Title:
Dipstick Urinalysis Using
Siemens Reagent Strips
Target Audience: This module is available to aid in
assessing competency for all clinical staff that
performs dipstick urinalysis.
Contents
Instructions ....................................................... 2
Learning Objectives .......................................... 2
Policy & Procedure ........................................... 3-10
Job Aid.............................................................. 11-12
Posttest............................................................. 13-14
Page 1 of 14
Dipstick Urinalysis Using Siemens Reagent Strips
The material in this module serves as an educational tool and aid in assessing competency
for those performing this test within your facility.
•
Read this module which includes the policy and procedure pertinent to this testing.
•
If you have any questions about the material, ask your supervisor or facility POC
Coordinator.
•
Complete the online post test for this module.
•
The Job Aid on pages 11-12 may be customized to fit your department and then
used as a quick reference guide.
•
Completion of this module will be recorded under My Learning in PeopleConnect.
Learning Objectives:
When you finish this module, you will be able to:
1. Demonstrate the proper procedure for performing quality control and testing using
Siemens reagent strips for urinalysis.
2. Describe the proper technique for obtaining and handling of urine specimens for
dipstick urinalysis
3. Identify what substances or conditions may interfere with testing of urine with
dipsticks.
4. Describe what you need to do in the case of quality control that is out of range and not
acceptable.
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Dipstick Urinalysis Using Siemens Reagent Strips
Urinalysis by Siemens® Reagent Strips
(Multistix®, Labstix,
Keto-Diastix®, Albustix®)
I.
PRINCIPLE
Siemens® Reagent Strips for Urinalysis are firm plastic strips to which are affixed
several separate reagent areas. Depending on the product being used, Siemens®
Reagent Strips provide tests for glucose, bilirubin, ketone (acetoacetic acid), specific
gravity, blood, pH, protein, urobilinogen, nitrite and leukocytes in the urine. Please
refer to the carton and bottle label for specific reagent areas on the product you are
using. Test results may provide information regarding the status of carbohydrate
metabolism, kidney and liver function, acid-base balance and urinary tract infection.
II.
PROCEDURE
A. Specimen Information
Collect urine in a clean, dry covered container and test it as soon as possible. If
testing cannot be done within 2 hours after voiding, refrigerate the specimen
immediately for preservation. The use of urine preservatives is not recommended.
Allow the urine specimen to return to room temperature prior to testing.
DO NOT centrifuge specimens. The following specimens are not acceptable for
testing:
1. Specimens that have remained at room temperature for longer than 2 hours.
2. Specimens containing urine preservatives
3. Specimens collected or transported in homemade containers (glass jars, pill
bottles, etc.).
4. Leaking specimen containers.
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Dipstick Urinalysis Using Siemens Reagent Strips
B. Test Method Instructions
MUST BE FOLLOWED EXACTLY TO ACHIEVE RELIABLE TEST RESULTS
1. Collect FRESH urine specimen in a clean, dry container. Mix well immediately
before testing.
2. Remove one strip from bottle and replace cap immediately. Completely
immerse reagent areas of the strip in FRESH urine and remove immediately to
avoid dissolving out reagents. Be sure all of the test pads are wet.
3. While removing, run the edge of the entire length of the strip against the rim
of the urine container to remove excess urine.
• Hold the strip in a horizontal position to prevent possible mixing of
chemicals from adjacent reagent areas and/or contaminating the hands
with urine.
• Blot the strip to remove excess urine by touching the edge to a paper
towel.
• Do not drag the strip across the towel; touch the edge only.
4. Compare reagent areas to corresponding Color Chart on the bottle label at the
time specified.
• HOLD STRIP CLOSE TO COLOR BLOCKS AND MATCH CAREFULLY.
• Avoid laying the strip directly on the Color Chart, as this will result in the
urine soiling the chart.
Proper read time is critical for optimal results. If using strips visually, read the:
• glucose and bilirubin test at 30 seconds after dipping.
ketone test at 40 seconds;
• the specific gravity test at 45 seconds;
• pH, protein, urobilinogen, blood, and nitrite at 60 seconds; and
• leukocytes at 2 minutes.
• pH and protein areas immediately or at any time up to 2 minutes after
dipping.
After dipping the strip, check the pH area. If the color on the pad is not
uniform, read the reagent area immediately, comparing the darkest color to
the appropriate Color Chart. All reagent areas except leukocytes may be read
between 1 and 2 minutes for identifying negative specimens and for determination
of the pH and SG. A positive reaction (small or greater) at less than 2 minutes on
the leukocyte test may be regarded as a positive indication of leukocytes in urine.
Color changes that occur after 2 minutes are of no diagnostic value.
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Dipstick Urinalysis Using Siemens Reagent Strips
C. Reagents
1. Siemens® Reagent Strips (Multistix®, Labstix, Keto-Diastix®, Albustix®)
2. Urinalysis control, Quantimetrix® Dropper Plus, Levels 1 & 2
Reagent Strips must be stored at room temperatures between 15-30°C (5986°F) . Do not use after expiration date on the bottle. Multistix, Labstix, and
Albustix once opened are stable until the expiration date on the bottle.
However, a new bottle of Keto-Diastix Reagent Strips is stable only for six
months after being first opened. Discard 6 months after opening or on
original expiration date, whichever comes first. Record the open date and
new 6 month expiration date on the Keto-Diastix reagent bottle when first
opened. Do not store the bottle in direct sunlight and avoid excessive heat. All
unused strips must remain in the original bottle. Transfer to any other container
may cause reagent strips to deteriorate and become unreactive. Do not remove
desiccant(s) from bottle. Do not remove strip from the bottle until immediately
before it is to be used for testing. Replace cap immediately and tightly after
removing reagent strip because strips are sensitive to moisture. Do not touch
test areas of the reagent strip. IMPORTANT: Protection against ambient
moisture, light, and heat is essential to guard against altered reagent
reactivity. Discoloration or darkening of reagent area may indicate
deterioration. If evident discard strips. Quality control must be run each
time a new bottle of reagent strips is opened. The new bottle of strips must
be dated and labeled “QC’d” on the container to verify quality control was
performed. Ex. QC - 1/1/08.
The Urine Controls must be stored at 2- 8°C (35.6 - 46.4°F) when not in use .
Do not freeze. When stored at 2-8°C, the controls are stable un til the expiration
date stated on the label. After the initial use, the opened Urine control bottles,
when stored at 2-8°C, are stable until the expirati on date stated on the label.
The opened controls may also be stored at room temperature. Do not store above
30°C (86°F). When stored at room temperature (20-2 5°C or 68-77°F), the controls
are stable for one month or until original expiration date, whichever comes first.
The date the control was placed at room temperature and the new one month
expiration date must be recorded on the control bottle label. Discard the controls if
turbid or any evidence of microbial contamination is present.
D. Supplies
1. Stopwatch or watch/clock with second hand
2. Paper towel or absorbent pad
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Dipstick Urinalysis Using Siemens Reagent Strips
E. Quality Control
Two levels of Quality Control must be performed each time a new bottle of
reagent strips are opened and results documented on the Urine Dipstick Quality
Control Log. Quantimetrix® Dropper Plus Urine Dipstick Controls Levels 1 and 2 are
to be used for quality control testing. The bottle of strips must be dated and labeled
“QC’d” on the container to verify quality control was performed. Ex. QC - 1/1/08.
Quality Control Procedure:
1. Remove the controls from the refrigerator and allow them to come to room
temperature (20-25°C), for approximately 15 to 30 m inutes depending on the
volume remaining in the bottle. Mix gently by inversion to assure homogeneity
of the contents. Avoid foaming.
2. Remove one strip from bottle and immediately replace cap.
3. Remove cap of Level 1 control and invert bottle.
• While holding dipstick, apply one drop of control to each reagent pad on
strip.
• Draw across all of the reagent pads, thoroughly saturating each pad.
• Do not aspirate excess control back into the bottle.
• Turn dipstick on its side and drain excess control onto absorbent material.
• Read urine dipsticks visually and compare reagent pads to corresponding
color chart on side of bottle at the specified times.
• Record results on the Urine Dipstick Quality Control Log.
4. Repeat for Level 2 control.
5. Manufacturer Expected ranges must be recorded on the control log. Use the
ranges for Siemens Urinalysis Strips and Visual. These may be found on the
package insert in the box with the controls. These ranges change with every
new lot number of control.
6. Compare quality control results with the manufacturer expected values. If
within range, record the date and “QC” on the container. Ex. QC - 1/1/08.
If controls are not within range, the controls must be repeated until the results
are within range before using the urine dipsticks for patient testing.
NOTE: Patient testing may not be performed if controls do not
demonstrate expected results. The following corrective action must be
taken until acceptable results are obtained:
a.
b.
c.
d.
Repeat test using a reagent strip from the same bottle.
Repeat test using a new control solution.
Repeat test using a reagent strip from a new bottle.
Contact Point of Care office.
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Dipstick Urinalysis Using Siemens Reagent Strips
F. Expected Values
Expected values for the typical “normal” healthy population and the abnormal
population are listed below for each reagent. Exact agreement between visual results
and instrumental results might not be found because of the inherent differences
between the perception of the human eye and the optical system of the instruments.
Glucose: Small amounts of glucose are normally excreted by the kidney. These
amounts are usually below the sensitivity of this test but on occasion may produce a
color between the Negative and the 100 mg/dl color blocks and that is interpreted, by
the instrument in the laboratory, as a positive result. Results at the first positive level
may be significantly abnormal if found consistently.
Bilirubin: Normally no bilirubin is detectable in urine by even the most sensitive
methods. Even trace amounts of bilirubin are sufficiently abnormal and require further
investigation. Atypical colors (colors that are unlike the negative or positive color
blocks shown on the Color Chart) may indicate that bilirubin-derived bile pigments are
present in the urine sample and may be masking the bilirubin reaction. These colors
may indicate bile pigment abnormalities and the urine specimen should be tested
further.
Ketone: Normal urine specimens ordinarily yield negative results with this reagent.
Detectable levels of ketone may occur in urine during physiological stress conditions
such as fasting, pregnancy and frequent strenuous exercise. In ketoacidosis,
starvation or with other abnormalities of carbohydrate or lipid metabolism, ketones
may appear in urine in large amounts before serum ketone concentrations are
elevated.
Specific Gravity: Random urines may vary in specific gravity from 1.001-1.035.
Twenty-four hour urines from normal adults with normal diets and normal fluid intake
will have a specific gravity of 1.016-1.022.
Blood: The significance of the Trace reaction may vary among patients, and clinical
judgment is required for assessment in an individual case. Development of green
spots (intact erythrocytes) or green color (free hemoglobin/myoglobin) on the reagent
area within 60 seconds indicates the need for further investigation. Blood is often, but
not always, found in the urine of menstruating females. This test is highly sensitive to
hemoglobin and thus complements the microscopic examination.
pH: Both the normal and abnormal urinary pH range is from 5-9.
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
indicates 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
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Dipstick Urinalysis Using Siemens Reagent Strips
protein are present. Clinical judgment is needed to evaluate the significance of Trace
results.
Urobilinogen: The normal urobilinogen range obtained with this test is 0.2 to 1.0
mg/dl (1 mg/dl is approximately equal to 1 Ehrlich Unit/dl). A result of 2.0 mg/dl
represents the transition from normal to abnormal, and the patient and/or urine
specimen should be evaluated further.
Nitrite: Normally no nitrite is detectable in urine. The proportion of positive nitrite tests
in cases of significant infection depends on how long the urine specimens were
retained in the bladder prior to collection. Identification of known positive cases with
the nitrite test ranges from as low as 40%, when little bladder incubation occurred, to
as high as approximately 80%, when a minimum of four hours of bladder incubation
occurred.
Leukocytes: Normal urine specimens generally yield negative results; positive results
(Small or greater) are clinically significant. Individually observed Trace results may be
of questionable clinical significance; however, Trace results observed repeatedly may
be clinically significant. Positive and repeated Trace results indicate the need for
further testing of the patient and/or urine specimen, according to medically accepted
procedures for pyuria. Positive results may occasionally be found with random
specimens from females due to contamination of the specimen by vaginal discharge.
G. Interpretation of Results
Ensure that the following is recorded in the patient’s medical record: date, time, test
results and initials of person who performed test.
Results should be recorded as follows:
Glucose: Negative or 100 to ≥2000 mg/dl
Bilirubin: Negative or Small(+) to Large(+++)
Ketone: Negative or Trace(5mg/dl) to Large(160mg/dl)
Specific Gravity: 1.000 to 1.030
Blood: Negative to Large(+++)
pH: 5.0 to 8.5
Protein: Negative-Trace or 30mg/dl(+) to ≥2000mg/dl(+++)
Urobilinogen: 0.2 to 1mg/dl or 2 to 8mg/dl
Nitrite: Negative or Positive
Leukocytes: Negative or Trace to Large(+++)
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Dipstick Urinalysis Using Siemens Reagent Strips
H. Method Limitations
Substances that cause abnormal urine color, such as drugs containing azo dyes (e.g.,
Pyridium®, Azo Gantrisin®, Azo Gantanol®), nitrofurantoin (Macrodantin®,
Furadantin®), and riboflavin, may affect the readability of the reagent areas on
urinalysis reagent strips. The color development on the reagent pad may be masked,
or a color reaction may be produced on the pad that could be interpreted visually
and/or instrumentally as a false positive.
Glucose: Ascorbic acid concentrations of 50 mg/dl or greater may cause false
negatives for specimens containing small amounts of glucose (75-125 mg/dl). Ketone
bodies reduce the sensitivity of the test; moderately high ketone levels (40 mg/dl) may
cause false negatives for specimens containing small amounts of glucose (75-125
mg/dl) but the combination of such ketone levels and low glucose levels is
metabolically improbable in screening. The reactivity of the glucose test decreases as
the Specific Gravity of the urine increases. Reactivity may also vary with temperature.
Bilirubin: Indican (indoxyl sulfate) can produce a yellow-orange to red color response
that may interfere with the interpretation of a negative or positive bilirubin reading.
Metabolites of Lodine® (etodolac) may cause false positive or atypical results; ascorbic
acid concentrations of 25 mg/dl or greater may cause false negatives. Since very
small amounts of bilirubin may be found in the earliest phases of liver disease, the
user must consider whether the sensitivity of Siemens Reagent Strips to bilirubin is
sufficient for the intended use.
Ketone: False positive results (Trace or less) may occur with highly pigmented urine
specimens or those containing large amounts of levodopa metabolites. Compounds
such as mesna (2-mercaptoethane sulfonic acid) that contain sufhydryl groups may
cause false positive results or an atypical color reaction.
Specific Gravity: The chemical nature of the Siemens SG test may cause slightly
different results from those obtained with other specific gravity methods when elevated
amounts of certain urine constituents are present. Highly buffered alkaline urines may
cause low readings relative to other methods. Elevated specific gravity readings may
be obtained in the presence of moderate quantities (100-750 mg/dl) of protein.
Blood: Elevated specific gravity may reduce the reactivity of the blood test. Capoten®
(captopril) may also cause decreased reactivity. Certain oxidizing contaminants, such
as hypochlorite, may produce false positive results. Microbial peroxidase associated
urinary tract infection may cause a false positive reaction. Levels of ascorbic acid
normally found in urine do not interfere with this test.
pH: If proper procedure is not followed and 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 area, causing a false lowering of the pH result.
Page 9 of 14
Dipstick Urinalysis Using Siemens Reagent Strips
Protein: False positive results may be obtained with highly buffered or alkaline urines.
Contamination of the urine specimen with quaternary ammonium compounds (e.g.,
from some antiseptics and detergents) or with skin cleansers containing chlorhexidine
may also produce false positive results.
Urobilinogen: The reagent area may react with interfering substances known to react
with Ehrlich’s reagent, such as p-aminosalicylic acid and sulfonamides. Atypical color
reactions may be obtained in the presence of high concentrations of p-aminobenzoic
acid. False negative results may be obtained if formalin is present. Strip reactivity
increases with temperature; the optimum temperature is 22°-26°C. The test is not a
reliable method for the detection of porphobilinogen. The absence of urobilinogen
cannot be determined with this test.
Nitrite: Pink spots or pink edges should not be interpreted as a positive result. Any
degree of uniform pink color development should be interpreted as a positive result
suggesting the presence of 100,000 or more organisms per ml, but color development
is not proportional to the number of bacteria present. A negative result does not in
itself prove that there is no significant bacteruria. Negative results may occur when
urinary tract infections are caused by organisms that do not contain reductase to
convert nitrate to nitrite; when urine has been retained in the bladder long enough
(four hours or more) for reduction of nitrate to nitrite to occur; or when dietary nitrate is
absent, even if organisms containing reductase are present and bladder incubation is
ample. Sensitivity of the nitrite test is reduced for urines with high specific gravity.
Ascorbic acid concentrations of 25 mg/dl or greater may cause false negative results
with specimens containing small amounts of nitrite ion (0.06 mg/dl or less).
Leukocytes: Elevated glucose concentrations (> 3 g/dl) or high specific gravity may
cause decreased test results. The presence of cephalexin (Keflex®), cephalothin
(Keflin®), or high concentrations of oxalic acid may also cause decreased test results.
Tetracycline may cause decreased reactivity, and high levels of the drug may cause a
false negative reaction.
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Dipstick Urinalysis Using Siemens Reagent Strips
JOB AID
MULTISTIX URINE DIPSTICK
SAMPLE:
U
Urriinnee
CONTROL REQUIREMENTS:
TWO levels of control every time a new bottle of strips is opened.
Write “QC and the date” on bottle to confirm QC was performed.
CONTROL STORAGE:
date on bottle.
Refrigerated at 2-8 oC (36-46 oF). Stable until expiration
STRIP STORAGE:
Room Temperature. Stable until expiration date on bottle. The
strips are sensitive to light and moisture and must remain in bottle tightly capped until
ready to use for testing.
CONTROL PROCEDURE:
1) Allow controls to come to room temperature. Mix gently.
2) Remove test strip from bottle and immediately replace cap.
3) Add one drop of control to each reagent pad on strip. Turn dipstick on its side to
drain excess.
4) Read dipstick exactly at specified times carefully comparing color to chart on side
of bottle.
5) Record results on Control Log and compare to expected results. The expected
values change with every lot number of control and are located on the manufacturer
insert in the box with the controls. If any result is not within expected range, the
control must be repeated. If still out, repeat using new control. If still out, repeat
using new bottle of strips. If still out, contact Point-of-Care office 355-3466.
*** Patient testing may not be performed if controls do not give expected results.
PATIENT TEST PROCEDURE:
1) Collect urine specimen and test as soon as possible within 1 hour of collection.
2) Mix urine well immediately prior to testing.
3) Remove test strip from bottle and immediately replace cap.
4) Completely immerse reagent areas of strip in FRESH urine and remove immediately
to avoid dissolving out reagents.
5) Run the edge of the entire strip against the rim of the urine container to remove
excess urine.
6) Hold strip in a horizontal position.
7) Read dipstick exactly at specified times carefully comparing color to chart on side
of bottle.
Page 11 of 14
Dipstick Urinalysis Using Siemens Reagent Strips
CAUSES OF FALSE RESULTS:
• Substances that cause abnormal urine color such as drugs containing
dyes (ex. Pyridium and Azo-Gantrisin) may affect the readability of the
reagent areas on the urinalysis reagent strips. Color development may
be masked, or a color reaction may be produced on the pad that could
be interpreted as a false result.
• Urine specimens contaminated with vaginal discharge may result in a
false positive leukocyte test suggesting patient has white blood cells
present in their urine.
• The leukocyte block on the reagent strip is to be read in 2 minutes
exactly. If the leukocyte block is not read at 2 minutes, false results
may be obtained.
• After 1 hour at room temperature, bacteria can begin to multiply giving
false positive results for nitrite suggesting the patient has an infection.
• Using dipsticks that have not been kept in a tightly closed bottle.
Strips exposed to light and moisture may give inaccurate results.
• Not reading each test result at the specified time. Reading the test
result before or after the specified time can result in inaccurate results.
Page 12 of 14
Dipstick Urinalysis Using Siemens Reagent Strips
Posttest
Name: __________________________________
Date:______________
Acknowledgement of Module Content review (Check appropriate response):
I have read the module contents: Dipstick Urinalysis Using Siemens reagent strips.
Yes □
No □
1. Urine control results must be compared to the expected values supplied by the manufacturer on the
package insert in the box of controls to determine if they are acceptable.
a) True
b) False
2. The urine sample must be used within two hours from the time of collection.
a) True
b) False
3. Substances that cause abnormal urine color such as drugs containing dyes (ex. Pyridium and
Azo-Gantrisin) may affect the readability of the reagent areas on the urinalysis reagent strips.
a) True
b) False
4. Urine specimens contaminated with vaginal discharge may result in a false positive leukocyte test
on the reagent strip.
a) True
b) False
5. Each test on the dipstick must be read at the specified read time or results may be inaccurate.
a) True
b) False
6. Patient testing can be performed even if controls do not perform as expected.
a) True
b) False
7. The leukocyte block on the reagent strip is to be read in how many minutes?
a)
b)
c)
d)
Five minutes
0ne minute
Two minutes
Ten minutes
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Dipstick Urinalysis Using Siemens Reagent Strips
8. For each bottle of urine dipsticks two levels of quality control must be performed and documented
a) Daily
b) Each time a new bottle is opened
c) With each patient test
9. What must be recorded on the urine dipstick bottle upon opening?
a)
b)
c)
d)
Open date
“QC’d” (for Quality Control performed)
Nothing
Both a and b
Page 14 of 14