Sigma-Metrics of Electrolyte Tests From a Recently Launched New-Generation Proficiency Testing Program of the Korean Association of Quality Assurance for Clinical Laboratory

No abstract available.

Establishment and Multicenter Evaluation of a National Reference Panel for Syphilis Antibodies in Korea

BACKGROUND: Establishment of a national reference panel for syphilis antibodies is necessary to evaluate the performance of in-vitro diagnostic tests for syphilis and to verify test quality. This study aimed to establish a national reference panel for syphilis antibodies, to assess the suitability of a panel for non-treponemal and treponemal testing, and to assess the reactivity of the various tests currently in use. METHODS: Treponemal pallidum particle agglutination (TPPA)-positive and -negative fresh frozen plasma samples were obtained. After the fresh frozen plasma was converted to serum by defibrination, the samples were pooled. Two candidate reference standards containing no syphilis antibodies and 10 candidate reference standards containing syphilis antibodies were prepared on the basis of reactivity in the TPPA assay. Candidate reference standards were tested by three laboratories using five non-treponemal tests and four treponemal tests. RESULTS: All three laboratories reported positive non-treponemal test results for the mixed-titer performance panel (MP)/6-MP/12. MP/1, MP/2, and MP/3 were negative for non-treponemal tests. MP/4 and MP/5 were reported either as positive or negative according to the laboratories. All laboratories reported positive TPPA results for MP/3-MP/12 and negative results for MP/1 and MP/2. No significant difference was detected among the treponemal testing results in three laboratories. CONCLUSIONS: We established 12 candidate national reference standards containing various concentrations of syphilis antibodies. A collaborative study using nine tests demonstrated that 12 candidate national reference standards presented consistent results, except a few assays with low sensitivity, and thus could be used as a national reference panel for syphilis antibody testing.

Analysis of the Reentry Test Results of the HCV Deferred Donors / 대한수혈학회지

BACKGROUND: The donor deferral registry (DDR) program has been operating since 2004. The donors who registered in the DDR are prohibited from donating blood. But some of them can enter the eligible donor group if they pass a reentry test. We analyzed the results of the reentry tests for the HCV deferred donors. METHODS: A total of 587 donor samples were tested during 18 months (July. 2007~December. 2008). Anti-HCV (ARCHITECT HCV, Abbott, Wiesbaden, Germany), RIBA (LG HCD confirm, LG Life Sciences, Daejeon, Korea), and HCV RNA (PCR with COBAS AMPLICOR HCV, Roche, Molecular Systems, Inc. Branchburg, USA) were used for detection. The donors showing negativity for all the test items were released from the DDR. RESULTS: Among the 587 subjects, 466 (79.4%) of the donors who showed negative results on the tests were released from DDR. The donors who showed variable positive results for the tests were not released. Only 15 donors of 121 donors showed positive or indeterminate (ID) results according to the anti-HCV, RIBA and the PCR results. CONCLUSION: Those people with RIBA ID with negative results in anti-HCV and PCR results were unnecessarily kept on the retained in DDR unnecessarily. The algorithm of the reentry test for HCV deferred donors seems to needs to be reevaluated to for the saveing eligible donors.

Cytogenetic evaluation of a patient with ring chromosome 9 presenting failure to thrive and developmental delay / 소아과

We report clinical, cytogenetic, and fluorescence in situ hybridization (FISH) studies of a patient with ring chromosome 9. She presented with failure to thrive, facial dysmorphysm and mild psychomotor development delay in the absence of major malformations. Peripheral blood karyotype of the patient was 46,XX,r(9)(p24q34). G-band analysis suggested no loss of material in the ring chromosomes. FISH analysis using the subtelomere-specific sequences on chromosome 9p and 9q, revealed 46,XX,r(9)(p24q34),ish r(9)(D9S913-,D9S325+). Failure to detect any hybridization of a probe for the subtelomeric sequences in the ring 9p terminal suggested that this ring arose from breakage in the distal short arm. The cytogenetic and FISH data in our case provided further evidence for the existence of a "complete ring" phenotype with incomplete subtelomeric sequences.

The Clinical Significance of Prenatal Antibody Screening Test / 대한수혈학회지

BACKGROUND: It is recommended that ABO, Rh typing and unexpected antibody screening should be tested during pregnancy in order to prevent hemolytic disease of the newborn (HDN). However, it is unclear that a routine prenatal antibody screening test predicts the occurrence of HDN. We performed a retrospective study to determine the frequency of unexpected antibody during pregnancy, antibody specificity, and the usefulness of prenatal antibody screening as a predictor of HDN. METHODS: All 6,293 prenatal antibody screening were tested at Eulji hospital from April 1997 to December 2002. The results of antibody screening and identification test were reviewed in laboratory sheet. The past transfusion and pregnant history and postnatal HDN evidence were reviewed in pregnant women with positive antibody screening. A commercial two cell panel, Selectogen I, II, and panel cell (Ortho Diagnostic Systems Inc., Raritan, USA) were used with tube method until March 1999. In April 1999, reagent cells were changed to a gel agglutination test with ID-Diacell I, II and ID-Dia Panel of DiaMed-ID Micro Typing System (DiaMed AG, Cressier, Switzerland). RESULTS: Positive results of antibody screening test were found in 52 cases (0.83%, 52/6,293). Only 28 cases of them were tested antibody identification. Antibody specificity was identified at 22 cases and 17 (77.3%, 17/22) women had unexpected antibodies which are not associated with HDN. They were 11 with anti-Lea , 3 with anti-Leb, and 3 with anti-P1. The others were 3 cases of anti-E, 1 of anti-M, and 1 of anti-S. However, no one had evidence of HDN. CONCLUSION: These results suggest that routine prenatal antibody screening may not be necessary for all pregnant women except Rh (D) negative women or those who have a history of HDN.

Evaluation of HLC-723 G7 Hemoglobin A1c Autoanalyzer / 임상검사와정도관리

BACKGROUND: We evaluated the performance and analysis time of HLC-723 G7 (Tosoh corp. Tokyo, Japan) hemoglobin (Hb) A1c autoanalyzer. It utilizes cation exchange high performance liquid chromatography (HPLC) method and has a reduced analysis time compared with that of an earlier model HLC-723GHb V A1c 2.2(TM) (HLC-723GHb V, Tosoh corp. Tokyo, Japan). METHODS: We evaluated linearity, precision and comparison with HLC-723GHb V following NCCLS guidelines and counted the number of tests per hour to estimate analysis time. RESULTS: Linearity through the range from 5.8% to 13.9% was good (r2=0.9930, relative nonlinearity <2.5%). The within-run coefficients of variation (CVs) for groups of low, middle, and high level were 1.09%, 0.76%, and 0.68% and total CVs for each group were 1.60%, 0.91%, and 1.00%, respectively. Correlation equation between HLC-723 G7 and HLC-723GHb V was HLC-723 G7=1.0308 (HLC-723GHb V)-0.2896 %Hb A1c (r=0.9992, P<0.0001). Analysis time of HLC-723 G7 was 1.2 minutes per test compared with 2.1 minutes of HLC-723GHb V. CONCLUSIONS: HLC-723 G7 showed the acceptable performance and shortening analysis time therefore, it was suitable for reducing turn around time of Hb A1c assay.

A Case of Identification of Marker Chromosome by comparative genomic hybridization and fluorescence in situ hybridization / 대한임상병리학회지

Comparative genomic hybridization (CGH) has been used to identify deletions and amplifications, particularly in neoplastic samples. CGH provides a new possibility searching genomes for imbalances of genetic material. We described the combined use of CGH and fluorescence in situ hybridization (FISH) to identify the origin of a marker chromosome in a child with mental retardation. Giemsa banding of metaphases from cultured lymphocytes showed a marker chromosome. The Karyotype was 47,XX,+mar. CGH revealed that the additional material originated from 15q. FISH confirmed this finding with whole chromosome paint for chromosome 15 and with a D15S10 (15q11-13) probe. This case demonstrates the efficient use of CGH and confirmatory FISH for the identification of chromosomal material of unknown origin.

A Case of mos 45,X/46,X, +mar. ish der(X)(wcpX+) Turner Syndrome / 대한임상병리학회지

Turner syndrome is a genetic disorder that affects about 1/2,000-1/5,000 females born. The typical female with Turner syndrome has only one X chromosome in each of her cells. There are several variations on this theme as other similar chromosome anomalies occur in females with Turner syndrome. We observed a patient with short stature, abscent vagina and chromosomal abnormality. Chromosomal analysis of the patient showed 45,X/46,X, +mar. The marker chromosome was revealed as X chromosome in fluorescent in situ hybridization (FISH). We report a case of mos 45,X/46,X,+mar.ish der(X)(wcp X+) in Turner syndrome with a brief review of literature.

Analysis of Apolipoprotein E Genotypes in Several Demential diseases / 대한임상병리학회지

BACKGROUND: An increased frequency of the epsilon4 allele in Alzheimer's disease has been reported, which suggested a functional role of apolipoprotein E isoforms in pathophysiology of Alzheimer's disease. The aims of this study were to determine the frequency of ApoE genotypes in various types of dementia such as Alzheimer's disease, vascular dementia, and Parkinson's disease, to relate epsilon4 and assess risk factors for different types of dementia. METHODS: We assessed the frequency of Apolipoprotein E alleles in 29 patients with Alzheimer's disease, 10 patients with vascular dementia and 9 demented patients with Parkinson's disease. The Apolipoprotein E genotype was determined the polymerase chain reaction (PCR) with sequence-specific oligonuculeotide primers (SSOP) and reverse hybridiza- tion using the INNO-LiPA (Line Probe Assay) Apo E typing kit. RESULTS: Allele frequencies of epsilon2, epsilon3, and epsilon4 were : 0.5, 0.72, and 0.23 in Alzheimer's disease; 0, 0.65, and 0.35 in vascular dementia; 0.6, 0.83 and 0.11 in demented patients with Parkinson's disease. Conculsion : These results indicate that the apolipoprotein E4 allele is associated with not only Alzheimer's disease but also vascular dementia, however not associated with Parkinson's disease. No such an association was observed between the apolipoprotein E alleles and age.