Is it absolute that when urine sugar is high, blood glucose will be proportionately higher? What is the relationship between blood and urine sugar levels? Does urine quantity effect glucose level by losing more or less glucose in urine?

The concentration at which the capacity for the renal tubules to reabsorb glucose is exceeded is always at a glucose concentration in the blood that is in the range above normal. Normal glucose Tmax (concentration above which the tubules cannot reabsorb glucose) is generally set at around 180 mg/dl [10.0 mmol/L]. This can actually change to lower values with age and makes it more likely that older people with diabetes have glucosuria at lower levels of glucose than were present when they were younger, but still higher than the normal value of 70 mg/dl [3.9 mmol/L] to 140 mg/dl [7.8 mmol/L]. The amount of glucose lost results in a loss of calories, weight loss, and muscle mass loss. In addition, the constant high glucose in the urinary track is probably a risk for urinary tract infections.

JTL