Urinsyre

Urinsyre, or uric acid, is a weak organic acid and a natural product of purine metabolism in humans and some other primates. It is formed mainly in the liver as the end product of purine degradation and is excreted from the body primarily by the kidneys, with a portion eliminated via the gastrointestinal tract. Unlike many other animals, humans lack the enzyme uricase, which converts uric acid further into more soluble compounds, so uric acid is present in higher levels in the body and is the principal physiological end product of purine catabolism.

Chemically, uric acid exists in equilibrium with its conjugate base urate at physiological pH. It has relatively low solubility in water, and high concentrations can crystallize as monosodium urate, particularly in joints or kidneys. Such crystal formation is associated with gout and can contribute to kidney stones. Uric acid also functions as an antioxidant in plasma, though its role in health and disease is complex and context-dependent.

Clinical relevance involves managing uric acid levels to prevent or treat gout, kidney stones, and related conditions. Hyperuricemia can result from overproduction or reduced excretion. Treatments include dietary modification to limit purines, hydration, and medications such as xanthine oxidase inhibitors (allopurinol, febuxostat) to reduce production, uricosurics (e.g., probenecid) to enhance excretion, and, in refractory cases, enzymes like pegloticase that metabolize uric acid. Measurement of serum uric acid is a common part of evaluating metabolic and renal health.