Chisook Moon

Risk factors and treatment outcomes of community-onset bacteraemia caused by extended-spectrum β-lactamase-producing Escherichia coli

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 (P<0.05). 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 (P<0.05). 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.

Anti-asthmatic effect of marine red alga (Laurencia undulata) polyphenolic extracts in a murine model of asthma.

The aim of the present work is focused on protective effects of an edible red alga, Laurencia undulata ethanolic (EtOH) extracts (LU) containing a large amount of polyphenols against OVA-induced murine allergic airway reactions using in vivo histological and cytokine assay. Mice sensitized and challenged with ovalbumin (OVA) showed typical asthmatic reactions as follows: an increase in the number of eosinophil in bronchoalveolar lavage fluid; a marked influx of inflammatory cells into the lung around blood vessels and airways, and airway luminal narrowing; the development of airway hyperresponsiveness; the detection of TNF-alpha and Th2 cytokines, such as IL-4 and IL-5 in the bronchoalveolar lavage (BAL) fluid; and detection of allergen-specific IgE in the serum. The successive intraperitoneal administration of LU before the last airway OVA-challenge resulted in a significant inhibition of all asthmatic reactions. These results suggest that L. undulata polyphenolic extracts possess therapeutic potential for combating bronchial asthma associated with allergic diseases.

Genotypic Diversity of Methicillin-Resistant Staphylococcus aureus Isolates in Korean Hospitals

ABSTRACT Ninety-six methicillin-resistant Staphylococcus aureus (MRSA) isolates from eight Korean hospitals were analyzed by multilocus sequence typing, SCCmec typing, and spa typing. The predominant genotype was ST5-MRSA-II of clonal complex 5, which was found in 36 isolates from six hospitals, but ST239-MRSA-III was also common. Overall, results showed a notable genotypic diversity of MRSA strains circulating in Korean hospitals.

Cilostazol protects mice against endotoxin shock and attenuates LPS-induced cytokine expression in RAW 264.7 macrophages via MAPK inhibition and NF-κB inactivation: Not involved in cAMP mechanisms

Cilostazol, a phosphodiesterase 3 inhibitor, is a platelet aggregation inhibitor and vasodilator that is useful for treating intermittent claudication. Experimental studies have shown that cilostazol has potent anti-inflammatory effects. In the present study, we examined the effect of cilostazol on lipopolysaccharide (LPS)-induced inflammatory cytokines in macrophages and endotoxin shock in mice. Our results indicate that cilostazol inhibits LPS-stimulated up-regulation of pro-inflammatory cytokines in a concentration-dependent manner without appreciable cytotoxicity in RAW 264.7 cells. Cilostazol did not enhance intracellular cyclic AMP (cAMP) levels. To further elucidate the mechanism responsible for the inhibition of production of pro-inflammatory mediators by cilostazol, we examined the effect of cilostazol on LPS-stimulated nuclear factor-kappaB (NF-kappaB) activation and phosphorylation of mitogen-activated protein kinases (MAPK). Our results clearly indicated that cilostazol treatment reduced on of MAPK phosphorylation and NF-kappaB activity, and that the inhibitory effect of cilostazol is independent of the cAMP pathway. In an animal model, cilostazol protected c57BL/6 mice from LPS-induced endotoxin shock, possibly through inhibition of the production of pro-inflammatory cytokines. In conclusion, cilostazol inhibits LPS-stimulated production of pro-inflammatory cytokines and protects mice from endotoxin shock, suggesting that cilostazol may be a novel therapeutic agent for the prevention of various inflammatory diseases.

Adverse events associated with the 2009 H1N1 influenza vaccination and the vaccination coverage rate in health care workers

We prospectively examined the 2009 H1N1 influenza vaccination coverage rate and the adverse events related to the monovalent vaccine in Korean health care workers. The H1N1 vaccination coverage rate was 91.7%. There were no significant adverse events discouraging the vaccination.

Factors associated with ciprofloxacin- and cefotaxime-resistant Escherichia coli in women with acute pyelonephritis in the emergency department

BACKGROUND High rates of antimicrobial resistance in Escherichia coli isolated from patients with urinary tract infections have been reported worldwide. The aim of this study was to identify risk factors for resistance to ciprofloxacin (CIP) and cefotaxime (CTX) in E. coli isolated from patients with acute pyelonephritis (APN). METHODS We prospectively identified women over 18 y of age who visited the emergency department of one of 10 hospitals with APN and whose urine culture grew E. coli. The study was conducted from April 16 to June 10, 2012. RESULTS Of the 229 patients identified, 173 (75.5%) had community-associated (CA) infections and 56 (24.5%) had healthcare-associated (HCA) infections. Sixty-seven isolates (29.3%) were resistant to CIP, 45 (19.7%) to CTX, and 29 (12.7%) to both CIP and CTX. Multivariate analyses revealed that hematologic disease, chronic kidney disease, a bed-ridden state, indwelling urinary catheter, antibiotic treatment in the preceding 3 months, and isolation of CIP-resistant E. coli in the urine within the preceding 3 months, were significantly associated with resistance to both CIP and CTX. CONCLUSIONS Chronic conditions and healthcare-associated factors were related to resistance to both fluoroquinolones and third-generation cephalosporins in women with APN. Continued and vigilant surveillance is necessary to monitor the dissemination of antimicrobial resistance in uropathogens.

Impact of a national hospital evaluation program using clinical performance indicators on the use of surgical antibiotic prophylaxis in Korea

OBJECTIVES Clinical performance measurement in surgical antibiotic prophylaxis (SAP) was implemented as part of a national hospital evaluation program (NHEP) in Korea in 2007. This study investigated changes in SAP quality before and after the implementation of clinical performance measurement. METHODS The medical records of patients who underwent three types of surgery that were included for assessment in the NHEP (NHEP surgery) - arthroplasty, gastrectomy, and hysterectomy - and two other types of non-NHEP assessment surgery - craniotomy and spine surgery (non-NHEP surgery) - at six hospitals, from August to October in 2006-2008, were retrospectively reviewed. Three clinical indicators of SAP (antibiotic selection, timing of administration of the first dose, and duration) and the development of surgical site infections (SSIs) were compared before and after implementation. RESULTS A total of 1949 patients were enrolled: 356 arthroplasty, 273 gastrectomy, 615 hysterectomy, 168 craniotomy, and 537 spinal surgery. There were no significant changes in age, gender, wound class, or ASA score for each surgery during the study period. From 2007, SAP quality was significantly improved in NHEP surgery for the three clinical indicators. The timing of administration of the first dose was most markedly improved. SAP quality was also improved in non-NHEP surgery, but not as much as in NHEP surgery. Changes in the SSI rates for each surgery were not significant. CONCLUSIONS Hospital evaluation using clinical performance indicators can considerably improve the use of SAP. Further studies are warranted to investigate whether this hospital evaluation will decrease the development of SSIs.

Severity predictors in eschar-positive scrub typhus and role of serum osteopontin.

We prospectively evaluated severity predictors in terms of host, microorganism, and treatment factors in 153 eschar-positive scrub typhus patients. Severity was assessed with the Acute Physiology and Chronic Health Evaluation (APACHE) II score (< 10 versus ≥ 10) and predefined criteria of severe complications. Genotypes of Orientia tsutsugamushi were determined. Independent risk factors for severity (APACHE II score ≥ 10) were old age, diabetes mellitus, serum osteopontin > 100 ng/mL, and a group of underlying diseases (congestive heart failure, cerebrovascular disease, chronic liver disease, bronchial asthma, and chronic obstructive lung diseases). Anemia (≤ 10 g/dL) and C-reactive protein > 10 mg/dL were indicators of current severity. Neither the delay in antibiotics administration nor strain types (Boryong, Taguchi, or Kanda/Kawasaki) contributed to the severity. The risk factors for severe complications were similar. Serum osteopontin > 100 ng/mL had a negative predictive value of 96% for severe complications. This marker can be used to rule out severe disease status.

Antigenic Drift of Orientia tsutsugamushi in South Korea as Identified by the Sequence Analysis of a 56-kDa Protein-Encoding Gene

This study was performed to determine the nationwide antigenic diversity of Orientia tsutsugamushi in South Korea. Sequence analysis was performed around variable domains I and II of a 56-kDa protein-encoding gene. We used eschar to overcome the disadvantages of conventional serotyping. The serological passive hemagglutination assay (PHA) was assessed based on the genotyping results. We analyzed 153 isolates from scrub typhus patients in major endemic areas and found that Boryong was the major strain (68.6%). New strains were also identified: Taguchi (19.6%), Kanda/Kawasaki (9.2%), and UAP7 (1.3%). PHA yielded significantly fewer positive results among Kawasaki strains (P < 0.001), which are not included in the PHA antigen panel. In South Korea, Boryong was still the predominant strain, but the sequence analysis identified new changes in minor strains (30.1%). This antigenic drift had a negative effect on the PHA results. Periodic surveillance of the contemporary strains using sequence analysis is needed.

Risk factors for hospital-acquired pneumonia caused by carbapenem-resistant Gram-negative bacteria in critically ill patients: a multicenter study in Korea

We performed a case-control study to identify risk factors of carbapenem-resistant Gram-negative bacteria (CRGNB) as an increasing cause of hospital-acquired pneumonia (HAP). The study included critically ill adult patients with HAP whose microbial etiology was identified at eight tertiary centers in Korea between June 2008 and December 2009. Eighty two patients with 86 isolates of CRGNB (62 Acinetobacter baumannii, 14 Pseudomonas aeruginosa, and 10 Stenotrophomonas maltophilia) were included in the case group, and 122 patients with carbapenem-susceptible Gram-negative bacteria were included in the control group. Diabetes mellitus (adjusted odds ratio [aOR] 2.82, 95% confidence interval [95% CI] 1.25-6.38), radiologic score ≥5 (aOR 4.56, 95% CI 2.36-8.81), prior fluoroquinolone (aOR 2.39. 95% CI = 1.07-5.35), or carbapenem usage (aOR 2.82, 95% CI 1.75-17.83) were found to be independent risk factors. Fluoroquinolone and carbapenem should be cautiously used to avoid HAP caused by CRGNB.