E70.320 Tyrosinase negative oculocutaneous albinism

Name of the Condition

• Tyrosinase negative oculocutaneous albinism (ICD-10-CM Code: E70.320)

Summary

Tyrosinase negative oculocutaneous albinism is a rare genetic disorder characterized by a complete absence of melanin pigment in the skin, hair, and eyes. This condition results in significant visual impairment and distinct physical features due to the lack of melanin, which is essential for normal pigmentation and eye development.

Causes

Tyrosinase negative oculocutaneous albinism is caused by mutations in the TYR gene, which encodes the enzyme tyrosinase. This enzyme is critical for the initial steps of melanin synthesis. Mutations in this gene disrupt melanin production, leading to the absence of pigment in affected tissues.

Risk Factors

• Genetic inheritance; typically autosomal recessive, requiring mutations in both copies of the TYR gene.
• Family history of albinism or consanguinity (parents who are closely related).

Symptoms

• Pale or white skin, hair, and light-colored eyes (often blue or pinkish).
• Severe vision problems, including nystagmus, strabismus, photophobia, and reduced visual acuity.
• Increased risk of sunburn and skin damage due to lack of melanin protection.

Diagnosis

Diagnosis involves a physical exam to assess pigmentation, ocular evaluations by an ophthalmologist, and genetic testing to confirm mutations in the TYR gene. Clinical evaluation is essential, as newborn screening may not detect this specific subtype.

Treatment Options

Management focuses on symptom relief: corrective lenses for vision problems, protective eyewear for photophobia, and regular skin monitoring for damage or cancer. Genetic counseling may be recommended for families.

Prognosis and Follow-Up

Individuals with tyrosinase negative oculocutaneous albinism typically experience lifelong visual impairment but can lead healthy lives with appropriate care. Regular follow-up with ophthalmologists and dermatologists is important to manage complications.

Complications

• Severe vision impairment, including legal blindness in some cases.
• Increased risk of skin cancers due to sun sensitivity.
• Social or psychological challenges related to appearance and vision.

Lifestyle & Prevention

• Use broad-spectrum sunscreen and protective clothing to reduce sunburn risk.
• Wear sunglasses or tinted lenses to manage photophobia.
• Regular eye exams and skin checks to monitor for complications.

When to Seek Professional Help

Seek medical attention if you notice new or worsening vision changes, severe sunburn, or unusual skin lesions. Early intervention can help manage symptoms and prevent complications.

Tips for Medical Coders

Document the specific subtype (tyrosinase negative) and confirm genetic testing results when available. Ensure clinical documentation supports the diagnosis to justify code assignment.