Before glucose meters were available, urine glucose was frequently used to approximate diabetic glucose levels. Blood glucose levels can be related to urine glucose concentration because of urinary excretion of glucose. Physician offices, clinics, and patients at home tested urine with reagent strips for semi-quantitative measurement of urine glucose, and adjustments in insulin therapy were made. However, monitoring a diabetic patient for carbohydrate management is seldom performed in this manner today. A portable meter measurement of blood glucose is a much better management method. Urine glucose measurement is neither sensitive nor specific and does not give information about blood glucose below the renal threshold (approximately 180 mg/dL).
As a semiquantitative measurement, urine glucose is a routine assay and an abnormal result would be further investigated using assays for blood glucose levels. If quantitative measurements are needed, a timed urine specimen can be collected and measured for glucose by blood glucose methods.