PI Perspective #23

November 1997     View PDF     En español

PHS Guidelines on Opportunistic Infections

The U.S. Public Health Service (PHS) recently issued new guidelines for the prevention (prophylaxis) and maintenance (to prevent recurrence) of opportunistic infections (OIs). The availability of highly active antiretroviral therapies (HAART) has significantly decreased the incidence of opportunistic infections, as these medications help the immune system recover or delay immune deterioration.

However, it is still not known whether increases in CD4+ cell counts as a result of HAART and/or an immune based therapies, like interleukin-2 (IL-2), can provide complete protection against opportunistic infections. There have been some reports that people whose CD4+ cells counts have increased, have stopped their maintenance therapies and have not yet had their OI reoccur. However, many researchers believe that the specific types of CD4+ cells, which provide protection against specific OIs, may be lost due to immune deterioration and these cells do not necessarily return, at least in the short term, as a product of HAART. Researchers agree that there is likely to be much individual variation in these regards, probably based on the degree of immune function which has been lost. Because of the many uncertainties in our current knowledge, the effect of HAART on the risk of opportunistic infections, for now, is not addressed as a factor in this revision of the Federal Guidelines on Opportunistic Infections.