Incomplete recovery of the CD4+/CD8+ ratio is associated with the late introduction of antiretroviral therapy among people living with HIV infection

ABSTRACT Despite being subject to lower AIDS-related mortality rates and having a higher life expectancy, patients with HIV are more prone to develop non-AIDS events. A low CD4+/CD8+ ratio during antiretroviral therapy identifies people with heightened immune senescence and increased risk of mortality. In clinical practice, finding determinants of a low CD4+/CD8+ ratio may be useful for identifying patients who require close monitoring due to an increased risk of comorbidities and death. We performed a prospective study on the evolution of the CD4+/CD8+ ratio in 60 patients infected with HIV (80% males), who were subjected to two different antiretroviral regimens: early and deferred therapy. The initial CD4+/CD8+ ratio was ≤1 for 70% of the patients in both groups. Older age, CD4+ cell count at inclusion, Nadir CD8+T-cell count, and Initial CD4+/CD8+ ratio ≤ 1 were risk factors for lack of ratio recovery. In the multivariate analysis, a CD4+/CD8+ ratio > 1 at the start of the treatment was found to be a determinant factor in maintaining a CD4+/CD8+ ratio > 1. The nadir CD4+T-cell count was lower in the deferred therapy group (p=0.004), and the last CD4+/CD8+ ratio ≤1 was not associated with comorbidities. Ratio recovery was not associated with the duration of HIV infection, time without therapy, or absence of AIDS incidence. A greater improvement was observed in patients treated early (p=0.003). In contrast, the slope of increase was slower in patients who deferred treatment. In conclusion, the increase in the CD4+/CD8+ ratio occurred mostly for patients undergoing early strategy treatment and its extension did not seem to be related to previous HIV-related factors.

The role of IFN-γ production during retroviral infections: an important cytokine involved in chronic inflammation and pathogenesis

ABSTRACT Interferon-gamma (IFN-γ) plays a crucial role in viral infections by preventing viral replication and in the promotion of innate and adaptive immune responses. However, IFN-gamma can exert distinct effects in different persistent viral infections. The long-term overproduction of IFN-γ in retroviral infections, such as the human immunodeficiency virus (HIV), human T-lymphotropic virus type 1 (HTLV-1), and human endogenous retroviruses (HERVs), resulting in inflammation, may cause neuronal damage. This review is provocative about the role of IFN-γ during persistent retroviral infections and its relationship with the causation of some neurological disorders that are important for public health.

Mortalidade por pneumonia em crianças brasileiras até 4 anos de idade / Pneumonia mortality in Brazilian children aged 4 years and younger

OBJETIVO: Avaliar a tendência de mortalidade por pneumonia em crianças brasileiras até 4 anos de idade no período de 1991 a 2007. MÉTODOS: Foi realizado um estudo retrospectivo baseado em banco de dados do Departamento de Informática do Sistema Único de Saúde (DATASUS), do qual foram extraídos o número de óbitos por pneumonia e a população residente de até 4 anos de idade nas cinco regiões brasileiras e no país como um todo. O coeficiente de mortalidade foi calculado pelo número de óbitos por pneumonia dividido pela população, multiplicando por 1.000 na faixa etária menor de 1 ano e por 10.000 na faixa etária de 1 a 4 anos. Utilizou-se o teste de regressão linear para avaliar a tendência temporal de mortalidade. RESULTADOS: Observou-se um decréscimo significativo de mortalidade por pneumonia no período estudado em ambas as faixas etárias e em todas as regiões do país. No Brasil como um todo, a redução média anual dos coeficientes de mortalidade na população menor de 1 ano e naquela entre 1 e 4 anos foi de 0,12 e 0,07, respectivamente. As Regiões Sul e Sudeste apresentaram as maiores reduções (-0,14 e -0,18 para < 1 ano; -0,07 e -0,09 para 1 a 4 anos). As menores reduções foram nas Regiões Norte e Nordeste (-0,04 e -0,07) nas crianças menores de 1 ano, e nas Regiões Norte e Centro-Oeste (-0,03 e -0,04) na faixa etária entre 1 e 4 anos. CONCLUSÕES: Houve uma redução significativa na mortalidade por pneumonia em crianças até 4 anos de idade em todo o país no período de 1991 a 2007, porém, uma discrepância entre as diferentes regiões permanece em evidência.

OBJECTIVE: To evaluate the trend of pneumonia mortality in Brazilian children aged 4 years and younger from 1991 to 2007. METHODS: We conducted a retrospective study based on the database of the IT Department of the Brazilian Unified Health System (DATASUS), from which we obtained the number of deaths from pneumonia and the population aged 4 years and younger living in the five Brazilian regions and in the whole country. Mortality rate was calculated according to the number of deaths from pneumonia divided by the population, multiplied by 1,000 for the age group under 1 year old and by 10,000 in the age group from 1 to 4 years. The linear regression test was used to evaluate the time trend of mortality. RESULTS: There was a significant decrease in pneumonia mortality rates during the study period in both age groups and all regions of the country. In Brazil, the mean annual reduction in mortality rates in the population under 1 year old and between 1 and 4 years was 0.12 and 0.07, respectively. The South and Southeast regions showed the greatest reductions (-0.14 and -0.18 for < 1 year and -0.07 and -0.09 for 1 to 4 years). The smallest decreases were in the North and Northeast regions (-0.04 and -0.07) in children younger than 1 year, and in the North and Central West (-0.03 and -0.04) in the age group between 1 and 4 years. CONCLUSIONS: There was a significant reduction in pneumonia mortality in children aged 4 years and younger across the country from 1991 to 2007; however, a discrepancy between the different regions remains evident.