HIV and opportunistic ocular infections Flashcards
What is HIV?
HIV (human immunodeficiency virus) is a virus that damages the cells in your immune system and weakens your ability to fight everyday infections and disease.
AIDS (acquired immune deficiency syndrome) is the name used to describe a number of potentially life-threatening infections and illnesses that happen when your immune system has been severely damaged by the HIV virus.
While AIDS cannot be transmitted from 1 person to another, the HIV virus can.
There’s currently no cure for HIV, but there are very effective drug treatments that enable most people with the virus to live a long and healthy life.
What is the different categories of HIV?
Stage 1 – Clinical Latency /
Asymptomatic
Stage 2 – Mild HIV Signs and
Symptoms
Stage 3 – Advanced HIV Signs & Symptoms
Stage 4 – Acquired Immune Deficiency Syndrome (AIDS)
What is involved in stage 1 of HIV?
Immune system produces antibodies. Inhibits virus spike but cannot eliminate
Viral set point established
8-10 years duration (set point / HIV subtype)
CD4+ (T-helper) cell count > 500 cell / ml
What is involved in stage 2 HIV?
Minor signs and symptoms of HIV appear: Candidiasis, Lymphadenopathy, Molluscom contagiosum, Persistent hepatosplenomegaly, Poly pruritic eruptions, Herpes zoster.
Allergic conjunctivitis
Keratoconjunctivitis sicca
Cotton wool spots (early reliable sign)
Microvascular changes
Microaneurysm
Dot & blot haems
Telangiectasia
Capillary dropout
What is involved in stage 3 HIV?
Appear of wasting / losing weight
Life-threatening opportunistic infections develop:
Cryptosporidiosis
Peripheral & lymph node tuberculosis
Persistent fever (>1 month)
Persistent candidiasis
Recurrent bacterial pneumoniaNecrotizing Herpetic Retinitis
Posterior segment inflammation by varicella zoster
Acute retinal necrosis (ARN)
Single of multiple area of retinal necrosis with distinct borders
White-yellow patches of necrotizing retinitis usually first appear in the far- or mid-periphery
Extension of foci of retinal necrosis in a circumferential fashion
Patches become larger, increase in number and coalesce
Posterior pole spared till late in disease course
Prominent anterior chamber and vitreous inflammation
Anterior granulomatous or non-grnaulomatous uveitis
Keratic precipatates
Severe vitritis
Retinal arteritis
What is involved in stage 4 HIV?
Viral load increases.Life-threatening opportunistic infections develop
Pneumocystis jirovecii pneumoinia
Cytomegalovirus infection
Toxoplasmosis
Mycobacterim avium
Cryptococcal meningitis
Kaposi sarcoma
Death at any moment - AIDS
Kaposi’ sarcoma: Vascular tumour presenting as purple/red nodules on skin and mucous membranes
What is CMV retinitis?
Cytomegalovirus (CMV) part of Herpesviridae family. Remains latent within body for long periods. Associated with mucous membranes
50 – 80 % of adults carry CMV. Infection usually occurs without symptoms. May give nonspecific viral symptoms. Once infected carries CMV for life, usually not symptoms. Most common AIDS-related ocular opportunistic infection. May be unilateral by 52% develop bilateral disease. CMV infects the retina. Inflammation depends on immune status of host.
What are the 3 forms of CMV retinitis?
- Fulminant form (Fulminant: suddenly with great severity)
- Indolent Form (Indolent: causing little or no
pain) - Florid Form (excessively intricate or elaborate)
What is the Fulminant form?
Fulminant form (Fulminant: suddenly with great severity)
Pizza pie retinopathy / cottage cheese with ketchup
Confluent retinal necrosis with haems
Advancing edge of lesions very sharp
Spreads contiguously (sharing edge)
Behind the spreading border of haems and
exudate is necrotic retina
Full-thickness retinal opacification
What is the Indolent form?
Indolent Form (Indolent: causing little or no
pain)
Granular lesion in the peripheral retina
Little or no haemorrhage
Characteristic small white ‘satellite’ lesions
just outside border of confluent necrotizing
retinitis
DDx CMV retinitis from herpetic retinitis or
toxoplasmosis
15% of patients asymptomatic
What is the Florid form?
Florid Form (excessively intricate or elaborate)
Frosted branch/ brush fire angitis
Severe vascular sheathing and retinal edema
Viral antigens form immune-complexes and deposit in
retinal vessels causing vasculitis.
Viral invasion of endothelial cells by CMV
What is progressive outer retinal necrosis?
Develops when severely immune depressed - AIDS
Severe end of spectrum of herpetic retinitis
Rapid necrotizing retinitis - rapidly involves the macula as well as peripheral
retina
Multifocal lesions with deep retinal opacification
Retinal lesion in the macula become confluent to form a cherry red spot (not to
be confused with cherry red spot in CRAO)
‘cracked mud’ appearance
No vasculitis
Minimal intraocular
inflammation (as
immune system is absent!
What is the treatment for CMV retinitis?
Ganciclovir
Foscarnet
Cidofovir
Valganciclovir
Fomivirsen
What is toxoplasmosis?
AIDS: Toxoplasma gondii is primary infection rather than
reactivation
Bilateral / Multifocal
Not associated with chorioretinal scars
Signs & Symptoms
* Iritis
* Vitritis
* Choroiditis
* Multifocal or diffuse necrotizing retinitis
* DDX from CMV retinitis
Intraocular inflammation more severe
Fewer haemorrhages
Treat with antiparasitic drugs
What is the treatment for HIV?
HIV treatment does not cure HIV, but it stops the virus from reproducing in the body. It can reduce the amount of virus in the blood to undetectable levels, meaning that it cannot pass on HIV.
2 x Nucleoside Reverse transcriptase inhibitors
1 x Protease inhibitor OR Non-nucleoside reverse transcriptase inhibitors OR Integrase inhibitor
Inhibit progression of AIDS
