Disparities in HIV continuum of care in the paediatric population: A real-life study in Brazil.

INTRODUCTION: Paediatric HIV follow-up is challenging, and treatment indicators are markedly far from Joint United Nations Programme on HIV/AIDS (UNAIDS) goals. In this study, we describe the 2019 Brazilian HIV cascade according to age categories and sociodemographic variables and address temporal trends between 2009 and 2019. METHODS: We obtained data from the Brazilian Ministry of Health monitoring database. Cascade outcomes included retention in care, antiretroviral use, and viral suppression. We assessed the effect of age on timely initiation of antiretroviral treatment (ART; initiation with CD4+ T-cell count ≥350 cells/mm3 or a first ART dispensation ≤30 days after the first CD4+ T-cell measurement) and detectable HIV viral load (>50 copies/mL) in univariable and multivariable analysis adjusted for sex, race, and social vulnerability index (SVI). Temporal trends in timely ART initiation and viral suppression were evaluated graphically. RESULTS: Among 771 774 people living with HIV, those in the youngest age categories had poorer indicators in the care cascade. Those in younger age groups, those with higher SVI, and those declaring Black and native Brazilian race/ethnicity had higher odds of having detectable viral load and delayed ART initiation. Although children living with HIV tend to start ART with higher CD4+ T-cell counts, time-series analysis suggests that improvements in treatment indicators seen in the adult population are not observed in the paediatric population. CONCLUSION: Our results highlight the challenges faced by children and adolescents living with HIV in achieving UNAIDS goals. Lower access to ART among children is a central barrier to improved paediatric care.

Allergen-specific IgG antibodies purified from mite-allergic patients sera block the IgE recognition of Dermatophagoides pteronyssinus antigens: an in vitro study.

One of the purposes of specific immunotherapy (SIT) is to modulate humoral immune response against allergens with significant increases in allergen-specific IgG levels, commonly associated with blocking activity. The present study investigated in vitro blocking activity of allergen-specific IgG antibodies on IgE reactivity to Dermatophagoides pteronyssinus (Dpt) in sera from atopic patients. Dpt-specific IgG antibodies were purified by ammonium sulfate precipitation followed by protein-G affinity chromatography. Purity was checked by SDS-PAGE and immunoreactivity by slot-blot and immunoblot assays. The blocking activity was evaluated by inhibition ELISA. The electrophoretic profile of the ammonium sulfate precipitated fraction showed strongly stained bands in ligand fraction after chromatography, compatible with molecular weight of human whole IgG molecule. The purity degree was confirmed by detecting strong immunoreactivity to IgG, negligible to IgA, and no reactivity to IgE and IgM. Dpt-specific IgG fraction was capable of significantly reducing levels of IgE anti-Dpt, resulting in 35%-51% inhibition of IgE reactivity to Dpt in atopic patients sera. This study showed that allergen-specific IgG antibodies purified from mite-allergic patients sera block the IgE recognition of Dermatophagoides pteronyssinus antigens. This approach reinforces that intermittent measurement of serum allergen-specific IgG antibodies will be an important objective laboratorial parameter that will help specialists to follow their patients under SIT.