A Guide to Primary Care of People with HIV/AIDS - Canadian Public ...

A Guide to Primary Care of People with HIV/AIDS
Chapter 9: Management of Opportunistic Diseases
Chapter 9:
Management of Opportunistic Diseases
Constance A. Benson, MD
OVERVIEW
PNEUMOCYSTIS JIROVECI (CARINII) PNEUMONIA (PCP)
MYCOBACTERIUM AVIUM COMPLEX (MAC)
CYTOMEGALOVIRUS INFECTION (CMV)
CANDIDA ESOPHAGITIS
CENTRAL NERVOUS SYSTEM DISEASES
MYCOBACTERIUM TUBERCULOSIS
MALIGNANCIES
KEY POINTS
SUGGESTED RESOURCES
OVERVIEW
What are the major opportunistic diseases
(ODs) in patients with HIV/AIDS?
The diseases that occur as a result of HIV-related
immunodeficiency include both opportunistic infections
(OIs) and malignancies. The risk of developing an OI
has declined dramatically with the widespread use of
potent combination antiretroviral therapy (ART) (see
Figure 9-1). The major OIs that occur in patients with
HIV are Pneumocystis carinii pneumonia (the organism
that causes human disease in PCP is now classified as
Pneumocystis jiroveci, but PCP remains the conventional
abbreviation in clinical use), tuberculosis, disseminated
Mycobacterium avium complex (MAC) disease,
cytomegalovirus (CMV) disease, Candida esophagitis,
central nervous system (CNS) infections such as
cryptococcal meningitis or Toxoplasma encephalitis,
and cryptosporidiosis. While Mycobacterium tuberculosis
is an infection that occurs in both immunocompetent
and immunosuppressed patients, it remains one of the
most common opportunistic co-infections in persons
with HIV disease and is responsible for considerable
morbidity and mortality worldwide. A host of other
OIs may be seen less commonly or in patients in
geographic areas where specific infections are endemic,
eg, histoplasmosis in the central Midwest part of the
U.S. or isosporiasis in
South Florida and Puerto
Rico.
See Pocket
Guide Adult OI
Tables 1–6
What factors are
associated with higher
risk of developing an OI?
OIs occur primarily in HIV-infected individuals who
are not receiving either OI prophylaxis or ART (or who
have not responded to it with an increase in their CD4
cell counts above the threshold that predicts risk of
developing an OI). The principal risk of
Table 9-1. Risk Factors Associated with
Development of Major Opportunistic
Infections in HIV-Infected Individuals
Opportunistic
Infection
Pneumocystis carinii
pneumonia
Mycobacterium
tuberculosis
Mycobacterium
avium complex
Cytomegalovirus
disease
CD4 Count
Risk
Threshold
(cells/mm 3 )
≤200
Any
≤50
≤50
Other Risk Factors
Prior PCP
Percent CD4 cells 10 5
copies/mL)
Seropositive (IgG antibody
to CMV)
CMV viremia
Prior OD
High viral load
(>10 5 copies/mL)
Cryptococcal
≤50-100 Environmental exposure
meningitis
Toxoplasmosis ≤100-200 Seropositive (IgG antibody
to T. gondii)
Candida esophagitis ≤100 Prior Candida colonization
High viral load
(>10 5 copies/mL)
Cryptosporidiosis ≤100 Environmental exposure
(contaminated water, soil,
animal exposure)
Histoplasmosis ≤100 Exposure (endemic areas
– Midwest, Southeast U.S.)
Coccidioidomycosis ≤100 Exposure (endemic areas
– Southwest U.S., Mexico)
9
U.S. Department of Health and Human Services, Health Resources and Services Administration, HIV/AIDS Bureau
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