Isosthenuria describes a fixed urine specific gravity that is around which value across serial samples?

Isosthenuria describes a fixed urine specific gravity that is around which value across serial samples?

• A. 1.000
• B. 1.007
• C. 1.020
• D. 1.010

Answer: (D)

Isosthenuria reflects a kidney that can no longer modify urine concentration, so the urine stays essentially the same as plasma in terms osmolality. This yields a specific gravity that hovers around the level of plasma, about 1.010, and it remains roughly the same across serial samples even if you drink more water or take in fluids. Healthy kidneys can produce more concentrated urine or more dilute urine, depending on hydration, but with isosthenuria the concentrating/diluting ability is lost, so the SG stays near 1.010.

Isosthenuria reflects a kidney that can no longer modify urine concentration, so the urine stays essentially the same as plasma in terms osmolality. This yields a specific gravity that hovers around the level of plasma, about 1.010, and it remains roughly the same across serial samples even if you drink more water or take in fluids. Healthy kidneys can produce more concentrated urine or more dilute urine, depending on hydration, but with isosthenuria the concentrating/diluting ability is lost, so the SG stays near 1.010.