Page 397 - Problem-Based Feline Medicine

19 – THE PYREXIC CAT 389

used in cats with severe pulmonary signs, although Demonstration of the organism in erythrocytes
the cost is higher. Dose at 2–3 mg/kg IV 3 days per (merozoite stage) is possible only relatively late in
week for a total of 9–12 treatments (cumulative dose the disease, approximately 1–3 days before death.
of 24–27 mg). Dilute to a concentration of 1 mg/ml in Parasitemic cats usually have only 1–2% of RBCs
dextrose 5% and infuse over 1–2 hours. affected, and up to 50% of cats have parasitemias that
are very low or undetectable.
CYTAUXZOON FELIS Demonstration of the organism in macrophages from
bone marrow, spleen, liver or lymph node aspirates
Classical signs may be possible even when organisms are not evident
in blood.
● Fever.
● Anorexia. Serum antibody levels and direct FA test for detec-
● Dyspnea. tion of tissue phase are available through some labs.
● Pale mucous membranes.
● Icterus.
● Collapse. HYPERTHYROIDISM

See main reference on page 534 for details (The Anemic Classical signs
Cat).
● Weight loss.
● Polyphagia.
Clinical signs ● Polyuria/polydipsia.
● Behavioral changes.
Primarily found in the south-central and southeast
● Unkempt appearance.
United States. The North American bobcat is the natu-
● Mild elevations in temperature.
ral host.
There is usually a history of exposure to ticks in the See main reference on page 304 for details (The Cat
previous 5–20 days (incubation period is 5–20 days). With Weight Loss and a Good Appetite).
The clinical course of disease is approximately 1 week
and often ends in death.
Clinical signs
Clinical signs are the result of an overwhelming
Weight loss in spite of normal to increased appetite.
hemolytic crisis.
Polyuria/polydipsia.
Rapid onset of fever, dyspnea, anorexia, pale mucous
membranes, icterus and dark-colored urine are typical. Behavioral changes which often include hyperactivity
and aggression.
Collapse and death occur 2–3 days after the fever
peak. Hypothermia occurs in the terminal stages. Unkempt, rough hair coat and sometimes overgrown
nails.
There appear to be non-pathogenic strains as well.
Tachycardia accompanied by a “gallop” rhythm and/or
a systolic murmur.
Diagnosis
Mild fever which may be intermittent in nature and
A complete blood count reveals regenerative anemia,
reflect the increased metabolic rate in this disease.
hemoglobinemia and neutrophilia or neutropenia.
These cats are easily stressed and may present dyspneic
The biochemistry panel commonly has hyperbiliru- and tachycardic with a mildly elevated temperature,
binemia. usually not greater than 39.4˚C (103.0˚F).

Urinalysis may show evidence of hemoglobin and Enlarged thyroid glands are often evident on palpation
bilirubin. of the neck.