Nutritional interventions for patients with alkaptonuria: A minireview.

Area of Science:

• Biochemistry
• Metabolic disorders
• Genetics

Background:

• Alkaptonuria (AKU) is a rare genetic disorder caused by homogentisate 1,2-dioxygenase deficiency, leading to homogentisic acid accumulation and ochronosis.
• AKU causes severe joint problems, fractures, and osteoporosis.
• Nitisinone, approved in 2020, effectively reduces homogentisic acid but induces hypertyrosinemia.

Purpose of the Study:

• To address the adverse effects of nitisinone-induced hypertyrosinemia in AKU patients.
• To explore novel nutritional approaches for managing AKU treatment complications.
• To mitigate the negative impact on skeletal muscle metabolism.

Main Methods:

• Review of nitisinone's mechanism and side effects in AKU.
• Analysis of dietary interventions for hypertyrosinemia.
• Evaluation of nutritional impacts on muscle metabolism in AKU.

Main Results:

• Nitisinone treatment significantly lowers homogentisic acid levels.
• Hypertyrosinemia is a key side effect, potentially causing corneal keratopathy.
• Low-protein diets, while reducing keratopathy risk, lead to poor tolerance, muscle loss, and weight gain.

Conclusions:

• Nitisinone is effective for AKU but poses risks due to hypertyrosinemia.
• Current dietary management is challenging and detrimental to muscle health.
• Development of new nutritional strategies is crucial for AKU patients on nitisinone.