增多

痛風, 腎功能損傷, 多發性骨髓瘤, 妊娠高血壓綜合症,攝入大量核酸物質(如動物內臟)

減少

急性肝壞死, 用腎上腺皮激素, 秋水仙鹼或阿司匹林等藥物

或 Wilson's disease, Fanconi's syndrome, xanthinuria, and (paradoxically) in some neoplasms, including Hodgkin's disease, myeloma, and bronchogenic carcinoma.