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Background: Previous studies have shown that HIV- infected children have abnormal cerebral metabolites, measured by proton MR spectroscopy (1H MRS), but the stability of these measurements over time has not been described in HIV- infected children. The authors recently reported a study of cerebral metabolites in 20 HIV- infected children (6 to 16 years of age); the current study followed 12 of these children (10.0 years ± 3.7 years) and repeated the MR spectroscopy at 24.1 ± 3.7 weeks and 42.2 ± 3.5 weeks following the entry time with repeated neuropsychological testing. Methods: 1H MR spectra were acquired at 1.5 T (GE Signa, PRESS localization, repetition time = 3,000 msec, echo time = 30 msec). Five brain regions were studied: right frontal white matter, left frontal white matter, right basal ganglia, right hippocampus, and midfrontal gray matter. The concentrations of N- acetylaspartate (NAA), choline (CHO), creatine (CR), and myo- inositol (mI) and the ratio of each metabolite to CR were determined. Results: There were no changes in the metabolite concentrations or metabolite/CR ratios at the three time periods. Similarly, during this follow- up period, HIV- positive children showed no changes in clinical signs, HIV viral loads, CD4% , or CD4 counts, except for improved spatial memory with repeat testing. Conclusion: In a clinically and neurologically stable group of HIV- infected children, cerebral metabolites were stable over a 10- month time period, suggesting that it is possible to assess changes in cerebral metabolites as a measure of cerebral health, but longer follow- up in a larger sample is needed.
Background: Previous studies have shown that HIV-infected children have abnormal cerebral metabolites, measured by proton MR spectroscopy (1H MRS), but the stability of these measurements over time has not been described in HIV-infected children. The authors recently reported a study of current metabolites in 20 HIV-infected children (6 to 16 years of age); the current study followed 12 of these children (10.0 years ± 3.7 years) and repeated the MR spectroscopy at 24.1 ± 3.7 weeks and 42.2 ± 3.5 weeks following the Entry time with repeated neuropsychological testing. Methods: 1H MR spectra were acquired at 1.5 T (GE Signa, PRESS localization, repetition time = 3,000 msec, echo time = 30 msec) Five brain regions were studied: right frontal white matter, left frontal The concentrations of N-acetylaspartate (NAA), choline (CHO), creatine (CR), and myo- inositol (mI) and the ratio of each metabolite to CR were determined. Results: There were no changes in the metabolite concentrations or metabolite / CR ratios at the three time periods. Similarly, during this follow-up period, HIV- positive children showed no changes in clinical signs, HIV viral loads, CD4%, or CD4 counts, except for improved spatial memory with repeat testing. Conclusion: In a clinically and neurologically stable group of HIV-infected children, cerebral metabolites were stable over a 10- month time period, suggesting that it is possible to assess changes in cerebral metabolites as a measure of cerebral health, but longer follow-up in a larger sample is needed.