Читать книгу Uric Acid in Chronic Kidney Disease - Группа авторов - Страница 21

The renal handling of uric acid involves a complex 4-component system in which uric acid is first filtered and then extensively reabsorbed, followed by tubular secretion and postsecretory reabsorption. Secretion and reabsorption are probably distributed coextensively throughout the proximal and, perhaps, distal tubules, thereby preventing an inordinately high concentration of urate within the tubular lumen at any single location [1].

Most patients with gout have normal excretion rates of uric acid and yet maintain sustained hyperuricemia. This observation implies the presence of an inefficient mechanism for renal tubular excretion of uric acid in these patients. It is known that by using the antituberculous drug pyrazinamide, which is thought to block renal tubular secretion of urate, for a given serum level of uric acid, patients with gout have a lower rate of uric acid secretion than do normal individual. This defect, in essence, requires an increased preload of uric acid in the serum in order that the daily production of uric acid to be excreted by the gouty patient’s kidney. So the urate deposit is probably initiated outside the tubular lumen [2].