From the Research
Perioral manifestations of alkaptonuria include blue-black pigmentation of the lips, gums, and teeth due to homogentisic acid deposition, and management focuses on symptomatic treatment with regular dental hygiene and cosmetic camouflage products, as well as consideration of nitisinone therapy to slow pigment accumulation. The most recent and highest quality study on the management of alkaptonuria, 1, suggests that dietary restriction of tyrosine and phenylalanine can help lower tyrosinemia associated with nitisinone therapy, which may be beneficial in managing the systemic effects of the disease. Key aspects of management include:
- Regular dental hygiene with professional cleanings every 3-6 months to address tooth discoloration
- Use of cosmetic camouflage products for visible pigmentation of the lips and oral mucosa
- Consideration of nitisinone (2 mg/day orally) to inhibit the enzyme that produces homogentisic acid, potentially slowing pigment accumulation
- Monitoring by both dental professionals and physicians experienced with alkaptonuria, as the oral findings are part of a systemic disorder affecting multiple body systems The underlying pathophysiology involves deficiency of homogentisic acid oxidase enzyme, leading to accumulation and polymerization of homogentisic acid in connective tissues throughout the body, including oral structures, as described in 2 and 3. While perioral manifestations are primarily cosmetic concerns, they can cause psychological distress requiring supportive counseling as part of comprehensive management, and the use of nitisinone has been shown to be effective in reducing homogentisic acid levels, as demonstrated in 4.