Performance Evaluation of the DxC 700 AU Chemistry Analyzer in Hemoglobin A1c Measurement

Background@#Accurate measurement of glycated hemoglobin (HbA1c) is crucial for a diabetes diagnosis and subsequent patient management. The detection method and presence of variant Hb can interfere with HbA1c measurements. We evaluated the HbA1c-measuring performance of the DxC 700 AU (Beckman Coulter, Brea, CA, USA) immunoassay-based device in comparison with another immunoassay device and the reference method. @*Methods@#A total of 120 normal and 14 variant Hb samples were analyzed using the Cobas c 513 (Roche Diagnostics, Mannheim, Germany) and DxC 700 AU analyzers. Variant Hb samples were also analyzed using the reference method, along with 20 normal samples. The accuracy, precision, linearity, and carryover were determined. @*Results@#DxC 700 AU results strongly correlated with those of Cobas c 513 and exhibited accuracy in comparison with the reference method. The within-run, between-run, between-day, and total imprecision (%CV) values for the low- and high-concentration control materials were below 2%. The results of DxC 700 AU were linear over a wide HbA1c range (3.39%–18.30%). Although DxC 700 AU performed well in the presence of variant Hb, the HbA1c concentration was underestimated in the presence of fetal Hb. The possibility of interference from a high HbH proportion could not be ruled out. @*Conclusions@#The overall analytical performance of DxC 700 AU was acceptable. The device is accurate, precise, and linear over a wide HbA1c concentration range. Although DxC 700 AU results highly correlated with those of Cobas c 513, caution should be exercised in cases of high HbF and HbH concentrations.

Associations of LDL Cholesterol, Non-HDL Cholesterol, and Apolipoprotein B With Cardiovascular Disease Occurrence in Adults: Korean Genome and Epidemiology Study

Background@#Despite the superiority of non-HDL cholesterol (non-HDL-C) and apolipoprotein B (ApoB) as lipid markers for atherosclerotic cardiovascular disease (ASCVD), these are only suitable as secondary markers. We compared LDL cholesterol (LDL-C), non-HDL-C, and ApoB concentrations with respect to the occurrence of cardiovascular disease in adults enrolled in the Korean Genome and Epidemiology Study (KoGES). @*Methods@#We used information on age; sex; medical history; family history of ASCVD; current lipid-lowering therapy; current smoking status; and creatinine, total cholesterol, HDL-C, LDL-C, triglyceride, and ApoB concentrations from 5,872 KoGES participants without ASCVD. New ASCVD development was monitored during the 8-year follow-up period. Adjusted hazard ratios (aHRs) for ASCVD of LDL-C, non-HDL-C, and ApoB concentrations were calculated based on the multivariate Cox regression analyses. The participants were also grouped as low and high according to the median values for each lipid marker, and calculated aHRs of each group combined by two lipid makers. @*Results@#ApoB showed the highest aHR per 1-SD for ASCVD (1.26; 95% confidence interval [CI], 1.11–1.43), followed by non-HDL-C (1.25; 95% CI, 1.11–1.41) and LDL-C (1.20; 95% CI, 1.06–1.37). The group with low LDL-C and high ApoB concentrations had a significantly higher aHR for ASCVD (1.61; 95% CI, 1.05–2.48) compared to the reference group values (low LDL-C and low ApoB concentrations). The aHR for the group with high LDL-C and low ApoB concentrations was not significant (1.30; 95% CI, 0.79–2.16). @*Conclusions@#ApoB, non-HDL-C, and LDL-C are independent risk factors for ASCVD. Increases in the aHR per 1-SD for ASCVD were more strongly affected by ApoB, followed by non-HDL-C and LDL-C. Participants with low LDL-C and high ApoB concentrations showed increased ASCVD risk. For individuals with ASCVD risk factors, even those presenting normal LDL-C concentrations, measuring ApoB concentrations can provide useful information for better evaluation of ASCVD risk.

A Disintegrin and Metalloproteinase 8 as a Potential Blood Biomarker for Early Diagnosis of Gastric Cancer

PURPOSE: We aimed to evaluate the clinical significance of a disintegrin and metalloproteinase 8 (ADAM 8) as a potential blood biomarker for gastric cancer (GC). MATERIALS AND METHODS: Blood ADAM 8 was measured by ELISA. Cytokines/chemokines [interleukin-23 (IL-23), stromal cell-derived factor 1α/CXC chemokine ligand 12 (SDF-1α/CXCL12), interleukin-8 (IL-8), and soluble CD40 ligand (sCD40L)] were measured by chemiluminescent immunoassay. They were compared among five groups; normal/gastritis, high-risk, early GC (EGC), advanced GC (AGC) without distant metastasis, and AGC with distant metastasis by one-way analysis of variance in both training (n=80) and validation dataset (n=241). Clinicopathological features of GC and GC-associated cytokines were evaluated for their correlations with blood ADAM 8. To evaluate the diagnostic accuracy to predict GC, receiver operating characteristic (ROC) curve and logistic regression were used. RESULTS: Blood ADAM 8 significantly increased along GC carcinogenesis in both training (ANOVA, p<0.001) and validation dataset (p<0.001). It was significantly higher in EGC compared to high-risk (post-hoc Bonferroni, p=0.041) and normal (p<0.001). It was also higher in AGC compared with high-risk (p<0.001) and normal (p<0.001) groups. However, no significant difference was found between cancer groups. Blood ADAM 8 was correlated with N-stage (Spearman's correlation, γs=0.320, p=0.011), but not with T-stage or M-stage. Pearson's correlations showed blood ADAM 8 was closely correlated with pre-inflammatory cytokines, IL-23 (p=0.036) and SDF-1α/CXCL12 (p=0.037); however, it was not correlated with pro-angiogenic cytokine IL-8 (p=0.313), and sCD40L (p=0.702). ROC curve and logistic regression demonstrated that blood ADAM 8 showed higher diagnostic accuracy (sensitivity, 73.7%; specificity, 86.2%) than CEA (sensitivity, 23.1%; specificity, 91.4%). Combination of ADAM 8 and CEA further increased the diagnostic accuracy to predict GC (sensitivity, 81.8%; specificity, 84.0%). CONCLUSION: Blood ADAM 8 is a promising biomarker for early detection of GC.

Identificaiton of Novel Immunogenic Human Papillomavirus Type 16 E7-Specific Epitopes Restricted to HLA-A*33;03 for Cervical Cancer Immunotherapy

PURPOSE: To identify new immunogenic HLA-A*33;03-restricted epitopes from the human papillomavirus (HPV) 16 E7 protein for immunotherapy against cervical cancer. MATERIALS AND METHODS: We synthesized fourteen overlapping 15-amino acid peptides and measured intracellular interferon-γ (IFN-γ) production in PBMC and CD8+ cytotoxic T lymphocytes (CTLs) after sensitization with these peptides using flow cytometry and ELISpot assay. The immunogenicity of epitopes was verified using a ⁵¹Cr release assay with SNU1299 cells. RESULTS: Among the fourteen 15-amino acid peptides, E7₄₉₋₆₃ (RAHYNIVTFCCKCDS) demonstrated the highest IFN-γ production from peripheral blood mononuclear cells (PBMCs), and CD8+ CTLs sensitized with E7₄₉₋₆₃ showed higher cytotoxic effect against SNU1299 cells than did CD8+ CTLs sensitized with other peptides or a negative control group. Thirteen 9- or 10-amino acid overlapping peptides spanning E7₄₉₋₆₃, E7₅₀₋₅₉ (AHYNIVTFCC), and E7₅₂₋₆₁ (YNIVTFCCKC) induced significantly higher IFN-γ production and cytotoxic effects against SNU1299 cells than the other peptides and negative controls, and the cytotoxicity of E7₅₀₋₅₉- and E7₅₂₋₆₁-sensitized PBMCs was induced via the cytolytic effect of CD8+ CTLs. CONCLUSION: We identified E7₅₀₋₅₉ and E7₅₂₋₆₁ as novel HPV 16 E7 epitopes for HLA-A*33;03. CD8+ CTL sensitized with these peptides result in an antitumor effect against cervical cancer cells. These epitopes could be useful for immune monitoring and immunotherapy for cervical cancer and HPV 16-related diseases including anal cancer and oropharyngeal cancer.

Ascorbate Oxidase Minimizes Interference by High-Concentration Ascorbic Acid in Total Cholesterol Assays

No abstract available.

Evaluation of i-STAT CHEM8+ Point-of-Care Chemistry Analyzer

BACKGROUND: We evaluated the analytical performance of the Abbott i-STAT CHEM8+, a point-of-care testing system that measures 8 basic chemical analytes, namely, sodium, potassium, chloride, total carbon dioxide, BUN, creatinine, glucose, and ionized calcium. METHODS: The precision and linearity of 8 analytes were evaluated according to the CLSI guidelines EP15-A and EP6-A, respectively, using standard material provided by the manufacturer. i-STAT CHEM8+ and other primary methods (e.g. Hitachi Clinical Analyzer 7600 for 7 analytes, Nova CCX for ionized calcium) were also compared according to the CLSI guideline EP9-A2, using 113 patient samples. RESULTS: The standard deviation (SD) of within-run and total precision of 7 analytes except chloride was within the claimed SD or within the verification value. The coefficient of variation of total precision of 7 analytes except creatinine was within 2%. With regard to linearity, all 8 analytes showed first-order equation or at least no statistical difference with the first-order equation. We observed that the efficiency of i-STAT CHEM8+ was comparable to that of primary methods, and that this method has potential applications in the clinical laboratory. CONCLUSIONS: i-STAT CHEM8+ showed good precision and linearity, and an efficiency comparable to that shown by routine chemistry analyzers; thus, it has potential applications in the clinical laboratory. It can provide much faster results and relatively accurate value to clinicians in need of immediate results, such as in an emergency unit or in the intensive care unit.

Evaluation of i-STAT CHEM8+ Point-of-Care Chemistry Analyzer

BACKGROUND: We evaluated the analytical performance of the Abbott i-STAT CHEM8+, a point-of-care testing system that measures 8 basic chemical analytes, namely, sodium, potassium, chloride, total carbon dioxide, BUN, creatinine, glucose, and ionized calcium. METHODS: The precision and linearity of 8 analytes were evaluated according to the CLSI guidelines EP15-A and EP6-A, respectively, using standard material provided by the manufacturer. i-STAT CHEM8+ and other primary methods (e.g. Hitachi Clinical Analyzer 7600 for 7 analytes, Nova CCX for ionized calcium) were also compared according to the CLSI guideline EP9-A2, using 113 patient samples. RESULTS: The standard deviation (SD) of within-run and total precision of 7 analytes except chloride was within the claimed SD or within the verification value. The coefficient of variation of total precision of 7 analytes except creatinine was within 2%. With regard to linearity, all 8 analytes showed first-order equation or at least no statistical difference with the first-order equation. We observed that the efficiency of i-STAT CHEM8+ was comparable to that of primary methods, and that this method has potential applications in the clinical laboratory. CONCLUSIONS: i-STAT CHEM8+ showed good precision and linearity, and an efficiency comparable to that shown by routine chemistry analyzers; thus, it has potential applications in the clinical laboratory. It can provide much faster results and relatively accurate value to clinicians in need of immediate results, such as in an emergency unit or in the intensive care unit.

Annual Report on External Quality Assessment in Therapeutic Drug Monitoring and Drug of Abuse in Korea (2007) / 임상검사와정도관리

Two trials of external quality assessment for Therapeutic Drug Monitoring (TDM) subcommittee of Korean Association of Quality Assurance for Clinical Laboratory (KAQACL) were performed in 2007. Number of participating laboratories were increased to 109, by 5.63% increase comparing with the previous year. Response rates reached 98.7% for both trials slightly lower than that of the previous year. Two kinds of control materials were requested to be tested in each trial so that each institution could know the possible systematic error. In both trials, 20 test items were responded at least from one laboratory. The average drug item was 6.3 per institution, which was decreased slightly from 6.8 in recent 5 years. The most common test items were valproic acid, digoxin, carbamazepine, theophylline, phenytoin, and phenobarbital which were peformed in more than 55% of the participating laboratories, followed by cyclosporine, vancomycin, lithium, tacrolimus, methotrexate, amikacin, gentamicin, salicylate, tobramycin, acetaminophen, primidone, free phenytoin, and amitryptyline. The inter-laboratory coefficients of variations showed simliar tendency comparing with those of the previous years. We started the proficiency test for drug of abuse from 2007 and got the response from 13 and 17 laboratories in the 1st and 2nd trial, respectively. Average drug items were 3.4 for the 2nd trial. We found the relatively good performances as we got the correct answers from all laboratories except 4 for each one mistake. In conclusion, the TDM external quality assessment of 2007 showed grossly similar pattern comparing with those of previous year and drug of abuse proficiency testing showed a relatively good performance.

Annual Report on External Quality Assessment in Therapeutic Drug Monitoring and Drug of Abuse in Korea (2007) / 임상검사와정도관리

Two trials of external quality assessment for Therapeutic Drug Monitoring (TDM) subcommittee of Korean Association of Quality Assurance for Clinical Laboratory (KAQACL) were performed in 2007. Number of participating laboratories were increased to 109, by 5.63% increase comparing with the previous year. Response rates reached 98.7% for both trials slightly lower than that of the previous year. Two kinds of control materials were requested to be tested in each trial so that each institution could know the possible systematic error. In both trials, 20 test items were responded at least from one laboratory. The average drug item was 6.3 per institution, which was decreased slightly from 6.8 in recent 5 years. The most common test items were valproic acid, digoxin, carbamazepine, theophylline, phenytoin, and phenobarbital which were peformed in more than 55% of the participating laboratories, followed by cyclosporine, vancomycin, lithium, tacrolimus, methotrexate, amikacin, gentamicin, salicylate, tobramycin, acetaminophen, primidone, free phenytoin, and amitryptyline. The inter-laboratory coefficients of variations showed simliar tendency comparing with those of the previous years. We started the proficiency test for drug of abuse from 2007 and got the response from 13 and 17 laboratories in the 1st and 2nd trial, respectively. Average drug items were 3.4 for the 2nd trial. We found the relatively good performances as we got the correct answers from all laboratories except 4 for each one mistake. In conclusion, the TDM external quality assessment of 2007 showed grossly similar pattern comparing with those of previous year and drug of abuse proficiency testing showed a relatively good performance.

The Clinical Usefulness of Cystatin C in Evaluating Renal Function in Children with Various Renal Diseases

PURPOSE: GFR(glomerular filtration rate) is a fundamental parameter in detecting renal impairment and predicts the progression of renal disease. Because serum creatinine has several disadvantages, serum cystatin C has been recently proposed as a new endogenous marker for GFR. We compared serum cystatin C with creatinine and creatinine clearance to investigate the clinical usefulness of cystatin C. METHODS: We retrospectively analyzed 46 patients(60 case numbers) who had various renal diseases and classified them into 3 groups according to creatinine clearance(Group 1 : CrCl 60 mL/min/1.73 m2). We measured serum creatinine, cystatin C and creatinine clearance and also analyzed the correlations among them. RESULTS: Serum cystatin C and creatinine showed a similar correlation to creatinine clearance (r=0.685, r=0.640, respectively) and showed similar diagnostic accuracy in detecting decreased GFR(AUC, cystatin C 0.829 vs. creatinine 0.826, P=0.848). Serum cystatin C showed a greater sensitivity for detecting a decreased GFR than creatinine in Group 2 and 3(Group 1 : 100% vs. 100%, Group 2 : 70% vs. 35%, Group 3 : 46% vs. 15%). CONCLUSIONS: Serum cystatin C could be a useful endogenous marker for GFR and would be superior to serum creatinine in early detection of renal impairment in pediatric patients with renal diseases.

Effects of Short-Term Partial Correction of Anemia in End-Stage Renal Disease (ESRD) Patients on Maintenance Hemodialysis : Changes of Amino-Terminal Pro B-type Natriuretic Peptide (NT-pro BNP) and Echocardiographic Parameters / 대한신장학회잡지

BACKGROUND: Anemia is known to be one of the important risk factors in the development and the aggravation of cardiovascular diseases. This study was undertaken to evaluate the effect of anemia correction on blood NT-pro BNP level and echocardiographic parameters in ESRD patients on hemodialysis. METHODS: Recombinant human erythropoietin (rHuEPO) was administered in 20 hemodialysis patients (median age 51.5, M:F=2.3:1) with a target hemoglobin>12.0 g/dL for 3 months. All patients were subjected to a serial follow-up of hemoglobin, hematocrit, and NT-pro BNP. Echocardiographic examination was also performed before and after 3 months of therapy. RESULTS: Hemoglobin was increased at 3 months [12.3 g/dL (11.8-13.6)] compared with baseline [9.8 g/dL (9.1-10.4)] (p<0.01), and NT-pro BNP was significantly decreased at 3 months [3415 pg/mL (2717- 8160)] compared with baseline [6371 pg/mL (2338- 18269)] (p<0.05). Echocardiographic examination revealed no significant changes in left ventricular ejection fraction and left ventricular mass index. In Doppler imaging, however, there was significant decrease in E velocity [62.5 cm/sec (52.8-83.5) vs. 57.0 cm/sec (45.0-60.0), p<0.05], thereby decrement in E/E' [15.6 (13.4-25.7) vs. 14.3 (11.5-22.2), p<0.05]. CONCLUSION: Partial correction of anemia with rHuEPO in ESRD patients on hemodialysis results in the reduction of blood NT-pro BNP level and the decrease of E velocity and E/E'.

Effects of Short-Term Partial Correction of Anemia in End-Stage Renal Disease (ESRD) Patients on Maintenance Hemodialysis : Changes of Amino-Terminal Pro B-type Natriuretic Peptide (NT-pro BNP) and Echocardiographic Parameters / 대한신장학회잡지

BACKGROUND: Anemia is known to be one of the important risk factors in the development and the aggravation of cardiovascular diseases. This study was undertaken to evaluate the effect of anemia correction on blood NT-pro BNP level and echocardiographic parameters in ESRD patients on hemodialysis. METHODS: Recombinant human erythropoietin (rHuEPO) was administered in 20 hemodialysis patients (median age 51.5, M:F=2.3:1) with a target hemoglobin>12.0 g/dL for 3 months. All patients were subjected to a serial follow-up of hemoglobin, hematocrit, and NT-pro BNP. Echocardiographic examination was also performed before and after 3 months of therapy. RESULTS: Hemoglobin was increased at 3 months [12.3 g/dL (11.8-13.6)] compared with baseline [9.8 g/dL (9.1-10.4)] (p<0.01), and NT-pro BNP was significantly decreased at 3 months [3415 pg/mL (2717- 8160)] compared with baseline [6371 pg/mL (2338- 18269)] (p<0.05). Echocardiographic examination revealed no significant changes in left ventricular ejection fraction and left ventricular mass index. In Doppler imaging, however, there was significant decrease in E velocity [62.5 cm/sec (52.8-83.5) vs. 57.0 cm/sec (45.0-60.0), p<0.05], thereby decrement in E/E' [15.6 (13.4-25.7) vs. 14.3 (11.5-22.2), p<0.05]. CONCLUSION: Partial correction of anemia with rHuEPO in ESRD patients on hemodialysis results in the reduction of blood NT-pro BNP level and the decrease of E velocity and E/E'.

Annual Report on External Quality Assessment in Therapeutic Drug Monitoring in Korea (2005) / 임상검사와정도관리

Two trials of external quality assessment for Therapeutic Drug Monitoring (TDM) subcommittee of Korean Association of Quality Assurance for Clinical Pathology (KAQACP) were performed in 2005. The number of participating laboratories were increased to 95, by 6.7% comparing with the previous year. Response rates were 100.0% for both trials just like the two previous years. Two kinds of control materials were requested to be tested in each trial so that each institution could know the possible systematic error. In both trials, 20 test items were responded at least from one laboratory. The average drug item was 6.7 per institution, which was elevated slightly from 6.5 in recent 5 years. The most common test items were digoxin, valproic acid, carbamazepine, theophylline, phenytoin, and phenobarbital which were peformed in more than 65% of participating laboratories, followed by cyclosporine, lithium, vancomycin, tacrolimus, methotrexate, amikacin, gentamycin, tobramycin, salicylate, primidone, acetaminophen, free phenytoin, amitryptyline, and ethosuximide. The most widely used TDM analyzer was Abbott TDx/TDxFLx (41.7%), followed by Abbott AxSym (23.3%), and Roche Cobas Integra (19.2%). The inter-laboratory coefficients of variations were not much improved comparing with previous years. We also determined cyclosporine with reference method using liquid chromatography-tandem mass spectrometry. In conclusion, the TDM external quality assessment of 2005 showed grossly similar pattern comparing with those of previous year with increasing participating laboratories.

Effectiveness of Real-Time Quantitative PCR Compare to Repeat PCR for the Diagnosis of Charcot-Marie-Tooth Type 1A and Hereditary Neuropathy with Liability to Pressure Palsies

The majority of cases of Charcot-Marie-Tooth type 1A (CMT1A) and of hereditary neuropathy with a liability to pressure palsies (HNPP) are the result of heterozygosity for the duplication or deletion of peripheral myelin protein 22 gene (PMP22) on 17p11.2. Southern blots, pulsed-field gel electrophoresis (PFGE), fluorescence in situ hybridization (FISH) and polymorphic marker analysis are currently used diagnostic methods. But they are time-consuming, labor-intensive and have some significant limitations. We describe a rapid real- time quantitative PCR method for determining gene copy number for the identification of DNA duplication or deletion occurring in CMT1A or HNPP and compare the results obtained with REP-PCR. Six patients with CMT1A and 14 patients with HNPP [confirmed by Repeat (REP) -PCR], and 16 patients with suspicious CMT1A and 13 patients with suspicious HNPP [negative REP-PCR], and 15 normal controls were studied. We performed REP-PCR, which amplified a 3.6 Kb region (including a 1.7Kb recombination hotspot), using specific CMT1A-REP and real-time quantitative PCR on the LightCycler system. Using a comparative threshold cycle (Ct) method and beta-globin as a reference gene, the gene copy number of the PMP22 gene was quantified. The PMP22 duplication ratio ranged from 1.35 to 1.74, and the PMP22 deletion ratio from 0.41 to 0.53. The PMP22 ratio in normal controls ranged from 0.81 to 1.12. All 6 patients with CMT1A and 14 patients with HNPP confirmed by REP-PCR were positive by real-time quantitative PCR. Among the 16 suspicious CMT1A and 13 suspicious HNPP with negative REP-PCR, 2 and 4 samples, respectively, were positive by real-time quantitative PCR. Real-time quantitative PCR is a more sensitive and more accurate method than REP-PCR for the detection of PMP22 duplications or deletions, and it is also faster and easier than currently available methods. Therefore, we believe that the real-time quantitative method is useful for diagnosing CMT1A and HNPP.

Annual Report on External Quality Assessment in Therapeutic Drug Monitoring in Korea (2004) / 임상검사와정도관리

Two trials of external quality assessment for Therapeutic Drug Monitoring (TDM) Subcommittee of Korean Association of Quality Assurance for Clinical Pathology (KAQACP) were performed in 2004. Number of participating laboratories were increased to 89, by 11.3% increase comparing with the previous year. Response rates were 100.0% for both trials just like the previous year. Two kinds of control materials were requested to be tested in each trial so that each institution could know the possible systematic error. In both trials, 20 test items were responded at least from one laboratory. The average drug item was 6.8 per institution, which was elevated slightly from 6.5 in recent 5 years. The most common test items were valproic acid, digoxin, phenytoin, carbamazepine, theophylline, and phenobarbital which were peformed in more than 71% of participating laboratories, followed by cyclosporine, lithium, tacrolimus, vancomycin, methotrexate, amikacin, gentamycin, salicylate, tobramycin, acetaminophen, primidone, free phenytoin, and amitryptyline. The most widely used TDM analyzer was Abbott TDx/TDxFLx (41.6%), followed by Roche Cobas Integra (21.3%), and Abbott AxSym (20.2%). The inter-laboratory coefficients of variations were not greatly improved comparing with previous years. We also determined cyclosporine and tacrolimus with reference method using liquid chromatography-tandem mass spectrometry. In conclusion, the TDM external quality assessment of 2004 showed grossly similar pattern comparing with those of previous year, except the 11.3% increase of participating laboratories.

Evaluation of Clinical Usefulness of PREG-Q(TM) as a Screening Test for Pregnancy / 임상검사와정도관리

BACKGROUND: Among the many methods estimating the quantity of beta-hCG for pregnancy testing in urine, immunochromatography is one of most widely used semi-quantitative detection method for its convenience to use and also for its rapid result reporting system. PREG-Q(TM) is a newly introduced semi-quantitative immunochromatography method for detecting b-hCG. Clinical usefulness of PREG-Q(TM) was evaluated as a screening test for early pregnancy detection. METHODS: Accuracy, detection limit, cross-reactivity with various glycoprotein hormones, interference study, and comparison study using total 100 urine samples from pregnant (50 samples) and non-pregnant women (50 samples) was evaluated. RESULTS: All the 50 urine samples of pregnant women showed positive results, and another 50 urine samples of non-pregnant women showed negative results with PREG-Q(TM). The lower detection limit of PREG-Q(TM) was 25 mIU/mL and the result was not affected by addition of glycoprotein hormones tested. Interfering substance causing false negative or false positive results enrolled didn't affect the test results in this study. CONCLUSIONS: We conclude PREG-Q(TM) is an excellent test kit for pregnancy test, and is valuable especially for detecting early pregnancy.

Annual Report on External Quality Assessment in Therapeutic Drug Monitoring in Korea (2003) / 임상검사와정도관리

Two trials of external quality assessment for Therapeutic Drug Monitoring (TDM) subcommittee of Korean Association of Quality Assurance for Clinical Pathology (KAQACP) were performed in 2003. Number of participating laboratories were 80 which is similar to those of the previous year. Response rates were elevated to 100.0% for both trials. Two kinds of control materials were requested to be tested in each trial so that each institution could know the possible systematic error. In both trials, 20 test items were responded at least from one laboratory. The average drug item was 7.0 per institution, which was elevated slightly from 6.5 in recent 5 years. The most common test items were valproic acid, digoxin, phenytoin, carbamazepine, theophylline, and phenobarbital, which were peformed in more than 75% of participating laboratories, followed by cyclosporine, lithium, methotrexate, tacrolimus, vancomycin, amikacin, gentamycin, salicylate, tobramycin, acetaminophen, primidone, free phenytoin, and amitryptyline. The most widely used TDM analyzer was Abbott TDx/TDxFLx (52%), but its proportion were decreased slightly comparing with the previous years. The interlaboratory coefficients of variations were not greatly improved comparing with previous years. In conclusion, the TDM external quality assessment of 2003 showed grossly similar pattern comparing with those of previous year, except that the response rate was elevated to 100% and two levels of control material were used in each trials.

Adoptive Immunotherapy for Cytomegalovirus (CMV) Disease in Immunocompromised Patients

Cytomegalovirus (CMV) reactivation in immune compromised patients such as those undergoing hematopoietic progenitor cell transplantation (HPCT) and those with HIV infections can cause severe morbidity and mortality despite treatment with appropriate antiviral agents. The recovery of Cytomegalovirus (CMV) specific cytotoxic T lymphocytes (CTL) plays an important role in the reconstitution of CMV specific immunity in immunocompromised patients. Recent studies have reported that CMV reactivation can be successfully treated by adoptive transfer of CMV-specific T cell clones from CMV seropositive donors expanded in vitro with CMV infected fibroblasts or lysates of CMV infected cells. Other studies have used immune dominant CMV proteins or peptides to expand CMV-specific cytotoxic T lymphocytes. This review describes the clinical manifestations of CMV disease in immunocompromised patients, recent advances of antiviral therapy for CMV disease, the principals of the induction of cellular immune response to CMV, and the clinical application of CMV immunotherapy.

Comparison of Acid-Fast staining, PCR, LCR, PCR=Hybridization for dection of mycobacterum tuberculosis in clinical specimens / 결핵

BACKGROUND: Mycobacterial culture is a confirmatory test to detect M.tuberculosis, but it takes at least 6 weeks to diagnose. PCR is a rapid and sensitive method, but it is known that PCR has a high false positive rate due to contamination, and a high false negative rate due to inhibitors. It is also known that LCR and PCR-Hybridization, recently developed methods, are more specific methods than PCR in terms of detection M.tuberculosis. In this study, we estimated the clinical utility of in house PCR, LCR and PCR-Hybridization for the detection of M.tuberculosis. METHODS: We evaluated 75 specimens, upon which M.tuberculosis culture based testing was requested, by PCR LCR, and PCR-Hybridization and compared results. Mycobacterial culture was performed on 3% Ogawa media for 8 weeks, and an in house PCR, LCx Mycobacterium tuberculosis assay kit(Abbott Laboratories, North Chicago, III) and the AMPLICOR M.tuberculosis test kit(Roche Molecular Systems, Inc. Branchburg, NJ, USA). RESULTS: In the view of the culture results, the sensitivities of the three tests were 40%, 80%, and 100% and their specificities were 98.6%, 94.3%, and 94.3%. CONCLUSION: LCR and PCR-Hybridization and rapid and sensitive methods for detecting M.tuberculosis in clinical laboratories.

Emerging antimicrobial resistance, plasmid profile and pulsed-field gel electrophoresis pattern of the endonuclease-digested genomic DNA of Neisseria gonorrhoeae

Resistant gonococci are very prevalent in many countries, particularly in Asia. This study was conducted to determine the trend of resistance, the effect of decreasing the ciprofloxacin susceptibilities of gonococci on the prevalence of penicillinase-producing N. gonorrhoeae (PPNG), and to compare the epidemiology of strains with the previous studies. A total of 602 strains of gonococci were isolated from prostitutes in 1997-1999. Antimicrobial susceptibility was tested by NCCLS disk diffusion and agar dilution methods. For epidemiologic analysis, vplasmid analysis and pulsed-field gel electrophoresis (PFGE) were performed. The proportion of PPNG remained high (79%), and the strains with decreased susceptibility to ciprofloxacin increased significantly from 67% in 1997 to 84% in 1999. Compared to our previous study, the PFGE patterns were similar, while the proportion of strain with the 3.2-MDa plasmid markedly decreased. In conclusion, a rapid increase in ciprofloxacin-nonsusceptible strains may suggest difficulties in the treatment of gonococcal infections in the near future with the drug. The recent decrease of PPNG with the 3.2-MDa plasmid may suggest that there is an epidemiological change in gonococcal infections, and the prevalence of related PFGE patterns suggests the dissemination of a few clones among the high risk populations.