From the Guidelines
Having just one kidney can potentially lead to higher uric acid levels due to reduced kidney function and filtration capacity. When you have only one kidney, that single kidney must handle the entire filtration workload normally shared by two kidneys, which can reduce the overall filtration capacity. Uric acid is a waste product that needs to be filtered by the kidneys and excreted in urine. With reduced kidney function, uric acid may accumulate in the bloodstream, resulting in elevated levels. This is particularly concerning because high uric acid can lead to conditions like gout (painful joint inflammation) or kidney stones.
According to the 2020 American College of Rheumatology guideline for the management of gout 1, considerations for patients with chronic kidney disease (CKD) should be taken into account, as higher starting doses and CKD are associated with risk of acute hyperuricemia syndrome. Additionally, a study on autosomal dominant tubulointerstitial kidney disease 1 suggests that patients with hyperuricemia should be treated with losartan, as it is the only agent that lowers serum urate levels owing to increased urinary urate excretion.
If you have a single kidney, it's essential to monitor your uric acid levels regularly through blood tests. Your doctor might recommend medications like allopurinol or febuxostat to manage high uric acid if necessary, as suggested by the medical management of kidney stones guideline 1. Some key points to consider include:
- Maintaining adequate hydration (at least 2-3 liters of water daily)
- Limiting alcohol consumption
- Reducing intake of purine-rich foods (like red meat, organ meats, and certain seafood)
- Maintaining a healthy weight These measures can reduce the burden on your remaining kidney and help keep uric acid levels within normal range. Regular monitoring and lifestyle modifications are crucial to preventing complications associated with high uric acid levels in individuals with a single kidney.
From the Research
Uric Acid and Kidney Function
- The kidneys play a crucial role in regulating serum uric acid levels, with approximately two-thirds of uric acid produced in humans being excreted by the kidneys 2.
- Abnormal serum levels of uric acid are due to alterations in production or excretion, and fractional excretion of uric acid can help determine the underlying etiology of hypouricemia or hyperuricemia 3.
Hyperuricemia and Kidney Disease
- Hyperuricemia is seen when kidney function declines, and elevated uric acid levels may play a role in the initiation and progression of kidney disease 4.
- Observational studies suggest a relationship between uric acid levels and incident chronic kidney disease (CKD), but the evidence is conflicting 4.
- Some studies suggest that lowering uric acid levels may retard the progression of CKD, and that uric acid may be an important factor in the pathogenesis of acute kidney injury (AKI) and CKD 3, 5.
Having One Kidney and Uric Acid Levels
- There is no direct evidence to suggest that having one kidney will lead to high uric acid levels.
- However, having one kidney may affect the body's ability to excrete uric acid, potentially leading to hyperuricemia 3, 2.
- Further studies are needed to clarify the association between uric acid and kidney disease, particularly in individuals with a single kidney 4, 2.
Treatment of Hyperuricemia in CKD
- Febuxostat, a novel xanthine oxidase inhibitor, has been shown to effectively reduce serum uric acid concentrations and may suppress the progressive decline in renal function in patients with CKD 5, 6.
- Allopurinol, another uric acid-lowering therapy, has also been used to treat hyperuricemia in CKD patients, but its effectiveness in retarding kidney disease progression is less clear 6.