Changes

In both dogs and cats, routine haematology, biochemistry and urinalysis should be performed. Most parameters are usually within normal limits, but an anaemia can often be seen. Eosinophilia and basophilia are also common, and when seen together suggests occult dirofilariasis or allergic lung disease ^{1, 3}. Eosinophilia peaks as L5 enter the pulmonary arteries and subsequently varies. An inflammatory leukogram is also possible³. Hyperglobulinemia due to antigenic stimulation is an inconsistent finding^{1, 3}. Right-sided heart failure or immune-complex glomerulonephritis can lead to hypoalbuminaemia and, very occasionally, nephrotic syndrome¹. Because of this, it is possible for urinalysis to reveal proteiunuria^{1, 3}. Haemoglobinaemia and haemoglobinuria are associated with caval syndrome³.  

In both dogs and cats, routine haematology, biochemistry and urinalysis should be performed. Most parameters are usually within normal limits, but an anaemia can often be seen. Eosinophilia and basophilia are also common, and when seen together suggests occult dirofilariasis or allergic lung disease ^{1, 3}. Eosinophilia peaks as L5 enter the pulmonary arteries and subsequently varies. An inflammatory leukogram is also possible³. Hyperglobulinemia due to antigenic stimulation is an inconsistent finding^{1, 3}. Right-sided heart failure or immune-complex glomerulonephritis can lead to hypoalbuminaemia and, very occasionally, nephrotic syndrome¹. Because of this, it is possible for urinalysis to reveal proteiunuria^{1, 3}. Haemoglobinaemia and haemoglobinuria are associated with caval syndrome³.  

There are several methods for the specific demonstration of ''Dirofilaria immitis'' in the animal. Firstly, direct microscopic examination allows rapid identification microfilariae in a drop of fresh blood as their movements can vigorously displace the surrounding red blood cells². Despite being quick, simple and inexpensive, this test is not sufficiently sensitive to provide a definitive diagnosis, particularly when there is a low concentration of microfilariae in the bloodstream. Filtration methods therefore exist to facilitate the microscopic demonstration of microfilariae. These include the modified Knott's test, which involves haemolysis, centrifugation and staining with methylene blue before direct examination. Tests such as this are more

There are several methods for the specific demonstration of ''Dirofilaria immitis'' in the animal. Firstly, direct microscopic examination allows rapid identification microfilariae in a drop of fresh blood as their movements can vigorously displace the surrounding red blood cells². Despite being quick, simple and inexpensive, this test is not sufficiently sensitive to provide a definitive diagnosis, particularly when there is a low concentration of microfilariae in the bloodstream. Filtration methods therefore exist to facilitate the microscopic demonstration of microfilariae^{2, 3}. These include the modified Knott's test, which involves haemolysis, centrifugation and staining with methylene blue before direct examination. Tests such as this are more sensitive than merely examining a drop of blood, and the morphology of microfilariae can be clearly seen. Sensitivity in comparison to other methos is still, however, low and so microfilarial identification tests are often reserved for confirmation of weak positive antigen tests and determination of microfilarial status prior to treatment with a microfilaricide³. Cats frequently lack circulating microfilariae, and so direct micrscopic examination is of little use in this species.

sensitive than merely examining a drop of blood, and the morphology of microfilariae can be clearly seen. However, cats frequently lack circulating microfilariae, and so direct micrscopic examination is of little use in this species.

Antigen tests

Antigen tests