1.Trends in Microorganisms Isolated from Blood Cultures at a Veterans Hospital from 2012 to 2015.
Misuk JI ; Youn Mi CHOI ; Eunsin BAE ; Choon Kwan KIM
Journal of Laboratory Medicine and Quality Assurance 2017;39(3):141-146
Blood culture is important to detecting bacteremia and fungemia in patients with suspected sepsis. We observed a four-year trend of blood culture isolates in the frequency by age group and in vitro antimicrobial susceptibility patterns obtained at VHS Medical Center, the largest veterans hospital in Korea. Blood cultures collected between 2012 and 2015 were analysed retrospectively. Of 68,352 blood specimens, 7,901 isolates were identified during the study period. Seventy-two percent of the isolates were gram-positive cocci, 18% were gram-negative rods, and 6% were fungi. The frequency of bacteremia/fungemia in patients who were 80–89 years old was 43.8%, the highest rate among all age groups, and the mean age of patients diagnosed by blood culture was 77 years old. Coagulase-negative staphylococcus (52.3%), Staphylococcus aureus (8.3%), enterococci (7.5%), Escherichia coli (6.4%), and Klebsiella pneumoniae (3.9%) were the bacteria most commonly isolated. The percentage of methicillin-resistant S . aureus increased in 2015 (76%) relative to that in 2012–2014 (63%–65%), and that of vancomycin-resistant Enterococcus faecium was 17%–22% with no significant changes through time. Among the gram-negative isolates, the ciprofloxacin resistance rate increased to 51.4% (E. coli ) and 31.1% (K. pneumoniae ) in 2015, but imipenem or ertapenem resistance was still very rare, with resistance rates of less than 0.5%. Acinetobacter baumannii showed a high rate of resistance (over 70%) to imipenem and ciprofloxacin throughout the study. In Pseudomonas aeruginosa , the resistance rates of imipenem and ciprofloxacin increased dramatically over time. This analysis confirmed a decrease in antimicrobial susceptibility of gram-negative rods isolated by blood culture.
Acinetobacter baumannii
;
Bacteremia
;
Bacteria
;
Ciprofloxacin
;
Enterococcus faecium
;
Escherichia coli
;
Fungemia
;
Fungi
;
Gram-Positive Cocci
;
Hospitals, Veterans*
;
Humans
;
Imipenem
;
In Vitro Techniques
;
Klebsiella pneumoniae
;
Korea
;
Methicillin Resistance
;
Pneumonia
;
Pseudomonas aeruginosa
;
Retrospective Studies
;
Sepsis
;
Staphylococcus
;
Staphylococcus aureus
;
Veterans*
2.Clinical Utility of Measurement of Vitamin D-Binding Protein and Calculation of Bioavailable Vitamin D in Assessment of Vitamin D Status.
Hyun Jeong KIM ; Misuk JI ; Junghan SONG ; Hee Won MOON ; Mina HUR ; Yeo Min YUN
Annals of Laboratory Medicine 2017;37(1):34-38
BACKGROUND: The associations of vitamin D deficiency with various clinical conditions highlighted the importance of vitamin D testing. Currently, clinicians measure only the total 25-hydroxyvitamin D [25(OH)D] concentration, regardless of its bioavailability. We aimed to determine the effect of vitamin D-binding protein (VDBP) on 25(OH)D bioavailability. METHODS: Serum samples were collected from 60 healthy controls, 50 pregnant women, and 50 patients in intensive care units (ICUs). Total 25(OH)D was quantified by liquid chromatography with tandem mass spectrometry, and VDBP levels were determined by using an ELISA kit (R&D Systems, USA). The bioavailable 25(OH)D levels were calculated by using total 25(OH)D, VDBP, and albumin concentrations. RESULTS: In comparison with healthy controls, the total 25(OH)D concentration was significantly lower in ICU patients (median, 11.65 vs 18.25 ng/mL; P<0.00001), but no significant difference was noted between pregnant women (18.25 ng/mL) and healthy controls. The VDBP level was significantly lower in ICU patients (95.58 vs 167.18 µg/mL, P=0.0002) and higher in pregnant women (225.01 vs 167.18 µg/mL, P=0.008) compared with healthy controls. Nonetheless, the calculated bioavailable 25(OH)D levels of ICU patients and pregnant women were significantly lower than those of healthy controls (1.97 and 1.93 ng/mL vs 2.56 ng/mL; P=0.0073 and 0.0027). CONCLUSIONS: A single marker of the total 25(OH)D level is not sufficient to accurately evaluate vitamin D status, especially in pregnant women. In cases where VDBP concentrations may be altered, VDBP measurements and bioavailable 25(OH)D calculations may help to determine vitamin D status accurately.
Adult
;
Aged
;
Chromatography, High Pressure Liquid
;
Enzyme-Linked Immunosorbent Assay
;
Female
;
Humans
;
Intensive Care Units
;
Male
;
Middle Aged
;
Pregnancy
;
Pregnant Women
;
Serum Albumin/analysis
;
Tandem Mass Spectrometry
;
Vitamin D/*blood
;
Vitamin D-Binding Protein/*blood
3.Evaluation of the Performance of the MicroScan Pos Breakpoint Combo Panel Type 28 for Susceptibility Testing of Staphylococcus aureus: Low-range Minimum Inhibitory Concentration of Vancomycin, Cefoxitin Screening, and Inducible Clindamycin Resistance Dete.
Misuk JI ; Miyoung LEE ; Sinae NOH ; Mi Na KIM
The Korean Journal of Laboratory Medicine 2010;30(6):637-646
BACKGROUND: Susceptibility testing of Staphylococcus aureus often requires cumbersome supplementary tests. MicroScan Pos Breakpoint Combo Panel Type 28 (PBC28) (Siemens, USA) includes cefoxitin screening to detect methicillin-resistant Staphylococcus aureus (MRSA), inducible clindamycin resistance detection (ICD), and determination of low-range minimum inhibitory concentration of vancomycin (0.5-16 microgram/mL). The purpose of this study was to evaluate the performance of PBC28 in comparison with that of Pos Combo Type 1A (PC1A) (Siemens). METHODS: From December 2009 to March 2010, 500 non-duplicate clinical isolates of S. aureus were tested with PC1A and PBC28. Categorical agreements (CA) between the interpretations of the 2 panels were estimated. The presence of the mecA gene was determined by PCR, and double-disk diffusion test (D-test) was performed on the isolates resistant to erythromycin but susceptible or intermediately resistant to clindamycin. Ninety-six isolates representing various vancomycin minimum inhibitory concentrations (MICs) were tested in parallel with repeat PBC28, broth macrodilution, and epsilometer test (E test). RESULTS: The CA was 99.3% with a very major error (VME) of 0.2%, major error (ME) of 0.1%, and minor error (mE) of 0.4% in total. PBC28 showed 100% CA for 1 isolate with vancomycin MIC of 4 microgram/mL and 35 isolates (7.0%) with MIC of 2 microgram/mL. However, only 15, 27, and 35 isolates with vancomycin MIC of 2 microgram/mL showed 100% CA in repeat PBC28, broth macrodilution, and E test, respectively. PC1A and PBC28 detected all 314 mecA-positive isolates. Among the 63 isolates tested with the D-test, 58 (92.1%) were positive, and the results were 100% concordant with those of ICD. CONCLUSIONS: PBC28 can be appropriate susceptibility testing of S. aureus, including MRSA detection and ICD. However, the lower-range vancomycin MIC test was not reproducible enough to reliably differentiate MIC of 2 microgram/mL from MIC< or =1 microgram/mL.
Anti-Bacterial Agents/*pharmacology
;
Bacterial Proteins/genetics
;
Cefoxitin/*pharmacology
;
Clindamycin/*pharmacology
;
Drug Resistance, Bacterial
;
Methicillin-Resistant Staphylococcus aureus/genetics/isolation & purification
;
*Microbial Sensitivity Tests
;
Reagent Kits, Diagnostic
;
Sensitivity and Specificity
;
Staphylococcus aureus/*drug effects/genetics/isolation & purification
;
Vancomycin/*pharmacology
4.Cryptic Insertion of the BCR Gene at 9q34 in Philadelphia-Negative Chronic Myelogenous Leukaemia.
Hyun Jeong KIM ; Misuk JI ; Hanah KIM ; Hee Won MOON ; Mina HUR ; Yeo Min YUN
Journal of Laboratory Medicine and Quality Assurance 2015;37(2):110-114
Chronic myelogenous leukaemia (CML) is a myeloproliferative neoplasm that is almost always characterised by the presence of t(9;22)(q34;q11.2). Approximately 5% to 10% of CML patients lack cytogenetic evidence of t(9;22)(q34;q11.2) but have the breakpoint cluster region (BCR)/ABL1 fusion, as revealed by fl uorescence in situ hybridisation (FISH) or the reverse transcription-polymerase chain reaction (RT-PCR). We present a case of Philadelphia-negative CML with a cryptic insertion of BCR at 9q34. A 22-year-old woman incidentally presented with marked leucocytosis and anaemia. Her complete blood count results were as follows: white blood cells, 238.61x10(9)/L; haemoglobin, 9.6 g/dL; platelets, 395x10(9)/L. A peripheral blood smear showed leucocytosis with neutrophilia, basophilia, left-shifted neutrophils, and circulating blasts comprising 2% of the total leucocytes. The bone marrow showed a striking increase in megakaryocytes and granulocytic precursors. The myeloid/erythroid ratio was 7.4:1, and blasts comprised up to 1.8% of all nucleated cells. Bone marrow sections revealed active megakaryopoiesis and granulopoiesis with 100% cellularity. Chromosomal analysis revealed a normal karyotype. However, interphase FISH using a dual-colour BCR/ABL1 fusion probe showed an atypical pattern consisting of one red, two green, and one fusion (1R2G1F) signal in 97.5% of the 200 analysed cells. Metaphase FISH revealed a single BCR/ABL1 fusion signal on chromosome 9. RT-PCR was positive for BCR/ABL1 (b3a2). Quantitative PCR revealed a normalised copy number of 15.32. The patient started her treatment with imatinib, reached a complete molecular response eight months afterwards, and has been coping well without any adverse events.
Blood Cell Count
;
Bone Marrow
;
Chromosomes, Human, Pair 9
;
Cytogenetics
;
Female
;
Humans
;
Interphase
;
Karyotype
;
Leukocytes
;
Megakaryocytes
;
Metaphase
;
Neutrophils
;
Polymerase Chain Reaction
;
Strikes, Employee
;
Young Adult
;
Imatinib Mesylate
5.Performance Evaluation of the JEOL BioMajesty JCA-BM6010/C Automated Clinical Chemistry Analyzer.
Hyeong Nyeon KIM ; Misuk JI ; Hee Won MOON ; Mina HUR ; Yeo Min YUN
Laboratory Medicine Online 2017;7(3):111-119
BACKGROUND: JEOL BioMajesty JCA-BM6010/C (JCA-BM6010/C, JEOL Ltd., Japan) is a recently developed ultra-compact automated clinical chemistry analyzer with a throughput of 1,200 tests per hour. Here, we present the first performance evaluation of JCA-BM6010/C. METHODS: We evaluated the precision, linearity, correlation, accuracy, and carryover of 11 analytes (ALP, ALT, AST, calcium, creatinine, GGT, glucose, LDH, total bilirubin, total protein, and uric acid) using the JEOL closed reagent (JEOL Ltd.) according to the guidelines of the Clinical Laboratory Standards Institute. Linearity was further evaluated for ALT, AST, and GGT using open reagents by Sekisui (Japan). The performance of JCA-BM6010/C was compared to that of the Roche-Hitachi Cobas 8000 c702 chemistry autoanalyzer (Cobas 8000, Roche Diagnostics, Switzerland). Its performance using open reagents from Denka Seiken (Japan), Roche, and Sekisui was also evaluated. RESULTS: The total coefficients of variation (CV) for all analytes were 1.0–2.7%. Linearity was observed for all analytes over the entire tested analytical range (R²≥0.99). The results of JCA-BM6010/C strongly correlated (r≥0.988) with those of Cobas 8000 for all evaluated analytes except LDH (r=0.963), as well as for all open reagents. Recovery rates for creatinine, glucose, calcium, and uric acid were 96.6–101.5% and 98.7–109.3% with the JEOL exclusive and open reagents, respectively. Sample carryover was less than 0.34%. CONCLUSIONS: JCA-BM6010/C showed acceptable performance in the precision, linearity, correlation, accuracy, and sample carryover analyses and in the method comparison. Therefore, it could be a useful routine laboratory medical analyzer.
Bilirubin
;
Calcium
;
Chemistry
;
Chemistry, Clinical*
;
Creatinine
;
Glucose
;
Indicators and Reagents
;
Methods
;
Uric Acid
6.Establishing Reference Intervals for Soluble ST2 Assay in a Korean Population.
Mikyoung PARK ; Misuk JI ; Hanah KIM ; Hee Won MOON ; Mina HUR ; Yeo Min YUN
Laboratory Medicine Online 2017;7(4):176-181
BACKGROUND: Soluble ST2 (sST2) has emerged as a biomarker of heart failure. Previous studies indicated 35 ng/mL of sST2 as the clinically prognostic cut-off value. This study aims to establish reference intervals in a Korean population using an sST2 assay and to evaluate the applicability of the cut-off value. METHODS: From March to May 2014, sST2 levels were assayed in serum samples of 255 cardio-healthy Koreans (128 men and 127 women) using the Presage ST2 ELISA kit (Critical Diagnostics, USA). The reference interval for sST2 was defined using the nonparametric percentile method according to the CLSI EP28-A3c guideline. RESULTS: The median sST2 concentrations were 23.8 ng/mL (interquartile range (IQR), 19.0-28.7), 26.6 ng/mL (IQR, 21.0-30.9), and 21.9 ng/mL (IQR, 17.3-26.5) for the entire cohort, men, and women, respectively. sST2 levels were significantly higher in men than in women (P<0.0001). The 97.5th percentile upper reference limits for sST2 were 43.8 ng/mL, 49.6 ng/mL, and 35.4 ng/mL for the cohort, men, and women, respectively. Gender-specific upper reference limits were similar to limits reported by other studies. CONCLUSIONS: We suggest that gender-specific reference intervals should be used for the Korean population, as application of a single cut-off value of 35 ng/mL may be overcautious of the possibility of false positivity, especially in men.
Cohort Studies
;
Enzyme-Linked Immunosorbent Assay
;
Female
;
Heart Failure
;
Humans
;
Male
;
Methods
7.Mycoplasma pneumoniae Pneumonia Unresponsive to Macrolide Treatment.
Misuk JI ; Heungsup SUNG ; Tae Sun SHIM ; Woori JANG ; Mi Na KIM
Laboratory Medicine Online 2012;2(4):226-231
We present a case of community-acquired pneumonia (CAP) that developed in a previously healthy young woman. She was diagnosed with Mycoplasma pneumoniae pneumonia, but did not respond to macrolide treatment. The pathogens of CAP was examined using chest radiographs, computed tomography, and various laboratory tests including Mycoplasma IgG and IgM antibodies, blood and sputum cultures, and PCR for M. pneumoniae, Legionella pneumophila, and Chlamydophila pneumoniae. In this study, differential diagnosis of the pathogens and analysis of the mechanisms underlying their resistance to macrolide treatment were performed, and the results were discussed. After changing the antimicrobial to quinolone, the patients' clinical symptoms and radiographic findings improved, and she was discharged after 8 days.
Antibodies
;
Chlamydial Pneumonia
;
Chlamydophila pneumoniae
;
Diagnosis, Differential
;
Female
;
Humans
;
Immunoglobulin G
;
Immunoglobulin M
;
Legionella pneumophila
;
Mycoplasma
;
Mycoplasma pneumoniae
;
Pneumonia
;
Pneumonia, Mycoplasma
;
Polymerase Chain Reaction
;
Sputum
;
Thorax
8.Analytical Evaluation of the DiaSys Albumin in Urine/CSF FS Kit for Urine Albumin Measurement Using a JEOL BioMajesty JCA-BM6010/C Analyzer.
Hyun Jeong KIM ; Misuk JI ; Hee Won MOON ; Mina HUR ; Yeo Min YUN
Laboratory Medicine Online 2016;6(2):64-69
BACKGROUND: High albuminuria is defined as albumin excretion of >30 mg/24 hr or an albumin-to-creatinine ratio of 30 mg/g in a random urine sample. We assessed the analytical performance of the Albumin in Urine/CSF FS kit (DiaSys Inc., UK) using a BioMajesty JCA-6010/C analyzer (JEOL Inc., Japan). METHODS: Urine albumin concentrations were measured by the Albumin in Urine/CSF FS kit using a BioMajesty JCA-BM6010/C analyzer. Imprecision, linearity, and carry-over were measured according to the Clinical Laboratory and Standards Institute documents EP10 and EP9. The assay was compared with the ALB-T TQ Gen.2 (Roche, Germany) assay on a Cobas8000 C702 (Roche, Germany), the Tina-Quant Albumin (Roche, Switzerland) assay on a Hitachi7600-210 (Hitachi, Japan), and an Abbott urine albumin assay (Abbott Laboratories, USA) on a TBA 200FR (Toshiba, Japan) using 50 random urine samples. RESULTS: Within-run and total imprecision were 0.551-1.023% and 0.551-1.214%, respectively. Linearity ranged from 6.31 to 30.60 mg/dL, and functional sensitivity was 0.5 mg/dL. Results from the Albumin in Urine/CSF FS kit showed good correlation with the ALB-T TQ Gen.2 (r=0.987) and the Tina-Quant Albumin assays (r=0.991). However, the four assays categorized 18 of 50 urine samples into different albuminuria groups. CONCLUSIONS: Albumin in Urine/CSF FS testing on a BioMajesty JCA-BM6010/C analyzer showed good linearity, functional sensitivity, precision, and correlation with the ALB-T TQ Gen.2 and Tina-Quant Albumin assays. However, because some samples were categorized into different albuminuria groups by the different assays, further studies on the standardization of albuminuria assays are needed.
Albuminuria
9.Genetic Polymorphism of CYP2D6 and Clomiphene Concentrations in Infertile Patients with Ovulatory Dysfunction Treated with Clomiphene Citrate.
Misuk JI ; Kwang Rae KIM ; Woochang LEE ; Wonho CHOE ; Sail CHUN ; Won Ki MIN
Journal of Korean Medical Science 2016;31(2):310-314
CYP2D6 is primarily responsible for the metabolism of clomiphene citrate (CC). The purpose of the present study was to investigate the relationship between CYP2D6 genotypes, concentrations of CC and its major metabolites and drug response in infertility patients. We studied 42 patients with ovulatory dysfunction treated with only CC. Patients received a dose of 100 mg/day CC on days 3-7 of the menstrual cycle. CYP2D6 genotyping and measurement of CC and the major metabolite concentrations were performed. Patients were categorized into CC responders or non-responders according to one cycle response for the ovulation. Thirty-two patients were CC responders and 10 patients were non-responders with 1 cycle treatment. The CC concentrations were highly variable within the same group, but non-responders revealed significantly lower (E)-clomiphene concentration and a trend of decreased concentrations of active metabolites compared to the responders. Nine patients with intermediate metabolizer phenotype were all responders. We confirmed that the CC and the metabolite concentrations were different according to the ovulation status. However, our results do not provide evidence for the contribution of CYP2D6 polymorphism to either drug response or CC concentrations.
Adult
;
Chromatography, High Pressure Liquid
;
Clomiphene/blood/metabolism/*therapeutic use
;
Cytochrome P-450 CYP2D6/*genetics
;
Estrogen Antagonists/analysis/metabolism/therapeutic use
;
Female
;
Genotype
;
Humans
;
Infertility/*drug therapy/genetics
;
Ovulation Induction
;
Phenotype
;
*Polymorphism, Genetic
;
Republic of Korea
;
Tandem Mass Spectrometry
10.Clinical Usefulness of Combined Cardiac Marker Testing with a Point-of-Care Device at the Emergency Department.
Misuk JI ; Hee Won MOON ; Seungman PARK ; Mina HUR ; Yeo Min YUN
Journal of Laboratory Medicine and Quality Assurance 2017;39(2):83-89
BACKGROUND: B-type natriuretic peptide (BNP) levels are elevated in various conditions unrelated to heart failure, such as acute coronary syndrome, and cardiac troponin (cTn) levels may also be elevated in several non-ischemic conditions. This study aimed to evaluate the clinical usefulness of combined cardiac marker testing (BNP and cTnI) with point-of-care devices in patients who presented to the emergency department (ED). METHODS: Two thousand six hundred and seventy-four consecutive patients who visited the ED from March to August 2013 were included in this study. Cardiac marker testing was performed using the Triage Cardio3 panel (Alere, USA). Electronic medical records were collected on August 2014. RESULTS: We found that 22.2% patients had elevated BNP and/or cTnI (12.8% with only elevated BNP, 4.4% with only elevated cTnI, and 5.0% with both elevations). Patients with elevations in both marker levels showed significantly higher admission rate (78.5% vs. 62.7%, P=0.006) and longer length of hospital stay (11 vs. 6 days, P=0.001) than those with only elevated cTnI. Patients with elevations in both marker levels also showed higher admission rate (78.5% vs. 67.3%, P=0.016) and higher BNP levels (430 vs. 194 pg/mL, P<0.001) than those with only elevated BNP. CONCLUSIONS: Concurrent elevation of BNP and cTnI may be associated with inferior clinical outcome and combined testing of cTnI and BNP levels with high sensitivity would provide important information for assisting management decisions at the ED.
Acute Coronary Syndrome
;
Electronic Health Records
;
Emergencies*
;
Emergency Service, Hospital*
;
Heart Failure
;
Humans
;
Length of Stay
;
Natriuretic Peptide, Brain
;
Point-of-Care Systems*
;
Triage
;
Troponin
;
Troponin I