Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical breakpoint tables are commonly used as guidelines for the interpretation of antimicrobial susceptibility testing results. These are updated annually to reflect new and revised antimicrobial susceptibility breakpoints. EUCAST v.12.0, which was published in January 2022, presents updated meropenem-vaborbactam breakpoints for Enterobacterales and Pseudomonas aeruginosa. It also suggests new breakpoints of susceptibility to various antibiotics for Vibrio spp. Flow charts were updated for Streptococcus pneumoniae and Haemophilus influenzae, and the breakpoints for anaerobic bacteria were divided according to each species. Furthermore, recommendations were made for cases without antimicrobial susceptibility testing breakpoints and links to several rationale and guidance documents were provided for technical convenience.

C. striatum is part of the normal skin and mucous membrane flora in humans and is widely disseminated in the environment. Traditionally, these strains have been considered contaminants. However, C. striatum has been linked to respiratory infection, bacteremia, and endocarditis; and it is strongly related to nosocomial outbreaks. At present, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) is the most accurate routine identification method. Many C. striatum strains are multi-drug resistant, being susceptible only to vancomycin and linezolid. We should survey the antimicrobial susceptibility results regularly to monitor its resistance and consider it a possible pathogen.
Bacteremia ; Corynebacterium* ; Disease Outbreaks ; Endocarditis ; Humans ; Linezolid ; Mass Spectrometry ; Methods ; Mucous Membrane ; Skin ; Vancomycin

BACKGROUND: The recent expansion of knowledge about various ABO alleles has led to the need for a comprehensive measure to cover the numerous polymorphisms dispersed in the ABO gene. A few studies have examined the diversity of the O allele compared to A or B subgroup alleles, resulting in antigenic changes. This study investigated the relationship between the serologic and molecular genetic characteristics of the O alleles in the Korean population. METHODS: One hundred and five samples from healthy blood group O subjects were selected randomly. The isoagglutinin titer was measured using a tube agglutination and gel microcolumn assay. The ABO alleles were analyzed by sequencing exons 6 and 7 of the ABO gene. When the origin of a heterozygous nucleotide sequence was ambiguous, it was separated into a single allele using mono-allele amplification or cloning. RESULTS: The median IgM isoagglutinin titer was eight. In contrast, the median IgG anti-A and anti-B isoagglutinin titers were 64 and 32, respectively. The IgG isoagglutinin titer showed a significant increase with age (P<0.0001). Six O alleles were observed in 105 blood group O populations by sequencing. The O01 and O02 alleles were common (0.57, 0.36). Three rare O alleles (O04, O05, and O06) and one novel non-deletional O allele were found. CONCLUSION: The distribution of isoagglutinin titers of blood group O and the genetic frequency of O alleles in this study would form the basis of the development and interpretation of ABO genotyping and serologic workup in the Korean population.
Agglutination ; Alleles ; Base Sequence ; Clone Cells ; Cloning, Organism ; Exons ; Immunoglobulin G ; Immunoglobulin M ; Molecular Biology ; Sequence Analysis

Tacrolimus is one of the effective immunosuppressive drugs used after an organ transplant procedure. However, due to its narrow therapeutic range, its usefulness in preventing transplant rejection and minimizing nephrotoxicity is dependent on the monitoring of whole blood trough levels of tacrolimus. A 49-year-old kidney transplant recipient presenting with cough and general weakness was admitted to the hospital. Due to the patient's deeply compromised clinical condition, an immunosuppressive therapy was discontinued. Tacrolimus concentrations in the patient's whole blood samples were measured, using an automated chemiluminescent microparticle immunoassay (CMIA) instrument. Interference was suspected because tacrolimus concentrations after the discontinuation of tacrolimus dose were 20.9 and 18.2 ng/mL at day 2 and 3, respectively. Tacrolimus concentrations were 11.1 and 12.6 ng/mL, respectively, when re-tested using an antibody-conjugated magnetic immunoassay (ACMIA). We evaluated the relationship between the CMIA and ACMIA results, and calculated the expected values from the regression equation. Residuals were –8.4 and –4 ng/mL, respectively. There have been several cases with false detection of elevated tacrolimus concentrations using ACMIA; however, such falsely detected elevations using CMIA have rarely been reported. When unexpectedly high concentrations of tacrolimus are detected by CMIA in transplant patients, an immediate re-test using another technique might be necessary to rule out falsely elevated results.
Cough ; Graft Rejection ; Humans ; Immunoassay* ; Kidney Transplantation ; Kidney* ; Luminescence* ; Middle Aged ; Tacrolimus* ; Transplant Recipients ; Transplants

BACKGROUND: Although many laboratories use automated blood culture systems, adequate skin disinfection and optimal blood volume are still critical for successful culture. The authors undertook a nationwide survey to understand the current situation and problems of blood culture in Korea. METHODS: A survey of blood culture was performed in March and April 2010, including disinfectants, blood collection intervals, and recommended blood volumes. The laboratory physicians described the storage condition of culture bottles before delivery to the equipment. For quality control, the positive rate and skin contamination rate were studied. RESULTS: Replies to the survey were collected from 74 Korean hospitals. Povidone iodine after either isopropyl alcohol or ethanol application was the most common means of skin disinfection. Sampling of a second set of cultures was performed simultaneously in 38% of hospitals and after a 30-min interval in 50%. The recommended blood volume was 10 mL in most cases (69%), but was 20 mL in 24% of cases. The bottles were stored at 37degrees C before installation in 23% of cases and at room temperature in 16%, whereas 57% were placed directly in the equipment during the night shift. Positive rates ranged 8-10% in 32% of hospitals, 5-8% in 23%, and <5% in 12%. Skin contamination rates were 2-3% in 32% of hospitals, 1-2% in 27%, and >3% in 13%. CONCLUSION: Skin disinfection methods were rather variable. Sampling interval, blood volume, and storage of bottles should be standardized. More than 10% of the hospitals require quality improvement in terms of positive rate and skin contamination rates.
2-Propanol ; Bacteremia ; Blood Volume ; Disinfectants ; Disinfection ; Ethanol ; Povidone-Iodine ; Quality Control ; Quality Improvement ; Sepsis ; Skin

BACKGROUND: The isolation of carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly common. Continuous surveillance for these organisms is essential because their infections are closely related to outbreaks of illness and are associated with high mortality rates. The aim of this study was to develop and evaluate multiplex PCR as a means of detecting several important CPE genes simultaneously. METHODS: We aimed to develop a multiplex PCR that could detect seven CPE genes simultaneously. The multiplex PCR was composed of seven primer sets for the detection of KPC, IMP, VIM, NDM-1, GES, OXA-23, and OXA-48. We designed different PCR product sizes of at least 100 bp. We evaluated the performance of this new test using 69 CPE-positive clinical isolates. Also, we confirmed the specificity to rule out false-positive reactions by using 71 carbapenem-susceptible clinical strains. RESULTS: A total of 69 CPE clinical isolates showed positive results and were correctly identified as KPC (N=14), IMP (N=13), OXA-23 (N=12), OXA-48 (N=11), VIM (N=9), GES (N=5), and NDM (N=5) by the multiplex PCR. All 71 carbapenem-susceptible clinical isolates, including Enterococcus faecalis , Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, showed negative results. CONCLUSION: This multiplex PCR can detect seven CPE genes at a time and will be useful in clinical laboratories.
Acinetobacter baumannii ; Disease Outbreaks ; Enterobacteriaceae ; Enterococcus faecalis ; Escherichia coli ; Klebsiella pneumoniae ; Mortality ; Multiplex Polymerase Chain Reaction ; Polymerase Chain Reaction ; Pseudomonas aeruginosa ; Sensitivity and Specificity

Background: This study aimed to evaluate the diagnostic performance of the STANDARD F Influenza A/B FIA test (SD Biosensor Inc., Korea) for the rapid detection of influenza A virus in comparison with the Sofia Influenza A+B FIA (Quidel Corp., USA) and SD BIOLINE Influenza Ag A/B/A(H1N1) (Standard Diagnostic, Inc., Korea) tests. Methods: A total of 227 non-duplicated nasopharyngeal aspirates submitted for real-time RT-PCR analysis were included in the study. We used the three commercial tests in remnant samples from routine assays, according to the manufacturer’s instructions. We analyzed the diagnostic performance, including sensitivity and specificity, of the three tests. Results: Real-time RT-PCR analysis showed that 67 (29.5%) samples were positive and 160 (70.5%) were negative for influenza A virus, and that all the specimens were negative for influenza B. The overall sensitivity and specificity for influenza A virus detection were 50.7% and 100% for the STANDARD F, 50.7% and 100% for the Sofia, and 29.9% and 100% for the SD BIOLINE tests, respectively. The STANDARD F and SD BIOLINE tests showed negative results for influenza B virus in all specimens, whereas the Sofia test showed two false-positive results. Conclusion The STANDARD F Influenza A/B test showed a good diagnostic performance and may be useful for the rapid diagnosis of influenza A.

30 mg/g), the concordance rate, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of UACR, analyzed using MEDITAPE UC-11A, were 80.5, 97.5, 67.0, 70.3, and 97.1%, respectively. Using UPCR, analyzed via quantitative assay, as a reference to estimate proteinuria (UPCR >0.15 g/g), the concordance rate, sensitivity, specificity, PPV, and NPV of UPCR, analyzed using MEDITAPE UC-11A, were 86.7, 94.4, 81.5, 77.6, and 95.6%, respectively.CONCLUSIONS: UACR and UPCR, analyzed using MEDITAPE UC-11A, exhibited relatively high sensitivity and NPV, which is beneficial for laboratory screening for both albuminuria and proteinuria.]]>
Albuminuria ; Chronic Disease ; Humans ; Hypertension ; Kidney Diseases ; Mass Screening ; Proteinuria ; Renal Insufficiency, Chronic ; Sensitivity and Specificity

BACKGROUND: Streptococcus pneumoniae is the most common human pathogen causing community-acquired pneumonia. There is little information on the recent antimicrobial susceptibility patterns of S. pneumoniae in Busan and Gyeongnam of Korea. The aim of this study was to investigate the distribution and antimicrobial resistance of S. pneumoniae at 4 university hospitals in Busan and Gyeongnam. METHODS: We collected and analyzed the antimicrobial susceptibility results of 850 S. pneumoniae strains isolated from regional 4 university hospitals during the last 2 years from July 2013 through June 2015. RESULTS: Among 850 S. pneumoniae strains, 635 strains were isolated from respiratory specimens, followed by blood (N=121), CSF (N=13), and others (N=81). Antimicrobial susceptibility rates to penicillin, cefotaxime and ceftriaxone were 79.4%, 76.6% and 83.6%, respectively. The resistant rates to erythromycin and clindamycin were 80.9% and 68.2%, respectively. The resistant rates to levofloxacin were 9.2%. There were some differences in resistant rates by age groups, years, and specimen types. CONCLUSION: We found the changes of antimicrobial resistance of S. pneumoniae during the last 2 years. It is necessary to monitor the antimicrobial susceptibility of S. pneumoniae regularly for empirical therapy and for early detection of the changes of resistance.
Busan* ; Cefotaxime ; Ceftriaxone ; Clindamycin ; Drug Resistance ; Erythromycin ; Hospitals, University* ; Humans ; Korea ; Levofloxacin ; Penicillins ; Pneumonia ; Streptococcus pneumoniae* ; Streptococcus*

BACKGROUND: The XN-series (Sysmex, Japan) is the new hematology analyzer from Sysmex, with new channels to improve the accuracy of differential leukocyte count and platelet count in the low cell count range. We evaluated the analytical performance and low white blood cell (WBC) mode of the XN-2000. METHODS: Precision, linearity, and carryover were evaluated for the analyzer. We analyzed the accordance of complete blood count (CBC), reticulocyte count, and differential leukocyte count between the XN-2000 and XE-2100 (Sysmex), using 200 samples from normal controls and patients. For 80 samples with a WBC count <1.5x10(9) cells/L, the low WBC mode was evaluated by comparing the automated count with a manual differential count as the reference. RESULTS: The coefficients of variation of precision were <5% for most CBC parameters and <10% for differential leukocyte count. All results obtained with the XN-2000 showed good correlation with those obtained with the XE-2100. The correlation coefficients (r) were >0.9800 for all CBC parameters except mean corpuscular hemoglobin concentration, mean platelet volume, and platelet distribution width, and >0.9900 for differential leukocyte count except monocytes and basophils. The low WBC mode provided accurate counts for neutrophils and lymphocytes, with r>0.9300 for samples with a WBC count of 0.1-1.5x10(9) cells/L. CONCLUSIONS: The XN-2000 showed good analytical performance and correlation with the existing model, the XE-2100. The XN-2000 provided accurate results for differential leukocyte count in samples with a WBC count of 0.1-1.5x10(9) cells/L, and reduced manual slide reviews.
Basophils ; Blood Cell Count ; Blood Platelets ; Cell Count ; Erythrocyte Indices ; Hematology* ; Humans ; Leukocyte Count* ; Leukocytes ; Lymphocytes ; Mean Platelet Volume ; Monocytes ; Neutrophils ; Platelet Count ; Reticulocyte Count