The association between plasma aldosterone level, transtubular potassium gradient, or their ratios and causes of hyperkalemia in the outpatient setting
Issued Date
2026-03-01
Resource Type
ISSN
11218428
eISSN
17246059
Scopus ID
2-s2.0-105042123583
Pubmed ID
42008517
Journal Title
Journal of Nephrology
Volume
39
Issue
2
Start Page
307
End Page
317
Rights Holder(s)
SCOPUS
Bibliographic Citation
Journal of Nephrology Vol.39 No.2 (2026) , 307-317
Suggested Citation
Wuthapanich T., Phakdeekitcharoen P., Sevamontree C., Phakdeekitcharoen B. The association between plasma aldosterone level, transtubular potassium gradient, or their ratios and causes of hyperkalemia in the outpatient setting. Journal of Nephrology Vol.39 No.2 (2026) , 307-317. 317. doi:10.1093/joneph/aajaf041 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/117477
Title
The association between plasma aldosterone level, transtubular potassium gradient, or their ratios and causes of hyperkalemia in the outpatient setting
Author's Affiliation
Corresponding Author(s)
Other Contributor(s)
Abstract
Background: Hyperkalemia is a lethal condition resulting in cardiac dysrhythmias and death. Identifying the causes of hyperkalemia is crucial for treating and preventing future recurrence. Methods: A prospective cohort study was conducted to evaluate the association between plasma aldosterone level, transtubular potassium gradient, and their ratios in distinguishing the causes of hyperkalemia (serum potassium ≥ 5.8 mmol/L) in the outpatient clinic. Results: Forty-two patients and 26 controls completed the study. The causes of hyperkalemia were classified into three major groups: 1) drug-induced (27 cases), 2) diabetes-related (7 cases), and 3) chronic kidney disease (CKD)-related hyperkalemia (7 cases), and one case of renal tubular acidosis. The mean serum potassium level of the hyperkalemia group was significantly higher than the control group (6.13 ± 0.29 vs 4.27 ± 0.44 mmol/L, P < .001). The mean transtubular potassium gradient values were 3.48 ± 1.87 vs 5.27 ± 1.46, P < .001, respectively. The cut-off aldosterone/transtubular potassium gradient ratio of >2.5 ng/dL or transtubular potassium gradient <5 had comparable sensitivity (64.3% vs 76.2%) and specificity (76.9% vs 53.8%) in discriminating between the hyperkalemia group and the control group, suggesting an inadequate collecting tubule response to hyperkalemia. CKD-related hyperkalemia showed a wide range of transtubular potassium gradients. Lastly, our population was likely to develop diabetes-related hyperkalemia, possibly due to aldosterone resistance from tubular defects. Conclusion: The combined utilization of plasma aldosterone level, transtubular potassium gradient, and their ratios provides a maximum advantage in differentiating causes of hyperkalemia. Additional studies with larger sample sizes and different cut-off serum potassium levels for hyperkalemia are required to further characterize these findings.