BACKGROUND: Serum separator tubes were introduced 25 years ago and are widely used in the clinical laboratory for collection of blood. Recently, the plastic serum separator tube has become available for blood collection for lightening and flexibility and suitability for automation. However few studies have been reported on stability of the common analytes in this tube. METHODS: We evaluated the concentrations of seventeencommonly ordered analytes: aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total protein, albumin, sodium, chloride, calcium, phosphorus, triglyceride, low density lipoprotein (LDL)-cholesterol, potassium, uric acid, blood urea nitrogen (BUN), total cholesterol, glucose, creatinine in sera separated in plain glass tubes (no gel) and in sera separated in the plastic Greiner Bio-One Vacuette tubes containing serum separator gel (Greiner Bio-One, Kremsm?nster, Austria) by Toshiba 200-FR Neo. RESULTS: Results were analyzed using two-tailed paired t-tests and Bland-Altman plots. Results from 9 common analytes (glucose, total cholesterol, BUN, potassium, LDL-cholesterol, inorganic phosphorus, calcium, sodium, chloride) were statistically different between glass tube and plastic Greiner Bio-One Vacuette tube, but the differences were not considered to be clinically significant. CONCLUSIONS: We conclude that the plastic Greiner Bio-One Vacuette tubes are suitable for collection of blood and storage of serum for common analytes.
Alanine Transaminase ; Alkaline Phosphatase ; Aspartate Aminotransferases ; Automation ; Blood Urea Nitrogen ; Calcium ; Calcium Chloride ; Chemistry, Clinical* ; Cholesterol ; Creatinine ; Glass* ; Glucose ; Lipoproteins ; Phosphorus ; Plastics ; Pliability ; Potassium ; Sodium ; Triglycerides ; Uric Acid

BACKGROUND: There is room for doubt that the reference intervals currently used in many hospitals or health institutions in Korea are appropriate, because some scientists do not agree that the selections of reference individuals were valid universally. If we adopt the inappropriate reference intervals in the decision making of examinees' health status, we are liable to lead to false-negatives or false-positives. METHODS: We selected 555 healthy and 2,134 unhealthy adult samples who took medical check-up at an institution between 2000 and 2004 through semi-stratified random sampling method. Disease groups were divided into 7 subgroups: hepatic, gastrointestinal, obesity, circulatory, endocrine, urogenital and others. RESULTS: Through parametric and non-parametric methods, we produced new reference intervals and compared the newly developed intervals with current ones. Some reference values should be adjusted newly; ALT-male < or =33 IU/L, ALT-female < or =22 IU/L, AST < or =28 IU/L, cholesterol < or =198 mg/dL, triglyceride-male < or =172 mg/dL, triglyceride-female < or =133 mg/dL, fasting blood sugar 65-101 mg/dL. CONCLUSIONS: In order to reduce the rate of false-positives or false-negatives, we suggest that reference ranges of some items might be reestablished or adjusted according to gender through the further studies on current reference ranges.
Adult* ; Blood Glucose ; Cholesterol ; Decision Making ; Fasting ; Humans ; Korea ; Obesity ; Reference Values*

BACKGROUND Coagulation assays can be easily affected by preanalytical variables, including the factors associated with the blood collection tube. Recently the Sekisui Trank Insepack (Sekisui Chemical Co., Ltd, Osaka, Japan; Insepack) blood collection tubes were introduced into Korea. The aim of this study was to compare the results of routine coagulation assays using the Insepack with those using BD Vacutainer (BD, Franklin Lakes, NJ, USA; Vacutainer) tubes, which are most widely used in Korea. METHODS: Paired blood samples from 64 patients were drawn into Insepack and Vacutainer 3.2% citrate tubes. The results of prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, and fibrin/fibrinogen degradation product (FDP) were determined in parallel. RESULTS: No statistically significant differences were observed between Insepack and Vacutainer tubes for PT, fibrinogen, and FDP tests. For APTT which showed the significant differences between the results in the two tubes the mean difference was small (0.8 seconds), and it was not considered clinically significant. CONCLUSIONS: The results of this study suggest that Insepack tubes can be used in place of Vacutainer tubes for routine coagulation assays.
Citric Acid* ; Fibrinogen ; Humans ; Japan ; Korea ; Lakes ; Partial Thromboplastin Time ; Plastics* ; Prothrombin Time

BACKGROUND: Recent advances of hematology analyzers have improved performance of leukocyte differential counts and have reduced work load of clinical hematology laboratories. We evaluated CELL-DYN Sapphire (Abbott Diagnostics, Santa Clara, CA, USA) performance on leukocyte differential counts according to Clinical and Laboratory Standards Institute (CLSI) document H20-A. METHODS: We evaluated imprecision (short term imprecision from duplication of 147 patients' sample and long term imprecision from three level commercial controls) and accuracy (n=462) of leukocyte differential counts of CELL-DYN Sapphire and compared with those of Sysmex XE-2100 (TOA Medical Electronics Co., Kobe, Japan), ADVIA 120 (Bayer Diagnostics, Tarrytown, NY, USA) and Beckman Coulter LH 750 (Beckman Coulter, Miami, FL, USA). RESULTS: The imprecision of CELL-DYN Sapphire for neutrophils and lymphocytes differentials was low with coefficients of variation (CV) from 1.4 to 6.2%, but the imprecision for basophils was high with CV from 34.7 to 79.6%. The correlation with manual count was good in samples without flags (n=314), with the exception of basophils (r: neutrophils, 0.921; lymphocytes, 0.921; monocytes, 0.653; eosinophils, 0.869; basophils 0.272). The correlation with other hematology analyzers was high except basophils (r: neutrophils, 0.969-0.986; lymphocytes, 0.986-0.990; monocytes, 0.787-0.887; eosinophils, 0.881-0.962; basophils 0.086-0.327). CONCLUSION: The performance on leukocyte differential counts of CELL-DYN Sapphire is comparable to Sysmex XE-2100, ADVIA 120 and Beckman Coulter LH 750. In regards of enumeration of basophils, the comparison with manual counts and other hematology analyzers shows poor agreement.
Aluminum Oxide* ; Basophils ; Electronics, Medical ; Eosinophils ; Hematology* ; Leukocytes* ; Lymphocytes ; Monocytes ; Neutrophils

BACKGROUND: A new HPV DNA chip test for the infection of 22 HPV genotypes was recently developed in Korea. This test using PCR and hybridization is inherently vulnerable to contamination, and to subjective qualitative test judgment. Hence, it warrants rigorous quality assurance measures. The authors would like to share operational experiences of the guidelines developed at Catholic University Holy Family Hospital. METHODS: Our quality assurance system of HPV DNA chip test comprised external quality controls, inter-laboratory proficiency tests, and internal quality controls. For the external quality controls, we analyzed the results of four years of participation in the quality assurance program by the Korean Laboratory Medicine Quality Assurance Association. The inter-laboratory proficiency tests with BioMedLab were done by single blind tests using patients' samples showing negative, single and multiple infections. The internal quality control dealt with methods to prevent contamination, and with reproduction tests. RESULTS: The results from the external quality control revealed consistency with HPV-16 in 7 trials during 4 years. The inter-laboratory proficiency tests showed a 82% consistency rate, 10 cases of inconsistency showing positive or negative mismatches, and 8 cases of genotypic mismatches. The 10 mismatches were due to the weak laser power of the scanner used in BioMedLab. The genotypic contamination rate found in the internal quality control was 3.3%, and the contamination by HPV-35 with low incidence rate was often observed. The contamination was not easily eliminated by re-tests from hybridization, but 80% of it was removed when re-tested with the remaining samples. The fluorescence intensity was not reproducible nor provide quantitative or semi-quantitative information. CONCLUSIONS: For quality assurance regarding HPV DNA chip tests, we suggest the following be implemented: technical quality control to rule out the false-negative and false-positive during PCR and hybridization; scanner quality control to prevent reading errors; and inter-laboratory proficiency tests.
DNA* ; Fluorescence ; Genotype ; Human papillomavirus 16 ; Humans ; Incidence ; Judgment ; Korea ; Oligonucleotide Array Sequence Analysis* ; Polymerase Chain Reaction ; Quality Control ; Reproduction

BACKGROUND: The serologic tests for syphilis infection have been performed manually, but the procedures are time-consuming and interpretations may be subjective. Recently, automated assays were developed for rapid and efficient testing for syphilis infection. In this study, we evaluated the performances of IMMUNOTICLES Auto3 RPR and Auto3TP (A&T Corporation, Japan) using latex agglutination turbidimetry method. METHODS: Using 236 serum samples referred for syphilis at Ewha Womans University, Mokdong Hospital, between March 2004 and April 2007, we evaluated precision, linearity, detection limit and compared with the results of manual serologic tests, RPR (RPR card test, ASAN Pharmaceutical, Korea) and TPHA (ASAN-TPHA, ASAN Pharmaceutical). RESULTS: The within-run and between day precisions of Auto3RPR and Auto3TP were from 2.1% to 4.8%. The linearity was good up to 5.0 RU for Auto3RPR and to 250 TU for Auto3TP. Agreement of Auto3RPR with RPR was 65.7% (155/236) and 32.6% of patients (77/236) were RPR positive and Auto3RPR negative. RPR titers were less than 1:8 in 99% of these discrepant samples (76/77) and 65% (50/77) were latent infection and the others were false positive (32%, 27/77). Agreement of Auto3TP with TPHA was 97.1%. CONCLUSIONS: IMMUNOTICLES Auto3RPR and Auto3TP may be useful for rapid and efficient testing for syphilis. However, discrepant results were present in patients with low titer RPR positivity and method of reporting shoud be considered in individual clinical situation. In addition, linear range was not wide and further study is needed for reporting of quantitative results.
Agglutination ; Automation ; Chungcheongnam-do ; Female ; Humans ; Latex ; Limit of Detection ; Nephelometry and Turbidimetry ; Serologic Tests ; Syphilis*

BACKGROUND: The tests for the anti-rubella antibodies are important in early pregnancies because the risk of congenital anomaly should be considered depending on the results. We would like to evaluate analytical performance of Roche Modular Analytics E170 (Roche Diagnostics, Mannheim, Germany; E170) for anti-rubella antibodies. METHODS: For the comparison studies, a total of 436 sera from pregnant or fertile women was used for the detection of anti-rubella antibodies by E170 and VIDAS analyzer. The precision of E170 for serum anti-rubella IgM and IgG were also evaluated. RESULTS: In the precision study, within-run and total CV of anti-rubella IgM and IgG were below 5%. In the comparison study, the agreement of E170 with VIDAS was above 90%. CONCLUSIONS: The E170 showed a satisfactory precision for anti-rubella antibodies and a high level of concordance with VIDAS. Therefore, E170 would be useful as a routine immunoassay analyzer for measuring anti-rubella IgM and IgG antibodies.
Antibodies* ; Female ; Germany ; Humans ; Immunoassay ; Immunoglobulin G* ; Immunoglobulin M* ; Pregnancy

BACKGROUND: Cefoxitin, a cephamycin-type antibiotic, is known to be superior to oxacillin in predicting the presence of mecA gene because it serves as a very potent inducer of mecA regulatory system. We used a cefoxitin disk diffusion methods for detection of methicillin-resistant Staphylococcus aureus (MRSA), and compared it with the conventional methods. METHODS: For 50 MRSA and 50 methicillin susceptible S. aureus confirmed by mecA and femA gene PCR, oxacillin, cefoxitin, and moxalactam disk diffusion methods, oxacillin and cefoxitin E-tests, Vitek 2 and Microscan Walkaway antibiotics susceptibility tests, and PBP2a latex agglutination test were performed. The sensitivity and specificity of each method were evaluated. RESULTS: The sensitivities of oxacillin disk diffusion method and E-test were 96%. The sensitivities of cefoxitin and moxalactam disk diffusion method, cefoxitin E-test, Vitek 2, Microscan Walkaway, PBP2a latex agglutination test were 100%. The specificities were 100% for all the methods used. CONCLUSIONS: It may be considered that both the cefoxitin- and moxalactam disk diffusion methods are effective and excellent screening methods for the detection of MRSA in clinical laboratory routinely.
Anti-Bacterial Agents ; Cefoxitin ; Diffusion ; Latex Fixation Tests ; Mass Screening ; Methicillin ; Methicillin Resistance* ; Methicillin-Resistant Staphylococcus aureus* ; Moxalactam ; Oxacillin ; Polymerase Chain Reaction ; Sensitivity and Specificity

BACKGROUND: Many modern chemistry analyzers are open systems and they can use reagents other than those supplied by the manufacturer of the analyzer. There are many generic reagents for use in open systems. The objective of this study was to evaluate the analytical performance of the BD Lab reagents (BD Lab co., Korea) which were generic reagents. METHODS: Sixteen kinds of reagents of total protein, albumin, blood urea nitrogen (BUN), creatinine, glucose, uric acid, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, alkaline phosphatase (ALP), lactate dehydrogenase (LD), gamma glutamyl transferase (GGT), calcium, inorganic phosphorus, total cholesterol, triglycerides were tested for precision, linearity and correlation according to the NCCLS guidelines (EP5-A, EP6-A, EP9-A2). Toshiba 200-FR Neo (Toshiba Medical Systems Co., Japan) was used in this evaluation. RESULTS: All reagents showed acceptable precision with total coefficients of variation less than 7%. Comparison of BD Lab reagents with the current reagents by regression analysis resulted in slopes ranging from 0.86 to 1.06 and correlation coefficients more than 0.975. Fifteen of sixteen reagents showed good linearity in broad range. CONCLUSIONS: BD Lab reagents showed good precision, linearity, and correlation. Therefore, we conclude that the BD Lab reagents can be an alternative of currently used reagents in chemistry analyzers.
Alanine Transaminase ; Alkaline Phosphatase ; Aspartate Aminotransferases ; Bilirubin ; Blood Urea Nitrogen ; Calcium ; Chemistry* ; Cholesterol ; Creatinine ; Glucose ; Indicators and Reagents* ; L-Lactate Dehydrogenase ; Phosphorus ; Transferases ; Triglycerides ; Uric Acid

We have evaluated the performance of a recently developed immunoassay analyzer, ADVIA Centaur XPT (Siemens, Germany). Precision, linearity, and comparison studies were performed according to the CLSI guidelines. The test items evaluated were ferritin, folate, human epidermal growth factor receptor 2/neu, homocysteine, vitamin B₁₂, B-type natriuretic peptide, creatine kinase–myocardial band, myoglobin, procalcitonin, troponin I. Bio-Rad control materials, linearity materials, and patients' samples were used for the evaluation. For the correlation study, ADVIA Centaur XP (Siemens) were used as comparative methods. The total coefficients of variations (CVs) of the analytes were between 2.5% and 7.0%. The results of linearity evaluation were also acceptable for the range tested. Correlations with comparative methods were good. The overall analytical performance of ADVIA Centaur XPT is acceptable for the immunology analyzer. Therefore, ADVIA Centaur XPT is expected to be widely used.
Allergy and Immunology ; Creatine ; Ferritins ; Folic Acid ; Homocysteine ; Humans ; Immunoassay ; Myoglobin ; Natriuretic Peptide, Brain ; Receptor, Epidermal Growth Factor ; Statistics as Topic ; Troponin I ; Vitamins