time course of opportunistic diseases in patients with human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS).
There is a stereotypical time course for the development of opportunistic processes in patients with HIV infection. The risk for these disorders increases when the CD4 count falls to less than 200. For some processes, such as lymphoma and tuberculosis, presentation may occur at a CD4 count of more than 200. Cytomegalovirus (CMV) infection, cryptosporidia, microsporidia, and Mycobacterium avium complex (MAC) occur when the CD4 count is less than 100 and often less than 50.