SPECIMEN COLLECTION AND PREPARATION
Collect urine in a clean container and test as soon as possible. If testing cannot be done within an hour after voiding, refrigerate the specimen immediately and let it return to room temperature before testing. Prolonged exposure of unpreserved urine to room temperature may result in microbial proliferation with resultant changes in pH. 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 effect protein test result. The user should determine whether the use of such skin cleansers is warranted.

LIMITATIONS OF PROCEDURE
pH: If proper procedure is not followed an excess urine remains on the strip, a phenomenon known as "runover" may occur, in which the acid buffer from the protein reagent will run onto the pH areas, causing a false lowering in the pH result.

Protein: False positive result may be obtained with highly buffered or alkaline urine. Contamination of the urine specimen with quatemary ammonium compounds may also produce false positive results.

Glucose: Large amounts of ketone bodies (50 mg/dl or greater) may decrease color development. However, it is unlikely that the presence of ketones simultaneously with glucose in the urine is sufficient to produce false negative results. At glucose levels of 1g/dl or greater, the color may appear somewhat mottled. The darkest color should be used in interpreting results with the color chart. The reactivity of the glucose test decreases as the SG of the urine increases. Reactivity may also vary with temperature.

Ketone: Color reaction that could be interpreted as "positive" may be obtained with urine specimens containing mesena or large amounts of phenylketones or L-dopa metabolites.

EXPECTED VALUES :
pH:3 newborn 5-7 thereafter: 4.5-8 average: 6

SPECIFIC PERFORMANCE CHARACTERISTICS:

Protein Test: Quantitative results are obtained from this test area. Five to 20mg of albumin per dl urine may be detected as a "Trace" result. The test area is more sensitive to albumin than to globulin, hemoglobin and mucoprotein: a negative result, therefore does not rule out the presence of these other proteins.


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QUALITY CONTROL
For best results, performance of reagents strip should be confirmed by testing known negative and positive specimens or controls whenever a new test is performed or whenever a new bottle is first opened. Each laboratory should establish its own goals for adequate standards of performance, and should question handling and testing procedures if these standards are not met.

RESULTS
Results are obtained by direct comparison of the color blocks printed on the bottle label.

Protein: Normally no protein is detectable in urine, although a minute amount is excreted by the normal kidney. A color matching any block greater than Trace indicated significant proteinuria. For urine of high specific gravity, the test area may most closely match the trace color block even though only normal concentrations of protein are present. Clinical judgement is needed to evaluate the significance of trace result.

Glucose: Small amount of glucose are normally excreted by the kidney. Concentrations of as little as 0.1g/dl glucose, read either at 10 or 30 seconds, may be significantly abnormal if found consistently. At 10 seconds, result should be interpreted qualitatively; i.e. negative or positive. For quantitation, read at 30 seconds only.

Ketone: Normally no ketones are present in urine. Detectable levels of ketone may occur in urine during physiological stress conditions such as fasting, pregnancy and frequent strenuous exercise. In starvation diets, or in other abnormal carbohydrate metabolism situation, ketones appear in the urine in excessively large amounts before serum ketones are elevated.

pH Test: The pH test area permits quantitative differentiation of pH values to one unit within the range of 5-9. pH readings are effected by variations in the urinary buffer concentration.

BIBLIOGRAPHY
1. Free, A.H. and free, H.M.: Urinalysis, Critical Discipline of clinical science, CRC Crit.Rev.Clin.Lab.Sci.3(4): 481-531;(1972).
2. Yoder, J..Adams, E.C., and free, H.M. :Simultaneous screening for urinary occult blood, protein, glucose and pH. Amer.J.Med Tech. 31: 285.,(1965)
3. Tietz, N.W.: Clinical guide to laboratory tests; W.B. Sauders Company, (1976)