Drug resistance in children and adolescents with HIV in Panama

OBJECTIVES: The inadequacy of resistance monitoring in Latin America leads to circulation of HIV strains with drug resistance mutations (DRMs), compromising ART effectiveness. This study describes the DRM prevalence in HIV-infected paediatric patients in Panama. METHODS: During 2018–19, plasma was collected from 76 HIV-infected children/adolescents (5 ART-naive, 71 treated) in Panama for HIV-1 DRM pol analysis, predicted antiretroviral (ARV) susceptibility by Stanford, and HIV-1 variant phylogenetic characterization. RESULTS: HIV-1 pol sequences were recovered from 67 (88.2%) of 76 children/adolescents (median age 12 years), carrying 65 subtype B, 1 subtype G and 1 unique recombinant URF_A1B. Five were ART-naive and 62 ART-treated under virological failure (viraemia >50 copies/mL) with previous exposure to NRTIs, (100%), NNRTIs (45.2%), PIs (95.2%) and integrase strand transfer inhibitors (INSTIs, 17.7%). Among the treated patients, 34 (54.8%) carried resistant strains, with major DRMs to one (40.3%), two (9.7%) or three (4.8%) ARV families. Most of them harboured DRMs to NRTIs (58.5%) or NNRTIs (39%), but also major DRMs to PIs (4.9%) and INSTIs (6.5%). We also found dual-class NRTI + NNRTI (12.2%) and NNRTI + PI (2.6%) resistance. Two naive subjects carried viruses with DRMs to NRTIs and NRTI + NNRTI, respectively. Sequenced viruses presented high/intermediate resistance mainly to emtricitabine/lamivudine (48.9% each) and efavirenz/nevirapine (33.3% each). Most participants were susceptible to PIs (91.3%) and INSTIs (88.1%). CONCLUSIONS: The high DRM prevalence to NRTIs and NNRTIs observed among treated HIV-infected children/adolescents in Panama justifies the need for routine resistance monitoring for optimal rescue therapy selection in this vulnerable population.