What urine glucose level is considered abnormal?

An abnormal urine glucose level indicates that glucose is present in the urine, which typically should not occur unless blood glucose levels are elevated beyond the renal threshold for glucose reabsorption. When blood glucose levels exceed approximately 180 mg/dL, the kidneys are unable to reabsorb all the glucose, resulting in its appearance in urine.

A urine glucose level of 250 mg/dL or greater indicates a significant overflow of glucose into the urine, often associated with conditions such as diabetes mellitus, where hyperglycemia is prevalent. Therefore, this level serves as a clinical indicator for further investigation into the patient's blood glucose levels and potential metabolic issues.

The other options suggest levels that would be considered normal or borderline, highlighting that glucose at these lower thresholds is typically reabsorbed adequately by the kidneys, maintaining a negative or minimal presence in urine.