1.Comparison of the QIAGEN artus HBV QS-RGQ Assay With the Roche COBAS AmpliPrep/COBAS TaqMan HBV Assay for Quantifying Viral DNA in Sera of Chronic Hepatitis B Patients.
Mi Soon HAN ; Yongjung PARK ; Hyunjin NAH ; Hyon Suk KIM
Annals of Laboratory Medicine 2017;37(3):248-253
BACKGROUND: Hepatitis B virus DNA quantification is essential for managing chronic hepatitis B (CHB). We compared the performance of artus HBV QS-RGQ (QIAGEN GmbH, Germany) and CAP/CTM v2.0 HBV assays (Roche Molecular Diagnostics, USA) in CHB patients. METHODS: A comparative evaluation between two assays was performed with 508 clinical serum samples. Precision, linearity, and the limit of detection (LOD) of QS-RGQ assay was evaluated by using the WHO standard 97/750 and clinical samples. RESULTS: Detection rates and viral loads as determined QS-RGQ assay were significantly lower than those from the CAP/CTM v2.0 assay (52.8% vs 60.6%; 3.55±1.77 IU/mL vs 4.18±1.89 IU/mL, P<0.0001). The kappa coefficient between qualitative results was 0.79 (95% confidence interval, 0.74 to 0.85). Bland-Altman plot found a mean difference of (QS-RGQ − CAP/CTM v2.0)=−0.63 log₁₀ IU/mL (95% limit of agreement, −1.48 to 0.22). Repeatability and total imprecision (% CV) of the QS-RGQ assay were 1.0% and 1.1% at 2,000 IU/mL, and 0.7% and 1.4% at 20,000 IU/mL, respectively. Linearity of this assay ranged from 31.6 to 1.0±10⁷ IU/mL, and the LOD was 2.95 IU/mL. CONCLUSIONS: The artus HBV QS-RGQ assay showed good performance but significantly decreased detection rate and viral load compared with CAP/CTM v2.0 assays. This assay recommends using plasma; however, we used stored serum because of the retrospective study design. Usually HBV DNA quantification is performed in plasma or serum, but sample type and clinical relevance of quantitative values should be considered when determining the clinical application of this reagent.
DNA
;
DNA, Viral*
;
Hepatitis B virus
;
Hepatitis B, Chronic*
;
Hepatitis, Chronic*
;
Humans
;
Limit of Detection
;
Pathology, Molecular
;
Plasma
;
Retrospective Studies
;
Viral Load
2.Evaluation of the UniCel(TM) DxI 800 Immunoassay Analyzer in Measuring Five Tumor Markers.
Younhee PARK ; Yongjung PARK ; Jungyong PARK ; Hyon Suk KIM
Yonsei Medical Journal 2012;53(3):557-564
PURPOSE: Tumor marker concentrations in a given specimen measured by different analyzers vary according to assay methods, epitopes for antibodies used, and reagent specificities. Although great effort in quality assessment has been instituted, discrepancies among results from different analyzers are still present. We evaluated the assay performance of the UniCel(TM) DxI 800 automated analyzer in measuring the alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 125, CA 15-3 and CA 19-9 tumor markers. MATERIALS AND METHODS: The linearity and precision performance of the five tumor marker assays were evaluated, and concentrations of the respective markers as measured by DxI were compared to those measured by other conventional analyzers (ADVIA Centaur(TM) and Vitros(TM) ECi) using 200 specimens collected from 100 healthy persons and 100 patients with respective cancers. RESULTS: The linear fits for all five tumor markers were statistically acceptable (F=4648 for AFP, F=15846 for CEA, F=6445 for CA 125, F=2285 for CA 15-3, F=7459 for CA 19-9; p<0.0001 for all). The imprecision of each tumor marker assay was less than 5% coefficient of variation, except for low and high concentrations of AFP. The results from UniCel(TM) DxI 800 were highly correlated with those from other analyzers. CONCLUSION: Our results demonstrate that UniCel(TM) DxI 800 has good linearity and precision performance for the tumor markers assayed in this study. However, there were discrepancies between assaying methods. Efforts to standardize tumor marker assays should be undertaken, and the redetermination of cut-off levels is necessary when developing methods of analyzing tumor markers.
CA-125 Antigen/blood
;
CA-19-9 Antigen/blood
;
Carcinoembryonic Antigen/blood
;
Humans
;
Immunoassay/*instrumentation/*methods
;
Tumor Markers, Biological/*blood
;
alpha-Fetoproteins/metabolism
4.Re-establishment of Blood Ordering Practice for Elective Surgery.
Yongjung PARK ; Moon Jung KIM ; Jin Ju KIM ; Sinyoung KIM ; Jong Hoon KIM ; Hyun Ok KIM
Korean Journal of Blood Transfusion 2008;19(3):171-179
BACKGROUND: The amount of blood components "on hold" preoperatively is usually determined by the surgeon's experiences or habits, and is often an amount in excess of the amount actually transfused. This method could diminish the effective use of blood components and result in an excessive workload for the blood bank, a shortage of blood products, and an increase in the quantity of discarded blood products. We quantified the amount of RBC components transfused during surgeries to establish the maximal surgical blood order schedule (MSBOS). METHODS: We analyzed the number of RBC component units transfused to patients >17 years of age who underwent elective surgeries performed at a university hospital between November 2005 and February 2007. RESULTS: There were 48,007 elective surgeries performed during the investigated period. The Departments of Surgery, Ophthalmology, Otolaryngology, and Urology carried out 8,317, 7,407, 5,928, and 5,268 surgical cases, respectively. The MSBOS values for 60 types of surgeries categorized into 7 surgical fields are listed. CONCLUSION: In the current study, we analyzed a greater number of surgical cases than previous studies in an effort to generate accurate and practical data. The mean amount of transfused RBC units was less in most types of surgeries compared to previous studies; this finding is presumed to be the result of improvements in surgical techniques and advances in medical science. A regular and comprehensive revision of the MSBOS is required to correspond to the changes in the medical environment and the shifting characteristics of patients, and to maximize the utility of blood products. A committee to supervise transfusion practices is also essential to coordinate different policies of the laboratory, surgical,and anesthesiology departments.
Anesthesiology
;
Appointments and Schedules
;
Blood Banks
;
Humans
;
Ophthalmology
;
Otolaryngology
;
Urology
5.Variations in Sagittal Spinopelvic Parameters According to the Lumbar Spinal Morphology in Healthy Korean Young Men.
Young Jun AHN ; Young Bae KIM ; Kyu Bok KANG ; Seung Won LEE ; Yongjung KIM
Journal of Korean Society of Spine Surgery 2010;17(2):66-73
STUDY DESIGN: This is a prospective radiographic study. OBJECTIVES: We wanted to describe and quantify the common variations in the sagittal lumbar spine. SUMMARY OF THE LITERATURE REVIEW: No previous study of the spinopelvic parameters with a large cohort of asymptomatic young men was performed on subjects with the same ethnic background. MATERIALS AND METHODS: 166 young males without disease, trauma or a history of operation on the spine or lower extremities were included. The sagittal standing radiographs of the whole spine on 36 inch film were taken. The distances from the plumb line of C7, T12, the lumbar apex and the bicoxofemoral head to the posterosuperior corner of the sacrum were measured. Thoracic kyphosis, thoracolumbar kyphosis, lumbar lordosis, the segmental vertebral slopes, the sacral slope and the pelvic incidence were measured. Groups 1 and 2 were classified by having a sacral slope less than 35degrees (group 1: apex below L4, group 2: above L4). Group 3 had a sacral slope between 35degrees and 45degrees, and group 4 had a sacral slope greater than 45degrees. RESULTS: The average age was 21.8 years (range: 19~26 years). Group 1 contained 37 cases, group 2 had 44, group 3 had 62 and group 4 had 23. Thoracolumbar kyphosis was significantly increased in group 1 and lumbar lordosis and pelvic incidence were increased in groups 3 and 4. Thoracic kyphosis and the vertebral slope of T12 did not demonstrate any difference between the groups. CONCLUSION: The sagittal spinopelvic parameters showed significant changes according to the morphology of the lower lumbar spine. Understanding the patterns of variation in the spinopelvic parameters may help surgeons to plan treatment for various spinal lesions.
Animals
;
Cohort Studies
;
Head
;
Humans
;
Incidence
;
Kyphosis
;
Lordosis
;
Lower Extremity
;
Male
;
Prospective Studies
;
Sacrum
;
Spine
6.Evaluation of the Performance of an Adiponectin ELISA-based Test and Establishing Serum Adiponectin Reference Intervals for Korean Population.
Yongjung PARK ; Young Ran KIM ; Hyon Suk KIM
Laboratory Medicine Online 2013;3(4):242-252
BACKGROUND: Adiponectin is a plasma protein secreted by adipose tissues and low serum adiponectin concentration has been reported to be associated with insulin resistance and metabolic syndrome (MS). We evaluated the performance of an ELISA-based assay for measuring serum adiponectin levels and established reference intervals of adiponectin for Korean population. METHODS: Laboratory performance, including precision and linearity, of the AdipoMark Human Adiponectin ELISA kit (Mesdia Co., Korea) was assessed. Reference intervals of adiponectin concentration were determined after evaluation of 1200 subjects with no history of MS. Adiponectin was also measured in 100 patients with MS. RESULTS: The mean concentrations of serum samples tested for precision evaluation were 6.66, 12.61, and 23.42 microg/mL: the ELISA showed total imprecision of 13.6%, 9.3%, and 10.5% CV for the respective concentrations. The assay demonstrated linear responses in the range of 1.8-29.9 microg/mL serum adiponectin levels. The 95% reference intervals for Korean population were 3.6-19.2 microg/mL for men and 4.5-34.2 microg/mL for women. ROC-area under the curve values of adiponectin for the diagnosis of MS were 0.85 for men and 0.83 for women. Low adiponectin level was independently associated with MS in the multivariate analysis. CONCLUSIONS: The adiponectin quantitation assay evaluated in this study showed acceptable laboratory and clinical performances in an ELISA platform. To meet the ever-increasing demand for a reliable assay for measuring adiponectin levels in the study of various metabolic diseases, this assay could be further improved by the automation of the platform.
Adiponectin
;
Automation
;
Enzyme-Linked Immunosorbent Assay
;
Female
;
Humans
;
Insulin Resistance
;
Male
;
Metabolic Diseases
;
Plasma
7.Evaluating the Appropriateness of a Single Unit Transfusion.
Yongjung PARK ; Younhee PARK ; Yangsoon LEE ; Eun Jung BAEK ; Sinyoung KIM ; Hyun Ok KIM
Korean Journal of Blood Transfusion 2007;18(3):177-187
BACKGROUND: The domestic quantity of blood components consumed has been decreasing since 2002, but the rate of a single unit RBC transfusion (SUT) has been on the increase. In the past, a SUT was regarded as an uncesssary procedure, but currently is considered as an effective method to maintain a minimal hemoglobin concentration for physiological needs. We investigated the actual conditions of a SUT. METHODS: We analyzed 800 cases of SUTs performed at a tertiary care university hospital between March 2006 March and February 2007. The subjects of the study were divided into a surgical group (n=561) and medical group (n=239) for the purpose of RBC unit usage and were analyzed by groups and ordering departments, with an analysis of the pre and post-transfusion hemoglobin concentration and hematocrit values. The distribution according to the pre and post-transfusion hemoglobin ranges were calculated. RESULTS: The mean hemoglobin concentration increment of the surgical group was significantly lower than that of the medical group (P<0.0001) and the mean pre and post-transfusion hemoglobin concentrations of the medical group were lower than that of the surgical group (P<0.0001). Approximately 26% cases of the SUTs performed in the surgical group were appropriate, based on a post-transfusion hemoglobin concentration below 10 g/dL. In the medical group, about 75% of the SUTs were appropriate based on a pre-transfusion hemoglobin concentration below 9 g/dL. CONCLUSION: Most transfusions are decided based on various clinical situations and opinions of the clinicians. Therefore, continuous evaluation of the appropriateness of transfusion is necessary. In our study, the appropriateness of a SUT was estimated indirectly based on the pre and post-transfusion hemoglobin concentration. Consequently, policies and strategies for performing asingle unit RBC transfusion are required.
Hematocrit
;
Tertiary Healthcare
8.A Mid-Term Follow-Up Result of Spinopelvic Fixation Using Iliac Screws for Lumbosacral Fusion.
Seung Jae HYUN ; Seung Chul RHIM ; Yongjung J KIM ; Young Bae KIM
Journal of Korean Neurosurgical Society 2010;48(4):347-353
OBJECTIVE: Iliac screw fixation has been used to prevent premature loosening of sacral fixation and to provide more rigid fixation of the sacropelvic unit. We describe our technique for iliac screw placement and review our experience with this technique. METHODS: Thirteen consecutive patients who underwent spinopelvic fixation using iliac screws were enrolled. The indications for spinopelvic fixation included long segment fusions for spinal deformity and post-operative flat-back syndrome, symptomatic pseudoarthrosis of previous lumbosacral fusions, high-grade lumbosacral spondylolisthesis, lumbosacral tumors, and sacral fractures. Radiographic outcomes were assessed using plain radiographs, and computed tomographic scans. Clinical outcomes were assessed using the Oswestry Disability Index (ODI) and questionnaire about buttock pain. RESULTS: The median follow-up period was 33 months (range, 13-54 months). Radiographic fusion across the lumbosacral junction was obtained in all 13 patients. The average pre- and post-operative ODI scores were 40.0 and 17.5, respectively. The questionnaire for buttock pain revealed the following: 9 patients (69%) perceived improvement; 3 patients (23%) reported no change; and 1 patient (7.6%) had aggravation of pain. Two patients complained of prominence of the iliac hardware. The complications included one violation of the greater sciatic notch and one deep wound infection. CONCLUSION: Iliac screw fixation is a safe and valuable technique that provides added structural support to S1 screws in long-segment spinal fusions. Iliac screw fixation is an extensive surgical procedure with potential complications, but high success rates can be achieved when it is performed systematically and in appropriately selected patients.
Buttocks
;
Congenital Abnormalities
;
Follow-Up Studies
;
Humans
;
Pseudarthrosis
;
Surveys and Questionnaires
;
Spinal Fusion
;
Spondylolisthesis
;
Wound Infection
9.Identification of Adenovirus, Influenza Virus, Parainfluenza Virus, and Respiratory Syncytial Virus by Two Kinds of Multiplex Polymerase Chain Reaction (PCR) and a Shell Vial Culture in Pediatric Patients with Viral Pneumonia.
Jong Han LEE ; Jin Kyong CHUN ; Dong Soo KIM ; Yongjung PARK ; Jong Rak CHOI ; Hyon Suk KIM
Yonsei Medical Journal 2010;51(5):761-767
PURPOSE: Early identification of causative agents in lower respiratory infection of pediatric patients can reduce morbidity and prevent an overuse of antimicrobials. Two kinds of multiplex polymerase chain reaction (PCR) and a commercial shell vial viral culture were performed to identify causative agents in pediatric patients. MATERIALS AND METHODS: Nasopharyngeal aspirates of 220 children diagnosed with viral pneumonia were obtained. Two kinds of multiplex PCR (Seeplextrade mark RV detection kit, and Labopasstrade mark RV detection kit), and a shell vial culture by R-Mix were performed. RESULTS: Positive samples from 220 total samples by two multiplex PCRs were 52.7% and 46.4%, respectively. We also cultured 103 samples that showed positive results of the adenovirus, influenza virus, parainfluenza virus, and respiratory syncytial virus (RSV) by two multiplex PCR. The RSV was most frequently detected in 53.0% (Seeplex) and 51.7% (Labopass) of patients. The detection rate of adenovirus (AdV) was 10.3% and 12.1%, influenza virus (IFV) A and B was 12.5% and 3.4%, and parainfluenza virus (PIFV) 1, 2, and 3 were 2.9% and 2.6%. Shell vial cultures showed concordant results with each multiplex PCR by 96.1% and 77.7%, respectively. Sequencing results were 90% consistent with multiplex PCR. CONCLUSION: Multiplex PCR showed more positivity than the shell vial culture and it can be an effective primary test. Other complementary efforts such as viral cultures and sequencing analysis could be considered, according to clinical and laboratory conditions.
Adenoviridae/genetics/*isolation & purification
;
Child
;
Child, Preschool
;
Female
;
Humans
;
Infant
;
Infant, Newborn
;
Male
;
Orthomyxoviridae/genetics/*isolation & purification
;
Pneumonia, Viral/*virology
;
Polymerase Chain Reaction/*methods
;
Respiratory Syncytial Viruses/genetics/*isolation & purification
;
Respirovirus/genetics/*isolation & purification
10.Resolution of Ambiguous HLA Genotyping in Korean by Multi-Group-Specific Sequence-Based Typing.
Yongjung PARK ; Cha Eun YOON ; Oh Joong KWON ; Yu Seun KIM ; Hyon Suk KIM
Yonsei Medical Journal 2014;55(4):1005-1013
PURPOSE: To evaluate a multi-group-specific sequence-based typing (SBT) method for resolving ambiguous results from human leukocyte antigen (HLA) genotyping. MATERIALS AND METHODS: A total of 50 samples that showed ambiguous genotypes for at least two HLA loci from HLA-A, -B, -C and -DRB1 by the conventional SBT assay were evaluated using a new SBT test, the AVITA plus assay. The most likely HLA genotypes for the respective samples considering allele frequencies in Korean were concordant between the AVITA and conventional SBT assays. RESULTS: An average of 3.3 loci among the HLA-A, -B, -C and -DRB1 loci per sample gave results with two or more possible allele combinations with the conventional SBT, and 48 (96.0%) out of 50 showed reduced numbers of possible genotypes for at least one HLA locus with the AVITA. A total of 41, 43, 42, and 38 cases among the 50 samples showed ambiguous results for HLA-A, -B, -C, and -DRB1 typing by the conventional SBT, respectively. The average numbers of possible allele combinations for the respective four HLA loci were 8.2, 6.7, 5.9, and 3.2, and they were reduced to 1.5, 2.2, 4.4, and 1.8, respectively, by the AVITA. Ambiguity was resolved by the AVITA in 33 (80.5%), 31 (72.1%), 17 (40.5%) and 28 (73.7%) samples among the ambiguous cases from the conventional SBT for HLA-A, -B, -C, and -DRB1 typing, respectively. CONCLUSION: The multi-group-specific SBT method considerably reduced the number of ambiguous results, and thus may be useful for accurate HLA typing in clinical laboratories.
Asian Continental Ancestry Group/genetics
;
Base Sequence
;
Gene Frequency/genetics
;
Genotype
;
HLA Antigens/*genetics
;
Histocompatibility Testing
;
Humans
;
Polymerase Chain Reaction