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DiroCHEK Kilo Pack

This page contains information on DiroCHEK Kilo Pack for veterinary use.
The information provided typically includes the following:
  • DiroCHEK Kilo Pack Indications
  • Warnings and cautions for DiroCHEK Kilo Pack
  • Direction and dosage information for DiroCHEK Kilo Pack

DiroCHEK Kilo Pack

This treatment applies to the following species:
Manufacturer: Zoetis

Canine Heartworm Antigen Test Kit

For the Detection of Canine and Feline Heartworm Infection


Test Principles

DiroCHEK® is an enzyme-linked immunosorbent assay for the detection of adult Dirofilaria immitis antigen in canine and feline plasma or serum. The reaction wells are coated with antibodies directed against D. immitis antigen. Another antibody is labeled with the enzyme horseradish peroxidase. Any antigen present in the specimen (plasma or serum) is bound by the antibody coated well and the enzyme-linked antibody to form a specific complex. Any free enzyme-linked antibody is washed away and a chromogenic substrate is added. In the absence of D. immitis antigen, no color change will be observed. The development of a blue color specifically indicates the presence of D. immitis antigen.


Anti-D. immitis Coated Wells


Well Holder


Positive Control (Red Cap)

3.5 ml

Negative Control (Gray Cap)

3.5 ml

Reagent 1 - HRP Antibody Conjugate (Blue Cap)

60 ml

Reagent 2 - Chromogenic Substrate Buffer (Purple Cap)

2 x 60 ml

Materials required but not provided:

Precision pipet and tips

Distilled or deionized water

Materials suggested but not provided:

Multi-channel pipet

Reagent basins

Patent No. 4,789,631


1. Prior to use, allow kit to come to room temperature (21°-25°C; 70°-78°F).

2. To prevent contamination, do not return reagent to bottle.

3. Do not mix reagents between different serials.

4. Do not expose kit to direct sunlight.

5. Do not use expired components.

6. Follow instructions carefully.


Storage And Stability

Store the test kit at 2°-7°C (36°-45°F). Do not freeze. Reagents will be stable until the expiration date provided they have been stored properly.

Sample Information

50 µl (0.05 ml) of serum or plasma is required. Serum or plasma (not whole blood) may be stored at 2°-7°C (36°-45°F) for 7 days; -20°C or below if stored longer. Severely hemolyzed and/or lipemic samples may produce background color. When in doubt, obtain a better quality sample.

Predicting Heartworm Burden

Level of color in sample wells will intensify with increasing level of heartworm antigen. Level of heartworm antigen correlates with the number of heartworms present, although it is more closely related to the actual weight of worms present (a product of both the number and size of worms).*

*Courtney CH, Zeng Q, Bean ES. Predicting Heartworm Burdens with the DiroCHEK Heartworm Antigen Test Kit. J Am Anim Hosp Assoc 1989;25:643-646

DiroCHEK® Heartworm Test Procedure

NOTE: Use PLASMA or SERUM samples only (NO WHOLE BLOOD).

Prior to use, allow kit components to come to room temperature (70°-78° F,- 21°-25° C).

Test Procedure

Step 1: Determine required number of antibody coated wells. One well for the Positive Control, 1 well for the Negative Control and 1 well for each sample. Remove required number of plates and/or removable wells. Place removable wells in the well holder, leaving wells attached to each other.

Step 2: Place 1 drop or 0.05 mL of Positive Control into the first well. Place 1 drop or 0.05 mL of Negative Control into the second well. Place 0.05 mL of sample into the next well. Using a separate pipet tip for each sample, place 0.05 mL of each additional sample into subsequent wells.

Step 3: Add 0.05 mL of Reagent 1 (Conjugate) into each well. Tap well holder (without splashing) for 15 seconds to mix.


Step 4: Discard fluid in wells into sink or appropriate container. Invert and blot firmly against a

paper towel.

Step 5: Wash wells vigorously by directing a forceful stream of distilled or deionized water into each well. (Oversplashing will not contaminate adjacent wells.) Shake out residual liquid. Repeat wash at least 5 separate times. Wells cannot be overwashed. Invert and blot against a paper towel to remove final drops of water.

Step 6: Add 0.10 mL of Reagent 2 (Chromogenic Substrate Buffer) to each well. Tap well holder (without splashing) for 15 seconds to mix.

WAIT 5 MINUTES. Read results.

Interpretation Of Results

Controls: For the test to be valid, the Positive Control should be distinctly blue and the Negative Control should be clear.

Samples: Positive samples will be blue. Color intensity will vary with level of heartworm antigen present. This may reflect worm burden. (See PREDICTING HEARTWORM BURDEN.)

Negative samples will be clear.


SYNBIOTICS CORPORATION, 16420 Via Esprillo, San Diego, CA 92127

U.S. Veterinary License Number 312

Licensed under U.S. Pat. No. 4,839,275: Canadian Pat. No. 1,232,849: and Australian Pat. No. 582,129.

DiroCHEK® is a registered trademark of Synbiotics Corporation.

©1995 Synbiotics Corporation


NAC No.: 11150071

Telephone:   269-359-4414
Customer Service:   888-963-8471
Every effort has been made to ensure the accuracy of the DiroCHEK Kilo Pack 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.

Copyright © 2018 North American Compendiums. Updated: 2018-02-26