Use of Urine Electrolytes and Urine Osmolality in the Clinical Diagnosis of Fluid, Electrolytes, and Acid-Base Disorders

Kamel S Kamel; Mitchell L Halperin

doi:10.1016/j.ekir.2021.02.003

Use of Urine Electrolytes and Urine Osmolality in the Clinical Diagnosis of Fluid, Electrolytes, and Acid-Base Disorders

Kidney Int Rep. 2021 Feb 13;6(5):1211-1224. doi: 10.1016/j.ekir.2021.02.003. eCollection 2021 May.

Authors

Kamel S Kamel^{1

2}, Mitchell L Halperin¹

Affiliations

¹ Renal Division, St. Michael's Hospital and The University of Toronto, Toronto, Ontario, Canada.
² Keenan Research Center in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.

Abstract

We discuss the use of urine electrolytes and urine osmolality in the clinical diagnosis of patients with fluid, electrolytes, and acid-base disorders, emphasizing their physiological basis, their utility, and the caveats and limitations in their use. While our focus is on information obtained from measurements in the urine, clinical diagnosis in these patients must integrate information obtained from the history, the physical examination, and other laboratory data.

Keywords: hyperkalemia; hypokalemia; hyponatremia; polyuria; renal tubular acidosis; urine electrolytes; urine osmolality.

Publication types

Review