The osmolality urine test the concentration of particles in
urine. Osmolality (particles/kg water) and osmolarity
(particles/liter of solution) are sometimes confused, but for
dilute fluids such as urine they are essentially the same.
Random specimen: 50 to 1200 milliosmoles per kilogram (mOsm/kg)
12 to 14 hour fluid restriction: Greater than 850 mOsm/kg The
examples above are common measurements for results of these
tests. Normal value ranges may vary slightly among different
laboratories. Some labs use different measurements or test
different samples. Talk to your doctor about the meaning of your
specific test results. Additional conditions under which the
test may be performed: Complicated UTI (pyelonephritis) High
blood sodium level Low blood sodium level Bazari H. Approach to
the patient with renal disease. In: Goldman L, Ausiello D, eds.
Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;
2007:chap 115. David C. Dugdale, III, MD, Professor of Medicine,
Division of General Medicine, Department