Page 16 - Problem-Based Feline Medicine

8 PART 1 CAT WITH UPPER RESPIRATORY TRACT SIGNS

Signs in newborn kittens include continuous crying, Differential diagnoses
nasal discharge, sneezing and dyspnea.
Calicivirus usually has milder upper respiratory signs;
Signs are worse in: oral ulcers are classical; no keratitis or corneal ulcera-
● Young kittens once maternal antibody levels tion; occasionally viral pneumonia occurs.
decrease.
Chlamydophila generally has milder signs, although
● Conditions of crowding, e.g. animal shelters,
young kittens can have severe conjunctivitis and ocu-
breeding colonies and pet shops.
lar-nasal discharge; typically conjunctivitis lasts longer
● Stress factors or other intercurrent disease, e.g.
(weeks) with Chlamydophila.
FIV, FeLV, renal failure.
Cryptococcosis or nasal tumors may occasionally
Signs of rhinotracheitis usually resolve in 2 weeks,
present with an acute onset of sneezing; however, signs
but purulent rhinitis and sinusitis may persist longer.
do not resolve, but become chronic and progressive.
Superficial ulcerative dermatitis occasionally
Concurrent FeLV or FIV should be suspected in cats
occurs on the face, trunk and footpads. The lesions are
with very severe, prolonged signs, or in adult vacci-
usually more severe on the face and occur on the nasal
nated cats with severe signs, and in cats with recurrent
planum or haired skin. They consist of vesicles, ulcers
upper respiratory disease.
and crusts, and may be pruritic. Upper respiratory
tract signs may or may not be present, and signs See page 1213 for more details of differential diagnoses
appear to occur in situations of reactivation of latent in The Cat With Ocular Discharge or Changed
infection. Conjunctival Appearance.
Stomatitis may be associated with latent herpesvirus
infection, and may or may not occur with dermatitis. Treatment
Minimize hospital contamination. Cats should be
Diagnosis treated as outpatients, unless dehydrated or requiring
oxygen.
A definitive diagnosis is usually not made, and a pre-
sumptive diagnosis is based on clinical signs. Use broad-spectrum antibiotics if nasal discharge is
mucopurulent, indicating secondary bacterial infection.
The following diagnostic tests are offered by some lab-
● Antibiotics also help prevent chronic rhinitis.
oratories: fluorescent antibody staining of conjuncti-
● Amoxicillin, cephalosporin, doxycycline or
val or nasal mucosal scrapings or biopsy, antibody
trimethaprim-sulfadiazine are indicated.
titers (measured initially and after convalescence),
● Doxycycline is useful if concurrent infections
virus isolation or polymerase chain reaction (PCR).
of Chlamydophila, Mycoplasma or Bordetella are
● These are infrequently performed for individual
suspected.
cats with signs of upper respiratory tract disease,
because the result rarely changes the treatment. Correct dehydration and maintain optimum hydration
● Obtaining a definitive diagnosis is more useful if a using subcutaneous or intravenous fluids.
cattery problem persists despite vaccination. ● Dehydration is common, because cats will not eat
● Diagnostic tests are indicated to confirm her- or drink, and marked fluid loss may occur from the
pesvirus infection if corneal ulceration is poorly ocular-nasal discharge and salivation.
responsive to treatment, but false-negative results
Improve airflow through the respiratory tract.
are common.
● Clean crusted discharge from the nose three times
Histopathological examination of the skin lesions daily.
indicates ulcerative dermatitis with epithelial cell ● Use a protective agent such as vaseline on the nose
necrosis and eosinophilic inflammation. Epidermal to prevent excoriation.
cells may contain basophilic intranuclear inclusion ● Use a vaporizer or nebulizer to provide airway
bodies. PCR indicates the presence of herpesvirus in humidification, or have the owners put the cat in a
skin samples. steamy bathroom.