Comparison of Two Commercial Real-time Nucleic Acid Amplification Methods for Detecting the Viral Load of Human Immunodeficiency Virus Type 1

Kim, Sue Jung; Lee, Eunkyung; Park, Younhee; Kim, Hyon Suk

Abstract

BACKGROUND
Detection of the viral load of Human Immunodeficiency Virus type 1 (HIV-1) RNA is important for clinical decision making and for determining the prognosis of HIV-infected patients. The aim of the study is to compare the performance of real-time RT-PCR (COBAS AmpliPrep/COBAS TaqMan HIV-1, CAP/CTM, Roche Diagnostics) and the Nucleic Acid Sequence Based Amplification (NucliSens EasyQ HIV-1, NucliSens, BioMerieux) methods for testing Korean HIV-infected patients.
METHODS
Among the specimens that were requested to undergo HIV-1 RNA viral load detection from 2005 to 2006, 153 specimens were selected based on the status of the specimens. The CAP/CTM and NucliSens tests were performed according to the manufacturer's instruction.
RESULTS
HIV-1 RNA was detected by both tests in 93 specimens. Among the remainder, CAP/CTM detected HIV-1 RNA in 10 specimens, while the same specimens showed results lower than the detection limit with using the NucliSens. Though the results were appropriately correlated (r=0.85, P<0.0001), the mean differences between the two test results were -0.1321 log(10) IU/mL on the Bland-Altman test.
CONCLUSION
The methodologic difference or the presence of a HIV subtype may affect the agreement between the two tests. The standardization of methods and the establishment of a linear range for the individual laboratory results may be helpful to obtain accurate test results.