PRAXISDIENST Actim CRP Instruction Manual
- June 3, 2024
- PRAXISDIENST
Table of Contents
PRAXISDIENST Actim CRP Instruction Manual
Instructions for use
Test procedure and results
Numbers 1 – 10 refer to illustrations on inner cover.
Structure of dipstick
Intended use
The Actim® CRP test is a visually interpreted, semiquantitative immunochromatographic dipstick test, which is used for determination and monitoring of CRP concentrations in whole blood samples. The test is intended for professional use.
Kit components
The Actim CRP kit (31031ETAC) contains 20 CRP test packs with instructions for use. The components of each Actim CRP test pack (31021ETAC) are:
- One dipstick in a sealed aluminum foil pouch with desiccant.
- One tube of Specimen Dilution Buffer solution (0.5 ml). The buffer contains buffer salts, bovine serum albumin (BSA) and preservatives.
Each kit contains a vial of 10 μl end-to-end capillaries (20). Alternatively,
other 10 capillaries or a pipette may be used for sample collection (not
available with the kit).
Lancets or lancing devices are needed if samples are taken from fingertips.
Storage
Store the test kit at +2…+25 °C. Stored unopened, each component can be used until the expiry date marked on the component. Open the foil pouch and remove the dipstick from the pouch just prior to use.
Specimen collection
The sample is 10 μl of whole blood diluted in Specimen Dilution Buffer. The diluted sample can be kept at room temperature for 8 hours.
Sampling from the fingertip with the end-to-end capillary
Use a lancet or a lancing device to obtain a drop of blood from a fingertip. Take the sample with the 10 μl capillary 5 . Make sure that the capillary becomes filled with blood. Immediately drop the capillary into the Specimen Dilution Buffer tube. Mix the sample into the buffer by inverting the tube upside down 10- 15 times until you see that the sample has completely transferred into the buffer (no visible whole blood in the capillary) 6 .
Sampling from a whole blood sample tube
EDTA, citrate or heparin blood can also be used as a sample. The sample can be
pipetted from the blood sample tube with a 10 μl pipette. Dispense the sample
into the Specimen Dilution Buffer tube and mix the sample into the buffer.
Test procedure and interpretation of the results
- If stored refrigerated, allow the aluminum foil pouch and the buffer tube to reach room temperature. Open the foil pouch containing the dipstick by tearing. Do not touch the yellow dip area at the lower part of the dipstick. Identifying marks may be written on the upper green part of the dipstick. The dipstick must be used shortly after its removal from the foil pouch.
- Allow the specimen to reach room temperature before testing. Place the yellow dip area (the lower end of the dipstick) into the diluted sample 7 and hold it there until you see the liquid front enter the result area 8 . Remove the dipstick from the solution and place it in a horizontal position.
- The result is available in 5 minutes 9 . Do not pay attention to any lines appearing later than 5 minutes.
If, in addition to the red control line there are
- no blue lines, the serum CRP concentration of the sample is <10 mg/l
- one blue line, the serum CRP concentration is 10-40 mg/l
- two blue lines, the serum CRP concentration is 40-80 mg/l
- three blue lines , the serum CRP concentration is >80 mg/l
If the control line does not appear, the test is invalid 10.
The intensities of the blue lines will vary. When the CRP concentration is low
(10-15 mg/l) only one faint blue line appears in 5 minutes. As the
concentration of CRP increases, the intensity of the first line increases. A
second blue line begins to appear when the concentration exceeds 40 mg/l.
Correspondingly, for concentrations between 40 and 80 mg/l the second blue
line becomes more intense. A third blue line begins to appear when the CRP
concentration exceeds 80 mg/l.
Limitations of the test
The test is intended for in vitro diagnostic use only
Notes
-
The test requires 150 μl of diluted sample to ensure proper performance of the test.
-
Care must be taken when placing the dipstick in the sample tube. The upper part of the dipstick must stay dry.
-
Do not use a dipstick that has become wet before use, because moisture damages the dipstick.
-
Do not use a dipstick if you notice a blue or red coloring in the result area before testing.
-
Do not use a dipstick if its aluminum foil pouch or the seals are not intact.
-
When dipping, be careful to hold the dipstick in position (with the dip area in the diluted sample) until the sample liquid front reaches the result area.
-
The red control line is in the upper part of the result area. Depending on the CRP concentration, up to three blue lines indicating different concentrations of CRP become visible starting from the lower end of the result area.
Appearance of a control line confirms correct performance of the test. -
If a control line does not appear the test is invalid, and should be repeated using another dipstick.
-
The intensities of the test lines may vary considerably. Please note that the second and the third line never become as intense as the first line.
-
Sometimes erythrocytes may cause red coloring in the lower part of the result area. This is normal and does not have an effect on the performance of the test.
-
If the test result cannot be interpreted clearly (e.g. if the lines are blotched or uneven) it is recommended that the test be repeated.
-
The result of a test should be interpreted only after 5 minutes have elapsed.
However, do not pay attention to any lines appearing after 5 minutes. -
As with all diagnostic tests, results must be interpreted in the light of other clinical findings.
-
All biological specimens and materials must be treated as potentially hazardous, and disposed of in accordance with local authority guidelines.
Principle of the test
CRP is an acute-phase protein produced rapidly in response to inflammation, infection and tissue damage. It is used in particular to differentiate bacterial infections from virus infections. The test is based on immunochromatography. It involves monoclonal antibodies to human CRP. One is bound to blue latex particles (the detecting label). In the carrier membrane there are three CRP specific antibody zones, to which the blue latex particles will bind if the sample contains CRP. When the dip area of the dipstick is placed in a diluted sample, the dipstick absorbs liquid, which starts to flow up the dipstick. If the sample contains CRP it binds to the antibody labeled with latex particles. The particles are carried by the liquid flow and, if CRP is bound to them, they bind to the catching antibody zones. The more CRP the sample contains the more blue lines become visible.
The red control line confirms the correct performance of the test.
Performance of the test
Analytical sensitivity and measuring range
The lowest detection amount of CRP in serum samples is 10 mg/l. One blue line
appears when the concentration is > 10 mg/l. The second blue line appears when
serum CRP concentration is > 40 mg/l and the third line becomes visible if
the serum CRP concentration > 80 mg/l. Hook effect has been tested with
CRPspiked samples. Samples containing up to 750 mg/l give consistently the
result > 80 mg/l. CRP test is traceable to the reference material ERM-DA470.
Repeatability and reproducibility
Intra- (repeatability) and inter- (reproducibility) assay precision studies
have confirmed that the three different cut-off values of the CRP test are
approximately 10, 40 and 80 mg/l.
Interference testing
No interferences of bilirubin, rheumatoid factor (RF), lipid and SAP (Serum
Amyloid P) have been observed.
Diagnostic performance
Actim CRP test was evaluated at three different hospitals in Finland. At
hospitals 1 and 2 EDTA blood samples were tested against a quantitative
method. The evaluations showed that the Actim CRP results are comparable to
the quantitative measurement. Results are shown in FIG 1 and 2 on the inner
back cover. At hospital 3 Actim CRP test was performed from fingertip blood
and EDTA blood samples. The evaluation showed that the Actim CRP results are
comparable to the quantitative measurement. Results are shown in FIG 3 and 4
on the inner back cover.
Dimension Overall
EVALUATION OF ACTIM CRP TEST Actim CRP vs quantitative CRP
FIG 1.
EVALUATION OF ACTIM CRP TEST Actim CRP vs quantitative CRP
FIG 2.
EVALUATION OF ACTIM CRP TEST Actim CRP vs quantitative CRP
FIG 3.
EVALUATION OF ACTIM CRP TEST Actim CRP vs quantitative CRP
FIG 4.
Explanation of symbols
| Use By
---|---
| Temperature limitation
| Manufacturer
| Batch code
| Specimen dilution buffer
| Contains sufficient for tests
| In Vitro Diagnostic Medical Device
| Consult instructions for use
| Catalogue number
| Single use
Support
Actim Oy
Klovinpellontie 3, FI-02180 Espoo, Finland
Tel. +358 9 547 680
www.medixbiochemica.com
medix@medixbiochemica.com
© Actim Oy. All rights reserved.
Actim is a trademark of Actim Oy.
AOACE31031-1 2019-04-25
