Abnormal renal tubular resorption Impaired renal tubular reabsorption of glucose 2022-09-04T19:42:47Z Increased fractional excretion (FE) of glucose in the urine. The FE of glucose is the percentage of the glucose filtered by the kidney which is excreted in the urine. It is measured in terms of plasma and urine glucose, rather than by the interpretation of urinary glucose concentration alone, as urinary glucose concentrations can vary with water reabsorption.