Background: The CD4+ lymphocytes are the principal target cell for the human immunodeficiency virus (HIV). Their depletion originates a very severe cell immunosuppression, which conditions the appearance of opportunistic infections and neoplasms characteristic of AIDS. The aim of this study was to evaluate whether there is a relation between the degree of cell immunosuppression and the type of opportunistic infections and neoplasms which these patients develop in Spain.
Methods: The CD4+ lymphocyte counts in 400 adults with HIV infection who developed opportunistic infections or neoplasms were retrospectively reviewed (1987-1991). This determination was carried out during between two months prior to diagnosis of AIDS (CDC, 1987) to one month after such diagnosis.
Results: The results allowed opportunistic infections to be classified into three groups according to the grade of immunosuppression: 1) opportunistic infections with more than 0.2 x 10(9) CD4+ lymphocytes/l (45-60% of cases of tuberculosis, esophageal candidiasis and enteritis by Isospora belli); 2) opportunistic infections with 0-0.2 x 10(9) CD4/l (87-100% of the cases of pneumonia by Pneumocystis carinii, encephalic toxoplasmosis, visceral leishmaniasis and enteritis by Cryptosporidium); 3) opportunistic infections with 0-0.1 x 10(9) CD4 lymphocytes/l (70-100% of the cases of systemic cryptococcosis, retinitis by cytomegalovirus, progressive multifocal leukoencephalopathy and infection by Mycobacterium avium-intracellulare). With respect to the neoplasms, Kaposi's sarcoma was observed in patients with different degrees of immunosuppression. Seventy-five and 80% of the patients with non Hodgkin's lymphoma and primary cerebral lymphoma had less than 0.2 x 10(9)/l and less than 0.1 x 10(9)/l CD4+ lymphocytes, respectively.
Conclusions: The CD4 lymphocyte counts may predict the type of opportunistic infections which patients with the human immunodeficiency virus infection may develop.