2. AIDS - Aquired Immune Deficiency Syndrome is caused by
Human Immuno deficiency Virus (HIV) which is a RNA retrovirus
MODES OF SPREAD:
sexual intercourse with infected person
use of infected hypodermic needles
transfusion of infected blood
transplacental spread to foetus from the infected mothers
Pathogenesis: HIV infects T-Cells , T-Helper cells, macrophages
and B-cells and thus interferes with mechanism of production of
immune bodies
Immunodeficiency renders individual prone to various infections
and tumors which involve multiple systems and finally cause death
3.
4. Ocular manifestations:
These occur in about 75% of patients and may be the presenting
features of AIDS in an otherwise healthy person . Ocular lesions of
AIDS may be classified as :
I. Retinal microvasculopathy
II. Usual ocular infections (Herpes zoster,H. simplex etc.)
III. Oppurtunistic infections of eye(CMV , Pneumocystis,
Candida,Cryptococcus)
IV. Unusual neoplasms
V. Neuro-opthalmic lesions
5. 1) Ocular lesions
A. ADNEXAL LESIONS a) herpes zoster opthalmicus
b) Kaposi's sarcoma of eyelid, conjunctiva
c) molluscum contagiosum of eyelid
B. ORBITAL LESIONS a) Burkitt’s lymphoma
b) orbital cellulitis
2) Anterior segment lesions
A. Dry eye
B. Conjunctival microvasculopathy
C. Infective keratitis
D. Anterior uveitis a) rifabutin induced
b) spill over from CMV retinitis
c) herpes zoster opthalmicus
6. 3) Posterior segment lesions
A. HIV retinopathy
B. CMV retinitis
C. Toxoplasmic retinitis
D. CMV optic neuritis
E. Pneumocystis carnii choroidopathy
F. Acute retinal necrosis
G. Herpes zoster retinopathy
H. Progressive outer retinal necrosis
I. Endogenous endopthalmitis
4) Neuro-opthalmic lesions
A. Cranial nerve palsies
B. Papilloedema
7. 1) Retinal microvasculopathy :
It develops from vasoocclusive process which may be either due to
direct toxic effects of virus on the vascular endothelium or immune
complex deposits in the precapillary arterioles . It is characterized
by non specific lesions :
multiple cotton wool spots occur in 50% cases
superficial and deep retinal haemorrhages occur in 15-40% cases
micro aneurysms and telangiectasia may also be seen rarely
8.
9. 2) Usual ocular infections:
These are also seen in healthy people , but occur with greater
frequency and produce more severe infections in patients with
AIDS . These include :
Herpes zoster opthalmicus
Herpes simplex infections
Toxoplasmosis chorioretinitis
Ocular tuberculosis , syphilis and fungal corneal ulcers
10. Herpes zoster opthalmicus :
It is due to reactivation of the latent infection by Varicella Zoster
virus in the dorsal root of trigeminal nerve Gasserian ganglion
It manifests with a maculo-papulo-vesicular rash which often is
preceded by pain. Usually involves upper lid DOESNOT CROSS
MIDLINE.
It has 3 clinical phases: 1) acute phase lesions
2) chronic phase lesions
3) relapsing phase lesions
TREATMENT: Oral acyclovir 800mg 5times/day or valciclovir
500mg tds , analgesics and for ocular local therapy cycloplegics for
keratitis and timolol and betaxolol for secondary glaucoma
11.
12. herpes simplex infections:
They mainly occur in two forms :
a. Primary herpes: include skin lesions ; conjunctiva-acute
follicular conjunctivitis ; cornea- fine and coarse punctate keratitis,
dendritic ulcers
b. Recurrent herpes :includes active epithelial keratitis ; stromal
keratitis ; trophic keratitis ; herpetic iridocyclitis
13. Toxoplasma retinochoroiditis:
It is an uncommon infection in AIDS. Ocular toxoplasmosis in HIV
positive patients is different in appearance from immuno
competent patients . Unlike in immunocompetent patients,HIV
infected patients have bilateral and multifocal disease associated
with anterior uveitis and viritis.
When testing patients for antibodies to toxoplasmosis both IgG and
IgM levels may be raised , but in HIV patient tests may be negative.
Often assosciated with toxoplasma lesions in Central Nervous
System
Treatment in immuno compromised patients consists of
sulphadiazine or clindamycin, pyrimethamine and folinic acid ( triple
therapy)
16. 3) Opportunistic infections of eye :
These are caused by micro-organisms which do not affect normal
patients . They can infect someone whose cellular immunity is
suppressed by HIV infection or by other causes such as leukemia.
These include:
CMV Retinitis
Candida endopthalmitis
Cryptococcal infections
Pneumocystis carnii and
Choroiditis
17. CMV Retinitis :
It is the commonest intraocular opportunistic infection seen in
patients with AIDS
Pathogenesis includes reactivation from extra ocular sites leading
to seedling in other sites such as the retina.
Patients mainly complain of minor visual symptoms such as
floaters , flashing lights or mild blurred vision or be totally
asymptomatic. It presents with wide range of clinical appearances
from cotton wool spots to confluent areas of full thickness retinal
necrosis and vasculitis. It can progress in a “brushfire” pattern
from the active edge of an active lesion .
18. Treatment in AIDS patients requires use of specific antiviral agents
ganciclovir , cidovir in conjunction with HAART. These treatments
can be administered orally ,intravenously, intravitreally.
19. Candida endophthalmitis :
Infection with Candida albicans is rare and the affected patients
usually have a history of drug abuse or indwelling central illness .
In initial stages floaters are main symptoms, as condition
progresses , whitish “puff-balls” and vitreous strands develop.
Drugs of choice include Amphotericine B and Fluconazol
20. Cryptococcal infection :
This infection mainly occurs by inhalation of airborne spores .
Organisms initially remain in the lungs then spread
hematogenously to other parts of the body . Intraocular infection
may occur via direct extension from CNS or through the blood
stream from a localized or disseminated cryptococcal infection.
Most of the infections have been seen in association with
cryptococcal septicemia with meningeal infection .
21.
22. Pneumocystis carnii:
Pneumocystis choroiditis was common in earlier years of HIV
pandemic but use of systemic antimicrobials such as trimethoprim –
sulfamethoxazole eradicated this ocular manifestations. Deep
orange lesions are characteristic of P.carnii choroiditis. They
generally do not affect vision and fade with antimicrobial treatment
23. 4) Unusual neoplasms :
Kaposi's sarcoma:
It is a malignant vascular neoplasm which may appear on eyelid or
conjunctiva as multiple violaceous non tender nodules. It is the
commonest anterior segment lesion seen in AIDS. Typically it
involves only skin but when there is reduced CD4 count it
progresses to other sites
24. Burkitts lymphoma :
Burkitt’s lymphoma of the orbit is seen in only few
patients.
25. 5) Neuro-opthalmic lesions:
These are thought to be due to CMV or other infections of the
brain. These include :
Cranial nerve palsies isolated or multiple resulting in paralysis
of eyelids,extraocular muscles,
Loss of sensory supply to the eye,
Optic nerve involvement causing loss of vision
27. Management:
It consists of measures directed against associated
infection / lesions like :
CMV infections can be treated by zidovudine,
ganciclovir and foscarnet
Kaposi's sarcoma responds well to radiotherapy
Herpes zoster opthalmicus is treated by acyclovir
