1%), followed by Southeast Asia (22.4%) and South Asia (18.4%). Fourteen-patients (30.6%) suffered from severe malaria caused by P. falciparum and 1 patient (2.0%) died of multiorgan failure. Most of the patients were treated with mefloquine (79.2%) or quinine (10.2%); other antimalarial agents had to be given in 13.2% treated with mefloquine and 44.4% with quinine due to adverse drug events (ADEs). P. falciparum was the most common cause of imported malaria, with the majority of cases acquired from Africa, and a significant number of patients had severe malaria. Alternative antimalarial agents with lower rates of ADEs might be considered for effective treatment instead of mefloquine and quinine.

An adult case of chronic active Epstein-Barr virus infection with interstitial pneumonitis.

Chronic active Epstein-Barr virus (CAEBV) infection is characterized by persistent infectious mononucleosis-like symptoms, an unusual pattern of Epstein-Barr virus (EBV) antibodies, detection of the EBV genome in affected tissues or peripheral blood, and chronic illness that cannot be attributed to any other known disease. This is the first reported Korean case of an immunocompetent adult with CAEBV-associated interstitial pneumonitis. A 28-year-old female was admitted with a fever that persisted for 3 weeks. She had multiple lymphadenopathy, hepatosplenomegaly, pancytopenia, and elevated serum aminotransferase levels. Serology for antibodies was positive and chest computed tomography showed diffuse ground glass opacities in both lungs. Histopathology of the lung tissue showed lymphocyte infiltration, and EBV DNA was detected in those lymphocytes using in situ hybridization with an EBV-encoded RNA probe. After 1 month of hospitalization, she improved without specific treatment.

Clinical and Therapeutic Implications of Aeromonas Bacteremia: 14 Years Nation-Wide Experiences in Korea.

Background To elucidate the clinical presentation, antimicrobial susceptibility, and prognostic factors of monomicrobial Aeromonas bacteremia in order to determine the most effective optimal therapy. Materials and Methods We reviewed the medical records of Aeromonas bacteremia patients for the period January 2000 to December 2013 in a retrospective multi-center study. Results A total of 336 patient records were reviewed, with 242 having community-acquired bacteremia. The major clinical infections were of the hepatobiliary tract (50.6%) and peritonitis (18.5%), followed by primary bacteremia (17.9%). The infections usually occurred in patients with malignancy (42.3%), hepatic cirrhosis (39.3%), or diabetes mellitus (25.6%). High antimicrobial-resistance rates (15.5% for ceftriaxone, 15.5% for piperacillin/tazobactam) were noted. However, resistance to carbapenem and amikacin was only 9.8% and 3.0%, respectively. Aeromonas hydrophila (58.9%) was the most common pathogen, followed by Aeromonas caviae (30.4%). The severity of A. caviae bacteremia cases were less than that of A. hydrophila or Aeromonas veronii bacteremia (P <0.05). A. hydrophila showed higher antimicrobial resistance than did other Aeromonas species (P <0.05). Patients with hospital-acquired bacteremia were more likely to have severely abnormal laboratory findings and relatively high antimicrobial-resistance rates. Mortality was associated with metastatic cancer, shock, delayed use of appropriate antimicrobial agents, increased prothrombin time, and increased creatinine level (P <0.05). Conclusions Aeromonas species should be considered one of the causative agents of bacteremia in patients with intra-abdominal infections or malignancies. Although ceftriaxone-resistant Aeromonas bacteremia was not statistically related to mortality in this study, it was associated with severe clinical manifestations and laboratory abnormalities. Appropriate antibiotics, including carbapenem, should be administered early, especially in Aeromonas bacteremia patients with shock and impaired renal function.

Is adjunctive corticosteroid beneficial in pneumococcal meningitis in a region with high rates of resistance to penicillin and ceftriaxone

The role of adjunctive corticosteroids remains controversial in meningitis by penicillin-resistant pneumococci. We determined the effect of adjunctive corticosteroids in adults with pneumococcal meningitis in a region with a high rate of penicillin resistance. A multicenter, retrospective cohort study was conducted between 1998 and 2008 in Korea. The mortality and neurological sequelae were evaluated. Among 93 patients with pneumococcal meningitis, adequate adjunctive corticosteroids were given in 45.2%. The penicillin resistance rate was 60.0%, and 42.1% were nonsusceptible to ceftriaxone. The 30-day mortality rates in the group receiving adequate corticosteroid therapy, the group in which corticosteroid was not given, and that inadequately given were 24.3, 31.6, and 27.3%, respectively, and there was no difference between the groups. The rates of development of neurological sequelae were 34.3, 33.3, and 43.5%, respectively. Multivariate analysis showed that adequate corticosteroids did not reduce mortality (HR 0.773, 95% CI 0.293–2.040) and neurologic sequelae (HR 0.604, CI 0.262–1.393). Propensity-adjusted analysis showed that adjunctive corticosteroid was not associated with time to death (HR 0.949, CI 0.374–2.408), however, a decreasing tendency was shown in neurologic sequelae in the adequate corticosteroid group (HR 0.479, CI 0.207–1.110). In conclusion, adjunctive corticosteroids did not affect mortality in adults with pneumococcal meningitis in a region with high rates of resistance to penicillin and ceftriaxone; however, the patients receiving adequate corticosteroid therapy tended to develop neurologic sequelae less frequently.

Impact of high MIC of fluconazole on outcomes of Candida glabrata bloodstream infection: a retrospective multicenter cohort study

To evaluate the impacts of fluconazole minimum inhibitory concentration (MIC) according to primary antifungal agents on Candida glabrata bloodstream infection (BSI), a multicenter retrospective cohort study was conducted in Korea, concerning the time period from January 2010 to February 2016. A total of 197 adult patients with C. glabrata BSI were included in the study, and neutropenia (P = 0.026), APACHE II score (P = 0.004), and fluconazole resistance (HR 3.960, 95% CI 1.395-11.246, P = 0.010) were associated with 30-day mortality in multivariate analysis. In subgroup analysis, fluconazole MIC = 32 μg/mL in the azole-treated group (HR 6.691, 95% CI 1.569-28.542, P = 0.010) and fluconazole MIC ≥ 64 μg/mL in the non-azole-treated group (HR 3.337, 95% CI 1.183-9.411, P = 0.023) showed the highest hazard ratio (HR) for 30-day mortality. Increased fluconazole MIC was associated with poor outcome both in azole- and non-azole-treated patients with C. glabrata BSI.