The differences in profiles of HIV mutational drug resistance between paired plasma samples and culture isolates were analyzed in treated and untreated HIV-infected patients. The DNA sequence of the entire protease gene and codons 1-320 of the reverse transcriptase gene was analyzed from the paired plasma samples and viral isolates. Differences in the distribution of resistance mutations from the two sources were detected in 13 of 14 patients receiving antiretroviral therapy. Some excess mutations, observed in plasma samples but not in culture isolates, are reportedly associated with resistance to antiretroviral drugs. These results emphasize the need for standardization and clinical laboratory use of phenotypic assays that avoid extensive cocultivation.
Copyright 2002 S. Karger AG, Basel