1. Retina Case: “External Pallor”
Kevin Lowder, MD – PGY3
03/01/2019

2. Patient Presentation CC HPI Difficulty driving at night
21 yo WF with hx of mild nystagmus OU, p/w difficulty driving at night and light sensitivity. Pt was referred to retina by outside ophthalmology practice for suspected retinal dystrophy given abnormal exam and OCT findings.

3. History (Hx) Past Ocular Hx: Nystagmus OU Ocular Meds: none
PMH: Migraines, HTN, IBS, Anxiety
Fam Hx: Non-contributory
Meds: Linaclotide, Zonisamide, birth control
Allergies: NKDA
Social Hx: Never smoker, no EtOH or drugs
RoS: Negative
Linaclotide = for IBS
Zonisamide = anti-convulsant 3

4. Physical Exam OD OS BCVA 20/30 20/50+2 Pupils 4mm. Round. Brisk.
No rAPD
IOP
14 mmHg
15 mmHg
EOM
full
CVF
Adnexa
Small amplitude nystagmus

6. Physical Exam SLE OD OS External/Lids WNL Conj/Sclera White, Quiet
Cornea
Epithelium intact
Ant Chamber
Normal depth, Quiet
Iris
subtle transillumination defects
Lens
clear

7. Posterior Exam (Fundus Photos)

8. OCT Macula: Foveal Hypoplasia OU
Foveal cut OD
Foveal cut OS

9. Assessment 21 yo WF with ocular albinism Albinoid external appearance
Light sensitivity
Nystagmus
Foveal hypoplasia
Iris transillumination defects
Suboptimal BCVA

10. Other Features: Abnormal decussation of the visual pathways
Normal ~53%; in ocular albinism can be 90%
Strabismus/loss of stereopsis  related to abnormal decussation
Can be tested with VEP
Photophobia
Refractive errors (myopia, hyperopia, astigmatism)
Poor vision (ranging from mild to < 20/200)

11. Main Subsets of Albinism
Oculocutaneous: AR inheritance
Tyrosine-positive: gradually accumulate more pigment
Tyrosine-negative: do not
Chédiak-Higashi syndrome: neutropenia/blood disorder that leads to deadly infections and bleeding
Hermansky-Pudlak syndrome: platelet defect that causes easy bruising and bleeding
(3 P’s: Pigment-less, Platelets, Puerto Ricans)
Ocular albinism: X-linked (most common)
True albinism: fovea is hypoplastic, BCVA is decreased
Albinoidism: (AD) foveal pit is present, VA normal, no nystagmus
Albinoidism = AD with incomplete penetrance

12. Treatment/Plan Observe/treat symptoms Consider genetics consult
Hematology consult if any suspicion for blood disorders

13. References
Kim, JM. (2014, December). Albinism. Retrieved from
Basic Clinical Sciences Course, Section 12: Retina and Vitreous. American Academy of Ophthalmology, Pages 247-8