Q. What are Diastix and Keto Diastix reagent strips and how can they help me?
A. Both reagent strips are disposable plastic strips with attached reagent areas, providing a fast and convenient way of testing for urinary glucose and/or ketones (Acetoacetic Acid). 1,2,3
Diastix is a single reagent test for urinary glucose. Keto-Diastix has glucose and ketone reagent tests on a single strip.
Q. Why should I test for glucose?
A. For person with Diabetes, the presence or amount of glucose in the urine can be an indication that your Diabetes may be out of control. By carefully following the testing schedule established by your doctor, both of you can be alerted to any changes in your condition for which adjustments to your treatment may be needed.
Q. What is a ketone and why should I test for this substance?
A. Small amounts of ketone in your body are usually not harmful. However, if you have too much it can be dangerous. Ketones are formed it you burn too much energy and if untreated this could lead to diabetic coma. The presence of ketone is really the body’s signal that something out of the ordinary is happening.
Q. When should I test for ketone?
- When Directed by your Physician or Nurse Educator.
- When you have a cold or ‘flu’, an infection or any other kind of illness.
- When urine glucose test results show 2% or more, or when, if you carry out self blood glucose monitoring, your blood glucose is over the range set by your doctor.
- When under stress e.g: at work, at school, at home or on vacation.
- Regularly during pregnancy or when a testing pattern has been established with your doctor.
Q. How do I do the test?
A. You will need: Reagent Strips, Awatch or timer that measures seconds
- Check the unopened expiration date printed on the bottle lable. Only use reagent strips which have not passed the expiration date.
- Check the date you first opened the bottle and if 6 months have passed, throw the test strips away and use a fresh bottle.
- Collect a fresh urine specimen in a clean, dry container.
- Open the bottle and remove one test strip. Immediately replace cap on the bottle. Hold plastic end of the strip, don not touch the test areas of the strip.
- Dip the test areas of the strip into urine and remove immediately. While removing, draw/wipe edge of strip against the rim of the urine container to remove excess urine. Or, pass the test end of the strip through a stream of urine. Remove excess urine by shaking.Begin timing.
- If using Diastix or Keto-Diastix read the glucose test area by comparing with the color at exactly 30 seconds after wetting.
- If using Keto-Diastix read the ketone test area by comparing with the color chart at exactly 40 seconds after wetting.
- Record results.
- If the color falls between two color blocks, estimate value.
N.B. always read results in good lighting conditions and develop consistent technique in timing and reading results.
Q. How long can I keep reagent strips?
A. A bottle of reagent strips can be used for 6 months after it is first opened. Always write the date you first open the bottle in the space provided on the lable. Do. Not use reagnent strips which have exceded expiry date stated on the bottle label and in case never use a strip which is dicoloured.
Q. What other steps should I take to keep reagent strips fresh?
A. Observe the following points:
- Protect from heat, light and moisture.
- Keep unused strips in original bottle.
- Do not remove desiccant.
- Do not store or open in a steamy bathroom.
- Do not add cotton wool or any other material to bottle.
- Avoid touching reagent areas.
- Store below 30 Degree Celsius. Do not store in refrigerator.
Chemical Principles of the Procedure:
Q. What Chemical Reactions take place when the reagent areas are dipped in urine?
A. Glucose (Diastix and Diastix reagent area of Keto-Diastix). This test is based on a double sequential enzyme reaction. One enzyme, glucose oxidase, catalyzes the formationof gluconic acid, and hydrogen peroxide from the oxidation of glucose. A second enzyme, peroxidase, catalyzes the reaction of hydrogen peroxide with a potassium iodide chromogen to oxidize the chromogen to colors ranging from green to brown.
Ketone (Ketone reagent area of Keto-Diastix). This test is based on the development of colors ranging from buff-pink, for a negative reading to purple when acetoacetic acid reacts with nitroprusside.
Glucose: 2.2% w/w glucose oxidase (Microbial 1.3 IU); 1.0% w/w peroxidase (horseradish 3300 IU); 8.1% w/w potassium iodide; 69.8% w/w buffer; 18.9% w/w nonreactive ingredients.
Ketone: 7.1% w/w sodium nitroprusside; 92.9% w/w buffer.