Perspective: Information, Inspiration and Advocacy for People Living with HIV/AIDS

PHS Guidelines on Opportunistic Infections
The US Public Health Service (PHS) recently issued new guidelines for the prevention (prophylaxis) and maintenance (to prevent recurrence) of opportunistic infections (Ols). 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 01 reoccur. However,
many researchers believe that the specific types of CD4+ cells, which
provide protection against specific Ols, may be lost due to immune
Pnaeumocystis
carinii Pneumonia
Prevention: The guidelines for preventing PCP remain unchanged. People with 200 CD4+ cells or less, people with
unexplained fevers (greater than 100'F for 2 weeks) or a
history of candidiasis in the throat (i.e. thrush) should
start PCP preventative therapy. TMP/SMX (Bactrim or
Septra) remains the drug of choice. However, the recommendations suggest that either one double-strength tablet
or one single-strength tablet per day are equally effective
and the lower dose may be better tolerated (see "Update
on Opportunistic Infections" on page 16). Additionally,
TMP/SMX may also be able to prevent other HIV-related
infections such as toxoplasmosis and many bacterial infections. If TMP/SMX cannot be tolerated, dapsone, dapsone + pyrimethamine + leucovorin or aerosolized pentamidine can be used. Dapsone + pyrimethamine should also
provide protection against toxoplasmosis, but not against
bacterial infections.
Maintenance: To prevent recurrence of PCP, the guidelines recommend the same options as those for prevention.
Prevention in Children: Children who are born to HIVinfected mothers should start receiving PCP preventative
therapy with TMP/SMX beginning at 4-6 weeks of age. If
the child is subsequently found not to be HIV-infected,
then the therapy should be stopped. However, if the child
is found to be HIV infected, then the therapy should be
continued for at least a year. Subsequent decisions on starting PCP prevention therapy should be based on CD4+ cell
counts.
Prevention During Pregnancy: Pregnant women with
200 CD4+ cells or less should also start PCP preventative
medication with a double strength tablet of TMP/SMX
after the first trimester of pregnancy. However, if PCP prevention is felt to be necessary during the first trimester of
pregnancy, aerosolized pentamidine should be considered
as first option as TMP/SMX may harm the developing fetus.

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.
Tcoplasmosis
Prevention: People should be tested for antibodies against
toxoplasma after diagnosis of HIV infection. People who
do not have antibodies against toxoplasma should take
precautions to avoid infection by the organism. These
precautions include: cooking meat so that the inside reaches
at least 150'F; washing hands after handling raw meat,
gardening, changing diapers, or litter boxes; and, for cat
owners, keeping the cat indoors and not feeding it raw or
undercooked foods.
People who have antibodies for toxoplasma should start
preventative medication with TMP/SMX (Bactrim or
Septra) if their CD4+ cell counts fall below 100. For people
who cannot tolerate this drug, dapsone + pyrimethamine
is recommended. Fortunately, most people with CD4+
counts below 100 are already using TMP/SMX for prevention of PCP. Therefore, no additional drug needs to be
taken if they tolerate TMP/SMX well.
Maintenance: To prevent the recurrence of toxoplasmosis, the combination of pyrimethamine + sulfadiazine +
leucovorin is recommended. For people who cannot tolerate sulfa-based drugs, pyrimethamine + clindamycin may
be an alternative.
Prevention in Children: The guidelines for preventing
toxoplasmosis in children are similar to those for PCP,
with some minor differences. Children who are antibody
positive for toxoplasma and cannot tolerate TMP/SMX
should receive dapsone + pyrimethamine.
Prevention During Pregnancy: The guidelines for prevention of toxoplasmosis for pregnant women are also
similar to those for preventing PCP. However, it is recommended that pregnant women defer taking pyrimethamine
until after the pregnancy because of the low incidence of
toxoplasmosis in the United States and because of potential harm to the developing fetus.

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PI PERSPECTIVE NUIVBER 23 NOVEIVBER 1 997