Urine specific gravity

From WikiMD.com Medical Encyclopedia

Urine Specific Gravity[edit | edit source]

Urine specific gravity measurement using a refractometer.

Urine specific gravity (USG) is a measure of the concentration of solutes in the urine. It is a valuable diagnostic tool used to assess the kidney's ability to concentrate or dilute urine and is an important parameter in evaluating a patient's hydration status and renal function.

Physiology[edit | edit source]

The kidneys play a crucial role in maintaining the body's fluid and electrolyte balance. They filter blood, reabsorb essential substances, and excrete waste products in the form of urine. The specific gravity of urine reflects the kidney's ability to concentrate or dilute urine relative to plasma.

Urine specific gravity is influenced by the amount of solutes such as electrolytes, urea, and glucose present in the urine. A higher specific gravity indicates more concentrated urine, while a lower specific gravity suggests more dilute urine.

Measurement[edit | edit source]

Urine specific gravity can be measured using a refractometer, a urinometer, or reagent strips. The refractometer is a precise instrument that measures the refractive index of urine, which correlates with its specific gravity. Reagent strips provide a quick and convenient method but may be less accurate.

Clinical Significance[edit | edit source]

Dehydration[edit | edit source]

In cases of dehydration, the body conserves water, leading to more concentrated urine and a higher specific gravity. Monitoring urine specific gravity can help assess the severity of dehydration and guide rehydration therapy.

Renal Disorders[edit | edit source]

Urine specific gravity is an important parameter in diagnosing and monitoring renal disorders. In conditions such as chronic kidney disease, the kidneys may lose their ability to concentrate urine, resulting in a fixed low specific gravity.

Diabetes Insipidus[edit | edit source]

In diabetes insipidus, the kidneys are unable to concentrate urine due to a deficiency of antidiuretic hormone (ADH) or a lack of response to ADH. This results in the production of large volumes of dilute urine with a low specific gravity.

Related Pages[edit | edit source]



WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates, categories Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD