Coagulase-negative staphylococci (CoNS) are reported to be the leading cause of nosocomial bloodstream infections. Staphylococcus pettenkoferi is a novel member of CoNS that was first isolated from the human blood and bursitis wound in 2002. We have reported cases of 6 S. pettenkoferi strains isolated from blood specimens, including one pathogen and 5 contaminants and catheter colonizers. Brucker Biotyper (Brucker Daltonics, Bremen, Germany) and molecular typing with 16S rRNA gene sequencing confirmed the 6 isolates as S. pettenkoferi. The conventional phenotypic identification of these isolates is not reliable owing to their inconsistent biochemical characteristics. Five of the 6 isolates were found to be resistant to oxacillin, and all isolates showed susceptibility to vancomycin and linezolid. For accurate identification of this novel species, advanced methods by using Brucker Biotyper or molecular methods such as 16S rRNA gene sequencing are required.
Aged ; Aged, 80 and over ; Anti-Bacterial Agents/pharmacology/therapeutic use ; DNA, Bacterial/chemistry/metabolism ; Drug Resistance, Bacterial/drug effects ; Female ; Humans ; Linezolid/pharmacology ; Male ; Microbial Sensitivity Tests ; Middle Aged ; Oxacillin/pharmacology ; Phenotype ; RNA, Ribosomal, 16S/chemistry/genetics/metabolism ; Sequence Analysis, DNA ; Staphylococcal Infections/drug therapy/*microbiology/pathology ; Staphylococcus/drug effects/*genetics/isolation & purification ; Vancomycin/pharmacology

Corynebacterium striatum is a commonly isolated contaminant in the clinical microbiology. However, it can be an opportunistic pathogen in immunocompromised and even immunocompetent hosts. The increasing prevalence of C. striatum infection has been associated with immunosuppression and prosthetic devices. We report a case of meningitis with cerebrospinal fluid drainage and a case of catheter-related bloodstream infection caused by C. striatum. The isolates were identified as nondiphtherial Corynebacterium species by VITEK 2 (bioMérieux, France) anaerobe and Corynebacterium card. The final identification by 16S rRNA gene sequencing analysis was C. striatum with 99.7% identity and 99.6% identity with C. striatum ATCC 6940, respectively. Both strains were sensitive to vancomycin and gentamicin, but multidrug-resistant to ciprofloxacin, penicillin, erythromycin and imipenem.
Cerebrospinal Fluid ; Ciprofloxacin ; Corynebacterium* ; Drainage ; Erythromycin ; Genes, rRNA ; Gentamicins ; Imipenem ; Immunosuppression ; Meningitis* ; Penicillins ; Prevalence ; Sepsis* ; Vancomycin

Purpose: The purpose of this study was to analyze the concept of social support of nursing students using a hybrid model and to derive a definition and attributes of social support through theoretical, fieldwork, and final analysis stages. Methods: Twenty-nine studies were analyzed in the theoretical stage. Seventeen in-depth interviews were conducted with nursing students in the fieldwork stage. In the final analysis stage, the concept of social support was defined and the attributes were derived by integrating the theoretical and fieldwork stages. Results: The attributes of social support of nursing students identified in the final analysis consisted of two dimensions and eight attributes. The two dimensions were structural and functional support. The eight attributes were social network, educational, emotional, informational, economic, positive evaluation, self-esteem support, and support by providing a role model provision. The structural dimension included the social network support attribute. The functional dimension included the remaining seven attributes. Educational support and support by providing of a role model provision were newly derived attributes that reflected specific characteristics of nursing students. Conclusion Based on the results of this study, we suggest that researchers should attempt to develop a scale to measure the social support of nursing students.

BACKGROUND: For early diagnosis and treatment of influenza, rapid influenza diagnostic tests are commonly used. We evaluated the performance of the BD Veritor System for Rapid Detection of Flu A+B (BD Veritor System; BD Diagnostics, USA) compared to multiplex real-time RT-PCR. METHODS: A total of 3,213 nasal and nasopharyngeal swab specimens in transport media from patients with influenza-like symptoms were tested with the BD Veritor System from December 2013 to April 2014. The sensitivity and specificity of 127 specimens were determined simultaneously using multiplex real-time RT- PCR with the AdvanSure RV real-time PCR (AdvanSure PCR; LG Life Sciences, Korea). RESULTS: Influenza viruses were detected in 41.3% (1,327/3,213) of all specimens tested using the BD Veritor System. Of the 127 specimens, 27 influenza A and 17 influenza B viruses were identified by the AvanSure PCR. The sensitivity and specificity of the BD Veritor System relative to the AdvanSure PCR was 85.2% and 99.0% for influenza A, and 58.8% and 99.1% for influenza B. Of the 190 specimens that tested negative using the BD Veritor System, the AdvanSure PCR detected influenza A and influenza B in 19 and 13 specimens, respectively. The mean threshold cycle (Ct) values of the antigen positive specimens were lower than those of the antigen negative specimens. CONCLUSION: The BD Veritor System showed excellent specificity for both influenza types and good sensitivity for influenza A. However, the system was less sensitive for influenza B compared to multiplex real-time RT-PCR. For accurate diagnosis of false negative specimens, a molecular diagnostic test should be performed. The BD Veritor system could be a useful tool for screening and early diagnosis of influenza.
Biological Science Disciplines ; Diagnosis ; Diagnostic Tests, Routine ; Early Diagnosis ; Humans ; Influenza B virus ; Influenza, Human* ; Mass Screening ; Orthomyxoviridae ; Pathology, Molecular ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction ; Sensitivity and Specificity

OBJECTIVE: The purpose of this study was to compare the precision of three-dimensional (3D) images acquired using iTero(R) (Align Technology Inc., San Jose, CA, USA) and Trios(R) (3Shape Dental Systems, Copenhagen, Denmark) digital intraoral scanners, and to evaluate the effects of the severity of tooth irregularities and scanning sequence on precision. METHODS: Dental arch models were fabricated with differing degrees of tooth irregularity and divided into 2 groups based on scanning sequence. To assess their precision, images were superimposed and an optimized superimposition algorithm was employed to measure any 3D deviation. The t-test, paired t-test, and one-way ANOVA were performed (p < 0.05) for statistical analysis. RESULTS: The iTero(R) and Trios(R) systems showed no statistically significant difference in precision among models with differing degrees of tooth irregularity. However, there were statistically significant differences in the precision of the 2 scanners when the starting points of scanning were different. The iTero(R) scanner (mean deviation, 29.84 +/- 12.08 microm) proved to be less precise than the Trios(R) scanner (22.17 +/- 4.47 microm). CONCLUSIONS: The precision of 3D images differed according to the degree of tooth irregularity, scanning sequence, and scanner type. However, from a clinical standpoint, both scanners were highly accurate regardless of the degree of tooth irregularity.
Dental Arch ; Imaging, Three-Dimensional* ; Tooth*

BACKGROUND: We evaluated the performance of the AdvanSure MDR-TB GenoBlot Assay kit (AdvanSure MDR-TB, LG Life Science, Korea) to detect mutations related to rifampin (RFP)- and isoniazid (INH)-resistant Mycobacterium tuberculosis complex in respiratory specimens. METHODS: From February 2010 to June 2010, a total of 542 M. tuberculosis clinical isolates were collected from pulmonary tuberculosis patients in six university hospitals across Korea. We analyzed the conventional drug susceptibility testing (DST) and compared the results with those of the AdvanSure MDR-TB. RESULTS: Compared with the conventional DST, the overall agreement rates, sensitivity, and specificity were 98.2% (532/542), 84.6% (33/39), and 99.2% (499/503), respectively, for RFP resistance and 96.1% (521/542), 79.7% (59/74), 98.7% (462/468), respectively, for INH resistance. The three common rpoB mutations were rpoB S531L (53.8%), rpoB D516V (15.4%) and rpoB H526R (7.7%) in RFP-resistant strains. For INH resistance, the katG S315T mutation (58.1%) was the most common, followed by inhA C-15T (23.0%) and katG S315N (4.1%). CONCLUSION: The AdvanSure MDR-TB showed high concordance with the conventional DST and would be helpful for early detection of RFP and INH resistance, although it requires improved sensitivity.
Biological Science Disciplines ; Hospitals, University ; Humans ; Isoniazid ; Korea ; Mycobacterium ; Mycobacterium tuberculosis ; Rifampin ; Sensitivity and Specificity ; Tuberculosis ; Tuberculosis, Pulmonary

BACKGROUND: Several automated and nonautomated systems have been developed and are commercially available for the identification of gram-negative bacilli. EASY 24E+ kit was recently developed as Korean kit for identification of gram-negative bacilli. So we evaluated the accuracy and clinical utility of EASY 24E+ compared with API 20E and VITEK GNI+. METHODS: The 221 clinical isolates of Enterobacteriaceae, including 17 C. freundii, 20 E. cloacae, 31 E. coli, 6 E. aerogenes, 29 K. pneumoniae, 3 K. oxytoca, 11 M. morganii, 13 P. mirabilis, 16 Salmonella spp., 20 S. marcescens, 9 Shigella spp., 22 S. sonnei, 16 S. typhi, 8 Y. pseudotuberculosis and 10 control strains were identified by API 20E, EASY 24E+, and VITEK GNI+. Discrepant strains were performed repeat identifications and we evaluated overall accuracy. RESULTS: All of control strains were correctly identified by three systems. The overall correct results at species level and at the genus level for 221 clinical isolates, were 96.8% and 99.1% by the VITEK GNI+, 97.7% and 97.7% by the EASY 24+ and 99.1% and 100% by the API 20E. All of Salmonella spp., S. typhi and Shigella spp. were correctly identified by all three systems and the discrepant identifications of species were 2 Y. pseudotuberculosis, 3 K. pneumoniae and 2 K. oxytoca by VITEK GNI+, 4 C. freundii and 1 P. mirabilis by EASY 24+, and 2 S. marcescens by API 20E. CONCLUSIONS: All three identification systems are accurate methods for the identification of Enterobacteriaceae, and EASY 24+ is comparable with API 20E and VITEK GNI+.
Cloaca ; Enterobacteriaceae* ; Mirabilis ; Pneumonia ; Salmonella ; Shigella

BACKGROUND: We analyzed the prevalence of anti-tuberculosis drug resistance in Mycobacterium tuberculosis isolates from respiratory specimens of patients with newly diagnosed and previously treated tuberculosis. METHODS: From February 2010 to July 2010, a total of 542 M. tuberculosis clinical isolates were collected from pulmonary tuberculosis patients in six university hospitals distributed throughout Korea. We analyzed the results of anti-tuberculosis drug resistance tests according to treatment history and geographic location. RESULTS: Among the 542 isolates, 473 (87.3%) were from newly diagnosed cases and 69 (12.7%) were from previously treated cases. The rates of multi-drug resistance (MDR), fluoroquinolone (ofloxacin, levofloxacin, and moxifloxacin) resistance, and extensive drug resistance (XDR) were 3.8%, 1.1-1.5%, and 0%, respectively, in new cases, and 21.7%, 13.0-17.4%, and 4.3%, respectively, in previously treated cases. In the previously treated cases, the proportions of XDR-TB in MDR-TB were 20% (3/15). The resistance rates were variable according to geographic location. CONCLUSION: As the anti-tuberculosis drug resistance rates are much higher in newly diagnosed cases than in previously treated patients, efforts should be made to ensure that tuberculosis treatment is successful. In addition, before the selection of an anti-tuberculosis drug treatment for previously treated patients, the susceptibility test results, including to fluoroquinolone, should be verified.
Dietary Sucrose ; Drug Resistance ; Drug Resistance, Multiple ; Extensively Drug-Resistant Tuberculosis ; Hospitals, University ; Humans ; Korea ; Mycobacterium ; Mycobacterium tuberculosis ; Ofloxacin ; Prevalence ; Tuberculosis ; Tuberculosis, Pulmonary

Background: There have been some domestic and overseas cases of anti-D alloimmunization caused by the transfusion of serologically D-negative blood. However, it is difficult to distinguish between true D-negative and DEL variants using conventional serologic typing. Therefore, we established the RHD genotyping algorithm for the detection of DEL variants and applied this algorithm to serologic D negative donors who voluntarily consented to testing. Methods: From September 2016 to December 2020, 216 RHD negative donors who were C＋ and/or E+ in previous serologic typing were recruited. The screening test was PCR amplification of the RHD exons 4, 7, 10, and a promotor. Based on the results of PCR screening, true D-negative samples and RHD variants (including DEL) were discriminated. When the result was a RHD variant, exon 9 was sequenced to identify the nucleotide changes. Full sequencing was performed if no mutations were detected at exon 9. Results: Among the 216 participants, 39 cases with the C−E−c＋e＋ phenotypes that did not meet the recruitment criteria were excluded from data analysis. Among the remaining 177 samples, 68 cases (38.4%) were RHD total deletions, 35 cases (19.8%) were RHD-CE-D hybrids, and 74 cases (41.8%) were RHD variants. Among the cases of RHD variants, 73 cases (98.6%) had c.1227G＞A substitutions and were confirmed as Asian-type DEL. Conclusion Seventy-four cases of serologic D negative donors were reclassified as RHD variants by RHD genotyping. This is believed to have contributed to the improvement of transfusion safety by lowering the risk of anti-D alloimmunization in D-negative patients.

Background: There have been some domestic and overseas cases of anti-D alloimmunization caused by the transfusion of serologically D-negative blood. However, it is difficult to distinguish between true D-negative and DEL variants using conventional serologic typing. Therefore, we established the RHD genotyping algorithm for the detection of DEL variants and applied this algorithm to serologic D negative donors who voluntarily consented to testing. Methods: From September 2016 to December 2020, 216 RHD negative donors who were C＋ and/or E+ in previous serologic typing were recruited. The screening test was PCR amplification of the RHD exons 4, 7, 10, and a promotor. Based on the results of PCR screening, true D-negative samples and RHD variants (including DEL) were discriminated. When the result was a RHD variant, exon 9 was sequenced to identify the nucleotide changes. Full sequencing was performed if no mutations were detected at exon 9. Results: Among the 216 participants, 39 cases with the C−E−c＋e＋ phenotypes that did not meet the recruitment criteria were excluded from data analysis. Among the remaining 177 samples, 68 cases (38.4%) were RHD total deletions, 35 cases (19.8%) were RHD-CE-D hybrids, and 74 cases (41.8%) were RHD variants. Among the cases of RHD variants, 73 cases (98.6%) had c.1227G＞A substitutions and were confirmed as Asian-type DEL. Conclusion Seventy-four cases of serologic D negative donors were reclassified as RHD variants by RHD genotyping. This is believed to have contributed to the improvement of transfusion safety by lowering the risk of anti-D alloimmunization in D-negative patients.