What is the definition of specific gravity in relation to urine analysis?

Specific gravity in urine analysis refers to the density of urine compared to that of distilled water. It provides important information about the concentration of solutes in urine, which can reflect the kidney's ability to concentrate or dilute urine based on the body's hydration status.

When measuring specific gravity, it is crucial to understand that distilled water has a specific gravity of 1.000. If urine has a specific gravity greater than 1.000, it indicates that the urine is more concentrated, suggesting a higher level of solutes such as electrolytes, urea, and creatinine. Conversely, a specific gravity less than 1.000 suggests dilute urine, which could indicate overhydration or certain pathologies affecting kidney function.

The other choices do not accurately define specific gravity. The volume of urine produced relates to output but does not involve density comparisons. The amount of protein in urine is related to urine composition but does not involve density, and the pH level of urine assesses acidity or alkalinity rather than concentration or density. This distinction is essential in understanding renal function and diagnosing various medical conditions.