Strips (Urine) Package Insert
For rapid detection of multiple analytes in human urine.
For in vitro diagnostic use only.
The Urinalysis Reagent Strips (Urine) are firm plastic strips onto which several separate reagent areas are affixed. The test is for the qualitative and semi-quantitative detection of Creatinine, and Albumin at low concentrations also known as Microalbumin in urine. The test can also provide an Albumin to Creatinine Ratio from a random single-void specimen by visual or urine analyzer reading.
Urine undergoes man changes during states of disease or body dysfunction before blood composition is altered to a significant extent. Urinalysis is a useful procedure as an indicator of health or disease, and as such, is a part of routine health screening. The Urinalysis Reagent Strips (Urine) can be sued in General evaluation of health, and aids in the diagnosis and monitoring of metabolic or systemic diseases that affect kidney function, endocrine disorders and iseases or disorders of the urinary tract.1,2
The test is also used to screen samples for microalbuminuria which may help determine which patients are at risk of developing early kidney damage. The development of glomerular damage, in the absence of nephropathy, may be predicted by microalbuminuria.
Patients with the highest risk are those with diabetes and hypertension, followed by patients who have immune disorders or have been exposed to nephrotoxins. Microalbuminuria may also be an early indication of developing preeclampsia during pregnancy.6
PRINCIPLES AND EXPECTED VALUES
Albumin: The basis for the test is a high affinity sulfonephthalein dye, using the dye binding method
to produce any blue color if albumin is present at a constant pH. Results range in color from pale green to aqua blue. Normally, albmin is present in urine at concentrations < 20 mg/L.11 Results of 20-200 mg/L may indicate
micralbuminuria. It is associated with early-stage kidney disease when a small amount of Albumin, also called Microalbumin is consistently present in urine.
Clincial albuminuria is indicated by results of >200 mg/L. These levels can be predictive of albumin excretion rates of 30-300 mg/24hours and >300 mg/24hours, respectively.12-13 Exercise, acute illness and fever, and urinary tract infections may temporarily elevate urinary Albumin excretions.
Creatinine: The peroxidase-like activity of a copper creatinine complex catalyzes the reaction of diisopropylbenzene dihydroperoxide and 3,3′,5,5′-tetramethylbenzidine to produce a resulting color range from orange through green to blue. Creatinine concentrations of 10-300 mg/dL are normally present in urine.
Albumin-toCreatinine Ratio: It is also called Microalbumin-to-Creatinine ratio which is the most accurate and easiest test available to assess microalbuminuria. Albumin is normally present in urine at concentrations of <30 mg albumin/g creatinine.
Microalbuminuria is indicated at a ratio result of 30-300 mg/g (Abnormal) and clinical albuminuria at a ratio of >300 mg/g (High Abnormal).9
REAGENTS AND PERFORMANCE CHARACTERISTICS
Based on the dry weight at the time of impregnation, the concentrations given may vary within manufacturing tolerances. The following table below indicates read times and performance characteristics for each Parameter.
buffer; nonreactive ingredients
between 10-150 mg/L
diisopropylbenzene dihydroperoxide; 3,3′,5,5′-tetramethylbenzidine; buffer; nonreactive ingredients
between 10-300 mg/dL (0.9-26.5 mmol/L)
The Performance characteristics of the Urinalysis Reagent Strips (Urine) have been determined in both laboratory and clinical tests. Parameter of importance to the user are sensitivity, specificity, accuracy and precision. Generally, this test has been developed to be specific for the parameters to be measured with the exceptions of the interferences listed. Please refer to the Limitations section in this package insert. Interpretation of visual results s dependent on several factors: the variability of color perception, the presence or absence of inhibitory factors, and the lighting conditions when the strip is read. Each color block on the chart corresponds to a range of analyte concentrations.
- For in vitro diagnostic use only.
- Do not use after the expiration date.
- The strips should remain in the closed canister or the sealed pouch until use.
- To prevent against altered reagent reactivity, protect strips from ambient moisture, light, and heat.
- Do not touch the reagent areas of the strip.
- Discard any discolored strips that may have deteriorated.
- All specimens should be considered potentially hazardous and handled in the same manner as an
- The used strip should be discarded according to local regulations after testing.
- Follow the directions exactly for accurate results.
- Use fresh urine specimens for optimal results.
STORAGE AND STABILITY
Store as packaged in the closed canister of the sealed pouch either at room temperature or refrigerated (2-30C). Keep out of direct sunlight. The strip is stable thorough the expiration date printed on the canister label or the sealed pouch. Do not remove the desiccant. Remove only enough strips for immediate use. Replace cap immediately and screw tightly. DO NOT FREEEZE. Do not use beyond the expiration date.
Note: Once the canister has been opened, the remaining strips are stable for up to 3 months.
Strips packaged in the sealed pouch should be used immediately after opening.
Stability may be reduced in high humidity conditions.
SPECIMEN COLLECTION AND PREPERATION
A urine specimen must be collected in a clean and dry container and tested as soon as possible. Do not centrifuge. The use of urine preservatives is not recommended but the only urine preservative recommended is Boric acid, at a concentration of 1.0 g/L. If testing cannot be done within an hour after voiding, refrigerate the specimen immediately and let it return to room temperature before testing.
Prolonged storage of unpreserved urine at room temperature may result in microbial Proliferation with resultant changes in pH and loss of albumin. A shift to alkaline pH may cause false positive results with the protein test area. Urine containing glucose may decrease in pH as organisms metabolize the glucose. Contamination of the urine specimen with skin cleansers containing chlorhexidine may affect protein (and to a lesser extent, specific gravity and bilirubin) test results.
Store specimens at 0-8C (32-46 F) for one week or at -20C (68F) for one month without significant effect on test results.
Any urine specimen that is single-voided can be used to discriminate between normal and abnormal levels of microalbuminuria.7-9 First-morning specimens are recommended.10 Testing three urine samples over a three-to-six month period may increase the predictive value because urinary albumin changes daily.
When two out of three samples are positive samples, these positive samples are predictive of incipient nephropathy.4,9 To determine the Albumin excretion rate, twenty-four hour or timed collections may also be used with this test. For additional information on screening guidelines, refer to the American Diabetes Association Position Statement.9 It is recommended to screen the urine for protein rather than albumin. A specimen with a Protein test result of ≥30 mg/dL should not be tested with Urinalysis Reagent Strips containing Albumin analyte.
Materials Required But Not Provided
DIRECTIONS FOR USE
Allow the strip, urine specimen, and/or controls to reach room temperature (15-30C) prior to testing.
1. Remove the Strip from the closed canister and use it as soon as possible. Immediately close the canister tightly after removing the required number of strip(s). Completely immerse the reagent areas of the strip in fresh, well-mixed urine and immediately remove the strip to avoid dissolving the reagents.
2. While removing the strip from the urine, run the edge of the strip against the rim of the Urine container to remove excess urine. Hold the strip in a horizontal position and bring the edge of the strip into contact with an absorbent material (e.g. a paper towel) to avoid mixing chemicals from adjacent reagent areas and/or soiling hands with urine.
3. Compare the reagent areas to the corresponding color blocks on the canister label or color chart at the specified times. Hold the strip close to the color blocks and match carefully.
Note: Results may be read up to 2 minutes after the specified times. Dip the test strip slowly into the urine specimen to avoid bubbles on the reagent area. If there is a bubble present, repeat the test by dipping the strip more slowly into the urine specimen.
INTREPRETATION OF RESULTS
Results are obtained by direct comparison of the color blocks printed on the canister label. The color blocks represent nominal values; actual values will vary close to the nominal values. In the event of unexpected or questionable results, the following steps are recommended; confirm that the specimens have been tested within the expiration date printed on the canister label, compare results with known positive and negative controls and repeat the test using a new strip.
Note: Water should not be used as negative control. If the problem persists, discontinue using the strip immediately and contact your local distributor.
Refer to following table to determine the albuminto-creatinine ratio.
||Recollect specimen *
* If specimen is too dilute to accurately determine ratio result. Repeat test on new specimen, preferably a first-morning collection.
** Both Albumin and A:C ratio results should be taken under consideration to determine clinical diagnosis decision or the need for confirmatory testing.
Note: Within several seconds after dipping, there may be a quick change in color on the albumin pad. Make sure to wait until the color stabilizes and until the 60 second reading time, before making a final reading.
Visually interpreted test results compared to urine analyzer interpreted result may provide different results because the urine analyzer determines the intermediate correlation value and uses a specific software calculation to determine the approximate albumin to creatinine ratio.
Variations in visual results may be due to visual interpretation limitations for each parameter result. For example, a single specimen has an albumin concentrations of 25 mg/l and creatinine concentration of 100mg/dl. Because the
test is semi-quantitative, visual reading will give the corresponding albumin color block at 30mg/l. By using only visual interpretation, the albumin to creatinine ratio would be 30mg/g and considered abnormal. When a urine analyzer
is used to interpret results, the algorithm used to calculate the albumin to creatinine ratio uses a value closer to the true quantitative value for albumin of 25mg/l. With the analyzer interpretated albumin results, this may cause the
albumin to creatinine ratio to be 25mg/g and considered normal.
For best results, performance of reagent strips should be confirmed by testing known positive and negative specimens/controls whenever a new test is performed, or whenever a new canister or a sealed pouch from a new lot is first opened. Each laboratory should establish its own goals for adequate standards of performance.
Note: The Urinalysis Reagent Strips (Urine) may be affected by substances that cause abnormal urine color such as drugs containing azo dyes (e.g. Pyridium, Azo Gantrisin, Azo Gantanol), nitrofurantoin (Microdantin, Furadantin), and
riboflavin. Urine specimen contaminated with soaps, detergents, antiseptics, or skin cleansers, or the use of urine preservatives other than boric acid (1.0 g/L), may also affect test results. The color development on the test pad may
be masked or a color reaction may be produced that could be interpreted as false results. As with all diagnostic and therapeutic tests, all results must be considered with other clinical information available to the physician.
Falsely elevated results with both the albumin and creatinine tests can occur in the presence of hemoglobin or myoglobin (≥5mg/dL or visible bloody urine).
All positive results for albumin including low concentrations of Albumin also known as Microalbumin should be confirmed with quantitative test methods.
The albumin test in contrived urine detects albumin at a concentration of 20-40 mg/L. Because of clinical urines‘ inherent variability, lesser concentrations may be detected under certain conditions. Both albumin and albumin-to-creatinine ratio should be considered during decision making regarding clinical diagnosis or need for confirmatory testing. This test is specific for albumin and is not affected by the following proteins when tested at concentrations at least nine times greater than the excretion rate considered to be abnormal:14
lysozyme, Bence-Jones protein, α1-acid glycoprotein, prealbumin, Tamm Horsfall glycoprotein, α1-microglobulin, immunoglobulins, β2-microglobulin, α1-antitrypsin, haptoglobin, β2-glycoprotein, retinal binding protein, transferring. High specific gravity urine and/or high alkali urine may cause falsely elevated results with the microalbumin test.
Creatinine: This test detects urinary creatinine in concentrations as low as 10 mg/dl; the absence of creatinine in a specimen can not be determined. A new specimen such as a first-morning collection should be tested.
- Free AH, Free HM. Urinalysis, Critical Discipline of Clinical Science. CRC Crit. Rev. Clin. Lab. Sci. 3(4): 481-531, 1972.
- Yoder J, Adams EC, Free, AH. Simultaneous Screening for Urinary Occult Blood, Protein, Glucose, and pH. Amer. J. Med Tech. 31:285, 1965.
- Mogensen, C.E.: Microalbuminuria Predicts Clinical Proteinuria and Early Mortality in Maturity-Onset Diabetes. N. Eng. J. Med. 310: 356-360; 194.
- Mogensen, C.E. et al: Prevention of Diabetic Renal Disease with Special Reference to Microalbuminuria. Lancet 346: 1080-1085; 1985.
- Kaplan, N.M.: Microalbuminuria: a Risk Factor for Vascular and Renal Complications of Hypertension. Am. J. Med.92: 8S-12S; 1992.
- Nisell, H. et al: Renal Function in Gravidas with Chronic Hypertension With and Witout Superimposed Preclampsia. J. Hypertens. Pregnancy 15: 127-134; 1996.
- Nathan, D.M.; Rosenbasum, C.; and Protasowicki, V.D.: Single-void Urine Samples Can be Used to Estimate
Quantitative Microalbuminuria Diabetes Crare 10: 414-418; 1987.
- Ginsberg, J.M. et al: Use of single Voided Urine Samples to Estimate Quantitative proteinuria. N. Wng. J. Med. 309: 1543-1456; 1983.
- Position Satement: Diabetic Nephropathy. Diabetes Care 20: S24-S27; 1997.
- Cowell, C.T.; Rogers, S.; and Silink, M.: First Morning Urinary Albumin Concentration is a Good Predictor of 34-Hour Urinary Albumin Excretion in Children with Type 1 (Insulin-Dependent) Diabetes. Diabetologia 29: 97-99; 1986.
- Burtis, C.A. and Ashwood, E.R.: Tietz Textbook of Clinical Chemistry, 3rd ed. Philadelphia: Saunders; 1999; pp. 483-484.
- Mangili, R. et al.: Prevalence of Hypertension and Microalbuminuria in Adult Type 1 (Insulin-Dependent) Diabetic patients Without Renal Failure in Italy-Validation of Screening Techniques to Detect Microalbuminuria. Acta Diabetol. 29: 156-166; 1992.
- American Diabetes Association, Clincal Practice Recommendations, Diabetes Care, Vol. 31, Suppl. 1, January 2008.
- Pugia, M.J. et al.: Comparions of Urine Dipsticks with Quantitative Methods for Microalbuminuria. Eur. J. Clin. Chem. Biochem. 35(9): 693-700; 1997.
Effective date: 2013-08
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