Molecular phylogenetics of transmitted drug resistance in newly diagnosed HIV Type 1 individuals in Denmark: a nation-wide study.

Highly active antiretroviral treatment is compromised by viral resistance mutations. Transmitted drug resistance (TDR) is therefore monitored closely, but follow-up studies of these patients are limited. Virus from 1405 individuals diagnosed with HIV-1 in Denmark between 2001 and 2009 was analyzed for TDR, and molecular-epidemiological links and progression of the infection were described based on data from standardized questionnaires, the prospective Danish HIV Cohort Study, and by phylogenetic analysis. Eighty-five individuals were found to be infected with virus harboring mutations resulting in a prevalence of 6.1%, with no changes over time. The main resistance mutations were nucleoside reverse transcriptase inhibitor (NRTI) mutation 215 revertants, as well as nonnucleoside reverse transcriptase inhibitor (NNRTI) mutation 103N/S and protease inhibitor (PI) mutations 90M and 85V. Phylogenetic analysis confirmed 12 transmission chains involving 37 TDR individuals. Of these 21 were also documented epidemiologically. The virus included in the transmission chain carried similar resistance mutations to the TDR index case, whereas controls chains from index cases without TDR were generally without resistance mutations. We observed no difference in progression of the infection between individuals infected with TDR and individuals infected with wild-type HIV-1. The prevalence of TDR is low in Denmark and transmission of dual-drug-resistant HIV-1 is infrequent. The TDR isolates were shown to originate from local patients failing therapy.

The incidence rate of HIV type-1 drug resistance in patients on antiretroviral therapy: a nationwide population-based Danish cohort study 1999-2005.

BACKGROUND: Newer antiretroviral treatment regimens for HIV carry a lower risk of inducing drug resistance mutations. We estimated changes in incidence rates (IRs) of new mutations in HIV-infected individuals receiving highly active antiretroviral therapy (HAART). METHODS: Population-based data were obtained from the Danish HIV Cohort Study and the Danish HIV Sequence Database. We included treatment-naive patients initiating HAART after December 1997 and computed time to first drug resistance mutation, identified as new mutations detected within 1 year after a 60-day period of treatment failure (HIV RNA>1,000 copies/ml). We estimated annual IRs of new resistance mutations towards nucleoside reverse transcriptase inhibitors (NRTIs), non-NRTIs (NNRTIs) and protease inhibitors (PI), and of new specific resistance mutations. RESULTS: A total of 1,829 individuals were observed for 7,294 person-years at risk (PYR). The IR of NRTI resistance decreased from 13.1 per 1,000 PYR (95% confidence interval [CI] 4.9-35.0) in 1999 to 3.7 (1.9-7.2) in 2004-2005 (test for trend P=0.024). The IR of NNRTI resistance decreased from 15.4 (2.2-109.6) in 1999 to 7.9 (4.6-13.6) in 2004-2005 (P=0.077). The IR of PI resistance decreased from 7.5 (1.4-21.8) in 1999 to 2.9 (0.7-11.4) in 2002-2003 (P=0.148). The IRs were low for specific resistance mutations, except for M184V (IR 5.6 [4.0-7.9]) and K103N (IR 8.2 [5.6-12.0]). CONCLUSIONS: The incidence of acquired drug resistance has decreased among HIV-infected patients treated with HAART in Denmark during 1999-2005.

Follow-up of a multi-drug resistant HIV-1 infected patient successfully treated with darunavir and etravirine.

A multi-drug-resistant, non-compliant HIV-1 patient was treated successfully with a combination of the drugs darunavir and etravirine for more than 8 months. The patient experienced an immunoreconstitution syndrome due to improved compliance. Examining previous resistance tests for this type of patient is valuable when assigning new medication.