Oculocutaneous albinism type 2

What it is

From: Orphanet

A form of oculocutaneous albinism characterized by variable hypopigmentation of the skin and hair, numerous characteristic ocular changes and misrouting of the optic nerves at the chiasm.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Abnormality of refraction · Frequent (79-30%)

An abnormality in the process of focusing of light by the eye in order to produce a sharp image on the retina.

Abnormality of retinal pigmentation · Frequent (79-30%)

Any deviation from the normal pigmentation of the retina.

Blue irides · Frequent (79-30%)

A markedly blue coloration of the iris.

Freckling · Frequent (79-30%)

The presence of an increased number of freckles, small circular spots on the skin that are darker than the surrounding skin because of deposits of melanin.

Heterochromia iridis · Frequent (79-30%)

Heterochromia iridis is a difference in the color of the iris in the two eyes.

Hypopigmentation of the skin · Frequent (79-30%)

A reduction of skin color related to a decrease in melanin production and deposition.

Hypoplasia of the fovea · Frequent (79-30%)

Underdevelopment of the fovea centralis.

Iris hypopigmentation · Frequent (79-30%)

An abnormal reduction in the amount of pigmentation of the iris.

Iris transillumination defect · Frequent (79-30%)

Transmission of light through the iris as visualized upon slit lamp examination or infrared iris transillumination videography. The light passes through defects in the pigmentation of the iris.

Macular hypopigmentation · Frequent (79-30%)

Decreased amount of pigmentation in the macula.

Nystagmus · Frequent (79-30%)

Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.

Optic nerve misrouting · Frequent (79-30%)

Abnormal decussation of the visual pathways, typically identified using visual evoked potentials (VEP) (asymmetrical distribution of the VEP over the posterior scalp).

Photophobia · Frequent (79-30%)

Excessive sensitivity to light with the sensation of discomfort or pain in the eyes due to exposure to bright light.

White eyebrow · Frequent (79-30%)

White color (lack of pigmentation) of the eyebrow.

Other findings in the same source

From: Orphanet

Additional reported features include White hair (Frequent (79-30%)); Hypopigmentation of hair (Frequent (79-30%)); Reduced visual acuity (Frequent (79-30%)); Absent skin pigmentation (Occasional (29-5%)); Basal cell carcinoma (Occasional (29-5%)); Cutaneous melanoma (Occasional (29-5%)); Posterior staphyloma (Occasional (29-5%)); Squamous cell carcinoma of the skin (Occasional (29-5%)); White eyelashes (Occasional (29-5%)); Hyperpigmented nevi (Very rare (<4-1%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Infancy; Neonatal

Inheritance in the source

From: Orphanet

Autosomal recessive

Frequency and the population described

From: Orphanet

Point prevalence: 1-9 / 100 000; Worldwide; Value and class. Point prevalence: 6-9 / 10 000; Specific population; Value and class. Point prevalence: 6-9 / 10 000; Tanzania, United Republic of; Value and class. Point prevalence: 1-9 / 100 000; United States; Value and class.

Understanding the inheritance label

From: MedlinePlus Genetics

An autosomal recessive pattern usually involves disease-causing changes in both copies of a gene. Parents may each carry one altered copy without having the condition themselves. A genetic counsellor can explain carrier testing and reproductive implications using the actual laboratory findings, rather than the condition name alone.

Which doctor should you see?

The suggested department for discussing Oculocutaneous albinism type 2 is Dermatology, with a dermatologist as the relevant type of clinician. Dermatologist; paediatric services for children as appropriate.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Which features of the skin, hair or nails distinguish the possibilities?
• Would photographs over time help document the changes?
• What should be expected from treatment, and how will irritation or other adverse effects be managed?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Oculocutaneous albinism type 2. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.