[Prevalence of resistance to antiretroviral drugs in Spain]. / Prevalencia de resistencia a fármacos antirretrovirales en España.

INTRODUCTION: The development of resistance to antiretroviral therapy (ART) reduces the effectiveness of these drugs in HIV-infected children. METHODS: We performed a cross-sectional study in 86 vertically HIV-infected children, divided into four groups according to prior treatment: group 1: nucleoside reverse transcriptase inhibitor (NRTI), group 2: NRTI and non-nucleoside reverse transcriptase inhibitor (NNRTI), group 3: NRTI and protease inhibitor (PI), group 4: NRTI, NNRTI and PI. RESULTS: In group 1 (11 children), the median treatment duration was 35 months (26 to 108). Nucleoside-associated mutations (NAMs) were found in 10 of these patients and the Q151M multiresistance mutation was found in two. The three children in group 2 were treated for 9, 32 and 42 months with NRTI and NNRTI. One child showed three NAMs and another showed Q151M. Two children had the K103N mutation. Group 3 (36 children) received treatment with NRTI and PI for 48.0 +/- 27.6 and 23.0 +/- 14.6 months, respectively. NAMs were observed in 94 % of the patients in this group, and one child showed the Q151M mutation. In group 4 (36 children) total treatment duration was 70.0 +/- 36.1 months (13.0 +/- 12.1 months with NNRTI, and 39.0 +/- 14.3 months with PI). NAMs were observed in all patients in this group, and Q151M was found in three children. K103N and Y181C were detected in 24 (67%) and 10 (28%) of the children respectively, while 32 (90%) showed primary mutations to PI. CONCLUSIONS: A high prevalence of resistance mutations to NRTI and early appearance of resistance to NNRTI were observed in treated children.

Impact of long-term viral suppression in CD4+ recovery of HIV-children on Highly Active Antiretroviral Therapy.

BACKGROUND: The effects of HAART may differ between children and adults because children have a developing immune system, and the long-term immunological outcome in HIV-infected children on HAART is not well-known. A major aim of our study was to determine CD4+ evolution associated with long-term VL control during 4 years of observation on HAART. METHODS: We carried out a retrospective study on a cohort of 160 vertically HIV-infected children. It was carried out from 1996 to 2004 in six large Spanish pediatric referral hospitals. We compared 33 children who had long-term VL suppression (VL < or = 400 copies/ml) in the first 12 months of follow-up and maintained that level throughout follow-up (Responders-group), and 127 children with persistently detectable VL in spite of ART switches (Non-Responders-group). RESULTS: We observed a quick initial and significant increase in CD4+ counts from the baseline to 12 months on HAART in both groups (p < 0.01). The Non-Responders group sustained CD4+ increases and most of these children maintained high CD4+ level counts (> or = 25%). The Non-Responders group reached a plateau between 26% and 27% CD4+ at the first 12 months of follow-up that remained stable during the following 3 years. However, the Responders group reached a plateau between 30% and 32% CD4+ at 24, 36 and 48 months of follow-up. We found that the Responders group had higher CD4+ count values and higher percentages of children with CD4+ > or = 25% than the Non-Responders group (p < 0.05) after month 12. CONCLUSION: Long-term VL suppression in turn induces large beneficial effects in immunological responses. However, it is not indispensable to recover CD4+ levels.