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SNAP Canine Heartworm Antigen Test Kit
This page contains information on SNAP Canine Heartworm Antigen Test Kit for veterinary use.The information provided typically includes the following:
- SNAP Canine Heartworm Antigen Test Kit Indications
- Warnings and cautions for SNAP Canine Heartworm Antigen Test Kit
- Direction and dosage information for SNAP Canine Heartworm Antigen Test Kit
SNAP Canine Heartworm Antigen Test Kit
This treatment applies to the following species:Canine Heartworm Antigen Test Kit
For veterinary use only.
SNAP* HTWM
In-vitro diagnostic for the semiquantitative detection of Dirofilaria immitis (D. immitis) antigen in canine and feline whole blood, serum or plasma. The SNAP test is an enzyme immunoassay: after conjugate and test sample are mixed and added to the sample well, the device is then activated, releasing reagents stored within the device. Color development in the antigen indicator spots is proportional to the antigen concentration in the sample.
Precautions and warnings
● During manufacturing, the bioactive spots are dyed for quality-control purposes. This does not interfere with the test results or interpretation.
● All wastes should be properly decontaminated prior to disposal.
● Do not mix components from kits with different serial numbers.
● WARNING: Conjugate - H316/P332+P313/EUH208. Causes mild skin irritation. If skin irritation occurs: Get medical advice/attention. Contains Proclin. May produce an allergic reaction.
Storage
● Store at 2-25°C until expiration date.
● All components must be at room temperature (18-25°C) before running the test.
Kit components
Item |
Reagents |
Quantity |
1 |
1 bottle anti-HTWM: HRPO conjugate (Preserved with gentamicin and Proclin) |
7.0 mL |
2 |
SNAP Device |
15 or 30 |
Reagents contained in each device: |
||
|
Wash Solution (preserved with Proclin) |
0.4 mL |
|
Substrate Solution |
0.6 mL |
Other Components: transfer pipettes, sample tubes, and reagent rack |
Sample information
● Samples must be at room temperature (18-25°C) before beginning test procedure.
● Serum, plasma or anticoagulated whole blood (e.g., EDTA, heparin), either fresh or stored at 2-8°C for up to one week, can be used.
● For longer storage, serum or plasma can be frozen (-20°C or colder) and then recentrifuged before use.
● Hemolyzed or lipemic samples will not affect test results.
Test procedure
1. If stored in a refrigerator, allow all components to equilibrate at room temperature (18-25°C) for 30 minutes. Do not heat.
2. Using the pipette that is provided, dispense 3 drops of sample into a new sample tube.

3. Holding the bottle vertical, add 4 drops of conjugate to the sample tube.

4. Cap the sample tube and mix it thoroughly by inverting it 3-5 times.

5. Place the device on a horizontal surface. Add the entire contents of the sample tube to the sample well, being careful not to splash the contents outside of the sample well.
The sample will flow across the result window, reaching the activation circle in 30-60 seconds. Some sample may remain in the sample well.

6. When color FIRST appears in the activation circle, push the activator firmly until it is flush with the device body.
Note: Some samples may not flow to the activation circle within 60 seconds, and, therefore, the circle may not turn color. In this case, press the activator after the sample has flowed across the result window.

7. Read test result at eight minutes.
Interpreting Test Results
Positive Result
Any amount of color development in the sample spots indicates a positive result and color intensity is proportional to the heartworm antigen concentration in the sample.

Low antigen levels

High antigen levels

Negative Result
Only the positive control spot develops color.

Invalid results
1. Negative Control (safeguard against false positives) - If color in the negative control spot is equal to or darker than the color in the sample spots, the result is invalid and the sample should be retested.

2. No Color Development - If the positive control does not develop color, repeat the test.
3. Background - If the sample is allowed to flow past the activate circle, background color may result. Some background color is normal. However, if colored background obscures test result, repeat the test.
Idexx Snapshot Dx* Analyzer
Test results can also be read using the SNAPshot Dx Analyzer. A complete description of how to enter patient data and read test results using the SNAPshot Dx Analyzer can be found in the SNAPshot Dx Analyzer Operator’s Guide.
Sensitivity and specificity
Comparison test |
Sample size |
Sample type |
Relative sensitivity and specificity |
Kappa Statistic |
||||
+/+ |
-/+ |
+/- |
-/- |
Total |
||||
PetChek* Heartworm |
152 |
3 |
0 |
103 |
258 |
Serum/Plasma/Whole Blood |
Sen., 98% (95% CL 94%-100%) |
0.98 |
The heartworm sensitivity values in this table were generated from a mixed worm-burden population. Sensitivity for samples from dogs with very low wormburdens (≤2 worms, n=24) was 91.7%; sensitivity when testing samples from dogs with >2 worms was 99.2%.
Sensitivity and specificity are based on visual interpretation of SNAP results.
CL = confidence limit
Symbol descriptions

IDEXX Technical Support
USA/Canada: 1 800 248 2483 • idexx.com
Australia: 1300 44 33 99 • idexx.com.au
Europe: idexx.eu
U.S. Vet. License No. 313
Product Code: 5018.03
*SNAP, SNAPshot Dx and PetChek are trademarks or a registered trademarks of IDEXX Laboratories, Inc. or its affiliates in the United States and/or other countries.
Patent information: idexx.com/patents.
© 2018 IDEXX Laboratories, Inc. All rights reserved.
IDEXX, One IDEXX Drive, Westbrook, Maine 04092 USA
idexx.com
06-04367-12
CPN: 1116046.12
ONE IDEXX DRIVE, WESTBROOK, ME, 04092
Telephone: | 207-556-0300 | |
Fax: | 207-556-4346 | |
Pet Diagnostics/Order Desk: | 800-248-2483 | |
Poultry/Livestock Diagnostics: | 800-548-9997 | |
Poultry/Livestock Order Desk: | 800-943-3999 | |
Website: | www.idexx.com | |
Email: | lpdweb@idexx.com |
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Every effort has been made to ensure the accuracy of the SNAP Canine Heartworm Antigen Test Kit information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the US product label or package insert. |
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