DR Medhat MRCP

Viral infections
1) HIV
- HIV is a retrovirus .
- Symptomatic in 60-80% of patients and typically presents as a glandular fever type.
- Symptomatic severity is associated with poorer long term prognosis.
- It typically occurs 3-12 weeks after infection (long incubation period).
- Man returns from trip abroad with maculopapular rash and flu-like illness -
think HIV seroconversion
- For questions involving businessmen always consider STD
• Features -
1. Sore throat.
2. Malaise, myalgia, arthralgia. Flue-like illness.
3. Lymphadenopathy.
4. Maculopapular rash
5. Diarrhoea.
6. Mouth ulcers.
7. Rarely meningoencephalitis.
• Diagnosis
Antibodies to HIV : may not be present.
HIV PCR and p24 antigen tests can confirm diagnosis. (most appropriate investing.)
• HIV immunology: The following immunological changes are seen in progressive HIV:
1) Reduction in CD4 count (Th1).
2) Increase B2-Microglobulin (IBM).
3) Decrease IL-2 production (DIL=DELL) IBM & DELL
4) Polyclonal B-cell activation.
5) NK cell function.
6) Delayed hypersensitivity responses.
• Main complications of HIV : (Diarrhea ,Kaposi sarcoma , PCP,PSC,Pancreatitis)
Diarrhea in HIV :
o Causes :
1) HIV virus itself.
2) Opportunistic infection :
سؤال - Cryptosporidium protozoa : most common cause
- CMV.
- Mycobacterium avium.
- Giardia.
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