Retinal Disorders III

Question 1

Toxoplasmosis

Answer 1

Obligate intracellular protozoan parasite

• toxoplasma Gondi
• definitive host: cat

Question 2

Neuro sequelae of toxoplasmosis

Answer 2

Targets neuro and muscular tissue

• ADD, seizures, Parkinson’s, Tourette’s
• bipolar disorder, schizophrenia

Question 3

Congenital vs acquired transmission of toxoplasmosis

Answer 3

• pregnant mother without immunity
• hand to mouth, wound or mucous membrane penetration
• gardening, walking barefoot
• ingestion of unpaseurized milk, undercooked meat

Question 4

Ocular findings of toxoplasmosis (Activated)

Answer 4

Focal necrotizing retinitis 
Satellite lesions 
Spill over into anterior chamber
Headlight in fog (severe vitritis)
Massive granuloma 
Juxtapapillary retinochoroiditis

Question 5

Toxocariasis

Answer 5

Affects younger individuals exposed to dog and cat feces

• helminthic infection by roundworm of dog (toxocara canis) or cat (toxocara Cati)
• soil, feces, puppy saliva, puppy feces
• most often due to the dog round worm

Question 6

Ocular findings of toxocariasis

Answer 6

Leukocoria
Vitritis 
RD
Macular granuloma 
Peripheral granuloma 
Chronic endoppthalmitis

Question 7

Presumed ocular histoplasmosis (POHS)

Answer 7

Mycoses in humans

• primary infection is in the lungs
• 90% infections are benign and asymptomatic
• 10% infections are symptomatic
• droppings from chickens or bats

Question 8

Ocular findings in presumed ocular histoplasmosis

Answer 8

Histo spots
-round to oval shaped
-sharp, demarcated 
-yellow white scars, may have pigment
-multiple: 1/8 DD-1/2DD size
-bilateral
-posterior pole and equator 
Peripapillary atrophy
Exudative maculopathy (4.5% in all POHS)

Question 9

Cat scratch disease

Answer 9

Bacterial infection

• inoculated by the bit or scratch of an infected animal (usually kitten)
• develop lymphadenopathy, fever, and malaise
• most cases resolve within 3-4 months spontaneously

Question 10

Ocular findings of cat scratch disease

Answer 10

• white retinal or choroidal lesions (most common)
• optic head swelling
• exudates around macula
• central scotoma

Question 11

Sarcoidosis

Answer 11

• wide spread non-caseating epithelioid cell granuloma
• fever, malaise, weight loss, pulmonary hilar adenopathy (shortness of breath), parotid adenopathy and lacrimal glands (dry mouth, dry eye), joint disease
• cutaneous lesions. Erythema nodosum, lupus perinio

Question 12

Ocular findings of sarcoidosis

Answer 12

• Eyelid nodules
• Conjunctival and lacrimal gland infiltration
• Acute or chronic anterior uveitis
• Periphlebitis (candlewax drippings)
• spillover retinitis
• pre-retinal nodules
• massive granulomas
• choroiditis

Question 13

Systemic lupus erythematosus (SLE)

Answer 13

• autoimmune disease of CY with many different clinical manifestations
• joints, skin, blood vessels, kidney, heart, lungs, liver, and CNS most often affected
• histroy of arthralgia and fever (92%)
• clinical course marked by spontaneous remission and relapse. Diagnosis is often elusive

Question 14

Cutaneous lesions of lupus

Answer 14

• discoid lupus
• butterfly malar rash
• mucous membrane ulcers
• scarring alopecia
• UV sensitivity

Question 15

Ocular findings of SLE

Answer 15

• eyelid edema
• conjunctivitis and keratitis
• uveitis
• scleritis/episcleritis
• occlusive vasculitis of the retina and the choriocapillaris. Ischemic sequence of NVD, NVE, and RD
• ischemic optic neuropathy

Question 16

Vogt-Koyanagi-Harada syndrome (VKH)

Answer 16

• AKA uveomeningeal syndrome, a systemic disorder involving many organ systems, including the eye, skin, meninges and ear
• common in Asia and parts of Latin America
• caused by chronic inflammation of melanocytes (autoimmune disease)
• the most common symptoms include headaches, inflamamtion of all layers of the colored part of the eye (uveitis), white patches of skin (vitiligo), hair loss (alopecia), dizziness and nausea (inner ear related problems), and vision and hearing loss. Neurological symptoms may also occur

Question 17

Course of the disease: VKH

Answer 17

Develop vision and hearing problems first, followed by signs of skin problems

Question 18

Ocular signs of VKH

Answer 18

• anterior and posterior uveitis. The uveitis is usually bilateral and granulomatous in nature
• inferior exudative retinal detachments. The RPE eventually becomes severely depigmented as the RD resolves. Ultimately, pigmetnary changes in the retina lead to an appearance which has been termed the “sunset glow fundus”
• synechiae and cataract formation are common
• the anterior chamber may become shallow secondary to swelling of the ciliary processes. About 40% of patients develop glaucoma, which may be open or closed angle.