Interpreting the Results of the Dipstick Test

The substances the dipstick tests for are shown in figure 1 and discussed below.

Leukocyte Esterase

Leukocyte esterase is an enzyme produced by white blood cells. If the urine tests positive for leukocyte esterase, then whole or lysed white cells are in the urine. The presence of white blood cells could indicate a urinary tract infection or other issues with the urinary system.

Nitrite

Healthy urine contains nitrates, a type of nitrogen chemical. However, when bacteria, such as E. coli, enter the urinary tract, these bacteria turn these nitrates into nitrites, a different nitrogen chemical. A positive nitrite test indicates bacteria are present that could cause a urinary tract infection.

Urobilinogen

Bilirubin is converted into urobilinogen by intestinal bacteria. Urobilinogen is excreted in feces, transported to the liver, or converted into bile. About 1% of urobilinogen is excreted in the urine, and normal values range between 0.2 and 1 mg/dL. An increase in urobilinogen levels can indicate a problem with the liver.

Protein

It is normal to have either no protein or trace levels of protein in the urine, but significantly elevated protein levels can indicate a kidney problem or diabetes mellitus. The normal protein level in a random urine sample should not exceed 15 mg/dL; in a urine sample collected over 24 hours, it should not exceed 80 mg/dL.

pH

The normal pH level for urine ranges from 4.8 to 8.0. Very acidic urine, with a pH less than 4.8, can indicate the formation of urinary stones or diabetic ketoacidosis. Very alkaline urine, with a pH greater than 8, can indicate a urinary tract infection or kidney problems. However, both diet and medication can alter pH.

Blood

Blood in the urine can indicate many disorders and needs a secondary check-up. Possible causes include a urinary tract infection, kidney stones, kidney disease, or cancer. Menstrual bleeding can contaminate the urine sample, which should be considered.

Specific Gravity

The specific gravity of urine is a measure of the amount of solute dissolved in urine, and it indicates the kidneys’ ability to balance water content and excrete waste. The normal range for urine is between 1.005 to 1.030. A low specific gravity can suggest an inability to concentrate urine, excessive hydration, or diabetes insipidus. A high specific gravity can be indicative of dehydration or diabetes mellitus.

Ketones

When your body doesn't have enough sugar, the liver will start breaking down fat and producing ketones. The body uses ketones as fuel, and some are excreted. Causes of ketones in urine include fasting, low-carb diets, and health conditions such as diabetes mellitus. The normal range for ketones is less than 20 mg/dL.

Bilirubin

Bilirubin is not present in the urine of normal healthy individuals. Bilirubin is a product of the breakdown of red blood cells. It is usually filtered by the liver and converted into bile. Detectable levels of bilirubin in urine can indicate a problem with the liver, such as liver disease.

Glucose

Usually, glucose levels in urine are almost undetectable because less than 0.1% of glucose filtered by the glomerulus appears in the urine. Typically the glucose levels in a random urine sample are less than 15 mg/dL, and in a urine sample collected over 24 hours, the glucose level should be less than 130 mg/dL. Higher glucose values could indicate diabetes mellitus.

Figure 1: The reference values for a dipstick test. On the left are the names of substances being detected and the times the pads need before you can read the result.