Changes

Firstly, clinical signs should be suggestive of toxoplasmosis, despite variation in the presentation of disease between individuals. Although no pathognomic changes for toxoplasmosis are seen on routine haematology, biochemistry and urinalysis, certain results results are often seen in ''T. gondii'' infection. For example, most cats show a mild non-regenerative anaemia, and 50% of pateients are initially leukopenic due to lymphopenia. Neutropenia may occur in conjunction with lymphopenia, and leukocytosis may occur during recovery³. Most patients also show and increase in creatine kinase, ALT, SAP, and hypoalbuminaemia is also common^{1, 3}. 25% of cats show hyperbilirubinemia and icterus, and pancreatitis may cause low to low normal serum calcium. A mild proteinuria and bilirubinuria are often revealed by urinalysis.

Firstly, clinical signs should be suggestive of toxoplasmosis, despite variation in the presentation of disease between individuals. Although no pathognomic changes for toxoplasmosis are seen on routine haematology, biochemistry and urinalysis, certain results results are often seen in ''T. gondii'' infection. For example, most cats show a mild non-regenerative anaemia, and 50% of pateients are initially leukopenic due to lymphopenia. Neutropenia may occur in conjunction with lymphopenia, and leukocytosis may occur during recovery³. Most patients also show and increase in creatine kinase, ALT, SAP, and hypoalbuminaemia is also common^{1, 3}. 25% of cats show hyperbilirubinemia and icterus, and pancreatitis may cause low to low normal serum calcium. A mild proteinuria and bilirubinuria are often revealed by urinalysis.

* Demonstration of antibodies in serum, aqueous

Demonstration of antibodies in serum, aqueous humour or CSF is indicative of exposure to ''T. gondii'', but does not necessarily show active infection. This could be overcome by testing for ''T. gondii'' antigen or immune complexes, but these methods are currently only available to researchers. Several techniques are commercially available for detection of antibody, including ELISA,

humour or CSF (documents exposure to T gondii);

immunofluorescent antibody testing, western blot immunoassay, Sabin-Feldmann dye test, and agglutination tests. Although these tests are theoretically able to detect all classes of immunoglobulin against ''Toxoplasma gondii'' in many species, it seems that feline serum positive for IgM only often reads as a false negative^{7, 8}

T gondii-specific antibodies, antigens and immune

 

(Lappin 1996). Tests for antigens and immune complexes

are currently only available in research laboratories

and so will not be discussed further.

Antibodies can be detected using a range of techniques

that are commercially available, including ELISA,

immunofluorescent antibody, western blot immunoassay,

Sabin-Feldmann dye test, and a variety of agglutination

tests. ELISA, immunofluorescent antibody assay

and western blot immunoassay have been adapted to

detect IgM, IgG and IgA antibody responses (see graph

A latex agglutination assay and an indirect haemagglutination

A latex agglutination assay and an indirect haemagglutination

assay are also available commercially. These

assay are also available commercially. These