002). More than 90% of the children had not been
immunized against VZV: their anti-VZV IgG levels presumably resulted from wild-type infection. The median anti-VZV IgG titre was 264 IU/L [interquartile range (IQR) 747 IU/L] in HIV-infected children and 1535 IU/L (IQR 1600 IU/L; P<0.001) in the adults (Fig. ALK inhibitor 1), even after exclusion of VZV-seronegative, possibly unexposed individuals (P<0.001). Twenty-one per cent (20 of 97) of the HIV-infected children had undetectable VZV antibodies, compared with 3% (two of 78; P<0.001) of the adults. At baseline, differences in anti-VZV IgG level, HIV RNA level, CD4 cell count and CD4 percentage between HIV-infected children and adults were already significant (P<0.001, <0.001,
<0.001 and 0.001, respectively) (data not shown). In this cross-sectional analysis, none of the following variables was predictive of lower anti-VZV IgG levels in HIV-infected children: age, gender, ethnicity, CD4 T-cell count and percentage, HIV RNA level, age at initiation of HAART, absence/presence of HAART and duration of HAART. To determine whether anti-VZV antibodies declined more rapidly in HIV-infected children than adults, we assessed the change in antibody titres over time in all subjects who initially had negative VZV antibodies GSI-IX cost and then became positive following exposure (484 samples from 85 children and 435 samples from 77 adults). Twenty per cent (17 of 85) of previously VZV-positive children failed to maintain anti-VZV IgG levels >50 IU/L, compared with 2.6% (two of 77; P<0.001) of adults. The odds ratio for
antibody waning in children, adjusted for the CD4 cell count, was 17.74 [P<0.001; 95% confidence interval (CI) 4.36–72.25]. These 17 HIV-infected children were compared with 54 randomly selected age-matched HIV-infected children who maintained anti-VZV IgG levels >50 IU/L throughout the study period. The two groups were comparable in terms of gender, age, CD4 T-cell count and duration of HAART. Univariate analyses demonstrated that higher HIV RNA level (P=0.001), absence of HAART (P=0.037) and lower CD4 percentage (P=0.027) were significantly associated with failure to maintain VZV antibodies. In the multivariate analysis, only higher HIV RNA level remained significant (P=0.011). Cell press Longitudinal analyses showed that the trend of anti-VZV IgG level over time was not significant in adults (Fig. 2). Anti-VZV IgG levels were lower in children at all time-points (P<0.001), but did not decline more rapidly than in adults and even slightly increased over time (P=0.01). This remained true after adjusting for age. Thus, the failure of 20% of HIV-infected children to maintain anti-VZV antibodies did not reflect a general pattern of antibody loss in HIV-infected children. The lower anti-VZV IgG levels in HIV-infected children could result from weak primary anti-VZV responses.
Related posts: