What are the precautions that must be followed when using urine testing strip?

SAFETY MEASURES MUST BE TAKEN: GLOVES MUST BE WORN; SMOKING, EATING, DRINKING, APPLICATION OF COSMETICS, AND MANIPULATION OF CONTACT LENSES ARE PROHIBITED IN ALL TECHNICAL WORK AREAS.� REFER TO THE UNIVERSAL PRECAUTIONS POLICIES.

CLIA Complexity: Waived-Definitive

I.������ Principle

Chemstrip uGK test strips are for the semiquantitative visual estimation of glucose and ketones in urine.

Glucose:

The glucose reagent area has two distinct zones of different reagent concentrations specifically designed to provide optimal sensitivity to urine glucose levels ranging from 100 to 5,000 mg/dL.� Both zones of the reagent area contain the enzymes glucose oxidase and peroxidase, and the color indicator tetramethylbenzidine.� D-glucose is oxidized to gamma-D-gluconolactone with glucose oxidase acting as a catalyst.� The hydrogen peroxide that results from the reaction oxidizes the indicators in the presence of peroxidase.� The intensities of the colors formed are proportional to the glucose concentration of the specimen.

Ketones:

The detection of ketone bodies in urine is based on the method attributed to Legal.

II.����� Specimen

Prior to collecting the patient�s sample, the patient�s identity must be verified by looking at the arm band. If it is an outpatient, verbally verify patient�s name and date of birth with patient or parent/guardian.� Collect urine in a clean container that will allow complete immersion of test strip area. Test as soon as possible after collection.� Do not centrifuge specimen.� If testing cannot be performed within one hour after collection, the specimen should be refrigerated immediately at 2-80C and returned to room temperature prior to testing.� Mix thoroughly before testing.

III.���� Reagents

Chemstrip uGK Urine Test Strips (Cat. No. 00513).

Store at room temperature below 30�C; do not freeze.

Label vial with date opened; do not use after expiration date.

Caution: Test strips contain nitroferricyanide.� Do not touch the reagent pads with skin or mucous membranes; if contact occurs flush with large amounts of water.

Timer or watch with a second hand

IV.���� Procedure

1.������ Collect fresh urine specimen in clean, dry container.� Mix well before testing.

2.������ Remove one test strip from bottle and replace cap immediately.� Completely immerse reagent area in urine and remove immediately to avoid dissolving out reagents.

3.������ While removing, run the edge of the strip against the rim of the urine container to remove excess urine.

4.������ Start timing for two minutes. After two minutes, match the colors on the test strip with the color blocks printed on the vial label.� Any color changes after three minutes are not important.

5.������ DO NOT COMPARE TEST STRIP FROM ONE VIAL� WITH THE COLOR CHART ON ANOTHER VIAL (DIFFERENT LOT NUMBER). THIS COULD CAUSE MISINTERPRETATION.� EACH COLOR CHART IS MADE TO MATCH THE TEST STRIPS FOR THAT LOT NUMBER.

6.������ When the colors of the glucose test patch are between the color blocks on the vial, then glucose test result is between those color blocks.� Compare both glucose color blocks at the same time.

7.������ If the ketone turns from beige to violet, the test is positive.

�

V.������ Quality Control

A.����� Reagents

Quantimetrix urine dipstick controls, normal and abnormal level; prepared from human urine to which is added predetermined amounts of chemicals. Liquid, ready-to-use.

B.������ Storage and Stability

Stable until expiration date stated on label, when stored between 2� to 8�C.� Controls can be stored up to one month at room temperature.� Label control vials with open date and room temperature expiration date.� DO NOT FREEZE.

C.������ Procedure

1.������ On initial use, remove the control tube from the refrigerator and allow to reach room temperature prior to testing.

2.������ Remove cap and invert bottle.� While holding reagent strip, gently squeeze the sides of the dropper bottle and touch the tip of the bottle to the test pad.� Thoroughly saturate the reagent pads.� Turn the dipstick on its side and drain excess control onto absorbent material.

3.������ Read the dipstick according to the procedure above.

4.������ Wipe off dropper tips and recap controls.� The controls can be stored at room temperature for up to one month when not in use.

5.������ Record results on the Quality Control Log Sheet.

D.����� Frequency

Two levels of quality control (normal and abnormal) should be run once a week.� Controls should also be run whenever a new vial of uGK Reagent Strips is opened.

E.������ Troubleshooting

If quality control results are not within the acceptable limits the following steps should be taken:

1.������ Confirm that the strips and controls are within the opened expiration dates shown on the label.

2.������ Repeat test with fresh control material. If still out of range, go to step 3.

3.������ Repeat test with new vial of test strips.

4.������ Discard any controls or reagent strips which gave invalid test results.

5.������ Do not use strips for patient testing if quality control results are out of range.

VI.���� Expected Results

Glucose or ketones should not be detected in normal urine.� A positive reaction indicates a need for further diagnostic evaluation of the patient.� Critical Values are up to the assessment of the physician.�

VII.��� Limitations

Glucose:

False negative or falsely lowered glucose readings may occur rarely at high concentrations of ascorbic acid.� Highly colored urine (i.e. due to certain medications or bilirubin) may the color reaction and prevent accurate readings.� Glucose values must be determined within three minutes of starting the test.

Ketones:

2-Mercaptoethane sulphonate sodium and other sulfhydryl-containing compounds may cause false positive results.� Ketone values must be determined within the specified three minute time limits.

VIII.�� Competency Checks

Competency checks are performed during at initial orientation, after 6 months of employment, and yearly thereafter by the POC Medical Technologist or a validated nurse.

IX.����� References

1.������ Legal E. Chem Centr. 14:652 (1883)

2.������ Zweig M. Clin. Chem. 32/4, 674-677 (1986)

3.������ Chemstrip uGK Urine Test Strips, package insert.� Boehringer Mannheim Diagnostics.� Indianapolis, IN.� 1988.

4.������ The dropper Plus Urine Dipstick Control Kit, package insert. Quantimetrix Corporation, Hawthorne, CA.� September, 1993.� ������

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