Page 390 - Problem-Based Feline Medicine

382 PART 7 SICK CAT WITH SPECIFIC SIGNS

Mild to moderate fever can be seen in the acute Parvoviral antigen can be detected in feces using the
phase. canine parvoviral antigen tests or electron microscopy.
Pneumonia is rarely associated with this infection. Histopathologic changes include denuded intestinal
crypts and blunted villi (often a post-mortem diagnosis).
Diagnosis
FRANCISELLA TULARENSIS
History and clinical signs are highly suggestive.
(TULAREMIA)*
Cytology of conjunctival scrapings reveal dark blue
inclusion bodies (Giemsa stain). Classical signs
Immunofluorescent antibody staining or polymerase ● Fever.
chain reaction assay to demonstrate the organism ● Anorexia.
in conjunctival scrapings is available from some laborato- ● Lethargy.
ries. ● Lymphadenopathy.
● Oral ulcers.
PANLEUKOPENIA* ● Icterus.

Classical signs
Pathogenesis
● Acute onset of depression.
● Acute onset of vomiting. Francisella tularensis is a Gram-negative coccobacil-
● Diarrhea usually 1–2 days later. lus. Clinical signs are associated with Gram-negative
● Dehydration. endotoxins and bacteremia.
● Fever or hypothermia.
There are two main strains of the organism, both of
● In utero infection can result in cerebellar
which have been isolated from cats.
signs.
Type A strain is:
See main reference on page 722 for details (The Cat ● Associated with tick–rabbit cycle.
With Signs of Acute Small Bowel Diarrhea). ● Found only in North America.
● Highly virulent for laboratory rabbits.
Clinical signs ● Associated with more severe disease in humans.
Rapid onset of depression, anorexia, and vomiting Type B strain is:
especially in peracute and acute disease. Fetid diarrhea ● Associated with a more complex cycle involving
(may be hemorrhagic) typically follows 1–2 days after rodents, ticks, mosquitoes, mud and water.
initial onset of signs. ● Found throughout the northern hemisphere.
● Avirulent for laboratory rabbits.
Severe dehydration and electrolyte abnormalities.

Initial fever followed by hypothermia as the disease
progresses. Clinical signs
High mortality rate when signs are severe. History of contact with rabbits, especially if the cat is
a hunter.
Diagnosis Any age of cat can be infected, but younger cats are
more susceptible to developing septicemia.
The disease should be suspected in cats less than one
year of age with no history of vaccination and a rapid The spectrum of illness varies from severely affected
clinical course. to asymptomatic.
Panleukopenia evident on hematology. Fever is generally > 40˚C (104˚F).