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To evaluate the association between serum prostate-specific antigen (PSA) concentration from a screening test and prostate cancer mortality in an Asian population.We included 118,665 men in the Korean Heart Study, a large prospective cohort study of participants who voluntarily underwent private health examinations that included PSA-based prostate cancer screening. The baseline visit occurred between January 1994 and December 2004, and follow-up was through December 2011. Deaths from prostate cancer were ascertained from the underlying cause of death from a computerized search of death certificate data from the National Statistical Office in Korea. We used the Cox proportional hazards regression to estimate the association between serum PSA and risk of prostate cancer death adjusting the baseline age, cigarette smoking status, and body mass index.During 1,381,901 person-years of follow-up, 6036 men died of any cause, and of these, 56 men died of prostate cancer. The multivariate-adjusted hazard ratio for prostate cancer death statistically significantly increased across PSA concentrations (P trend.0001). The hazard ratio increased 7% per 1-ng/mL increase in PSA. The association between PSA concentration and death from prostate cancer was stronger in younger than in older men and in heavier than leaner men.In conclusion, an increased screening PSA level is associated with an increased risk of prostate cancer death in Korean men. Our findings may have implications for the development of targeted PSA cutpoints for biopsy recommendation.

Objective Knowledge regarding the prevalence and distribution of human papillomavirus (HPV) genotyping in healthy women is important in establishing strategies for cervical cancer screening and HPV vaccination. Methods A total of 18,170 women who visited a Korean Medical Institute for health check-ups were recruited retrospectively; they underwent HPV genotyping and conventional cervical cytology. An HPV DNA test was performed using the Anyplex™ II HPV 28 detection system (Seegene) or HPV Liquid Bead Microarray (Osang Healthcare). The distribution of HPV genotypes was assessed according to cervical cytology and age. Results HPV was detected in 3,037 (16.71%) of the 18,170 women enrolled, and 2,268 (12.48%) were positive for high-risk (HR) HPV. In total, HPV 53 (9.69% of all detected HPV viruses) was the most common type; HPV 58 (7.90%) and 52 (7.81%) were also common. HPV 54 (6.99%) was common in low-risk subjects. Overall and in the normal cytology group, the most common HPV genotype was HPV 53, whereas HPV 58 was more common in women who had atypical squamous cells of undetermined significance or low-grade squamous intraepithelial neoplasia cervical cytology. In addition, HPV 16 was the most common type in cases with high-grade squamous intraepithelial neoplasia (HSIL)/atypical squamous cells-cannot exclude HSIL. Among women with normal cytology, 76 of 231 (32.9%) women under 24 years of age were positive for HR HPV, whereas 84 of 852 (9.9%) women aged 55-59 years were positive. Conclusion HPV 53 was the most prevalent genotype in healthy women. Distribution of HPV genotypes varied with cervical cytology and age. Our study provides important baseline data for the recently implemented national HPV vaccination program.

In this study, the characteristics of carbapenem-resistant Enterobacteriaceae (CRE) isolates from Korea was investigated. A total of 22 CRE isolates were investigated, and most were identified as Klebsiella pneumoniae (16 isolates). In vitro antimicrobial susceptibility testing, multilocus sequence typing, and pulsed-field gel electrophoresis were performed. Extended-spectrum β-lactamase (ESBL) and carbapenemase genes were detected using gene amplification and sequencing. Efflux pump activity and inactivating mutations in OmpK35/36 were also investigated. Among 22 CRE isolates, only 5 produced metallo-β-lactamases (3 NDM-1, one VIM-2 and one IMP-1). Four and 2 K. pneumoniae and Serratia marcescens isolates showed resistance to polymyxins, respectively, and 2 CRE isolates (1 K. pneumoniae and C. freundii) were resistant to tigecycline. The prevalent carbapenem resistance mechanism found in K. pneumoniae might be porin defects. The most prevalent clone of carbapenem-resistant K. pneumoniae was ST11 (56.3%), which is the most frequently identified clone among ESBL-producing K. pneumoniae isolates from Korea. Three NDM-1-producing K. pneumoniae isolates belonged to a single clone (ST340) despite their different antimicrobial susceptibilities. In the present study, the clonal dissemination of carbapenem-resistant K. pneumoniae isolates (ST11) and NDM-1-producing K. pneumoniae isolates (ST340) was determined. Polymyxin- and tigecycline-resistant CRE isolates were also identified, which limits treatment options for infections causes by these organisms.

Carbapenem-resistant Gram-negative bacteria (CR-GNB) have emerged and disseminated worldwide, become a great concern worldwide including Korea. The prevalence of fecal carriage of imipenem-resistant Gram-negative bacteria (IR-GNB) in persons in Korea was investigated. Stool samples were collected from 300 persons upon medical examination. Samples were screened for IR-GNB by using MacConkey agar with 2 μl/ml imipenem. Species were identified by 16S rRNA gene sequence analysis, and antimicrobial susceptibility was determined by the broth microdilution method. In total, 82 IR-GNB bacterial isolates were obtained from 79 (26.3%) out of 300 healthy persons. Multilocus sequence typing analysis showed very high diversity among IR P. aeruginosa, S. maltophilia, and E. cloacae isolates, and pulsed-field gel electrophoresis revealed five main pulsotypes of IR P. mirabilis. As for the presence of metallo-β-lactamases (MBLs), only one IMP-25-producing S. marcescens isolate was identified. Although only one carbapenemase-producing isolate was identified, the high colonization rates with IR-GNB isolates in this study is notable because carriers may be a reservoir for the dissemination of resistant pathogens within the community as well as in health care institutions.

Tigecycline has broad spectrum antimicrobial activity and is approved for complicated intra-abdominal infections, complicated skin and soft tissue infections, and community-acquired pneumonia. There are few data on clinical experience of tigecycline in hospital-acquired pneumonia (HAP) and Acinetobacter spp. infection.A retrospective study was performed at eight hospitals in Korea from May 2009 to January 2010. Adult patients treated with tigecycline regardless of their source of infection or pathogens were enrolled.Tigecycline was administered in 108 patients. Pneumonia was the most common infection (43.5%), followed by skin and soft tissue infections (20.4%). Acinetobacter baumannii was isolated from 83 patients (76.9%) accounting for 50.3% of isolated pathogens, showing a resistance rate of 67.5% to carbapenems. Superinfection was identified in 32 patients (29.6%). Pseudomonas aeruginosa was most common microorganism causing superinfection (46.9%). Overall 30-day mortality rate was 52.9%. Thirty-day mortality rate of HAP and Acinetobacter spp. infection was 60.5% and 59.4%, respectively.Tigecycline can be considered as an alternative therapy in patients with HAP or infections caused by Acinetobacter spp., especially extensively drug-resistant A. baumannii.

The identification of clinical characteristics that could identify patients at high risk for Pseudomonas aeruginosa or Acinetobacter baumannii bacteremia would aid clinicians in the appropriate management of these life-threatening conditions, especially in patients admitted to the emergency department (ED) with community-onset infections. To determine clinical risk factors for P aeruginosa or A baumannii bacteremia in patients with community-onset gram-negative bacteremia (GNB), a post hoc analysis of a nationwide bacteremia surveillance database including patients with microbiologically documented GNB was performed. Ninety-six patients with P aeruginosa or A baumannii bacteremia were compared with 1230 patients with Escherichia coli or Klebsiella pneumoniae bacteremia. A solid tumor or hematologic malignancy was more likely to be associated with P aeruginosa or A baumannii bacteremia, whereas concurrent neurologic disease was less frequently seen. In regards to the site of infection, pneumonia was more common in P aeruginosa or A baumannii bacteremia, whereas a urinary tract infection was less frequently seen. Factors associated with P aeruginosa or A baumannii bacteremia in multivariate analysis included pneumonia (odds ratio [OR], 3.60; 95% confidence interval [CI], 1.86-6.99), hematologic malignancy (OR, 2.71; 95% CI, 1.26-5.84), male sex (OR, 2.17; 95% CI, 1.31-3.58), solid tumor (OR, 1.89; 95% CI, 1.15-3.12), and health-care–associated infection (OR, 1.88; 95% CI, 1.48-2.41). Our data suggest that an initial empirical antimicrobial coverage of P aeruginosa or A baumannii bacteremia should be seriously considered in patients with pneumonia, a hematologic malignancy, solid tumor, or health-care–associated infection, when GNB is suspected, even in community-onset infections.

The objectives of this study were to investigate antibiotic resistance in urinary pathogens from Korean patients with uncomplicated acute pyelonephritis (UAPN), and to determine the effect of fluoroquinolone (FQ) resistance on clinical outcome in those patients with UAPN initially treated with FQ. Clinical and microbiologic data for all the APN patients attending 14 hospitals in South Korea in 2008 were collected retrospectively. Urinary pathogens were identified in 719 cases, and Escherichia coli was the most common pathogen (661/719, 91.9%). Antibiotic susceptibilities to several E. coli antibiotics were as follows: ciprofloxacin, 84.1%; trimethoprim-sulfamethoxazola (TMP-SMX), 67.2%; and extended-spectrum beta-lactamase-negative, 92.4%. FQ was the most frequent antibiotic prescribed for UAPN (45.3% intravenously and 53.9% by mouth). We compared clinical outcomes and hospital days in patients with FQ-resistant (32) and FQ-sensitive E. coli (173) who received FQ as initial empirical therapy. Clinical cure was higher in the FQ-sensitive group (78% vs. 91%, p=0.027), and hospital days were longer in the FQ-resistant group (9.6±5.5 days vs. 7±3.5 days, p=0.001). In conclusion, FQ-sensitivity of E. coli from UAPN was 84.1%. FQ treatment of UAPN caused by FQ-resistant E. coli has a lower cure rate and involves longer hospital stay than FQ treatment of cases caused by FQ-sensitive E. coli.

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.

The purpose of this study was to evaluate clinical features and outcomes of bacteremia in patients with liver cirrhosis (LC) and determine whether underlying LC is an independent risk factor for mortality in a population of patients with different underlying diseases.From the database of nationwide surveillance studies for bacteremia, data regarding bacteremia in patients with LC were analyzed and compared with those in patients with other diseases.A total of 195 patients with LC were compared with 1659 patients with other underlying diseases. As for the site of infection, intraabdominal infection was more frequent in the LC group (P 0.001), while pneumonia, urinary tract bacteremia, and primary bacteremia were more prevalent in the other diseases group (all P 0.05). Patients with LC were more likely to have Klebsiella pneumoniae bacteremia (20.1% vs. 14.3%, P = 0.018), but less likely to have coagulase-negative staphylococcal bacteremia (5.1% vs. 10.4%, P = 0.028). The 30-day mortality rate was significantly higher in the LC group compared to the other disease group (27.2% [53/195] vs. 20.3% [336/1659], P = 0.025). Multivariate analysis revealed underlying LC as a significant predictor for mortality (OR, 2.11; 95% CI, 1.43-3.13; P 0.001), along with old age, nosocomial acquisition, pneumonia, severe sepsis, and a higher Pitt bacteremia score.The mortality rate of patients with LC was significantly higher than that of patients with other diseases when they developed bacteremia. Underlying LC was found to be one of the independent risk factors for mortality in patients with bacteremia.

This study was performed to evaluate the impact of extended-spectrum β-lactamase (ESBL)-producing bacteremia on outcome in patients with hematologic malignancy. We collected and analyzed data on 156 hematologic malignancy patients with Escherichia coli or Klebsiella pneumoniae bacteremia from the database of nationwide surveillance studies for bacteremia. Thirty-seven of the 156 patients (23.7%) harbored ESBL-producing bacteremia. No significant differences in underlying diseases were found in either group. The multivariate analysis showed that significant factors associated with ESBL-producing bacteremia were ICU care (OR = 7.03, 95% CI = 1.79–27.6) and nosocomial acquisition (OR = 5.66, 95% CI = 1.60–20.23). There was an association between prior receipt of cephalosporins and ESBL-producing bacteremia, although this association was not statistically significant (OR = 2.27, 95% CI = 0.99–5.23). The overall 30-day mortality rate of the study population was 20.4% (29/142), and the 30-day mortality rate for the ESBL group was significantly higher than that for the non-ESBL group (44.8% vs. 14.2%, P

The aim of this study was to identify risk factors for development of severe sepsis or septic shock and to evaluate the clinical impact of severe sepsis on outcome in patients with gram-negative bacteremia (GNB).From the database of a nationwide surveillance for bacteremia, patients with GNB were analyzed. Data of patients with severe sepsis or septic shock were compared with those of patient with sepsis.Of 2286 patients with GNB, 506 (22.1%) fulfilled the criteria of severe sepsis or septic shock. Factors associated with severe sepsis or septic shock in the multivariate analysis included renal disease, indwelling urinary catheter, hematologic malignancy, and neutropenia. The 30-day mortality of patients with severe sepsis or septic shock was significantly higher than that of patients with sepsis (39.5% [172/435] vs. 7.4% [86/1170]; P 0.001). Multivariable analysis revealed that solid tumor, liver disease, pulmonary disease, pneumonia, and pathogens other than Escherichia coli, which were risk factors of development of severe sepsis or septic shock, were also found to be strong predictors of mortality. Severe sepsis or septic shock was a significant factor associated with mortality (OR, 3.34; 95% CI, 2.35-4.74), after adjustment for other variables predicting poor prognosis.Severe sepsis or septic shock was a common finding in patients with GNB, predicting a higher mortality rate. Renal disease and indwelling urinary catheter were the most important risk factors significantly associated with severe sepsis or septic shock among patients with GNB.

To investigate the antimicrobial resistance, extended-spectrum β-lactamases (ESBLs) and clones of Klebsiella pneumoniae isolates causing bacteraemia or urinary tract infection (UTI) in Korea, a total of 406 K. pneumoniae isolates from patients with bacteraemia (221 isolates) and UTI (185 isolates) were collected from 10 tertiary-care Korean hospitals from July 2006 to October 2007. In vitro antimicrobial susceptibility testing was performed for all isolates and ESBL production was tested. Multilocus sequence typing (MLST) analyses were performed to characterize genotypes of ESBL-producing K. pneumoniae isolates. PFGE was performed for sequence type 11 (ST11) isolates. Forty-seven UTI isolates (25.4 %) produced ESBLs, while 30 bacteraemia isolates (13.6 %) produced ESBLs (P=0.002). Among 77 ESBL-producing isolates, thirty-two (41.6 %) produced SHV-type ESBLs. bla CTX-M genes such as bla CTX-M-14 and bla CTX-M-15 were detected in 36.4 %. MLST and PFGE analyses showed that ST11 was dominant in ESBL-producing K. pneumoniae isolates causing UTI (57.4 %) and in those causing bacteraemia (70.0 %) and has been prevalent in Korean hospitals. ST11 isolates harbour a combination of different ESBL genes. The ST11 clone of ESBL-producing K. pneumoniae isolates prevails in Korea, but most isolates might acquire ESBL genes independently or several different clones might be distributed in Korea.

Summary Objective Ciprofloxacin-resistant Escherichia coli is growing concern in clinical settings. In this study, we investigated the distribution of virulence determinants and phylogenetic groups among community-onset, ciprofloxacin-resistant E. coli isolates causing urinary tract infections (UTIs) in Korea. In addition, the evidence of clonal spread in the community was also examined. Methods From November 2006 to August 2007, 543 community-onset E. coli isolates causing UTIs were collected as part of a multicenter surveillance study. In vitro susceptibility testing was performed using broth microdilution method. Distribution of virulence determinants and phylogenetic groupings were examined. In addition, multilocus sequence typing (MLST) analysis was performed. Results In vitro antimicrobial susceptibility testing revealed that 154 isolates (28.4%) were ciprofloxacin-resistant. Of these, 129 ciprofloxacin-resistant E. coli isolates were further characterized. As a result of phylogenetic subgrouping, we found that phylogenetic subgroup D was the most predominant (46 isolates, 35.7%), followed by B2 (44 isolates, 34.1%), A (21 isolates, 16.3%), and B1 (18 isolates, 14.0%). MLST analysis showed 48 sequence types (STs). The most prevalent ST was ST131 (32 isolates, 24.8%), followed by ST393 (23 isolates, 17.8%). While all ST131 isolates belonged to phylogenetic subgroup B2, which is known to be a highly virulent, all ST393 isolates belonged to subgroup D. ST131 and ST393 showed different profiles of virulence factors; papA, papG allele III, and traT genes were significantly more prevalent in ST131 than in ST393 ( p values, Conclusions Based on genotyping, it is suggested that epidemic and virulent ciprofloxacin-resistant E. coli clones such as ST131 and ST393 have disseminated in Korea. However, the diversity of CTX-M genes in ST131 isolates may indicate that ESBL genes have been acquired independently or several ESBL-producing, ciprofloxacin-resistant E. coli clones may have disseminated in the Korean community.

Background The link of low estimated glomerular filtration rate (eGFR) and high proteinuria to cardiovascular disease (CVD) mortality is well known. However, its link to mortality due to other causes is less clear. Methods We studied 367,932 adults (20–93 years old) in the Korean Heart Study (baseline between 1996–2004 and follow-up until 2011) and assessed the associations of creatinine-based eGFR and dipstick proteinuria with mortality due to CVD (1,608 cases), cancer (4,035 cases), and other (non-CVD/non-cancer) causes (3,152 cases) after adjusting for potential confounders. Results Although cancer was overall the most common cause of mortality, in participants with chronic kidney disease (CKD), non-CVD/non-cancer mortality accounted for approximately half of cause of death (47.0%for eGFR

Objectives: To investigate the impact of imipenem resistance on the mortality rate among patients with Acinetobacter bacteraemia. Methods: A retrospective, pairwise-matched (1:1), risk-adjusted (age, Pitt bacteraemia score) cohort study was performed at three tertiary care hospitals in Korea from January 2000 to June 2005. Results: Forty patients with imipenem non-susceptible Acinetobacter bacteraemia (INAB group) and 40 matched subjects (1:1 ratio) with imipenem-susceptible Acinetobacter bacteraemia (ISAB group) were included. Both groups had similar clinical features related to the severity of illness. The 30 day mortality rate was higher in the INAB group (57.5%) than the ISAB group (27.5%) (P = 0.007). The rate of discordant antimicrobial therapy was higher in the INAB group (65.0%) than the ISAB group (20.0%) (P< 0.001). The 30 day mortality rate was higher in the patients with discordant antimicrobial therapy (67.6%) than concordant antimicrobial therapy (23.9%) (P< 0.001). Multivariate analysis showed that age, the Pitt bacteraemia score, immunosuppressive status, and discordant antimicrobial therapy were independent risk factors for 30 day mortality among patients with Acinetobacter bacteraemia (P < 0.05). When discordant antimicrobial therapy was excluded in the multivariate analysis, the imipenem resistance was associated with 30 day mortality (P = 0.005). Conclusions: Imipenem resistance has a significant impact on the mortality rate among patients with Acinetobacter bacteraemia, and this is mainly attributable to the higher rate of discordant antimicrobial therapy.

OBJECTIVES: This retrospective observational study evaluated the distribution of dense breasts by age group among healthy Korean women. METHODS: Participants were women aged 30 years and older who voluntarily underwent screening mammography between January 2007 and December 2011. Women who received the Breast Imaging Reporting and Data System for mammographic density of 3 or 4 were defined as having dense breasts. The proportion of women with dense breasts (PDB, %) was calculated by dividing the number of participants with dense breasts by the total number of participants. RESULTS: Among the 231,058 women who participated, 78.15% were classified as having dense breasts. PDB was highest in the youngest age group (PDB=94.87%) and lowest in the oldest age group. The greatest difference in PDB between adjacent age groups was observed in the group aged 60-64 years. CONCLUSIONS: The results show that the proportion of dense breasts by age group increased in all age groups, except in those aged 35-39 years. These findings suggest an association between the age distribution of dense breasts and trends in breast cancer incidence. Further studies are needed to estimate the change in breast cancer incidence rate by age and the accumulation of fatty breast tissue in Korean women.

Purpose This retrospective cohort study was conducted to estimate the optimal interval for gastric cancer screening in Korean adults with initial negative screening results. Materials and Methods This study consisted of voluntary Korean screenees aged 40 to 69 years who underwent subsequent screening gastroscopies after testing negative in the baseline screening performed between January 2007 and December 2011. A new case was defined as the presence of gastric cancer cells in biopsy specimens obtained upon gastroscopy. The follow-up periods were calculated during the months between the date of baseline screening gastroscopy and positive findings upon subsequent screenings, stratified by sex and age group. The mean sojourn time (MST) for determining the screening interval was estimated using the prevalence/incidence ratio. Results Of the 293,520 voluntary screenees for the gastric cancer screening program, 91,850 (31.29%) underwent subsequent screening gastroscopies between January 2007 and December 2011. The MSTs in men and women were 21.67 months (95% confidence intervals [CI], 17.64 to 26.88 months) and 15.14 months (95% CI, 9.44 to 25.85 months), respectively. Conclusion These findings suggest that the optimal interval for subsequent gastric screening in both men and women is 24 months, supporting the 2-year interval recommended by the nationwide gastric cancer screening program.

The first case of cervical lymphadenitis due to infection by a new Erwinia -like organism is reported. The organism was identified initially as Pantoea sp. by a Vitek 2-based assessment but was finally identified as a member of the genus Erwinia by 16S rRNA gene sequence analysis. The isolate displayed 98.9% 16S rRNA gene sequence similarity to that of E. tasmaniensis and showed phenotypic characteristics that were different from other Erwinia species.

Multilocus sequence typing and in vitro antimicrobial susceptibility testing were performed for three community-onset New Delhi metallo-β-lactamase-1 (NDM-1)-producing Klebsiella pneumoniae isolates from Korea. The genetic structure surrounding the bla NDM-1 gene was determined in bla NDM-1-harbouring plasmids. Three NDM-1-producing K. pneumoniae isolates were found to belong to the same clone (sequence type 340). Each of these isolates showed the same genetic structure surrounding the bla NDM-1 gene. The genes bla NDM-1, ble MBL, trpF and dsbC were flanked by two intact insertion sequences, ISAba125 and IS26, which may promote horizontal gene transfer. The bla NDM-1-harbouring plasmids conferred antimicrobial resistance to carbapenems, cephalosporins, aminoglycosides and aztreonam in transconjugants. It can be speculated that either the entire bla NDM-1-harbouring plasmids or just the part of the plasmid containing the bla NDM-1 gene may have transferred between K. pneumoniae and Escherichia coli. Following the transfer, the isolate disseminated throughout Korea. This study suggests the need for monitoring the dissemination of NDM-1-producing isolates across countries or continents due to their potential transferability via ISAba125- and IS26-associated transposons.

Antimicrobial susceptibility data for all microorganisms isolated from blood culture were collected from 13 institutions in Korea from June to September 2011. Data were compared with our previous studies performed during 2006–2007 and 2008. The prevalence of MRSA in 2011 has rebounded to 63.7% after a slight decrease in 2008. Vancomycin-resistant Enterococcus faecium declined to 24.1%. The resistance rates of Acinetobacter baumannii to imipenem and meropenem increased from 25.4% and 28.8% to 55.4% and 37.5%, respectively. Ciprofloxacin resistance of Escherichia coli has increased from 23.9% to 30.8%. The resistance rate of Klebsiella pneumoniae to ciprofloxacin has increased from 17.7% to 26.5%. Extended spectrum beta-lactamase–producing E. coli and K. pneumoniae have also seen increased levels of resistance, from 8.6% to 18.4% and 13.6% to 28.5%, respectively. An overall increase in antimicrobial resistance among gram-negative pathogens has been observed. Continued surveillance and intervention to slow the propagation of resistance are necessary.

The aim of this study was to more precisely delineate the characteristics and outcomes of bloodstream infections in adult cancer patients. Using a database for nationwide surveillance of bacteremia, we analyzed data related to bacteremia in adult patients with cancer in order to evaluate clinical features and outcomes and to define predictive factors for mortality. Of 1,246 patients, 896 (71.9%) had solid tumors, 328 (26.3%) had hematologic malignancies, and 22 (1.8%) had both. The following conditions were more common in the neutropenic group than in the non-neutropenic group: nosocomial acquisition, hematologic malignancy, corticosteroid use, immunosuppressant use, primary bacteremia, and pneumonia (all P

PURPOSE The purpose of this study was to investigate the experience of examinees who took the first clinical skill examination in Korea. METHODS The data were collected by written survey, telephone, and face-to-face interviews with 46 examinees who took a clinical skills examination test at Jeju National University School of Medicine. Thirty-two questionnaires were valid for analysis. RESULTS Examinees' self-evaluation scores with regard to the level of difficulty of the CPX was 2.83 on average (1 for very easy, 5 for very difficult), and the score on the degree of adequate time for the CPX was 2.69 on average (1 for enough, 5 for very short). Examinees' self-evaluation scores on the level of difficulty of the OSCE was 2.37 on average (1 for very easy, 5 for very difficult), and the score on the degree of adequate time for the OSCE was 2.56 on average (1 for enough, 5 for very short). CONCLUSION We hope that our study provides useful information on practical questions in the development and review of exams and will be used to develop educational content and teaching methods in medical education.

Although several studies have evaluated the association of antimicrobial resistance and mortality in patients with Gram-negative bacteraemia, little is known regarding the impact of antimicrobial resistance on outcome in patients with intra-abdominal infections caused by Gram-negative bacilli (GNB). This study was performed to evaluate the impact of broad-spectrum cephalosporin resistance on outcome in patients with intra-abdominal infections caused by GNB.Data on 365 patients with bacteraemic intra-abdominal infections caused by GNB were obtained from the database of a nationwide surveillance for bacteraemia, and analyzed.Seventy-one of the 365 patients (19.5%) harboured broad-spectrum cephalosporin-resistant infections. When compared with patients with susceptible infections, the group of patients with resistant infections had a lower treatment success rate at 7 days after the initiation of antimicrobial therapy (73.2% vs 85.0%, p = 0.023). However, the 30-day mortality rate for the resistant group was not significantly higher than for the susceptible group (16.9% vs 10.2%, p = 0.112). Multivariable analysis showed that severe sepsis was the most important risk factor associated with mortality (odds ratio 4.91, 95% confidence interval 2.26-10.63), along with underlying liver disease, nosocomial acquisition, underlying solid tumour, and higher Pitt bacteraemia score (all p0.05). Antimicrobial resistance and inappropriate initial antimicrobial therapy were not found to be associated with mortality.Our data suggest that antimicrobial resistance and inappropriate initial antimicrobial therapy may not be significant determinants for the prognosis in intra-abdominal infections caused by GNB, for which drainage or decompression procedures of intra-abdominal sources are often necessary.

This study was performed to determine clinical predictors for enterococcal bacteraemia among hospitalized patients with suspected sepsis of abdominal origin. Among patients with bacteraemic intra-abdominal infections, 50 patients with enterococcal bacteraemia were compared with 618 patients with Gram-negative bacteraemia. Nosocomial acquisition and recent operation were found to be significantly associated with enterococcal bacteraemia, along with haematological malignancy, percutaneous trans-hepatic biliary drainage, and solid tumour (p < 0.05 for all).

Multicenter data on in vitro susceptibility of Candida bloodstream isolates to echinocandin antifungal agents is still lacking in South Korea. We performed a prospective multicenter study to determine the species distribution of Candida bloodstream isolates and their susceptibility to five antifungal agents, including caspofungin and micafungin. A total of 639 isolates were collected from 20 tertiary hospitals between September 2006 and August 2007. Antifungal susceptibilities were determined through the use of the CLSI broth microdilution method M27-A3. The overall species distribution was as follows; Candida albicans (38%), Candida parapsilosis (26%), Candia tropicalis (20%), Candida glabrata (11%), and miscellaneous Candida species (5%). Although C. parapsilosis and miscellaneous Candida species were less susceptible to both echinocandins, all 639 isolates were susceptible to both caspofungin and micafungin (MIC,or= 2 microg/ml). Nearly all isolates (99.7%) had a MICor= 1 microg/ml to amphotericin B. Resistance to fluconazole and voriconazole was found in 0.8% and 0.3%, respectively, among all Candida isolates, with C. glabrata and C. krusei isolates displaying the greatest level of resistance. This is the largest multicenter candidemia study conducted in South Korea and shows that non-C. albicans Candida species, including C. parapsilosis, constitutes over 60% of all Candida species isolates recovered from the bloodstream. In addition, the rates of resistance to all five antifungals, including two echinocandins, are still low among bloodstream isolates in South Korea.

The purpose of this study was to identify risk factors for extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli amongst community-onset bacteraemia and to evaluate treatment outcomes. From the database of a nationwide surveillance programme for bacteraemia, data from patients with community-onset E. coli bacteraemia were analysed. Patients with ESBL-producing E. coli bacteraemia were compared with those with non-ESBL-producing bacteraemia. The overall proportion of ESBL-producers was 9.5% (82/865) amongst community-onset E. coli bacteraemia cases. Healthcare-associated infection, underlying liver disease and primary bacteraemia were significant independent factors associated with ESBL-producing E. coli bacteraemia (P0.05). There was a trend toward mortality being higher in the ESBL group compared with the non-ESBL group (15.0% vs. 7.6%; P=0.096). ESBL production was found to be an independent factor associated with mortality after adjusting for confounding variables (odds ratio=2.99, 95% confidence interval 1.01-8.84; P=0.048), along with severe sepsis, higher Pitt bacteraemia score, primary bacteraemia, pneumonia and underlying liver disease (P0.05). ESBL-producing E. coli is a significant cause of bacteraemia, even in patients with community-onset infections, predicting higher mortality, particularly in patients with primary bacteraemia, underlying liver disease or healthcare-associated infection.

Background Although hospital-acquired infections presumably may have a poorer prognosis than community-onset infections because of unanticipated antimicrobial resistance, little data are available on the clinical and microbiological characteristics of hospital-acquired versus community-onset urinary tract–related bacteremia cases. Methods Data were collected from a nationwide database of surveillance for bacteremia. Data from patients with hospital-acquired urinary tract–related bacteremia were compared with those with community-onset bacteremia. Results Of 398 patients with urinary tract–related bacteremia, 71 (17.8%) had hospital-acquired infection, and the remaining 327 (82.2%) had community-onset infection. Although Escherichia coli was the most common isolate identified, pathogens other than E coli were more frequently isolated in hospital-acquired infections than in community-onset infections (46.5% vs 19.3%). Among E coli isolates causing hospital-acquired infections, 26.3% (10 of 38) were resistant to extended-spectrum cephalosporins (ESCs), whereas among E coli isolates causing community-onset infections, only 6.1% (16 of 264) were ESC-resistant. Hospital-acquired infection had a significantly higher mortality rate than community-onset infection (21.1% [15 of 71] vs 8.3% [27 of 327]; P = .004). Multivariate analysis identified nosocomial acquisition as a significant independent risk factor for mortality, along with severe sepsis, underlying solid tumor, ESC resistance, and high Pitt bacteremia score (all P Conclusion Hospital-acquired urinary tract–related bacteremia has a poorer prognosis than community-onset bacteremia. The ESC-resistant nature of gram-negative bacilli, which may be more common in nosocomial isolates than in community isolates, adversely affects the outcome of urinary tract–related bacteremia.

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.

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.

We report an unusual case of Plasmodium vivax malaria that occurred in a 22-year-old ankylosing spondylitis patient after initiating adalimumab therapy. P. falciparum malaria was initially included as a possible differential diagnosis due to hyperparasitemia and similar features in the peripheral blood smear. The patient was successfully treated with conventional therapy for P. vivax malaria.

Recent changes in healthcare systems have changed the epidemiologic paradigms in many infectious fields including bloodstream infection (BSI). We compared clinical characteristics of community-acquired (CA), hospital-acquired (HA), and healthcare-associated (HCA) BSI. We performed a prospective nationwide multicenter surveillance study from 9 university hospitals in Korea. Total 1,605 blood isolates were collected from 2006 to 2007, and 1,144 isolates were considered true pathogens. HA-BSI accounted for 48.8%, CA-BSI for 33.2%, and HCA-BSI for 18.0%. HA-BSI and HCA-BSI were more likely to have severe comorbidities. Escherichia coli was the most common isolate in CA-BSI (47.1%) and HCA-BSI (27.2%). In contrast, Staphylococcus aureus (15.2%), coagulase-negative Staphylococcus (15.1%) were the common isolates in HA-BSI. The rate of appropriate empiric antimicrobial therapy was the highest in CA-BSI (89.0%) followed by HCA-BSI (76.4%), and HA-BSI (75.0%). The 30-day mortality rate was the highest in HA-BSI (23.0%) followed by HCA-BSI (18.4%), and CA-BSI (10.2%). High Pitt score and inappropriate empirical antibiotic therapy were the independent risk factors for mortality by multivariate analysis. In conclusion, the present data suggest that clinical features, outcome, and microbiologic features of causative pathogens vary by origin of BSI. Especially, HCA-BSI shows unique clinical characteristics, which should be considered a distinct category for more appropriate antibiotic treatment.

Systemic lupus erythematosus (SLE) is a multisystemic inflammatory autoimmune disease caused by various autoantibodies and immune complexes. SLE and antiphospholipid antibodies are associated with thrombotic manifestations. However, renal artery thrombosis which causes renal artery occlusion is uncommon even in SLE patients with antiphospholipid antibodies. A 27-year-old woman with SLE suddenly developed left flank pain and generalized edema. From the laboratory workup, the woman was negative for antiphospholipid antibody and nephroticrange proteinuria was detected. Computed tomography revealed renal artery thromboembolism and multiple renal infarctions with parenchymal perfusion defects in the left kidney. Renal biopsy showed WHO classification III and V lupus nephritis. Left flank pain, generalized edema and proteinuria were resolved and the thromboembolism resolved itself after a high dose of steroid and anticoagulation therapy. In SLE patients, sudden onset of unexplained flank pain is considered as a possible symptom of renal vessel thromboembolism even if the antiphospholipid antibody is negative.

(36.3%) was the most common, followed by M. pneumoniae (23.0%), C. pneumoniae (17.0%), S. aureus (9.6%) and P. aeruginosa (5.9%). The initial treatment failure (23.8%) was related to the isolation of polymicrobial pathogens, elevated inflammatory markers, and the presence of pleural effusion. Among the 30 isolates of S. pneumoniae, 16 (53.3%) were not susceptible to penicillin, and 19 isolates (63.3%) to erythromycin and clarithromycin. However, 29 isolates (96.7%) were susceptible to levofloxacin and ceftriaxone. Conclusion: S. pneumoniae, M. pneumoniae, S. aureus, and P. aeruginosa are frequent etiologic agents of adult CAP in Jeju, Korea. The clinical characteristics and antibiotic resistance should be considered when determining the initial empirical antimicrobial choice. Respiratory quinolone or ceftriaxone is recommended as an empirical antimicrobiotic in the treatment of adult CAP in Jeju, Korea.

Delftia acidovorans is a gram-negative motile rod found ubiquitously in soil and in water. Confirmed isolation from clinical infections is rare, and has been documented mostly in immunocompromised patients or those with indwelling catheters. A 53-year-old man was referred for the evaluation of a huge mass-like lesion found incidentally by chest X-ray. The lesion occupied more than half of the right lung and was diagnosed as a large loculated pleural effusion by CT scan. Bloody pus was drained through a percutaneous catheter, and D. acidovorans , identified by the Vitek GN card and confirmed by amplification of 16S ribosomal RNA and sequencing analysis, was isolated repeatedly from the drained pus. The patient was treated with imipenem/cilastatin to which the organism was sensitive. This is a rare report of chronic empyema associated with D. acidovorans in the respiratory system of an immunocompetent patient.

Public Health Reports / November–December 2009 / Volume 124 883 This article by Choi et al. describes the findings from 19 tertiary-care teaching hospitals in South Korea. At first, the finding that infectious diseases are attributed to 29% of all in-hospital deaths seems unexpected. Then we realize that the numbers, while surprising, are not unusual. In the United States, hospital-acquired infections are a countrywide problem. It has been estimated that each year nearly two million patients get an infection while being treated in our nation’s hospitals, and almost 100,000 of them die in the U.S. The Centers for Disease Control and Prevention estimates the cost of hospital-acquired infections to be as high as $27.5 billion each year.1 The findings in this study and elsewhere bring to light the fact that even the “most developed” countries, such as South Korea, the United Kingdom,2 and the United States, still face a constant and, in some cases, increasing threat from infection-related mortality in hospital settings. It is also interesting to note that pneumonia and septicemia remain the most common causes of death. The sentinel hospital-based surveillance system is an important step toward developing and maintaining a useful monitoring system to control routine and extraordinary infectious diseases. Other studies in the literature set up a standardized methodology for the mining and investigation of infection control surveillance.3 This article, however, is the first to evaluate the proportions of infectious diseases among all in-hospital mortality cases as either the direct or underlying cause of death and investigate the description of infectious causes of in-hospital death in South Korea.