HIV/AIDS Flashcards
What are the different types of HIV?
HIV 1 - Most common
HIV 2 - Less common in the UK. It is slower to progress and harder to transmit.
What are the methods of transmission of HIV?
- Anal or vaginal intercourse (oral route not)
- Injecting drugs/sharing equipment
- Mother to child trasmission,
- Transmission in healthcare settings
- Donated blood/clotting factors
Explain the pathophysiology of HIV
The virus infects cells which carry CD4 t helper cells.
It is a retrovirus so uses host cell machinery to undergo reverse transcription and then inserts its DNA into host DNA.
Then causes depletion of CD4 cells.
Virus can lay dormant in CD4 cells for a long period of time. Person then undergoes seroconversion
What is primary HIV infection?
The first 6 months following HIV infection
What are the symptoms of HIV seroconversion?
Usually occurs within 3 weeks of infection but can occur later. Presents with a glandular fever type illness
- Sore throat,
- Lymphadenopathy,
- Malaise, myalgia, arthralgia,
- Diarrhoea,
- Maculopapular rash,
- Mouth ulcers
- Rarely: meningioencephalitis
What are the HIV indicator conditions?
- STIs,
- Malignant lymphoma,
- Anal cancer,
- Cervical dysplasia
- Herpes zoster/shingles,
- Hepatitis B or C,
- Glandular fever,
- Community acquired pneumonia,
- Unexplained leukocytopenia/thrombocytopenia,
- Peripheral neuropathy,
- Mononeuritis,
- Unexplained weight loss,
- Unexplained fever,
- Unexplained diarrhoea,
- Guillian barre syndrome
What are some AIDs defining illnesses
Pneumocystis pneumonia,
Oral hairy leucoplakia,
Oesophageal candida,
TB,
Kaposi’s Sarcoma,
Chronic diarrhoea,
Bacterial pneumonia,
Dementia,
Mycobacterium avium complex (MAC)
Neurological complications - Toxoplasmosis and lymphoma
What opportunistic infections occurs with a CD4 count of 200-500 cells/mm3
- Oral thrush,
- Shingles,
- Hairy leukoplakia,
- Kaposi sarcoma
What opportunistic infections occurs with a CD4 count of 100-200
Cryptosporidiosis,
Cerebral toxoplasmosis,
Progressive multifocal leukoencephalopathy (due to JC virus)
Pneumocystis jirovecii pneumonia
HIV dementia
What opportunistic infections occurs with a CD4 count of 50-100
Aspergillosis,
Oesophageal candida,
Cryptococcal meningitis
Primary CNS lymphoma,
What opportunistic infections occurs with a CD4 count of < 50
CMV retinitis
Mycobacterium avium-intracellulare infection
What is the presentation of MAC?
It causes chronic lung disease (nodular bronchiectasis) and can become disseminated, affecting other organs and causing lymphadenitis.
Symptom are: fever, sweats, abdominal pain, diarrhoea, hepatomegaly and deranged LFTs.
Diagnosis: Blood cultures and bone marrow exam
Treat: Rifabutin, ethambutol and clarithromycin.
What are the investigations for HIV
- HIV antibody (ELISAs) however has to be done 3 months after exposure
- HIV antibody and antigen. Look for p24 antigen
- Bloods: HIV viral load, FBC, lymphocyte subset pannel (look at CD4 count), U&Es, LFTs
- Screen for viral hepatitis
What is the most common cause of diarrhoea in a patient with HIV?
Cryptosporisium - intracellular protazoa. Investigate via Ziehl-Neelsen stain of stool.
Other causes may be: CMV, MAC, Giardia
What is the management of HIV?
Antiretrovial therapy (ARTs) which consists of two nucleoside reverse transcriptase inhibitors (NRTI) and either a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor.
