|
SYMPTOMS
|
Decrease in vision, Photophobia, Decrease in depth perception
|
|
SIGNS
|
Bilateral
|
|
Light color irides, Diffuse iris transillumination defects, Blonde fundus from the periphery to the posterior pole, Foveal hypoplasia
|
|
WORK-UP
|
Pupils, EOMs (may present with a pendular nystagmus), Color vision, Full eye exam with dilation, Visual field, OCT of the macula, Fundus Autofluorescence, Fluorescein Angiography, Fundus photos, Infrared photos, Electrodiagnostic testing (VEP: Abnormal due to irregular decussation of nerve fibers at the chiasm / ERG / EOG), Dark adaptation, Amsler grid
|
|
TREATMENT
|
Monitor
|
|
Limit sun exposure as these patients have an increased risk of skin cancer
|
|
Recommend sunglasses/UV protection
|
|
Consider specialty contact lenses
|
|
Recommend genetic counseling for other family members
|
|
If the patient develops poor vision, refer to low vision
|
|
FOLLOW-UP
|
Patient should be seen back in 6-12 months
|
|
ADDITIONAL LAB | TESTS
|
Genetic testing: OCA, BOCA, OA
|
|
Tyrosinase hair bulb test, Possible hematologic counseling
|
|
ETIOLOGY
|
Occurs due to abnormal tyrosinase and a subsequent decrease in melanin
|
|
Oculocutaneous albinism is autosomal recessive and is associated with reduced amounts of melanin in each melanosome (involves the eyes, hair, and skin)
|
|
Ocular albinism is x-linked and is associated with a reduced number of melanosomes (involves only the eyes)
|
|
DIFFERENTIAL DX
|
Retinitis pigmentosa, Choroideremia, Gyrate atrophy
|
|
NOTES
|
Visual acuity can be anywhere from 20/40 to 20/400
|
|
Signs and symptoms of ocular albinism are less severe than oculocutaneous albinism
|
|
Patients with albinism can have very high myopic, hyperopic, and astigmatic refractive errors
|
|
True albinism presents with reduced vision and a nystagmus. Albinoidism presents with normal vision and no nystagmus
|
|
Female carriers of ocular albinism may have diffuse iris transillumination defects and a blonde fundus
|
|
Hermansky-Pudlak syndrome: Oculocutaneous albinism with associated platelet storage deficiency which leads to easy bleeding and bruising
|
|
Chediak-Higashi syndrome: Oculocutaneous albinism with increased risk of infection
|
