Reverse transcriptase mutations in HIV-1-infected children treated with zidovudine

Human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) mutations were detected in DNA from peripheral blood mononuclear cells from 11 of 12 HIV-1-infected children after 11-20 months of zidovudine monotherapy. The number of children with mutations detected at each codon were as follows: codon 41, 4; codon 67, 2; codon 70, 7; codon 215, 7; codon 219, 0. Codon 41 mutations were found only in the presence of a codon 215 mutation and in the absence of a codon 70 mutation. The codon 41/215 mutant combination was associated with decline in weight-for-age z score during therapy, weight < 10th percentile, CD4+ cell counts < 3rd percentile, and immune-complex dissociated HIV-1 p24 antigen (ICD p24 Ag) levels > 100 pg/ml. Patients developing the codon 70 mutation tended to have body weight > 30th percentile, CD4+ cell counts > 25th percentile, and ICD p24 Ag < 100 pg/ml. The codon 41 mutation was associated with clinical deterioration during a 6-month followup period.