Which of the following test results are not determined by a urine dipstick?

• A. Glucose
• B. BUN
• C. Blood
• D. Total protein

Answer: (B)

Urine dipsticks detect certain substances in urine by color changes on chemically treated pads after contact with the sample. They are designed to screen for glucose, blood, and protein because these can appear in urine under various conditions. Glucose in urine occurs when blood glucose is high and the kidneys spill it into the urine; the glucose pad uses an enzymatic reaction to produce a color change. Blood in urine is detected through a peroxidase-like reaction from heme, indicating the presence of red blood cells or free hemoglobin. Protein detection, usually mainly albumin, indicates proteinuria and can point to kidney issues or other disorders.

BUN, or blood urea nitrogen, is a measure of nitrogenous waste in the blood and is not determined by a standard urine dipstick. It requires a blood test (and sometimes specialized urine testing) to assess kidney function or hydration status.