Henry Masur, from the National Institutes of Health,
Bethesda, Maryland, discussed the changing nature of
opportunistic infections (OIs) in HIV-infected persons in the
United States in light of the use of highly active antiretroviral
therapy (HAART). While the incidence of nearly all OIs has
decreased since 1996, several AIDS-related malignancies
have maintained stable incidence rates and will likely
assume greater importance. Complications resulting from
infection with hepatitis C virus (HCV) will become more
prevalent, since as many as 30% of HIV-infected persons are
coinfected with HCV. Several “reconstitution syndromes,”
illnesses attributed to improved T-cell immunity, have been
described as unusual manifestations of OI in the first few
weeks following initiation of HAART. Antimicrobial
resistance is an increasing problem for bacterial and fungal
OIs and threatens to diminish the efficacy of trimethoprimsulfamethoxazole
against Pneumocystis carinii pneumonia,
although evidence of this effect is incomplete at present. OIs
also occur because many persons remain undiagnosed with
HIV and therefore do not receive appropriate prophylaxis
against OIs. The fact that only a minority of persons receiving
HAART maintain undetectable virus levels for a sustained
period suggests that HAART will not be effective in many of
these patients and that OIs will increase in incidence.