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Experience of a Break-Even Point Analysis for Make-or-Buy Decision.

The Korean Journal of Laboratory Medicine.2006;26(6):460-464. doi:10.3343/kjlm.2006.26.6.460

BACKGROUND: Cost containment through continuous quality improvement of medical service is required in an age of a keen competition of the medical market. Laboratory managers should examine the matters on make-or-buy decision periodically. On this occasion, a break-even point analysis can be useful as an analyzing tool. In this study, cost accounting and break-even point (BEP) analysis were performed in case that the immunoassay items showing a recent increase in order volume were to be in-house made. METHODS: Fixed and variable costs were calculated in case that alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), prostate-specific antigen (PSA), ferritin, free thyroxine (fT4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), CA 125, CA 19-9, and hepatitis B envelope antibody (HBeAb) were to be tested with Abbott AxSYM instrument. Break-even volume was calculated as fixed cost per year divided by purchasing cost per test minus variable cost per test and BEP ratio as total purchasing costs at break-even volume divided by total purchasing costs at actual annual volume. RESULTS: The average fixed cost per year of AFP, CEA, PSA, ferritin, fT4, T3, TSH, CA 125, CA 19- 9, and HBeAb was won 8,279,187 and average variable cost per test, won 3,786. Average break-even volume was 1,599 and average BEP ratio was 852%. Average BEP ratio without including quality costs such as calibration and quality control was 74%. CONCLUSIONS: Because the quality assurance of clinical tests cannot be waived, outsourcing all of 10 items was more adequate than in-house make at the present volume in financial aspect. BEP analysis was useful as a financial tool for make-or-buy decision, the common matter which laboratory managers meet with.
alpha-Fetoproteins ; Calibration ; Carcinoembryonic Antigen ; Cost Control ; Ferritins ; Hepatitis B ; Immunoassay ; Outsourced Services ; Prostate-Specific Antigen ; Quality Control ; Quality Improvement ; Thyrotropin ; Thyroxine ; Triiodothyronine

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The Relationship between High Sensitivity C-Reactive Protein and Metabolic Syndrome according to the Fasting Glucose Level at Medical Checkups.

Eun Hee NAH ; Jin Kyoung LEE

The Korean Journal of Laboratory Medicine.2006;26(6):454-459. doi:10.3343/kjlm.2006.26.6.454

BACKGROUND: This study was performed to investigate the difference in high sensitivity C-reactive protein (hsCRP) and metabolic syndrome according to the fasting glucose level, especially between the groups of less than 100 mg/dL and 100-109 mg/dL, which were conventionally categorized into normal levels. METHODS: Those who underwent routine medical checkups aged above 20 (male, 3,221; female, 3,334) at a Health Promotion Center (Seoul, Korea) were divided into normal fasting glucose group I (glucose <100 mg/dL), normal fasting glucose group II (glucose, 100-109 mg/dL), impaired fasting glucose group, and diabetes mellitus group. The hsCRP, obesity index, blood pressure, total cholesterol, triglyceride, high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and lipoprotein(a) [Lp(a)] were compared among the groups. The hsCRP and the components of metabolic syndrome were compared. RESULTS: The hsCRP level, age, obesity index, blood pressure, total cholesterol and triglyceride significantly increased along with the increment in fasting glucose level in the 4 groups. The hsCRP had a positive correlation with the fasting glucose level, age, and systolic blood pressure, while it had a negative correlation with HDL-C. The metabolic syndrome was more common in the group with a higher level of glucose. CONCLUSIONS: The group with glucose level of less than 110 mg/dL, conventionally categorized into normal range, needs to be subdivided into a group of 100-109 mg/dL and a group of less than 100 mg/dL. The former group seems to require more efforts to have the glucose level to be maintained under the level of 100 mg/dL.
Blood Pressure ; C-Reactive Protein* ; Cholesterol ; Diabetes Mellitus ; Fasting* ; Female ; Glucose* ; Health Promotion ; Humans ; Lipoprotein(a) ; Obesity ; Reference Values ; Triglycerides

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A Korean Family with Wilson Disease Occurred in Two Consecutive Generations.

Ji Seon CHOI ; Joon Hyeok LEE ; Chang Seok KI

The Korean Journal of Laboratory Medicine.2006;26(6):449-453. doi:10.3343/kjlm.2006.26.6.449

Wilson disease (WD) is one of the most common inborn errors of metabolism characterized by degenerative changes in the brain, liver and kidney dysfunction, and Kayser-Fleischer rings due to toxic accumulation of copper. We investigated a Korean family with WD occurred in two consecutive generations. The proband, a 14-yr-old girl, was noticed to have abnormal liver function on a routine health examination at school and was diagnosed of having WD by further laboratory tests and liver biopsy. Molecular genetic analysis of ATP7B gene demonstrated that she was homozygous for Ala-874Val mutation, one of the three common mutations in Korean patients with WD. Further study for her family members revealed that the proband's father, a paternal uncle, and the youngest sister were compound heterozygous for Ala874Val and Asn1270Ser mutations of the ATP7B gene. In addition, the proband's mother and a younger sister were heterozygous carriers of Ala874Val mutation. Therefore, WD occurred in two consecutive generations due to a WD father and a heterozygous mother. Actually, abnormal results on liver function tests were found in the proband's father and a paternal uncle a few years ago but a diagnosis of WD has not been made. Therefore, although WD has been thought to be uncommon in Korea, it should be considered in a differential diagnosis of patients exhibiting abnormal liver function with unknown cause.
Biopsy ; Brain ; Copper ; Diagnosis ; Diagnosis, Differential ; Family Characteristics* ; Fathers ; Female ; Hepatolenticular Degeneration* ; Humans ; Kidney ; Korea ; Liver ; Liver Function Tests ; Metabolism, Inborn Errors ; Molecular Biology ; Mothers ; Siblings

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Performance Evaluation of Real-Q HBV Quantification Kit for HBV DNA by Real-Time PCR.

Sang Hyun HWANG ; Choong Hwan CHA ; Yoo Li KIM ; Oh Joong KWON ; Heung Bum OH

The Korean Journal of Laboratory Medicine.2006;26(6):442-448. doi:10.3343/kjlm.2006.26.6.442

BACKGROUND: Hepatitis B virus (HBV) DNA quantification is important for the management of HBV infection and identification of the development of resistance. The susceptibility to contamination and more variable reproducibility of results with the conventional HBV DNA quantification method have raised the need of a more simple and accurate method for HBV DNA quantification. Real-time quantitative PCR assays recently introduced in the laboratory can meet these needs. In this study, we evaluated the performance of the Real-Q HBV Quantification kit developed in Korea. METHODS: We evaluated the recovery of DNA extraction, the interference of internal control, an analytical sensitivity, specificity, and reproducibility, a clinical specificity, and a reportable range of the Real-Q HBV Quantification kit. The quantification result was also compared to that obtained by the Digene Hybrid-Capture II. RESULTS: The mean percent recovery was 108.6% and there was no interference with the internal control on DNA extraction. None of HIV, hepatitis C virus, or cytomegalovirus showed a cross-reactivity with HBV. This assay detected HBV DNA in a linear range from 10(2) to 10(10) copies/mL, with the detection limit of 56 copies/mL. The assay exhibited a low within-run CV (coefficient of variation) (8.7-11.9%), between-run CV (10.5-14.7%), and between-day CV (13.2-21.4%). No HBV DNA was detected in any of 100 samples without HBV, resulting in a clinical specificity of 100%. The levels of HBV DNA showed a good correlation with those determined with Digene Hybrid-Capture II (R2=0.9827). CONCLUSIONS: The Real-Q HBV Quantification kit showed a good analytical sensitivity, specificity, and high reliability with a broad reportable range. This assay should be clinically useful in managing patients with HBV infection.
Cytomegalovirus ; DNA* ; Hepacivirus ; Hepatitis B virus ; HIV ; Humans ; Korea ; Limit of Detection ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction* ; Reproducibility of Results ; Sensitivity and Specificity

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Evaluation of HBs Ag, HCV and HIV Ag-Ab Assays using Bio-Rad Elite Microplate Analyzer.

Sang Hyun HWANG ; Heung Bum OH ; Hyon Suk KIM ; Eun Yup LEE

The Korean Journal of Laboratory Medicine.2006;26(6):436-441. doi:10.3343/kjlm.2006.26.6.436

BACKGROUND: In this study, we evaluated the performance of Elite microplate analyzer (Bio-Rad Laboratories, France) and the related assays (ULTRA line) for the detection of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). METHODS: Seroconversion panels, HBsAg positive/HBsAg negative (n=99/n=1,422), anti-HCV positive/negative (n=97/n=1,670), and anti-HIV positive/negative (n=112/n=1,704) samples were used to evaluate the performance of Monolisa HBsAg ULTRA, Monolisa HCV Ag-Ab ULTRA, and Genscreen ULTRA HIV Ag-Ab, respectively. The agreement of Elite microplate analyzer with CODA analyzer (Bio-Rad Laboratories, CA, USA) was also evaluated. RESULTS: The detection limit of Monolisa HBsAg ULTRA was 0.034 IU/mL. For Monolisa HBsAg ULTRA, Monolisa HCV Ag-Ab ULTRA, and Genscreen ULTRA HIV Ag-Ab, diagnostic sensitivities were all 100%, diagnostic specificities were 100%, 99.8% and 99.9%, and total CVs (coefficients of variation) were 13.8-17.5%, 3.4-5.2%, and 7.5-9.5%, respectively. The agreement of Elite microplate analyzer with CODA analyzer was 99.5%. CONCLUSIONS: The performance of Elite microplate analyzer and the related assays on analytical sensitivity, precision, early detection, diagnostic sensitivity and specificity was all adequate for a mass screening. However, further large multi-center studies should be performed to validate our results.
Hepacivirus ; Hepatitis B Surface Antigens ; Hepatitis B virus ; HIV* ; Limit of Detection ; Mass Screening ; Sensitivity and Specificity

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Comparison of Three Assay Systems for Qualitative and Quantitative Results of Hepatitis B Surface Antibody.

Soo Jin YOO ; Hye Jeon OH ; Bo Moon SHIN

The Korean Journal of Laboratory Medicine.2006;26(6):431-435. doi:10.3343/kjlm.2006.26.6.431

BACKGROUND: With a technical improvement of the assay system, automated immunoassay analyzers for hepatitis B surface antibody (anti-HBs) are widely used. However, some discrepancies between assays are still being reported. We compared the qualitative and quantitative results of three kinds of anti-HBs assays. METHODS: Serum samples were collected from 517 patients and anti-HBs were determined using AxSYM AUSAB, Bayer ADVIA Centaur, and Roche Elecsys assay systems. RESULTS: The concordance rates between the three assays were 95.1% (543/571). The concordance rates were 97.7% between Centaur and Elecsys, 96.3% between AxSYM and Centaur, and 95.6% between AxSYM and Elecsys. Their correlation coefficients for quantitative results were 0.97, 0.94, and 0.93 in the same order. Twenty-eight specimens showed discrepant results, and all of them had antibody values below 31.5 mIU/mL. CONCLUSIONS: Three immunoassays for anti-HBs presented a high concordance and correlation; however, the results should be interpreted with caution, because there were still significant differences between assay methods, especially for a low-level of anti-HBs.
Hepatitis B virus ; Hepatitis B* ; Hepatitis* ; Humans ; Immunoassay

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HBV DNA Quantitation Using Real-time PCR.

Jeong HEO ; Won Ook GO ; Gwang Ha KIM ; Dae Hwan KANG ; Geun Am SONG ; Mong CHO ; Hyung Hoi KIM ; Eeu Yup LEE

The Korean Journal of Laboratory Medicine.2006;26(6):424-430. doi:10.3343/kjlm.2006.26.6.424

BACKGROUND: Accurate measurement of the concentration of hepatitis B virus (HBV) DNA in clinical samples is important for the appropriate treatment of patients and evaluation of their therapeutic responses. In addition, the concentration of HBV DNA in the serum of patients with chronic HBV infection has a very broad range. Real-time PCR is very sensitive and useful to detect HBV DNA in a wide range of concentrations. We designed new primers and probes for real-time PCR to detect HBV DNA. METHODS: Primers and probes specific for HBV were designed. EUROHEP HBV DNA standards (NIBSC, Hertfordshire, UK) with the HBV DNA concentration of 7.0 x 10(4) copies/mL was used to determine the calibration curve and efficacy for the real-time PCR assay. Sensitivity, dynamic range, and precision were evaluated. The correlation between the real-time PCR and Cobas Amplicor HBV Monitor(TM) assay in the measurement of serum HBV DNA concentrations in 52 patients with chronic HBV infection was evaluated. RESULTS: The sensitivity of the assay was approximately 6.08 x 10(2) copies/mL for HBV, and the quantitation was accurate and reproducible over a wide dynamic range from 6.1 x 0(2) to 6.5 x 10(9) copies/mL without any dilution of specimens. The assay showed low coefficients of variation of repeatability (3.7-24.9%) and reproducibility (7.8-24.7%). The results were found to correlate well with those obtained by Cobas Amplicor HBV Monitor(TM) kit. CONCLUSIONS: We provide a new in-house method for the measurement of serum HBV DNA using real-time PCR, which enables us to detect HBV DNA rapidly, sensitively, and accurately.
Calibration ; DNA* ; Hepatitis B virus ; Humans ; Real-Time Polymerase Chain Reaction*

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Usefulness of Anti-HCV ELISA Test and HCV Reverse Transcriptase-PCR for the Diagnosis of Hepatits C Viral Infection.

Myeong Hee KIM ; Hee Joo LEE ; Su Yon PARK ; Youn Sik LEE ; Jin Tae SUH

The Korean Journal of Laboratory Medicine.2006;26(6):418-423. doi:10.3343/kjlm.2006.26.6.418

BACKGROUND: The diagnosis of hepatitis C virus (HCV) infection is screened by anti-HCV enzymelinked immunosorbant assay (ELISA) and confirmed by recombinant immunoblotting assay (RIBA) or HCV RT-PCR. We attempted to evaluate the results between anti-HCV ELISA and a qualitative HCV RT-PCR. METHODS: Four hundred and twenty patients who were tested with anti-HCV ELISA and HCV RTPCR, simultaneously, from January 2002 to June 2005 were enrolled in this study. Anti-HCV ELISA was performed by AxSYM HCV version 3.0 (Abbott Laboratories, USA). HCV RT-PCR was performed using in-house RT-nested PCR methods from January 2002 to October 2004 and HCV Genotype Amplification Kit (LiPA) (Bayer Healthcare, USA) from November 2004 to June 2005. RESULTS: Of the 420 patients tested, 321 were positive for anti-HCV ELISA, and 204 were positive for RT-PCR. The positive predictability of anti-HCV ELISA was 63.6%. Among anti-HCV positive patients, RT-PCR was positive in 7.3% of the patients with sample/cut-off (S/CO)<6, compared with 82.8% of the patients with S/CO> or =6. Among the 117 patients with positive anti-HCV, but with negative HCV RT-PCR, 64 had liver diseases such as chronic hepatitis C, chronic hepatitis B, or hepatocellular carcinoma. Twelve patients showed positive HCV RT-PCR, but negative anti-HCV results; of these 9 had hepatic dysfunction. CONCLUSIONS: In the patients who were positive for anti-HCV ELISA with a low S/CO, HCV RT-PCR positivity was shown in a low proportion. Therefore, in such cases, the results should be confirmed by RIBA or HCV RT-PCR. The liver function test showed increased levels of hepatic enzymes in patients with positive HCV RT-PCR, but negative anti-HCV. Such findings correlate to an early phase of chronic hepatitis C, suggesting the necessity of continuous follow up.
Carcinoma, Hepatocellular ; Delivery of Health Care ; Diagnosis* ; Enzyme-Linked Immunosorbent Assay* ; Follow-Up Studies ; Genotype ; Hepacivirus ; Hepatitis B, Chronic ; Hepatitis C ; Hepatitis C, Chronic ; Humans ; Immunoblotting ; Liver Diseases ; Liver Function Tests ; Polymerase Chain Reaction

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Mechanism of VanB Phenotype in Vancomycin-Resistant Enterococci carrying vanA gene.

Il Joong PARK ; Wee Gyo LEE ; Hyukmin LEE ; Dongeun YONG ; Kyungwon LEE ; Eui Chong KIM ; Seok Hoon JEONG ; Yeon Jun PARK ; Tae Yeal CHOI ; Young UH ; Jong Hee SHIN ; Jongwook LEE ; Ji young AHN ; Sung Hee LEE ; Gun Jo WOO

The Korean Journal of Laboratory Medicine.2006;26(6):412-417. doi:10.3343/kjlm.2006.26.6.412

BACKGROUND: Recently, vancomycin-resistant enterococci (VRE) with the vanA genotype that are susceptible to teicoplanin have been described in Japan, Taiwan, and Korea. The investigators suggested three point mutations in the putative sensor domain of vanS or impairment of accessory proteins VanY and VanZ as an explanation for the VanB phenotype-vanA genotype VRE. In this study, we analyzed Tn1546-like elements to determine the molecular mechanisms responsible for the impaired glycopeptide resistance of clinical VRE isolates with VanB phenotype-vanA genotype from Korea. METHODS: From 2001 to 2004, 28 clinical isolates of Enterococcus faecium with VanB phenotypevanA genotype were collected from 8 different university hospitals in diverse geographic areas in Korea. For structural analysis of Tn1546-like elements, PCR amplifications for internal regions of Tn1546 were performed. The purified PCR products were directly sequenced with an ABI Prism 3100 DNA sequencer. RESULTS: The sequence data of the vanS regulatory gene revealed that none of the isolates had any point mutations in this gene. All 28 isolates had a complete or incomplete deletion of vanY gene. Of these, 13 strains represented a complete deletion of vanZ, and 2 strains showed the deletion of nucleotides near the end point of vanX. CONCLUSIONS: The mechanism of VanB phenotype-vanA genotype in VRE isolates from Korea is not point mutations of vanS but the rearrangements of vanX, vanY and vanZ.
DNA ; Enterococcus faecium ; Genes, Regulator ; Genotype ; Hospitals, University ; Humans ; Japan ; Korea ; Nucleotides ; Phenotype* ; Point Mutation ; Polymerase Chain Reaction ; Research Personnel ; Taiwan ; Teicoplanin

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Comparison of Two Enzyme Immunoassays for Clostridium difficile Toxin A.

Soo Jin YOO ; Jung Oak KANG ; Hye Jun OH ; Bo Moon SHIN

The Korean Journal of Laboratory Medicine.2006;26(6):408-411. doi:10.3343/kjlm.2006.26.6.408

BACKGROUND: Clostridium difficile is one of the most important pathogens responsible for nosocomial diarrhea. The disease is mediated by two toxins, designated as A and B; therefore, identification of the toxins is important for diagnosis. However, culture or cytotoxin assay are not easily done because of tedious procedures. Instead, toxin A immunoassay is widely used. We evaluated two different enzyme immunoassays (EIA) for C. difficile toxin A and compared them with culture and PCR results. METHODS: A total of 65 stool specimens were examined for toxin A using enzyme linked fluorescent immunoassay (ELFA, VIDAS CD II, Bio-Merieux, France) and enzyme linked immunosolvent assay (ELISA, C.DIFFICILE TOX A II, TECHLAB, USA ) and were also cultured for C. difficile using cycloserine cefoxitine fructose agar. We amplified toxin A and B genes using primers NK9-NK 11 and NK104-NK105, respectively, in 23 C. difficile isolates. RESULTS: The concordance rate between ELFA and ELISA was 76.9%. The sensitivity and specificity of the ELFA and ELISA based on the culture and PCR results for toxin A gene were 84.6%/98.1% and 84.6%/67.3%. Positive and negative predictive values were 91%/96.2% in VIDAS and 78.0%/ 94.6% in TECHLAB. The positive rates of toxin B genes were 100%, 83.3% and 50% in toxin A positive, variant and negative strains, respectively. CONCLUSIONS: The sensitivities of the ELFA and ELISA for toxin A were the same, but specificity and positive predictive value of the ELFA were higher than those of the ELISA. PCR or EIA method detecting both toxin A and toxin B is strongly recommended, because the variant strains (toxin A negative and toxin B positive) of C. difficile may be more prevalent than were anticipated in Korea.
Agar ; Cefoxitin ; Clostridium difficile* ; Clostridium* ; Cycloserine ; Diagnosis ; Diarrhea ; Enzyme-Linked Immunosorbent Assay ; Fructose ; Genes, vif ; Immunoassay ; Immunoenzyme Techniques* ; Korea ; Polymerase Chain Reaction ; Sensitivity and Specificity

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