Changes

===Laboratory Tests===

===Laboratory Tests===

* A reliable way to diagnose canine distemper is the demonstration of viral infected cells by immunofluorescence. Examination of conjunctival scrapings and blood smears is useful during early stages of the illness, but false negative results are likely to occur as the disease progresses. Tests are accurate when performed on appropriate necropsy tissues.

 

With the exception of lymphopenia during early infection, routine haematology and biochemistry do not show any typical changes. Serology is also of limited value for several reasons. Firstly, a patient may die before an antibody response is mounted; secondly, a positive antibody titre does not discriminate between infected and vaccinated animals; and thirdly, IgM may remain high for up to three weeks following vaccination and three months after infection. Detection of canine distemper virus antibody in the cerebrospinal fluid is, however, indicative (although not diagnostic) of distemper encephalitis.

    * Clinical specimens: Conjunctival scrapings, blood (buffy coat) smears, lung, urinary bladder, stomach, and brain.

 

There are a number of tests available to confirm the diagnosis of canine distemper. Immunohistochemistry can be used to detect viral antigen in samples of skin, nasal mucosa or footpad epithelium, and viral antigen or inclusions may be demonstrated in buffy coat cells, urine sediment and conjunctival or vaginal imprints. However, negative results do not rule out a diagnosis of distemper. RT-PCR can also be performed on buffy coat, urine sediment, conjuncival swabs or cerebrospinal fluid. A retrospective diagnosis can be made post-mortem on the basis of histopathology, immunofluorescence or immunohistochemistry, virus isolation or RT-PCR. The preferred tissues for these techniques are lung, stomach, urinary bladder, lymph nodes and brain.

 

===Diagnostic Imaging===

===Diagnostic Imaging===