Heartworm

We recommend EDTA or heparin for whole blood collection, however you can also use citrate. If results are doubtful, please use serum.

The assay diluent is specific to our test. We do not recommend the use of any other solution as we cannot guarantee that the product will work properly.

Any positive result should be confirmed prior to initiating heartworm treatment. A confirmatory test should use a different antigen detection method as the original screening test, thus we recommend a Knot test for detection of microfilariae and a well-ELISA.

The following situations may cause this situation:

• Animal could have adult worms that die and be left with circulating microfilariae
• Microfilariae could be Dipetalonema reconditum, a parasite which does not produce the immitis antigen that our test detects.
• Young dogs born to heartworm-positive mothers could be infected transplacentally and be born with circulating microfilariae, but not have adult immitis, therefore no detectable D. immitis antigen.
• Occasionally, microfilariae will be present before detectable levels of antigen have accumulated.

A false positive (or negative) result from an individual animal not resulting from technique errors will continue to occur on multiple tests of the same type. Therefore, the false result is usually caused by some unique characteristics of the particular animal, as opposed to a defective test. This characteristic could be a component of the animal’s blood, which is able to react in a test’s system to show a positive result in the absence of heartworm antigens or a negative result in the presence of heartworm antigens.