Urine Chemistries

Urine chemistries are frequently ordered by clinicians managing hospitalized patients with the following problems: acute kidney injury, volume depletion, hypernatremia, hyponatremia, polyuria, metabolic acidosis, metabolic alkalosis, and disorders of potassium balance. This article focuses on the appropriate use and interpretation of urine chemistries commonly measured in a spot urine sample in the hospitalized patient. Common pitfalls and limitations to the use of urine chemistries are also addressed.