Detection of Varicella-Zoster Virus (VZV) by Nested Polymerase Chain Reaction / 임상검사와정도관리

BACKGROUND: Polymerase chain reaction (PCR) is known as a sensitive and specific method for the detection of varicella-zoster virus (VZV). Nested PCR is reliably used than conventional PCR to increase the sensitivity and specificity, especially in cases of small sized tissue samples. METHODS: We detected VZV infection in tissues from 111 patients using conventional PCR and nested PCR. Ninety-one cases of fresh tissues and twenty cases of formalin-fixed paraffin-embedded (FFPE) tissues were evaluated. The column method or home made lysis buffer method was used for the DNA extraction of fresh tissues and FFPE tissues. RESULTS: Among total 111 cases, VZV were detected in 62 (55.9%) cases by conventional PCR and 79 (71.2%) cases by nested PCR. The detection rate of nested PCR was higher than conventional PCR (1.27 folds). In 91 cases of fresh tissues, 56 (61.5%) were positive by conventional PCR and 68 (74.7%) by nested PCR. In 20 cases of FFPE tissues, 6 (30%) were positive by conventional PCR and 11 (55%) by nested PCR. The detection rate of VZV was increased by nested PCR both in fresh tissues (1.21 folds) and FFPE tissues (1.83 folds). CONCLUSIONS: Nested PCR is the more sensitive method than conventional PCR for the detection of VZV infection in tissues regardless of DNA extraction methods, especially for the small sized FFPE tissues.

Laboratory Evaluation of the LG HCD 3.0TMB (LG HCD3.0 plus) for the Detection of HCV Antibodies / 대한임상병리학회지

BACKGROUND: The purpose of this study was to evaluate the newly improved third generation enzyme immunoassay kit, LG HCD 3.0TMB (LG Chemical Ltd., Korea) for the detection of antibodies for the hepatitis C virus. METHODS: The 1,068 clinical samples and 3 seroconversion panels were subjected to compare LG HCD 3.0TMB with Ortho HCV 3.0. The discordant clinical samples were confirmed by RT-PCR (Roche Amplicor HCV test) and RIBA (LG HCD confirm, Ortho RIBA HCV 3.0). Reproducibility was estimated using six samples with different anti-HCV levels for each assay. RESULTS: In clinical samples, concordance between LG HCD 3.0TMB and Ortho HCV 3.0 was 98.8% (1,055 of 1,068 tests) in the screening test. After a repeat test of 13 discordant samples, overall concordance was 99.3% (1,061 of 1,068 tests). In the seroconversion panel testing, the LG HCD 3.0TMB detected HCV antibodies earlier than the Ortho HCV 3.0 in one of the three panels. Results of both EIA assays were constant on the reproducibility test. CONCLUSIONS: Based on the good agreement with Ortho HCV 3.0 and superior seroconversion sensitivity, the LG HCD 3.0TMB assay appears to be suitable for detecting HCV antibodies in clinical laboratories.