[Quantification of viremia in patients infected with human immunodeficiency virus with different degrees of immunosuppression]

Many of the therapeutical decisions related to patients infected with human immunodeficiency virus (HIV) are taken considering the CD4+ lymphocyte count. The recent availability of procedures which quantitate the number of viral particles in peripheral blood has disclosed that viremia degree is the best predictor of HIV disease progression. Nevertheless, the proportion of subjects who despite a normal CD4+ lymphocyte count, have a high viremia and a high risk of short term progression to AIDS is not well known.

Plasma viremia was investigated in 120 adults subjects with a known time of HIV infection. Fifty-two patients had a CD4+ lymphocyte count > 500 x 10(6)/l (CDC group 1), 42 had a number of CD4+ lymphocytes ranging from 200 and 500 x 10(6)/l (CDC group 2), and 26 had a count < 200 x 10(6)/l (CDC group 3). None of the patients was receiving antiretroviral treatment or had intercurrent infections at the time of the study.

Mean values of viremia showed an inverse significant relationship with the CD4+ lymphocyte count. In CDC group 1 subjects the distribution of viremia was as follows: low (< 3,000 copies of HIV RNA/ml) in 16 (30.8%), intermediate in 20 (38.4%), and high (> 30,000 copies of HIV RNA/ml) in 16 (30.8%). In eight subjects from CDC group 1, the duration of HIV infection was less than 5 years. In contrast, in patients from CDC group 3, viremia was high in 17 (65.4%), intermediate in 9 (34.6%), and none of them had a low degree viremia. In CDC group 2 patients, viremia was high in 14 (33.3%), intermediate in 20 (47.6%), and low in 8 (19.1%).

There is an inverse correlation between the viremia degree and the CD4+ lymphocyte count among HIV-positive patients. Nevertheless, there can be a high viremia in absence of low CD4+ lymphocyte count, particularly among subjects with HIV infection for less than 5 years, in whom an early therapeutical intervention might be warranted.