HIV/AIDS and the Eye

HIV/AIDS Overview:

• HIV/AIDS is a disease of the human immune system
• Causes gradual decrease in CD4+ T lymphocytes with subsequent opportunistic infections and neoplasia.
• Ocular involvement in 70-75% of patients
• HIV-1 & HIV-2
• Lentivirus subfamily of retrovirus
• HIV-1 Most common
• HIV-2 commoner in West Africa

CD4 Count and Ocular Manifestation:

• 1000 cells/mm3 - Normal
• <500 - Kaposi sarcoma, lymphoma, T.B.
• <250 - Toxoplasma, Pneumocystis carinii
• <100 - CMV Retinitis, VZ Retinitis, HIV retinopathy, sicca syndrome

Ocular Manifestations of HIV/AIDS:

• ADNEXAL MANIFESTATIONS
• ANTERIOR SEGMENT MANIFESTATION
• POSTERIOR SEGMENT MANIFESTATIONS
• NEURO-OPHTHALMIC MANIFESTATIONS
• ORBITAL MANIFESTATIONS
• DRUG-RELATED OCULAR TOXICITY IN HIV INFECTED PATIENTS

Specific Tissue Involvement:

• Anterior Segment- lids, conjunctiva, the lacrimal drainage system, cornea
• Posterior Segment- Retina, choroid, and optic nerve

• Herpes Zoster Ophthalmicus (HZO)
• Kaposi Sarcoma
• Molluscum Contagiosum
• Conjunctival Microvasculopathy (Conjunctival Microvasculopathy)
• 70 - 80% of HIV Patients
• Aetiology:
• - Increased Plasma Viscosity
• - Immune-Complex Deposition
• - Direct Infection of the Conjunctival Vascular Endothelium by HIV
• These changes include segmental vascular dilation and narrowing, microaneurysm formation, comma-shaped vascular fragments.

• Herpes Zoster Ophthalmicus
• Kaposi Sarcoma
• Molluscum Contagiosum
• Keratoconjunctivitis Sicca
• Conjunctival Squamous Cell Carcinoma
• Infectious Keratitis:
• Viral: Varicella Zoster Virus, HSV I & II
• Fungal: Fusarium solani, Aspergillus
• Protozoal: Microsporidia
• Iridocyclitis: CMV, Varicella Zoster Virus, HSV, or Endogenous autoimmune uveitis like Reiter’s syndrome

Molluscum Contagiosum

General Information:

• 20% of patients
• Highly contagious dermatitis caused by DNA poxvirus
• May affect mucous membranes as well as skin.

Treatment: Excision, cryotherapy, topical agents- phenol and trichloroacetic acid.

Manifestations:

• Adnexal
• Conjunctival

Keratoconjunctivitis Sicca

Clinical Features:

• Destruction of lacrimal glands
• Burning uncomfortable red eyes

Treatment: Artificial tear drops, lubricating ointment

Herpes Zoster Ophthalmicus

Clinical Features:

• Herpes Zoster virus
• Reactivation
• Dermatomal pain, Rash

Ocular Manifestations:

• Keratitis
• Conjunctivitis, episcleritis, scleritis, uveitis, glaucoma, pthisis bulbi

Treatment: Acyclovir 3% eye ointment 5 times/day, Tab Acyclovir 800mg 5 times/day

Anterior Uveitis

• Herpes simplex
• Herpes Zoster
• CMV
• Toxoplasmosis
• Syphilis
• Drug induced - Rifabutin

Kaposi Sarcoma

Clinical Features:

• Vascular neoplasm
• Commonest anterior segment lesion
• Affects the eyelids (purple nodules), or conjunctiva – red mass

Treatment:

• Radiation therapy
• Intralesional chemotherapy
• Surgical excision

Conjunctival Squamous Cell Carcinoma

Clinical Features:

• Pink gelatinous growth on the bulbar conjunctiva
• Interaction between HIV, sunlight, HPV
• Feeding blood vessel

Treatment:

• Excision & cryotherapy
• Exenteration – if orbit involved

• HIV Retinopathy
• HIV-Linked Retinochoroiditis
• Cytomegalovirus Retinitis

HIV Retinopathy

Common Features:

• Commonest retinal pathology in HIV
• Characteristic cotton wool spots

Cause:

• Due to microangiopathy induced by plasma hyperviscosity, immune complex deposition, or direct viral endothelial attachment

HIV-Linked Retinochoroiditis

Viral:

• Varicella Zoster - Progressive Outer Retinal Necrosis (PORN)
• Herpes Simplex - Anterior Retinal Necrosis (ARN)

Bacterial:

• Treponema Pallidum (Syphilis)
• Mycobacterium Tuberculosis

Fungal:

• Cryptococcus Neoformans
• Histoplasma Capsulatum
• Candida
• Aspergillus

Parasitic:

• Toxoplasma Gondii
• Pneumocystis

Cytomegalovirus Retinitis

Overview:

• Most common intraocular infection in HIV
• Transmitted by close contact in children, by sexual contact, and blood transfusion in adolescence and adults
• Primary infection is asymptomatic
• Secondary reactivated infection is life and vision-threatening

Symptoms:

• Floaters
• Decreased vision
• Flashes or asymptomatic

Clinical Signs:

• Tomato ketchup appearance
• Progress in brushfield pattern
• Retinal detachment may occur

CMV Retinitis

Treatment:

• IV Gancyclovir initially, then oral
• Intravitreal injections – 200 - 2000ug/0.1 ml
• Bone marrow suppression may occur

Alternative Treatments:

• IV Foscarnet – for gancyclovir-resistant cases, also administered intravitreally
• Valgancyclovir:
  • Induction – 900mg BD
  • Maintenance – 900mg OD
• Cidofovir – 5mg/kg IV once weekly for 2 weeks + probenecid

ACUTE RETINAL NECROSIS

Causative Agent: Herpes Zoster infection

Clinical Features:

• Vitritis
• Macular edema
• Peripheral whitening retinal lesions

Treatment:

• Acyclovir IV for 14 days
• Followed by oral acyclovir 5 times daily for 6-12 weeks

PROGRESSIVE OUTER RETINAL NECROSIS (PORN)

Causative Agent: Varicella Zoster virus

Clinical Features:

• White lesions in mid & peripheral retina
• Rapid loss of vision

Treatment:

• IV gancyclovir or Foscarnet
• Intravitreal foscarnet

Prognosis: Poor

TOXOPLASMA CHORIORETINITIS

Causative Agent: Protozoan disease - Toxoplasma gondii

Associated Conditions: Also causes encephalitis

Clinical Features:

• Floaters, flashes, reduced vision
• Headlight in the fog appearance

Treatment: Steroids, clindamycin, sulphadiazine

SYPHILIS

Clinical Manifestations:

• Uveitis
• Retinitis
• Optic neuritis
• Papillodema

Treatment: High dose iv penicillin

FUNGAL INFECTION

Candida & Cryptococcus:

• Snowball-like lesions
• Neuropathy

Treatment: Amphotericin B + Fluconazole

TUBERCULOSIS

Ocular Manifestations:

• The most common ocular manifestation is anterior uveitis and choroiditis.
• Manifests as areas of necrosis surrounded by mononuclear and giant cells.
• Unifocal/multifocal yellowish or whitish choroiditis.

Prevalence: 10-15% of patients

Common Causes: Meningitis, Meningeal Lymphoma, Neurosyphilis, Toxoplasmosis.

Neuro-ophthalmic Manifestations:

• Papilledema due to increased intracranial pressure
• Optic neuritis
• Cranial nerve palsies
• Ocular motility disorders
• Visual field defects

Treatment:

• Antibiotic Rx for infectious causes
• Systemic steroids in severe cases of optic neuritis
• Radiation and chemotherapy for lymphoma

Common Complications:

• Orbital lymphoma
• Orbital cellulitis (Aspergillus infection)
• Orbital Kaposi sarcoma

Treatment:

• Lymphomas - treated with radiation and chemotherapy
• Orbital cellulitis - systemic antibiotics

Antiretroviral Drug-Related Toxicity

Rifabutin: Intraocular inflammation (uveitis) - 33%

Cidofovir: Uveitis and intraocular hypotony - 25-30%

Didanosine: Retinal pigment epithelial abnormalities

Long-term Atovaquone: Corneal subepithelial deposits

The drug toxicities are dose-related and resolve with discontinuation of the drug.