OBJECTIVES: Blood culture is a one of the most important procedure for diagnosis and treatment of infectious disease, but distribution of pathogenic species and the antimicrobial susceptibility can be vary from pathogen, individual trait, regional or environmental features. In this study, we investigated the changes in frequency of occurrence and antimicrobial susceptibility pattern of blood isolates from 2005 to 2014. METHODS: Data of blood isolates from Kosin Gospel Hospital during 2005 to 2014 were analyzed retrospectively. Blood isolates were cultured for 5 days using BACTEC Plus Aerobic/F and BACTEC lytic/10 Anaerobic/F. Identification and antimicrobial susceptibility test was performed using VITEK 1 system, VITEK 2 XL, PHOENIX 100 and conventional method. RESULTS: 9,847 isolates were identified during 10 years. Among the isolates aerobic or falcutative anaerobic bacteria were isolated in 99.5% specimens, anaerobic were 0.1%, and fugi were 0.4%. Most commonly isolated bacteria were coagulase-negative Staphylococcus (CoNS) followed by Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae. Candida parapsilosis were most frequently isolated among fungi. The proportion of S. aureus, A. baumannii and E. faecium were increased, while Pseudomonas aeruginosa and Streptococcus pneumoniae decreased over decennium. Imipenem resistant K. pneumoniae were identified. Vancomycin resistant E. faecium and imipenem resistant A. baumannii were increased (7.1% in 2005 to 12.3% in 2014, 0% in 2005 to 55.6% in 2014, respectively). CONCLUSIONS: Over the last 10 year, CoNS were the most frequently isolated pathogen. Imipenem resistant K. pneumoniae was emerged. Vancomycin resistant E. faecium and imipenem resistant A. baumannii increased during this period.
Bacteremia ; Bacteria ; Bacteria, Anaerobic ; Candida ; Communicable Diseases ; Diagnosis ; Escherichia coli ; Fungi ; Gyeongsangnam-do* ; Imipenem ; Klebsiella pneumoniae ; Methods ; Pneumonia ; Pseudomonas aeruginosa ; Retrospective Studies ; Staphylococcus ; Staphylococcus aureus ; Streptococcus pneumoniae ; Vancomycin

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is known to be one of the ideal biomarkers for acute kidney injury providing early information on damage to the kidney. METHODS: We evaluated the performance for precision and the reportable range of the automated NGAL Test (Bioporto Diagnostics, Denmark) assay and compared the values of these tests with widely used point of care test. The reference interval of NGAL was established in Korean adults. RESULTS: Within run percent coefficient of variation (%CV) and total precision %CV for 2 levels were all within 5%. The reportable range was found to be acceptable for the range of 57.0 - 3182.0 ng/mL (r=0.999). The method comparison was made between Biosite's assay and Bioporto Diagnostics' (Passing and Bablok fit, y=1.94x - 5.29; x, Biosite; y, Bioporto; n=31; y range, 250 to 1,308 ng/mL; r2=0.959). The correlation was linear within the limit of 1,500 ng/mL, but not beyond this limit. The 2.5 and 97.5 percentile of the reference range for the samples were 43.2 ng/mL and 124.8 ng/mL, respectively. CONCLUSIONS: Since NGAL Test can be used in automated chemical analyzer, it can not only reduce the man power and time consumed in but also displayed excellent precision and linearity.
Acute Kidney Injury ; Biomarkers ; Chemistry, Clinical ; Immunoassay ; Lipocalins ; Nephelometry and Turbidimetry ; Neutrophils ; Reference Values

BACKGROUND: We evaluated the HbA1c assay on COBAS INTEGRA 800 Closed Tube System (Roche Diagnostics, USA). METHODS: Precision was determined following Clinical and Laboratory Standards Institute (CLSI) EP5-A2 using the Lyphochek Diabetes Control (Bio-Rad Laboratories, Canada). Two levels of QC materials were assayed in duplicates at two separate times per day for 20 days. The within-run, between-run and between-day precisions were evaluated. We compared the HbA1c of COBAS INTEGRA 800 Closed tube system using Tina quant Hemoglobin A1c Gen.2 (Roche Diagnostics, Germany) reagent with Variant II Turbo (Bio-Rad Laboratories, USA). Bias was determined following CLSI EP9-A2. RESULT: The HbA1c assay on COBAS INTEGRA 800 Closed Tube System showed excellent precision performance: at a level of 5.9%, total, between run, and between day CVs were 1.8%, 0.5%, and 1.6%, respectively. At a level of 9.6%, total, between run, and between day CVs were 1.4%, 0.3%, and 1.1%, respectively. The assay correlated well with the Variant II Turbo (y=0.9x+0.53, r2=0.9857). Mean bias against Variant II Turbo was -0.2%. Compared with Variant II Turbo, the estimate of the predicted bias at a given medical decision level (HbA1c at 6% and 9%) was -0.1% and -0.31%, respectively. CONCLUSIONS: The COBAS INTEGRA 800 Closed Tube System HbA1C assay was precise and equivalent to Variant II Turbo.
Bias (Epidemiology) ; Hemoglobins

BACKGROUND: The rapid and accurate detection of carbapenemase-producing Enterobacteriaceae (CPE) in clinical microbiology laboratories is essential for the treatment and control of infections caused by these microorganisms. This study was performed to evaluate the ability of the VITEK AST-N202 card to detect CPE isolates. MATERIALS AND METHODS: A total of 43 (Klebsiella pneumoniae, n = 37; Escherichia coli, n = 3; and Enterobacter cloacae, n = 3) CPE isolates and 79 carbapenemase-non-producing Enterobacteriaceae (CNE) isolates were included in this study. The CPE isolates harbored KPC-2 (n = 11), KPC-3 (n = 20), GES-5 (n = 5), VIM-2 (n = 2), IMP-1 (n = 1), NDM-1 (n = 2), or OXA-232 (n = 2). Of the 79 CNE isolates, eight K. pneumoniae isolates were resistant to ertapenem, imipenem, and meropenem, while the remaining 71 isolates were susceptible to the carbapenems. Antimicrobial susceptibilities were tested using the VITEK AST-N202 card, and the results were interpreted as positive when the isolates showed resistant or intermediate results. Modified-Hodge tests (MHTs) were performed using ertapenem or meropenem disks for the screening of carbapenemase production. Polymerase chain reaction (PCR) and direct sequencing were used to identify beta-lactamase genes. RESULTS: Sensitivity of MHT with ertapenem and meropenem disks for the detection of carbapenemase was 81.4% (35/43) and 81.4% (35/43), respectively, and a combination with both antibiotic disks increased the sensitivity to 88.4% (38/43). Specificity of the MHT was 100% (79/79) for the CNE isolates. Sensitivity of ertapenem, imipenem, and meropenem as assessed by the VITEK AST-N202 card was 100% (43/43), 93% (40/43), and 95.3% (41/43), respectively. Specificity (89.8%, 71/79) of the test with each carbapenem was improved to 100% (71/71) when eight carbapenem-resistant CNE isolates were excluded from the testing. CONCLUSION: The VITEK AST-N202 card showed high sensitivity for the detection of carbapenemases in Enterobacteriaceae strains. PCR and sequencing experiments for the detection of carbapenemases are recommended when clinical Enterobacteriaceae isolates show non-susceptibility to carbapenems.
beta-Lactamases ; Carbapenems ; Enterobacter cloacae ; Enterobacteriaceae* ; Escherichia coli ; Imipenem ; Mass Screening ; Pneumonia ; Polymerase Chain Reaction ; Sensitivity and Specificity

BACKGROUND: The i-Smart 30 point-of-care (POC) analyzer (i-SENS, Korea) is a compact and portable system used for the analysis of electrolytes (sodium, potassium, chloride) and hematocrit in whole blood samples. In this study, we evaluated the analytical performance of the i-Smart 30 analyzer. METHODS: Precision and sample-related percent carry-over were determined using the quality control materials. Comparison study was performed with the Stat Profile Critical Care Xpress (STP CCX; Nova Biomedical, USA) analyzer using venous whole blood samples. RESULTS: In the precision study, imprecision studies demonstrated within-run and total-run coefficients of variation within 0.5-3.9% and 0.7-4.4%, respectively, for all analytes. A good correlation was found between the i-Smart 30 analyzer and the STP CCX analyzer, except for chloride that showed high intercept. In the study of carry-over, sample-related carry-over for Na+, K+, Cl- and Hct were demonstrated as 0.84%, 0%, 0.86% and 1.56%, respectively. CONCLUSIONS: We conclude that the i-Smart 30 analyzer is suitable for routine use in clinical laboratories, especially where rapid test results are required such as emergency departments, intensive care units, and dialysis units. However, for Cl-, it is necessary that a significant correlation between this analyzer and a reference method should be demonstrated.
Critical Care ; Dialysis ; Electrolytes ; Emergencies ; Hematocrit ; Intensive Care Units ; Point-of-Care Systems ; Potassium ; Quality Control

BACKGROUND: In patients who had serum autoantibody that reacted with all screening red blood cells (panagglutination), waiting for compatible blood is likely to delay a needed transfusion. In some cases of severely diminished hemoglobin counts, the least incompatible blood may be transfused. However, the least incompatible transfusion therapy is challenged by the presence of unexpected antibody in patient's serum, which may cause a transfusion reaction. The aim of this study was to evaluate the effect of the least incompatible transfusion on clinical outcomes in patients with panagglutination. METHODS: We conducted a retrospective study of 49 patients with panagglutination on an unexpected antibody screening test between January 2006 and July 2010. In 36 patients having the least incompatible blood transfusion, changes in hemoglobin and lactate dehydrogenase (LD) values before and after transfusion were analyzed. One year mortality after initial need for transfusion was documented. RESULTS: In all 36 patients who underwent transfusion, hemoglobin values showed an increase of 1.2 (0.0~3.0) g/dL per unit without occurrence of acute transfusion reactions indicated by an increase in the LD level. The least incompatible transfusion did not show an association with increased all-cause mortality. CONCLUSION: As an alternative to the time consuming process of alloantibody detection, patients with severe anemia can be effectively transfused with "least incompatible units" in an emergency clinical setting without experiencing acute transfusion reactions.
Anemia ; Blood Group Incompatibility ; Blood Transfusion ; Emergencies ; Erythrocytes ; Hemoglobins ; Humans ; L-Lactate Dehydrogenase ; Mass Screening ; Retrospective Studies

BACKGROUND: Self-monitoring of blood glucose levels is recommended for all diabetic patients who receive insulin treatment, because such monitoring of glucose levels may aid in achieving better control in type II diabetes. Further, the use of point-of-care (POC) blood glucose testing in hospitals has increased substantially. In the present study, we validated the performance of ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip (Roche Diagnostics, Germany). METHODS: We evaluated the precision, accuracy, and maltose interference of the ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip. Further, precision was evaluated using dedicated quality control (QC) and Bio-Rad Whole Blood (WB) QC materials (Meter Trax(TM) Control; Bio-Rad, USA). Forty samples were used to compare the results obtained using the ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip with those obtained using the clinical chemistry analyzer Hitachi 7600 (Hitachi, Japan). Maltose interference was assessed at 2 glucose concentration levels at 3 maltose concentration levels. RESULTS: For each concentration level of control materials, within-run coefficient of variation (CV) and total CV obtained were less than 5%. Good correlation was obtained using the Hitachi 7600 (y = 1.02x - 0.18; r 2 = 0.996; N = 40). Effects of maltose interference were less than 10%. CONCLUSIONS: Thus, the ACCU-CHEK(R) systems show good precision and correlation with the routine clinical chemistry analyzer and allow only minimal effects of maltose interference.
Blood Glucose ; Chemistry, Clinical ; Glucose ; Humans ; Insulin ; Maltose ; Quality Control

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: In most clinical microbiology laboratories, inoculation of specimens on plates is performed manually and is a time-consuming process. The efficiency of this process can be improved by using an automated instrument. Currently, several automated instruments have been introduced for inoculation of samples. In this study, we have evaluated an automated instrument, PREVI Isola(R) (Biomerieux, France), used for inoculation of body fluids and urine specimens. METHODS: Both manual and automated instrument methods were used to inoculate 74 body fluid and 204 urine samples. Precision was evaluated by testing 3 types of urine samples (A, 6x10(3) colony-forming units (CFU)/mL; B, 3x10(4) CFU/mL; and C, >10(6) CFU/mL) in replicates of 20. Results of the 2 methods were compared by counting the isolated colonies on agar plates after incubation. The time required for both methods was also compared. RESULTS: The coefficient of variation (CV) of samples A, B, and C examined using the automated instrument method was 176.1%, 18.1%, and 12.6%, respectively. The sensitivity and specificity of testing body fluid samples were 77% and 100%, respectively, and those of urine samples were 87% each. The time required for testing 15 body fluid specimens and that for inoculation of each specimen was 9.7 min shorter using PREVI Isola(R) than using the manual method. CONCLUSIONS: The results of body fluid and urine culture by inoculation using the automated instrument, PREVI Isola(R), showed relative good agreement with those obtained using the manual method. The use of PREVI Isola(R) would be expected to reduce the time and labor involved in inoculating various kinds of specimens.
Agar ; Automation, Laboratory ; Body Fluids ; Microbiological Techniques ; Sensitivity and Specificity ; Stem Cells

BACKGROUND: Acinetobacter baumannii has a greater clinical impact and exhibits higher antimicrobial resistance rates than the non-baumannii Acinetobacter species. Therefore, the correct identification of Acinetobacter species is clinically important. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has recently become the method of choice for identifying bacterial species. The purpose of this study was to evaluate the ability of MALDI-TOF MS (Bruker Daltonics GmbH, Germany) in combination with an improved database to identify various Acinetobacter species. METHODS: A total of 729 Acinetobacter clinical isolates were investigated, including 447 A. baumannii, 146 A. nosocomialis, 78 A. pittii, 18 A. ursingii, 9 A. bereziniae, 9 A. soli, 4 A. johnsonii, 4 A. radioresistens, 3 A. gyllenbergii, 3 A. haemolyticus, 2 A. lwoffii, 2 A. junii, 2 A. venetianus, and 2 A. genomospecies 14TU. After 212 isolates were tested with the default Bruker database, the profiles of 63 additional Acinetobacter strains were added to the default database, and 517 isolates from 32 hospitals were assayed for validation. All strains in this study were confirmed by rpoB sequencing. RESULTS: The addition of the 63 Acinetobacter strains' profiles to the default Bruker database increased the overall concordance rate between MALDI-TOF MS and rpoB sequencing from 69.8% (148/212) to 100.0% (517/517). Moreover, after library modification, all previously mismatched 64 Acinetobacter strains were correctly identified. CONCLUSIONS: MALDI-TOF MS enables the prompt and accurate identification of clinically significant Acinetobacter species when used with the improved database.
Acinetobacter Infections/*microbiology/pathology ; Acinetobacter baumannii/*chemistry/classification/isolation & purification ; Bacterial Proteins/chemistry/genetics/metabolism ; Databases, Factual ; Humans ; Phylogeny ; RNA, Ribosomal, 16S/chemistry/genetics/metabolism ; *Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization