Sugar in the urine is also known as a positive urine glucose on a routine urine test, which can show up as (+) to (++++). Normally, glucose in the blood is filtered through to the renal tubules, which are able to reabsorb all of the glucose, so normal people are negative for glucose in urine. However, there is a limit to the ability of the renal tubules to reabsorb glucose, beyond which glucose will appear in the urine, and the blood glucose concentration at which glucose appears in the urine is the renal glucose threshold. The sugar in urine mainly includes two conditions: First, high blood glucose or diabetes, when the patient’s blood glucose is too high, too much glucose filters through to the renal tubules, exceeding the ability of the renal tubules to reabsorb glucose will appear positive for urine glucose, depending on the degree of elevated blood glucose, which can be expressed as (+) to (++++). Second, a decrease in the renal glucose threshold, if the renal tubular capacity to reabsorb glucose decreases, the presence of sugar in the urine can occur even though the blood glucose is not high, as seen in women with kidney disease or pregnancy.