Internal medicine

Electrode

Organic chemistry

Intensive care medicine

Physical chemistry

Chemistry

Urine osmolality

Hyponatremia

Urine

Acid–base imbalance

Water-Electrolyte Balance

Electrolyte Disorder

Sodium

Electrolyte

Clinical diagnosis

Physical examination

Medicine

Kidney International Reports

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.

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