Viral load testing of human immunodeficiency virus (HIV) is an essential tool for initiating and monitoring the antiretroviral therapy for HIV patients. To this end, several methods including polymerase chain reaction (PCR), branched DNA (bDNA), nucleic acid sequence based amplification assay (NASBA) and internally controlled virion PCR (ICV PCR) have become available. Of these methods, the standard reverse transcription-PCR (RT-PCR) assay has been widely used in Korea. However, no comparison study has been performed among the various detection methods currently used in Korean patients. We evaluated the correlation and agreement between the PCR and the branched DNA (bDNA) assay for measurement of HIV RNA in Korean patients. Eighty randomly selected samples from HIV-1-seropositive patients visiting Yonsei Medical Center Severance Hospital were studied. We found that these assays show good agreement, have a reliable correlation (r = 0.92, mean difference in log10 copies/ mL +/- 2 standard deviation = 0.098 +/- 0.805) and produce values whose relationship is given by the following equation: log10v3 bDNA = -0.3405 + 1.0601 x log10RT-PCR. Thus, we conclude that these two methods may allow direct comparison of the results obtained from different assay systems.
Comparative Study ; DNA/chemistry* ; DNA/analysis* ; Genetic Techniques/standards* ; HIV-1/genetics* ; Human ; Korea ; RNA, Viral/blood* ; Reverse Transcriptase Polymerase Chain Reaction/standards*

BACKGROUND: The aims of this study were to compare several DNA extraction methods and 16S rDNA primers and to evaluate the clinical utility of broad-range PCR in continuous ambulatory peritoneal dialysis (CAPD) culture fluids. METHODS: Six type strains were used as model organisms in dilutions from 10(8) to 100 colony-forming units (CFU)/mL for the evaluation of 5 DNA extraction methods and 5 PCR primer pairs. Broad-range PCR was applied to 100 CAPD culture fluids, and the results were compared with conventional culture results. RESULTS: There were some differences between the various DNA extraction methods and primer sets with regard to the detection limits. The InstaGene Matrix (Bio-Rad Laboratories, USA) and Exgene Clinic SV kits (GeneAll Biotechnology Co. Ltd, Korea) seem to have higher sensitivities than the others. The results of broad-range PCR were concordant with the results from culture in 97% of all cases (97/100). Two culture-positive cases that were broad-range PCR-negative were identified as Candida albicans, and 1 PCR-positive but culture-negative sample was identified as Bacillus circulans by sequencing. Two samples among 54 broad-range PCR-positive products could not be sequenced. CONCLUSIONS: There were differences in the analytical sensitivity of various DNA extraction methods and primers for broad-range PCR. The broad-range PCR assay can be used to detect bacterial pathogens in CAPD culture fluid as a supplement to culture methods.
Bacillus/genetics/isolation & purification ; Bacteria/genetics/*isolation & purification ; Candida albicans/genetics/isolation & purification ; DNA Primers/genetics ; DNA, Bacterial/*analysis/isolation & purification ; *Genetic Techniques/standards ; Humans ; Peritoneal Dialysis, Continuous Ambulatory ; Peritonitis/*microbiology ; Polymerase Chain Reaction ; Reagent Kits, Diagnostic ; Sequence Analysis, DNA