Normally, urine contains little to no glucose because kidneys reabsorb filtered glucose.

The FUS test checks for glycosuria (glucose in urine) after fasting for 8–12 hours.

Clinical uses include:

Screening for diabetes mellitus.

Monitoring renal threshold for glucose.

Supporting evaluation of glycosuria due to renal tubular dysfunction.

Less sensitive than blood glucose tests, but still useful in resource‑limited settings.

Often performed alongside Fasting Blood Sugar (FBS) for better diagnostic accuracy.

Analyte: Glucose in urine (mg/dL or qualitative presence).

Normal Result: Negative (no glucose detected).

Abnormal Findings:

Positive urine sugar: Suggests diabetes mellitus or renal glycosuria.

Trace to high levels: Indicates varying severity of glycosuria.

Clinical Use:

Provides a simple screening method for diabetes.

Helps assess renal glucose reabsorption capacity.

Supports monitoring in patients with suspected or known diabetes.