Page 20 - Problem-Based Feline Medicine

12 PART 1 CAT WITH UPPER RESPIRATORY TRACT SIGNS

been attributed to vasculitis and disseminated tularensis (tularemia), all may be difficult to differen-
intravascular coagulation (DIC). tiate pre-mortem if the illness progresses rapidly to
● Some cats also had pneumonia, pleural effusion, death.
pancreatitis and abdominal effusion.
Pancreatitis does not usually produce such a high fever
as FCV-Ari.
Diagnosis
Treatment
Presumptive diagnosis of calicivirus infection is based
on clinical signs Treatment for calicivirus infection including the hem-
orrhagic form involves supportive therapy (see treat-
A definitive diagnosis is usually not made except where
ment of herpesvirus for details, page 8).
there is an ongoing cattery problem, and is based on
● Maintain good hydration.
demonstrating a rising antibody titer, or on PCR or
● Humidify airways using a vaporizer or nebulizer.
viral isolation. These tests are available through some
● Use broad-spectrum antibiotics for secondary
laboratories.
infections.
Identification of FCV-Ari is based on the clinical syn- ● Clean discharges from face.
drome, pathology and culture of virus from blood, ● Provide oxygen if dyspneic.
nasal or ocular discharge, spleen or lungs. ● Analgesics (e.g. buprenorphine) may help make the
Thrombocytopenia and prolonged PT and aPTT may be cat more comfortable if there is severe ulceration.
evident in some cats.
No specific therapy is available, and no antiviral
drug is effective.
Differential diagnosis
Prognosis
Herpesvirus generally has more pronounced ocular-
nasal discharge and paroxysms of sneezing. Corneal Signs generally resolve within 5–7 days.
lesions in herpesvirus infection are usually diagnostic,
Rarely, mortality is high with strains causing severe
and mouth ulcers rarely occur.
viral pneumonia or vasculitis (FCV-Ari), and kittens
Mycoplasma often occurs as a secondary infection may die suddenly.
in viral upper respiratory tract disease, rather than a
Chronic gingivitis and stomatitis occurs in some carriers.
primary disease, and is not associated with mouth
ulcers. Persistent mild conjunctivitis or ulcerative keratitis
may be a problem.
Chlamydia generally has mild upper respiratory tract
signs, but no mouth ulcers; conjunctivitis often persists
longer and is more severe than with calicivirus. Transmission

Caustic stomatitis generally does not cause fever. Calicivirus is highly contagious, with nearly 100%
Ocular-nasal discharge is usually absent, or if present, morbidity in susceptible cats.
is a mild, serous discharge.
Infection spreads rapidly when multiple cats are housed
Concurrent infection with herpesvirus, mycoplasma together.
or Bordetella may confuse the clinical picture. ● Young unvaccinated kittens 2–6 months of age are
most susceptible.
Acetaminophen (paracetamol) toxicity produces simi-
lar facial and paw swelling in an acutely ill cat as does Incubation period is 2–4 days. First signs generally
FCV-Ari, but cats are not febrile. occur 3 days after exposure, but this varies with dose
and virulence of virus.
Other acute infectious illnesses may appear similar
to FCV-Ari, for example Yersinia pestis (feline Transmission is primarily via direct contact with
plague), Salmonella spp. (song-bird fever), Francisella infected cats.