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1st August 2023
Opportunistic Infections
The immunocompromised state of many HIV patients means they are vulnerable to various opportunistic infections. These are AIDS-defining illnesses, and many are listed in Table 2 above.
A useful way to consider these infections is the risk in relation to CD4 count, which is summarised in the following table.
| CD4 count | Associated conditions at risk of |
|---|---|
| <50 | Mycobacterium avium complex Cytomegalovirus (and cytomegalovirus retinitis) |
| 50-100 | Cryptococcal meningitis Oesophageal candidiasis Aspergillus |
| 100-200 | Toxoplasmosis Cryptosporidiosis Histoplasmosis PCP JC virus |
| 200-500 | Varicella zoster HHV-8 (i.e. Kaposi’s) Oral candidiasis Oral hairy leukoplakia (due to Epstein-Barr virus) Tuberculosis |
| More than 500 | Little risk of opportunistic infections |
Table 3: CD4 count with associated conditions
The key opportunistic infections are covered in greater detail in the Common Infections in Immunocompromised Hosts section.
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