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

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

Area Under Curve ; Biomarkers, Tumor ; Carcinoembryonic Antigen ; Carcinoma, Non-Small-Cell Lung ; Carcinoma, Squamous Cell ; Diagnosis ; Keratin-19 ; Lung Neoplasms ; Lung ; Medical Records ; Multivariate Analysis ; Retrospective Studies ; ROC Curve ; Sensitivity and Specificity

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

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

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

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

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

BACKGROUND: We evaluated the diagnostic performance of a newly developed Elecsys Anti-HCV II assay in Korean patients. METHODS: A total of 500 serum samples (400 antibody to hepatitis C virus [anti-HCV]-negative and 100 anti-HCV-positive samples) were collected after testing with Elecsys Anti-HCV assay (Roche Diagnostics, Germany). All the samples were tested for anti-HCV by using Vitros Anti-HCV (Ortho-Clinical Diagnostics, UK) and Elecsys Anti-HCV II (Elecsys II) (Roche Diagnostics, Germany) assays. Specimens that were found to be positive or negative in all the 3 assays were considered positive or negative for anti-HCV, respectively, and medical records of the patients, including results of previous HCV tests, were reviewed to determine the final results for anti-HCV when there were discrepancies among the results of the anti-HCV assays. RESULTS: Discrepancies between the results of the 3 anti-HCV assays were found for 4 of the 500 samples (0.8%). Sensitivity/specificity values for Elecsys II were 98.0%/100.0%, and the corresponding values for Elecsys and Vitros assays were 100.0%/100.0% and 100.0%/99.5%. Concordance rates between the results of any 2 of the 3 assays were equal or greater than 99.2%, with a kappa coefficient of 0.98 or greater (P < 0.0001). CONCLUSIONS: Sensitivities and specificities of the anti-HCV assays evaluated in this study were high enough for being used in clinical laboratories, and the results of the 3 assays showed good agreement. However, samples for which weak-positive results were obtained would need to be retested, considering the discrepancies between the anti-HCV assays.
Hepacivirus ; Hepatitis C Antibodies ; Humans ; Medical Records

STUDY DESIGN: A radiographic study of normal subjects. OBJECTIVES: To analyze sagittal spinal parameters according to the size of pelvic incidence (PI). SUMMARY OF LITERATURE REVIEW: There has been no previous study about the classification of spinopelvic parameters that has used a large cohort of asymptomatic older men with the same ethnic background as those in the current study. MATERIALS AND METHODS: We examined 160 males aged over 50 without disease, trauma, or history of operation on spine or lower extremities. Sagittal standing radiographs of the whole spine on 36-inch film were taken. Group 1 (n=30) had a PI of less than 40degrees. Group 2 (n=71) had PI between 40degrees and 50degrees, and group 3 (n=59) had a PI greater than 50degrees. Thoracic kyphosis, thoracolumbar kyphosis, lumbar lordosis, the vertebral slope of T12, sacral slope, and pelvic incidence were measured. The distances from the plumb line of C7, T12, and the lumbar apex to the posterosuperior corner of the sacrum were also measured. RESULTS: Subjects' average age was 64.1(53~83).Lumbar lordosis, sacral slope and pelvic tilt were all significantly increased in group 3. Thoracic kyphosis and the vertebral slope of T12 were not different between groups. The distances from the plumb line of C7, T12, and the lumbar apex to the posterosuperior corner of the sacrum were significantly translated anteriorly in group 3. CONCLUSIONS: Group 3, who had the largest PI, demonstrated the largest lumbar lordosis and the most forward transition of trunk. However there were no differences in thoracic kyphosis and the vertebral slope of T12 among the three groups.
Aged ; Animals ; Cohort Studies ; Humans ; Incidence ; Kyphosis ; Lordosis ; Lower Extremity ; Male ; Pelvis ; Sacrum ; Spine