Advanced HIV, AIDS, and HIV-Associated Conditions
Article status: Temporary high-yield summary
- This article will be fully reviewed, expanded, and referenced in due course
- Current content focuses on core principles and exam-relevant concepts
Key learning points of this article for exams:
- Learn the definition of AIDS and advanced HIV disease
- Recognising key AIDS-defining conditions vs non-AIDS-defining opportunistic infections
- Learn further information on several important AIDS-defining conditions (detailed and labelled below)
Definition
Both AIDS and advanced HIV disease are used to refer to advanced stages of HIV infection.
- Advanced HIV disease: CD4 count <200 cells/mm3 OR WHO stage 3 / 4 illness
- AIDS: CD4 count <200 cells/mm3 OR presence of AIDS-defining condition
Note that WHO stage 4 illness = AIDS-defining conditions.
WHO Stage 3 Illnesses
| Condition / illness | Description / notes |
|---|---|
| Unexplained severe weight loss | Persistent weight loss of >10% body weight |
| Unexplained persistent fever |
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| Oral hairy leukoplakia |
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| Persistant oral candidiasis | In contrast to oral hairy leukoplakia, oral candida causes white patches that CAN be scraped off
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| Severe bacterial infections |
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| Unexplained blood count abnormalities |
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| Unexplained chronic diarrhoea | >1 month |
| Pulmonary tuberculosis | TB confined to the lungs, NOT extra-pulmonary |
| Active necrotising ulcerative stomatitis | Gingivitis or periodontitis |
WHO Stage 4 Illness (AIDS-Defining Conditions)
The following ones are more likely to be tested in exams, therefore are presented separately.
| Condition | Cause | Clinical features | Investigation | Management* |
|---|---|---|---|---|
| Kaposi sarcoma | Soft-tissue cancer caused by HHV-8 |
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Mainstay is ART |
| Pneumocystis pneumonia (PCP) – most common AIDS-defining condition | Fungs: Pneumocystis jirovecii |
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Primary prevention: start co-trimoxazole when CD4 <200
Management:
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| Oesophageal candidiasis | Candida albicans |
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1st line: oral fluconazole |
| CMV infection | CMV (HHV-5) |
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| Chronic cryptosporidiosis | Intracellular intestinal parasite: Cryptosporidium parvus |
Note cryptosporidosis is self-limiting in immunocompetent people but chronic in HIV |
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| CNS toxoplasmosis | Intracellular parasite: Toxoplasma gondii | Subacute onset:
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| Primary cerebral lymphoma | EBV-driven B-cell non-Hodgkin lymphoma | Subacute onset (may mimic toxoplasmosis):
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| Progressive multifocal leukoencephalopathy | JC virus reactivation |
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| Cryptococcal meningitis | Yeast: Cryptococcus neoformans | Subacute presentation:
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*Assumes underlying HIV is being treated with ART – see the Human Immunodeficiency Virus (HIV) article for more information.
The remaining ones:
| HIV wasting syndrome |
| Chronic herpes simplex |
| HIV encephalopathy |
| Disseminated mycosis |
| Recurrent septicaemia |
| Invasive cervical carcinoma |
| Extra-pulmonary cryptococcosis |
| Non-Hodgkin B cell lymphoma |
| Recurrent severe bacterial pneumonia |
| Extra-pulmonary tuberculosis |
| Disseminated non-tuberculous mycobacteria (e.g. Mycobacteria avium complex) |
| Chronic isospsoriasis |
| HIV-associated nephropathy / cardiomyopathy |
Opportunistic Infections
Note that opportunistic infections can be AIDS-defining or non-AIDS-defining.
Key infections that are NOT AIDS-defining:
- Oral candidiasis (thrush)
- Pulmonary TB (see the Tuberculosis (TB) article)
- Shingles (herpes zoster) (see the Shingles article)
- Oral hairy leukoplakia (EBV)
- Seborrhoeic dermatitis (see the Seborrhoeic Dermatitis article)
See the WHO stage 4 illness (AIDS-Defining Conditions) section above for opportunistic infections that are AIDS-defining.
HIV-Associated Complications
Key HIV-associated complications that are NOT covered in the sections above:
| Constitutional symptoms |
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| Neurological |
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| Cardiovascular |
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| Metabolic |
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| GI |
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| Renal |
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| Hepatic |
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