HIV Flashcards
(34 cards)
What are the 3 major structural genes of HIV?
Gag, Pol, Env
What does gag encode?
nuclear proteins
What does pol encode?
viral enzymes: reverse transcriptase, intergrase, protease
What other genes make up the structure of HIV?
Rev, tat and nef
What does env encode?
envelope glycoproteins?
Name the fungal infections that commonly cause fungal disease in HIV?
Candida albicans
Cryptococcus neoformans (CN)
Cryptococcal meningitis
Pneumocystis Jiroveci (PCP)
What is the most common feature of candida albicans in HIV infection, and how else can it occur?
Oral thrush = most common opportunistic infection
Oesophageal candidiasis = AIDs defining
Candida septicaemia = rare (IVDU and Neutropaenic conditions)
What are the signs and symptoms of oral thrush?
Creamy white plaques can be stripped off from surface of tissue (unlike OHL), Erythematous patches, Angular chelitis
Asymptomatic.
Tongue perversion, oral discomfort, pharyngeal discomfort on swallowing
What are the symptoms of oesophageal candidiasis?
- Nausea & Dysphagia
- Retrosternal pain on swallowing (odynophagia)
- Creamy white plaques
How is candida albicans diagnosed?
- Clinically
- Trial of therapy
- Endoscopy (if no response to therapy)
What is the treatment for candida albicans?
- Topical Nystatin/ Amphotericin lozenges
- Fluconazole 50-100mg/d
- If resistant: long term use of F or CD4<50: Itraconazole, IV amphotericin
How does CN occur?
High incidence in Africa
• Inhaled from bird faeces
• Sites: skin, lungs, meninges, brain
What are the signs and symptoms of CN, and how is it diagnosed?
Skin = umbilical papules & ulceration (like MC)
Lungs (40% CN):
Cough, SOB, fever
CXR = consolidation +/- cavitation, interstitial infiltrates, effusions
Dx = Broncho alveolar lavage
How does CM occur?
Cryptococcal meningitis
50-85% with CN
Life threatening
CD4 <50
What are the signs and symptoms of CM?
Headache (most common), Fever, Mental change
Signs:
may be absent, meningeal irritation, Neuro signs (uncommon)
How is cryptococcal meningitis diagnosed?
Serum CRAG (cryptococcal Ag) CSF: Indian ink stain (cryptococci), CRAG
Culture +/- lymphocytes
low glucose, high protein, high ICP
What is the treatment for CM?
Treat for 6 WEEKS MIN or until CSF FREE:
- IV AMPHOTERICIN +/- FLUCOCYSTEINE if severe
- Then oral fluconazole
- Repeat LP to confirm sterilisation
Prophylaxis: fluconazole
Manage = intracranial hypertension
How does PCP occur in HIV?
CD4 < 200
Less common since 1ary prophylaxis
What are the S + S of PCP?
- Dyspnea on exertion
- Non protective cough
- Fever, weight loss
- diarrhoea
Signs
• Pyrexia
• Chest signs
• O2 desat on exertion
How is PCP diagnosed?
CXR: Bilateral infiltrates (bat wings), Atypical appearance (effusions, cavitations, consolidation), Upper lobes only (pentamidine nebs prophylaxis)
ABG
O2 desaturation on exercise
BAL: SILVER STAINING, IMF, PCR
How is PCP treated?
- CO-TRIMOXAZOLE 120mg/kg in 3 divided doses/d
- IV PENTAMIDINE
- Clincamycin & Primaquine
In severe PCP pO2 <10kPa: (steroids)
• Iv methylprednisolone
• Oral prednisolone
Prophylaxis = co-trimoxazole, pemtamidine nebuliser, Dapsone
List the common protozoal infections in HIV?
Toxoplasmosis gondii (TG) Cryptosporidium parvum Microsporidiosis Isoporiadiasis Aspergillus fumigatus HIstoplasmosis Peniclliosis Coccidioidomycosis
What are the clinical features of Toxoplasmosis gondii?
- Cat faeces
- CD4 <200
- Common in Europe, france 80% IgG anti-Tg positive
3 F’s:
- Fever
- Focal neurological signs: CN palsies
- Fits
Headache, Confusion, eventually coma
Dx: IgM not helpful and Negative IgG does not exclude TG (only in countries of low prevalence in anti-TG Abs)
What is the treatment for TG?
Sulphadiazine + Pyramethamine (or Dapsone or Clindamycin)
6 weeks of treatment
Prophylaxis: Dapsone + Pyramethamine
