Rapid detection of drug resistant HIV -1 to reverse transcriptase and protease inhibitors in HIV-infected patients receiving highly active antiretroviral therapies.

Objective: To develop and validate a rapid and sensitive method that can be used to detect emergence of HIV-1 drug resistant viruses in HIV-infected patients receiving highly active antiretroviral therapies (HAART).

Methods: HIV-1 viral RNA was extracted from plasma and amplified by nested RT-PCR. Nucleotide sequences of the reverse transcriptase (RT) and protease (PR) genes were determined by automated DNA sequencing.

Results: RT and PR sequences can be reliably determined with a minimum 2,000 copies/ml of viral RNA in plasma. Emergence of drug resistant viruses can he detected as soon as it reached to > 25% of the total viral populations. By using this method, drug-resistant viral populations were found to correlate with rebound of viral RNA level after prolonged antiretroviral therapies in HIV-infected children.

Conclusions: This rapid and sensitive HIV-1 genotyping method can be used to predict and confirm emergence of HIV-1 drug resistance in HIV-infected patients receiving HAART.