The Role of Uric Acid in Inflammasome-Mediated Kidney Injury

Tarcio Teodoro Braga; Orestes Foresto-Neto; Niels Olsen Saraiva Camara


Curr Opin Nephrol Hypertens. 2020;29(4):423-431. 

In This Article

The Role of Uric Acid in Kidney Injuries

The increased number of patients with end-stage renal disease is largely because of the aging of the population, associated with the increased incidence of diseases such as type 2 diabetes and hypertension. The mechanisms leading to the establishment of chronic kidney disease (CKD) are complex and, despite progress in the last decades, are still not completely understood. A number of hemodynamic, metabolic and inflammatory factors are known to be related and interconnected to promote the progressive loss of nephrons, leading to the replacement of the renal parenchyma by scar tissue.[18,74,75] Increase in circulating uric acid levels has also been associated with occurrence of human CKD.[76]

Hyperuricemia is present in 20–35% of patients with progressive renal diseases.[77,78] Although hyperuricemia is usually asymptomatic, crystals of monosodium urate can precipitate in tissues such as articular synovium, causing gout in patients with CKD, and inside the tubular lumen, promoting crystal-induced kidney damage.[79] In addition, uric acid nephrolithiasis can be caused by aciduria.[80] Rarely high urine uric acid excretion can induce uric acid stone formation in kidneys.[81] Evidence suggests an association between uric acid stones and higher prevalence of CKD.[82] However, progressive kidney disease as a consequence of urolithiasis is recognized only in a small percentage of stone formers.[83] Although increased sUA levels are also detected in kidney tissue of hyperuricemic patients,[84] whether hyperuricemia without crystal formation is a real risk factor or just a biomarker of progressive kidney injury is still unclear.