Albinism

Question 1

Ocularalbinism etiology

Answer 1

Decreased melanosomes

Question 2

Oculocutaneous albinism etiology

Answer 2

Decreased melanin in all melanosomes

Tyrosine +/-

Question 3

Signs of ocular albinism

Answer 3

Iris transilluminationdefects, diffuse hypopigmentation of the fundus, decreased acuity, and nystagmus

Question 4

What is albinism

Answer 4

Rare, inherited disorder that is a genetic mutation leading to a total or partial lack of MELANIN

Question 5

Inheritance of ocular albinism

Answer 5

X linked recessive

Question 6

Inheritance of oculocutaneous albinism

Answer 6

AR

Question 7

What other systemic problem is albinism associated with

Answer 7

Deafness

Question 8

Tyrosine positive oculocutaneous albinism

Answer 8

Tyrosinase is present, but has impaired function, resulting in a reduction (but not complete lack of) melanin within the melanosomes

Question 9

Melanocytes

Answer 9

1 out of every 10 cells in the body is a melanocytes. This cell has an organelle called and melanosome that is responsible for production of melanin. Darkly pigmented skin, hair, and eyes have melanosomes that contain more melanin (not melanosomes)

Question 10

Differentials for photophobia

Answer 10

Anterior uveitis
Corneal pathology
Ectropion uveae
Ocular/oculocutaneous albinism

Question 11

Ectropion uveae

Answer 11

Rare neural crest cell disorder characterized by the proliferation of the pupillary ruff iris posterior pigmented epithelium onto the anterior surface of the iris. Advanced cases may lead to glaucoma and peripheral contraction of the iris (leading to photophobia). Associated with NF, Rieger’s anomaly, variant aniridia, and other disorders

Question 12

Vision loss and albinism

Answer 12

The degree of vision loss in ocular and oculocutaneous albinism corresponds with the amount of foveal hypoplasia, VA typically ranges from 20/40 to 20/400. Nystagmus is the result of foveal hypoplasia, but does not significantly contribute to reduced VA. Diffuse iris TIDs cause photophobia.

Question 13

Treatment for albinism

Answer 13

Refer to hematology to rule out associated symptoms. Oculocutaneous albinism may be associated with Chediak-Higashu and Hermansky-Pudlak syndromes, which are genetic syndromes associated with severe systemic complications. Although there is no treatment for albinism itself, the ocular symptoms can be managed with low vision aids, tints, and specialty CLs. Strabismus surgery can also be considered to improve cosmesis in concerned patients

Question 14

Drugs that can cause blue scleras

Answer 14

Minocycline and oral corticosteroids

Question 15

Atropine side effects

Answer 15

Dry mouth, dry flushed skin, rapid pulse, fever, and disorientation due to CNS effects on the hypothalamus

Question 16

Side effects of ethambutol

Answer 16

Retrobulbar optic neuritis

Question 17

Isotretinoin side effects

Answer 17

Blepharoconjunctivitis, DED, pseudotumor cerebri, eyelid edema, loss of color vision, nyctalopia, and cataracts

Question 18

Drugs for TB

Answer 18

RIPE
Rifampin 
Isoniazid
Pyrazinamide
Ethambutol