OBJECTIVE: To investigate the phylogenetics and prevalence of bloodstream infections with ST131, the antimicrobial resistance profiles of the pathogens, and the clinical features. METHODS: Non-duplicate isolates were collected from 144 patients with bloodstream infections in our hospital between January and December, 2016.The phylogenetic groups of the isolates were analyzed using multiplex PCR, and O serotyping of ST131 strains was performed by allele-specific PCR.The clinical characteristics of the 144 patients were analyzed to define the differences in the clinical features between patients with ST131 infection and those with non-ST131 infection.Antibiotic susceptibility of the isolates was determined using the Vitek 2 compact system. RESULTS: The phylogenetic group analysis showed a domination by group B2 (41.0%[59/144]), followed by group F, group B1 and group E, which accounted for 16.7%(24/144), 13.9%(20/144), and 13.2% (19/144), respectively.Nine strains (6.3%) of were identified to be ST131 strains, among which 8 were O25b-B2-ST131 strains and 1 was O16-B2-ST131 strain.Of the 9 cases of ST131 infection, 7(77.8%) were found to occur in a nosocomial setting.The demographic characteristics and clinical features of the ST131-infected patients were similar to those of non-ST131-infected patients.ST131 strains were sensitive to piperacillin/tazobactam, imipenem, ertapenem, and amikacin, but showed high resistance rates to cefazolin, ceftriaxone, ciprofloxacin, levofloxacin, gentamicin, and trimethoprim/ sulfamethoxazole (all over 50%).The positivity rate of ESBLs in the ST131 strains was 77.8%, and the multidrug resistance rate reached 88.9%, which was higher than that of non-ST131 isolates, but the difference was not statistically significant. CONCLUSIONS The most common phylogenetic groups of isolates from patients with bloodstream infections are group B2 and F, and the positivity rate of ST131 is low.We for the first time detected O16-ST131 in patients with blood-borne infections in China.The clinical features of ST131-infected patients are similar to those of non-ST131-infected patients.The positivity rate of ESBLs and the multidrug resistance rate are high in ST131 strains, which may raise concerns in the future.
Anti-Bacterial Agents ; therapeutic use ; Bacteremia ; drug therapy ; epidemiology ; microbiology ; China ; Drug Resistance, Bacterial ; Escherichia coli ; classification ; drug effects ; genetics ; Escherichia coli Infections ; drug therapy ; epidemiology ; microbiology ; Genotype ; Humans ; Microbial Sensitivity Tests ; Molecular Epidemiology ; Phylogeny ; Species Specificity

Nontuberculous mycobacteria (NTM) are ubiquitous organisms; their isolation from clinical specimens does not always indicate clinical disease. The incidence of NTM lung diseases has been increasing worldwide. Although the geographic diversity of NTM species is well known, Mycobacterium avium complex (MAC), M. abscessus complex (MABC), and M. kansasii are the most commonly encountered and important etiologic organisms. Two distinct types of NTM lung diseases have been reported, namely fibrocavitary and nodular bronchiectatic forms. For laboratory diagnosis of NTM lung diseases, both liquid and solid media cultures and species-level identification are strongly recommended to enhance growth detection and determine the clinical relevance of isolates. Treatment for NTM lung diseases consists of a multidrug regimen and a long course of therapy, lasting more than 12 months after negative sputum conversion. For MAC lung disease, several new macrolide-based regimens are now recommended. For nodular bronchiectatic forms of MAC lung diseases, an intermittent three-time-weekly regimen produces outcomes similar to those of daily therapy. Treatment of MABC lung disease is very difficult, requiring long-term use of parenteral agents in combination with new macrolides. Treatment outcomes are much better for M. massiliense lung disease than for M. abscessus lung disease. Thus, precise identification of species in MABC infection is needed for the prediction of antibiotic response. Likewise, increased efforts to improve treatment outcomes and develop new agents for NTM lung disease are needed.
Anti-Bacterial Agents/therapeutic use ; Drug Therapy, Combination ; Humans ; Lung Diseases/*diagnosis/drug therapy/epidemiology ; Mycobacterium Infections, Nontuberculous/*diagnosis/drug therapy/epidemiology ; Mycobacterium avium Complex/isolation & purification ; Sputum/microbiology

BACKGROUND: We determined the epidemiological characteristics of erythromycin (EM)-resistant Streptococcus pyogenes (group A streptococci, GAS) strains isolated from Korea and Japan, using emm genotyping and multilocus sequence typing (MLST). METHODS: Clinical isolates of GAS had been collected from 1992 to 2012 in Korea and from 2004 to 2009 in Japan. EM resistance was determined by the microdilution method, and resistance genotypes were assessed by PCR. The emm genotyping and MLST were performed by DNA sequencing. RESULTS: The emm genotypes and sequence types (STs) were concordant in 143 (85.1%) of 168 EM-resistant GAS strains from Korea. ST36/emm12 (35.1%), ST52/emm28 (22.6%), and ST49/emm75 (16.1%) were the most common types. Most of the ST36 (93.9%) and ST52 (95.8%) strains harbored erm(B), whereas strains ST49, ST42, and ST15 contained mef(A). The concordance between emm genotypes and STs was 41 (93.2%) among 44 EM-resistant GAS strains from Japan. ST36/emm12 (34.1%), ST49/emm75 (18.2%), and ST28/emm1 (15.9%) were the major types. ST36 isolates harbored either erm(B) (56.3%) or mef(A) (37.5%), whereas isolates ST28, ST49, and ST38 carried only mef(A). The proportion of erm(B) and mef(A) was 66.1% and 33.3% in Korea and 22.7% and 68.2% in Japan, respectively. CONCLUSIONS: The common STs in Korea and Japan were ST36 and ST49, whereas ST52 was present only in Korea and ST28 only in Japan. Genotype erm(B) was predominant in Korea, whereas mef(A) was frequent in Japan. There were differences between Korea and Japan regarding the frequencies of emm genotypes, STs, and EM resistance genes among the EM-resistant GAS.
Anti-Bacterial Agents/*pharmacology/therapeutic use ; Bacterial Proteins/*genetics ; Bacterial Typing Techniques ; *Drug Resistance, Bacterial ; Epidemiologic Studies ; Erythromycin/*pharmacology/therapeutic use ; Genotype ; Humans ; Japan/epidemiology ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Republic of Korea/epidemiology ; Streptococcal Infections/drug therapy/*microbiology ; Streptococcus pyogenes/drug effects/*genetics/isolation & purification

Urinary tract infection (UTI) is one of the most common complications after radical cystectomy and orthotopic neobladder reconstruction. This study investigated the incidence and implicated pathogen of febrile UTI after ileal neobladder reconstruction and identify clinical and urodynamic parameters associated with febrile UTI. From January 2001 to May 2015, 236 patients who underwent radical cystectomy and ileal neobladder were included in this study. Fifty-five episodes of febrile UTI were identified in 46 patients (19.4%). The probability of febrile UTI was 17.6% and 19.8% at 6 months and 24 months after surgery, respectively. While, Escherichia coli was the most common implicated pathogen (22/55, 40.0%), Enterococcus spp. were the most common pathogen during the first month after surgery (18/33, 54.5%). In multivariate logistic regression analysis, ureteral stricture was an independent risk factor associated with febrile UTI (OR 5.93, P = 0.023). However, ureteral stricture accounted for only 6 episodes (10.9%, 6/55) of febrile UTI. Most episodes of febrile UTI occurred within 6 months after surgery. Thus, to identify risk factors associated with febrile UTI in the initial postoperative period, we assessed videourodynamics within 6 months after surgery in 38 patients. On videourodyamic examination, vesicoureteral reflux (VUR) was identified in 16 patients (42.1%). The rate of VUR presence in patients who had febrile UTI was not significantly different from those in patients without febrile UTI (50% vs. 39.3%, P = 0.556). Patients with febrile UTI had significantly larger residual urine volume (212.0 ± 193.7 vs. 90.5 ± 148.2, P = 0.048) than those without. E. coli and Enterococcus spp. are common pathogens and ureteral stricture and residual urine are risk factors for UTI after ileal neobladder reconstruction.
Aged ; Anti-Bacterial Agents/therapeutic use ; Cystectomy/adverse effects ; Enterococcus/isolation & purification ; Escherichia coli/isolation & purification ; Female ; Humans ; Ileum/*surgery ; Incidence ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Postoperative Complications ; Reconstructive Surgical Procedures ; Retrospective Studies ; Risk Factors ; Urinary Bladder Neoplasms/*surgery ; Urinary Tract Infections/drug therapy/*epidemiology/etiology/microbiology ; Urodynamics

The efficacy of seven-day clarithromycin-based standard triple therapy (STT) for Helicobacter pylori has decreased in Korea over the past decade. The aim of this meta-analysis was to clarify the efficacy of first-line and second-line therapies in Korea. This systematic review will provide an overview of H. pylori eradication and present new therapeutic strategies used in Korea. An extensive search of the literature concerning STT, sequential therapy (SET), concomitant therapy (CT), bismuth-containing quadruple therapy (BCQT) and various other therapies used in Korea was performed. All selected studies were randomized controlled trials (RCTs). Eighteen RCTs were eligible for systematic review. The alternative regimens comparing seven-day STT as a first-line therapy include SET, CT, levofloxacin-based therapy (LBT), BCQT, and STT with prolonged duration. The results of the meta-analysis suggest that SET is superior to seven-day STT. The overall eradication rate by intention to treat (ITT) analysis was 69.8% for STT and 79.7% for SET. The overall eradication rate by per-protocol (PP) analysis was 77.0% for STT and 85.0% for SET. The odds ratios for the ITT and PP eradication rate were 0.57 (95% confidence interval [CI], 0.43 to 0.74) and 0.52 (95% CI, 0.35 to 0.76), respectively. In the subgroup analysis, however, there were no significant differences between SET and STT with prolonged durations. Alternative regimens to seven-day BCQT as second-line therapy include LBT, moxifloxacin-based therapy and 14-day BCQT. The eradication rates of these alternative regimens were not superior to that of the conventional treatment. SET is superior to seven-day STT but not to STT with prolonged duration.
Anti-Bacterial Agents/*administration & dosage/classification ; Evidence-Based Medicine ; Female ; Helicobacter Infections/*drug therapy/*epidemiology/microbiology ; Helicobacter pylori/*drug effects ; Humans ; Male ; Practice Patterns, Physicians'/*statistics & numerical data ; Prevalence ; Republic of Korea/epidemiology ; Risk Assessment ; Treatment Outcome

Infective endocarditis (IE) has been increasingly diagnosed in patients without previously detected predisposing heart disease, but its clinical features have yet to be fully determined. A recent single-center study including echocardiographic images and surgical findings investigated the incidence of undiagnosed, clinically silent valvular or congenital heart diseases and healthcare-associated infective endocarditis (HAIE). The study confirmed that a large proportion of patients with IE have no previous history of heart disease. Analysis of underlying disease in these patients showed that undetected mitral valve prolapse was the most common disease, followed by an apparently structurally normal valve. The patients who developed IE of apparently structurally normal valves had different clinical characteristics and worse outcomes. IE involving a structurally normal valve was associated with both nosocomial and non-nosocomial HAIE, whereas community-acquired IE was more frequent than HAIE. The pathophysiologic mechanism involving the development of non-HAIE or community-acquired IE due to predominantly staphylococcal infection in an apparently structurally normal valve is not yet clearly understood. Structurally normal valves are not necessarily free of regurgitation or abnormal turbulence and, given the dynamic nature and fluctuating hemodynamic effects of conditions such as poorly controlled hypertension, end-stage renal disease, and sleep apnea, further investigation is necessary to evaluate the potential role of these diseases in the development of IE. An apparently normal-looking valve is associated with IE development in patients without previously recognized predisposing heart disease, warranting repartition of at-risk groups to achieve better clinical outcomes.
Adult ; Aged ; Community-Acquired Infections/diagnosis/*epidemiology/microbiology/physiopathology/therapy ; Cross Infection/diagnosis/*epidemiology/microbiology/physiopathology/therapy ; Echocardiography, Doppler, Color ; Endocarditis, Bacterial/diagnosis/*epidemiology/microbiology/physiopathology/therapy ; Female ; Heart Valves/*microbiology/physiopathology/ultrasonography ; Humans ; Incidence ; Male ; Middle Aged ; Predictive Value of Tests ; Prognosis ; Risk Factors

PURPOSE: Over the last 30 years, Serratia marcescens (S. marcescens) has emerged as an important pathogen, and a common cause of nosocomial infections. The aim of this study was to identify risk factors associated with mortality in patients with S. marcescens bacteremia. MATERIALS AND METHODS: We performed a retrospective cohort study of 98 patients who had one or more blood cultures positive for S. marcescens between January 2006 and December 2012 in a tertiary care hospital in Seoul, South Korea. Multiple risk factors were compared with association with 28-day all-cause mortality. RESULTS: The 28-day mortality was 22.4% (22/98 episodes). In a univariate analysis, the onset of bacteremia during the intensive care unit stay (p=0.020), serum albumin level (p=0.011), serum C-reactive protein level (p=0.041), presence of indwelling urinary catheter (p=0.023), and Sequential Oran Failure Assessment (SOFA) score at the onset of bacteremia (p<0.001) were significantly different between patients in the fatal and non-fatal groups. In a multivariate analysis, lower serum albumin level and an elevated SOFA score were independently associated with 28-day mortality [adjusted odds ratio (OR) 0.206, 95% confidential interval (CI) 0.044-0.960, p=0.040, and adjusted OR 1.474, 95% CI 1.200-1.810, p<0.001, respectively]. CONCLUSION: Lower serum albumin level and an elevated SOFA score were significantly associated with adverse outcomes in patients with S. marcescens bacteremia.
Adult ; Aged ; Aged, 80 and over ; Anti-Bacterial Agents/therapeutic use ; Bacteremia/drug therapy/microbiology/*mortality ; Cross Infection/mortality ; Female ; Humans ; Intensive Care Units ; Male ; Middle Aged ; Multiple Organ Failure ; Republic of Korea/epidemiology ; Retrospective Studies ; Risk Factors ; Serratia Infections/diagnosis/drug therapy/*mortality ; Serratia marcescens/drug effects/*isolation & purification ; Severity of Illness Index ; Survival Rate ; Time Factors ; Treatment Outcome

INTRODUCTIONTreatment of acute lymphoblastic leukaemia (ALL) using intensive chemotherapy has resulted in high cure rates but also substantial morbidity. Infective complications represent a significant proportion of treatment-related toxicity. The objective of this study was to describe the microbiological aetiology and clinical outcome of episodes of chemotherapy-induced febrile neutropaenia in a cohort of children treated for ALL at our institution.

MATERIALS AND METHODSPatients with ALL were treated with either the HKSGALL93 or the Malaysia-Singapore (Ma-Spore) 2003 chemotherapy protocols. The records of 197 patients who completed the intensive phase of treatment, defined as the period of treatment from induction, central nervous system (CNS)-directed therapy to reinduction from June 2000 to January 2010 were retrospectively reviewed.

RESULTSThere were a total of 587 episodes of febrile neutropaenia in 197 patients, translating to an overall rate of 2.98 episodes per patient. A causative pathogen was isolated in 22.7% of episodes. An equal proportion of Gram-positive bacteria (36.4%) and Gram-negative bacteria (36.4%) were most frequently isolated followed by viral pathogens (17.4%), fungal pathogens (8.4%) and other bacteria (1.2%). Fungal organisms accounted for a higher proportion of clinically severe episodes of febrile neutropaenia requiring admission to the high-dependency or intensive care unit (23.1%). The overall mortality rate from all episodes was 1.5%.

CONCLUSIONFebrile neutropaenia continues to be of concern in ALL patients undergoing intensive chemotherapy. The majority of episodes will not have an identifiable causative organism. Gram-positive bacteria and Gram-negative bacteria were the most common causative pathogens identified. With appropriate antimicrobial therapy and supportive management, the overall risk of mortality from febrile neutropaenia is extremely low.

Candidiasis ; epidemiology ; Chemotherapy-Induced Febrile Neutropenia ; epidemiology ; microbiology ; Child ; Cohort Studies ; Escherichia coli Infections ; epidemiology ; Gram-Negative Bacterial Infections ; epidemiology ; Gram-Positive Bacterial Infections ; epidemiology ; Humans ; Influenza, Human ; epidemiology ; Klebsiella Infections ; epidemiology ; Mycoses ; epidemiology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; Pseudomonas Infections ; epidemiology ; Retrospective Studies ; Singapore ; epidemiology ; Staphylococcal Infections ; epidemiology ; Virus Diseases ; epidemiology

Most gastric cancers are caused by infection with the common human bacterial pathogen, Helicobacter pylori. It is now accepted that gastric cancer can be prevented and virtually eliminated by H. pylori eradication and this knowledge was responsible for country-wide H. pylori eradication combined with secondary cancer prevention for those with residual risk that was introduced in Japan in 2013. Korea is a high H. pylori prevalence and high gastric cancer incidence country and a good candidate for a gastric cancer elimination program. The presence of an H. pylori infection is now considered as an indication for treatment of the infection. However, antimicrobial drug resistance is common among H. pylori in Korea making effective therapy problematic. Country-wide studies of the local and regional antimicrobial resistance patterns are needed to choose the most appropriate therapies. H. pylori and gastric cancer eradication can be both efficient and cost effective making it possible and practical to make Korea H. pylori and gastric cancer free. There is no reason to delay.
Anti-Bacterial Agents/*therapeutic use ; Disease Eradication ; Drug Resistance, Bacterial ; Helicobacter Infections/*drug therapy/epidemiology/microbiology ; Helicobacter pylori/*drug effects/growth & development ; Humans ; Prevalence ; Primary Prevention/*methods ; Republic of Korea/epidemiology ; Risk Assessment ; Risk Factors ; Stomach Neoplasms/epidemiology/microbiology/*prevention & control ; Treatment Outcome

PURPOSETo investigate and analyze the clinical and etiological characteristics of community-acquired intraabdominal infections (CIAIs) and hospital-acquired or nosocomial intraabdominal infections (NIAIs) in a comprehensive hospital, to understand the characteristics, pathogen composition, and drug resistance of CIAIs as well as NIAIs, and to provide a reference for clinical treatment.

METHODSWe collected the clinical data of patients with intraabdominal infections admitted to our hospital from June 2013 to June 2014. In vitro drug sensitivity tests were conducted to separate pathogens, and the data were analyzed using the WHONET 5.4 software and SPSS 13.0 software.

RESULTSA total of 221 patients were enrolled in the study, including 144 with CIAIs (55 mild-moderate and 89 severe) and 77 with NIAIs. We isolated 322 pathogenic strains, including 234 strains of gram-negative bacteria, 82 strains of gram-positive bacteria, and 6 strains of fungi. Based on clinical features, NIAIs and severe CIAIs presented significantly higher values in age, length of hospital stay, mortality, and the incidence of severe intra-abdominal infection than mild-moderate CIAIs (p < 0.05). There was no significant difference in the prognosis between NIAIs and severe CIAIs. Primary diseases leading to CIAIs and NIAIs mostly were hepatobiliary diseases and gastrointestinal diseases respectively. Bacteria isolated from various types of IAIs mainly were Enterobacteriaceae; mild-moderate CIAIs mostly were mono-infection of gram-negative bacteria; NIAIs mostly were mixed infections of gram-negative and gram-positive bacteria; and severe CIAIs were from either type of infection. The rate of Extended Spectrum b-Lactamase-producing Escherichia coli and Klebsiella pneumoniae was much higher in NIAIs than in CIAIs (p < 0.05). The antimicrobial drug sensitivity of gram-negative bacteria isolated from NIAIs was significantly lower than that of CIAIs.

CONCLUSIONCIAIs and NIAIs have their own unique clinical features and epidemiological features of pathogens which should be considered during the initial empiric therapy for the rational use of antimicrobial drugs. Regional IAIs pathogenic bacteria have their own features in drug resistance, slightly different from some recommendations of 2010 Infectious Diseases Society of America guidelines.

Adult ; Aged ; Bacterial Infections ; drug therapy ; epidemiology ; Community-Acquired Infections ; drug therapy ; epidemiology ; microbiology ; Cross Infection ; drug therapy ; epidemiology ; microbiology ; Female ; Humans ; Intraabdominal Infections ; drug therapy ; epidemiology ; microbiology ; Male ; Microbial Sensitivity Tests ; Middle Aged ; Prospective Studies