BACKGROUND: Reducing skin contamination rate and improving the positive rate in blood culture is essential for the correct diagnosis and management of sepsis. Chlorhexidine-alcohol was compared with povidone-iodine for the efficiency of disinfection. Positive rates were compared between the collection of 10 mL and 20 mL of blood per sample. METHODS: The study population included adult patients > or = 18 years old requested for blood culture in the Emergency Department. Povidone-iodine (10%) was used for antiseptic skin preparation from March to June 2011, and 0.5% chlorhexidine-alcohol from July to October 2011. The standard for blood collection was 10 mL in the first period and 20 mL in the second period. The dedicated phlebotomists had been educated on the optimal skin preparation and sample collection. RESULTS: After 10% povidone-iodine application, 31 of 2,755 samples (1.1%) were considered to be contaminated; whereas, a total of 60 of 3,064 samples (2.0%) were contaminated (P=0.011) after application of 0.5% chlorhexidine-alcohol. The positive rate of blood culture was 12.5% (345/2,755) in the first period versus 17.1% (524/3,064) in the second period (P<0.001). CONCLUSION: Both disinfectants appeared acceptable for skin preparation for blood culture collection, although chlorhexidine-alcohol had a higher contamination rate than povidone-iodine. The positive rate of blood culture was in accordance with the amount of sample collected. Continuous education and monitoring are needed for the proper collection and management of blood culture.
Adult ; Antisepsis ; Blood Volume ; Disinfectants ; Disinfection ; Emergencies ; Humans ; Povidone-Iodine ; Sepsis ; Skin

BACKGROUND: Mycoplasma pneumoniae (MP) is a major cause of community-acquired pneumonia in children. Currently, no study exists regarding the frequency of the mycoplasmal antibody on Jeju Island. The aim of the present study was to investigate the frequency of mycoplasmal antibody among children living on Jeju Island. METHODS: From March 2009 to February 2011, the frequency of mycoplasmal antibody among 1580 pediatric (<10 years old) patients who were tested for the mycoplasmal antibody titer in Cheju Halla Hospital were retrospectively investigated. The authors also analyzed the positive rates according to age, sex, and season. RESULTS: The frequency of mycoplasmal antibody titers were 69.4% for an antibody titer >1:40, 20.8% in an antibody titer >1:320, and 10.7% in an antibody titer >1:640. The positive rates of each antibody titer were lowest in children under the age of 6 months, and the positive rates increased gradually with age until 4 years, where the frequency showed a "plateau." There were minor cyclic increases of positive rate (>1:320, >1:640) every three months from August 2009 to June 2010, and there was a major increase of positive rate (>1:320, >1:640) from July 2010 to January 2011. However, there was no positive rate cyclic pattern of mycoplasmal antibody in the lower titer (>1:40) patients. CONCLUSION: The frequency of mycoplasmal antibody titer is lowest under the age of 6 months. The positive rates rise gradually with age until the age of 4 years. The present study showed minor peaks of mycoplasmal antibody titer every three months and a major peak of mycoplasmal antibody titer. The results can be helpful for the interpretation and diagnosis of MP among pediatric patients on Jeju Island.
Antibodies ; Child ; Humans ; Mycoplasma ; Mycoplasma pneumoniae ; Pneumonia ; Pneumonia, Mycoplasma ; Retrospective Studies

BACKGROUND: This study compared three non-molecular methods for the detection of methicillin-resistance directly from blood cultures containing Staphylococcus aureus: penicillin-binding protein (PBP) 2a latex agglutination (LA), PBP2a immunochromatographic assay (ICA) and MRSA chromogenic medium (CM). METHODS: Fifty methicillin-resistant S. aureus (MRSA) and 50 methicillin-susceptible S. aureus (MSSA) were seeded into blood-culture bottles. When isolates returned a positive signal, 5 mL of culture was added to serum separator tubes and centrifuged at 1,300 g for 10 min. The pellets were then used as the inoculum for the PBP2a LA, MRSA-CM and PBP2a ICA. The pure colony was used for PBP2a LA test, additionally. RESULTS: The respective sensitivities and specificities were 98 and 100% for PBP2a ICA, and 100 and 100% for MRSA-CM in direct detection of MRSA from positive blood culture. The results of PBP2a LA test using pure colony were entirely compatible with those by mecA gene PCR but the PBP2a LA test using the pellets directly isolated from positive blood culture showed sometimes ambiguous agglutination; its sensitivity and specificity were 78 and 100%, if ambiguous results were scored as negative, and were 90 and 92%, if ambiguous results were scored as positive, respectively. CONCLUSION: For direct detection of MRSA in positive blood culture, MRSA-CM and PBP2a ICA provided excellent results. The PBP2a LA test using pure colony also gave excellent results but the PBP2a LA test by the direct method using pellet of positive blood culture was slightly less sensitive than the other two methods.
Adenosine ; Agglutination ; Immunochromatography ; Latex ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Penicillin-Binding Proteins ; Polymerase Chain Reaction ; Seeds ; Sensitivity and Specificity ; Staphylococcus

BACKGROUND: Previous antibiotic exposure may inhibit the growth of microorganisms in blood culture bottles. The authors investigated the frequency of previous antibiotic usage and analyzed the relationships among antibiotic usage, microbiological culture results and mortality of sepsis patients. METHODS: From April to May 2011, all blood cultures requested from inpatients were analyzed according to the admitted ward and antibiotic prescription records. The BacT/Alert 3D system (bioMerieux Inc.) was used with a standard bottle (SA, SN) for blood culture. RESULTS: Of 900 inpatients, 48% had been receiving antimicrobial agents when blood cultures were ordered. This group had a significantly higher mortality rate (36.2%) compared to the patients who had not received antibiotics (11.1%). Gram-negative rod bacteremia (37.1%) and candidemia (100%) resulted in a significantly higher mortality rate compared to Gram-positive cocci bacteremia (16.4%). In the analysis of 21 cases resulting in death, 15 (71.4%) patients died before or on the date when blood culture results were reported. CONCLUSION: Patients who receive antibiotics prior to blood collection may be at a higher risk for mortality. In the present study, Gram-negative rod bacteremia and candidemia cases showed a rapid progression of sepsis as indicated by Gram staining and thus should be regarded seriously.
Anti-Bacterial Agents ; Anti-Infective Agents ; Bacteremia ; Candidemia ; Gram-Positive Cocci ; Humans ; Inpatients ; Prescriptions ; Sepsis ; Sydnones

BACKGROUND: The emergence of non-typhoidal Salmonella (NTS) with decreased susceptibilities to fluoroquinolone, ampicillin, or ceftriaxone has been reported worldwide. However, current surveillance studies of resistance among NTS in Korea are limited. Thus, the antimicrobial susceptibilities; resistance mechanisms such as extended-spectrum beta-lactamase (ESBL), plasmid-mediated AmpC beta-lactamase (PABL), and plasmid-mediated quinolone resistance (PMQR); and molecular epidemiologic characteristics were investigated in the present study. METHODS: National Institute of Health and National Veterinary Research and Quarantine Service collected NTS strains from 219 clinical and 293 non-clinical specimens from 2006 to 2008. The antimicrobial susceptibilities were determined using the Clinical and Laboratory Standards Institute disk diffusion test. ESBL, PABL, and qnr genotyping were performed using PCR and nucleotide sequencing. Pulsed-field gel electrophoresis was used for the molecular epidemiologic study. RESULTS: The resistance to ampicillin in clinical and non-clinical NTS was 49% and 18 to 47%, respectively. The resistance rates to trimethoprim-sulfamethoxazole in clinical and non-clinical NTS were 8% and 0 to 41%, respectively. The rates to extended-spectrum cephalosporin were 0 to 1%. One CTX-M-15-producing isolate and four CMY-2-producing isolates were detected. Notably, PFGE analysis showed four isolates carrying bla CMY-2, including one non-clinical strain had high clonality. Although the rate of ciprofloxacin resistance was very low, two qnrS1-carrying NTS strains were detected in non-clinical specimens. CONCLUSION: The resistance rates to ampicillin in both clinical and non-clinical NTS were high, while those to trimethoprim-sulfamethoxazole varied depending on the specimen. NTS strains harboring CTX-M-15-type ESBL or CMY-2-type PABL were detected even though the resistance rates to cephalosporins were very low. Four NTS strains carrying the blaCMY-2-gene implied zoonotic infection. Continuous effort to minimize transfer of resistance genes in NTS is necessary.
Ampicillin ; Animals ; Bacterial Proteins ; beta-Lactamases ; Ceftriaxone ; Cephalosporins ; Ciprofloxacin ; Diffusion ; Electrophoresis, Gel, Pulsed-Field ; Humans ; Korea ; Lifting ; Polymerase Chain Reaction ; Quarantine ; Salmonella ; Sprains and Strains ; Trimethoprim, Sulfamethoxazole Drug Combination

BACKGROUND: Diagnosis of nontuberculous mycobacterium (NTM) is challenging, and clinical, radiological and microbiological criteria should be met. Traditionally, culture results on solid media have been reported semi-quantitatively, but no study exists regarding the clinical significance of low-colony count culture reports. The authors of the present study analyzed the clinical significance of low-colony count specimens of NTM with a greater than three-year follow-up period. METHODS: A total of 341 clinical isolates were evaluated among the isolates at Seoul National University Hospital and Seoul National University Borame Hospital from October 2005 to September 2006. Colony count less than 50 was considered a low-colony count specimen. Identifications of NTM from all the isolates were performed using a DNA chip (PCR reverse hybridization, LG Life Science, Korea). Clinical significance was analyzed by reviewing the medical records of patients with greater than three years of follow-up data after NTM isolation from respiratory samples. RESULTS: NTM lung disease was observed in 27.0% of the patients with low-colony count specimens among 167 patients with respiratory samples, and 70.4% of the patients were treated. The low-colony count patients had less NTM lung disease, longer incubation period, and less acid fast bacilli-positivity than patients with a colony count greater than 50. CONCLUSION: The prevalence of NTM lung disease with a low-colony count specimen was greater than 25%. In a clinical setting, NTM lung disease should not be excluded only on the basis of a low-colony count.
Biological Science Disciplines ; Chimera ; Follow-Up Studies ; Humans ; Lung Diseases ; Medical Records ; Nontuberculous Mycobacteria ; Oligonucleotide Array Sequence Analysis ; Prevalence

Clinical isolates of Acinetobacter spp. in Korea exhibit higher antimicrobial resistance rates than in foreign countries and frequently show multi-drug resistance. Approximately 67% (272/405) of Acinetobacter baumannii isolates collected from 19 hospitals in Korea in 2008 exhibited intermediate susceptibility or resistance to imipenem and/or meropenem. The most important mechanisms in acquiring carbapenem resistance in A. baumannii in Korea are production of OXA-23 and overproduction of OXA-51, while that in non-baumannii Acinetobacter is the production of metallo-beta-lactamases. All the carbapenem-resistant A. baumannii isolates were identified as clonal complex 92 and belonged to worldwide clone 2.
Acinetobacter ; Acinetobacter baumannii ; Clone Cells ; Drug Resistance, Multiple ; Imipenem ; Korea ; Thienamycins

BACKGROUND: The isolation of nontuberculous mycobacteria (NTM) has been increasing worldwide as well as its clinical importance. The aim of this study was to investigate the distribution and clinical significance of NTM that has been isolated from respiratory specimens during a recent two-year period at a tertiary hospital. METHODS: We analyzed respiratory samples that were obtained between January 2009 and December 2010 for AFB culture. We retrospectively reviewed the electronic medical records of these patients to obtain both clinical and radiologic information. NTM pulmonary disease was defined by using the guidelines provided by the America Thoracic Society/Infectious Diseases Society of America. RESULTS: Among the 1,601 specimens that resulted in a positive AFB culture, 310 (19.4%) were NTM. In 189 patients, the most common isolate was M. avium-intracellulare complex (MAC) (127, 67.2%), which was then followed by M. abscessus (31, 16.4%), M. fortuitum (10, 5.3%), M. kansasii (9, 4.8%), and other NTM species. Of these, 93 (49.2%) patients were diagnosed with NTM pulmonary disease. MAC, M. abscessus, and M. kansasii were more virulent than the other species. None of the cases of NTM pulmonary disease were caused by M. fortuitum, M. chelonae, M. peregrinum, M. terrae complex, or M. gordonae. CONCLUSION: In Korea, the prevalence of NTM isolates is increasing, as are the cases of pulmonary disease. The pathogenic potential of NTM differs enormously by species and as a result the treatment of NTM lung disease depends on which species has caused the infection. The isolation and identification of NTM isolated from respiratory specimens are mandatory in order for clinical microbiology laboratories to make an accurate diagnosis and suggest the proper treatment of the NTM disease.
Americas ; Electronic Health Records ; Humans ; Korea ; Lung Diseases ; Nontuberculous Mycobacteria ; Prevalence ; Retrospective Studies

BACKGROUND: The aim of the present study was to investigate the epidemiologic characteristics of extrapulmonary tuberculosis (EPTB) in Korea. In addition, the results of culture-confirmed (CC) EPTB were compared with those of clinically-diagnosed (CD) EPTB. METHODS: We retrospectively reviewed non-duplicate data of tuberculosis from the Samsung Medical Center from 1995 to 2010. A total of 6,249 and 38,726 cases of tuberculosis were CC and CD EPTB cases, respectively. The cases were categorized according to the type of specimen or by the clinically-affected sites. RESULTS: The proportions of EPTB among all tuberculosis cases were 12% (745/6,249) and 22% (8,608/38,726) of the CC and CD cases, respectively. The distribution of both age and gender between pulmonary tuberculosis (PTB) and EPTB cases were significantly different (P<0.001). The most common types of EPTB were tuberculous lymphadenitis, pleural TB, and abdominal TB. Pleural involvement was more common in males, while lymph node involvement was observed more frequently in females in both the CC and CD cases (M/F ratio in regards to pleura were 1.63 and 2.08, while M/F ratio in regards to the lymph node were 0.46 and 0.54). CONCLUSION: The dataset of EPTB cases in Korea was first evaluated over a 16-year period and compared the cases of CC EPTB to those of CD EPTB. The epidemiologic characteristics of EPTB were different from that of PTB as well as the EPTB of other countries. The present study might provide useful information regarding the epidemiology of EPTB in Korea and other countries.
Female ; Humans ; Korea ; Lymph Nodes ; Male ; Pleura ; Retrospective Studies ; Tuberculosis ; Tuberculosis, Lymph Node ; Tuberculosis, Pulmonary

BACKGROUND: Clostridium difficile is the main etiologic agent of antibiotic-associated diarrhea and the most common cause of hospital-acquired diarrhea. Recently, the incidence of C. difficile infections (CDI) has increased and new highly virulent C. difficile strains have emerged. Therefore, accurate and rapid diagnosis is needed. We compared the results of using chromID C. difficile (chromID CD, bioMerieux, France) with the conventional C. difficile Selective Agar (CDSA; BD, USA) for the isolation of C. difficile. METHODS: A total of 738 stool specimens of suspected CDI patients at the Severance Hospital from July to August 2011 were inoculated onto CDSA. Among them, 104 stool specimens revealed colonies on CDSA that were then re-inoculated onto chromID CD. The stool samples were stored at -20degrees C until the time of the re-inoculation. Cultured agars were interpreted after 24 hrs and 48 hrs, respectively. Species identification was performed on the basis of colony characteristics on agar plates as well as the ATB 32A system (API System SA, France). RESULTS: The recovery rates of CDSA and chromID CD were 30.1% and 77.5% after 24 hrs, and 77.5% and 98.6% after 48 hrs, respectively. All of the C. difficile isolates were recovered as typical gray/black colonies on chromID CD. CONCLUSION: The performance of chromID CD for the isolation of C. difficile was better than that of conventional CDSA. The chromID CD could provide easy and sensitive detection of C. difficile even after 24hrs of incubation.
Agar ; Clostridium ; Clostridium difficile ; Diarrhea ; Humans ; Incidence