Page 53 - Problem-Based Feline Medicine

4 – THE CAT WITH STRIDOR OR STERTOR 45

pression caused by an extraluminal mass. It has Weight loss and avoidance of neck collars can be very
been reported associated with proximal tracheal beneficial in affected cats.
obstructions from a trachael granuloma or polyp.
The cough is often harsh, non-productive and parox- LARYNGEAL EOSINOPHILIC GRANULOMA
ysmal, ending in a gagging episode which may appear
to be productive. Classical signs

Cervical trachea collapse produces inspiratory dysp- ● Stridor from laryngeal region.
nea, while intrathoracic tracheal or bronchial collapse ● Swollen, edematous arytenoid cartilages
will lead to mostly expiratory dyspnea. Stridor is of larynx.
occasionally reported.

Clinical signs
Diagnosis
Syndrome often occurs weeks or months after signs of
Radiographs may show attenuation of the tracheal or
viral upper respiratory tract infection.
bronchial lumina. Fluoroscopy may be more sensitive
for dynamic collapse. Stridor from laryngeal region is evident.
Tracheobronchoscopy is valuable in both diagnosing The larynx appears edematous and swollen.
and grading the severity of the collapse.
With stress, cats become dyspneic and may mouth
breathe.
Differential diagnosis

Tracheitis from feline rhinotracheitis virus is generally Diagnosis
associated with other upper respiratory signs.
Visual appearance and biopsy are diagnostic.
Laryngeal paralysis or edema, tracheal foreign body Biopsy reveals an eosinophilic granuloma.
and tracheobronchial neoplasm can be differentiated
endoscopically.
Differential diagnosis
Small airway disease (feline asthma/bronchitis com-
Invasive squamous cell carcinoma may have a similar
plex) can worsen upper airway collapse, but generally
appearance but can be differentiated on biopsy.
diagnosis is based on the radiographic peribronchiolar
pattern and airway inflammation on lung wash cytology. Other inflammatory infiltrations of the larynx, for
example with lymphocyte, may appear similar, but are
Treatment differentiated on biopsy.

Medical treatment is indicated for a short and mini-
mally attenuated collapsing segment, and consists pri- Treatment
marily of antitussive therapy (butorphanol 1 mg/cat PO
Oral steroids such as prednisolone 2 mg/kg bid PO for
q 6–12 h as needed).
10 days, then taper dose.
Surgical therapy may be indicated with severe col-
If oral medication cannot be given, methylprednisolone
lapse due to trauma. This generally requires referral to
acetate (2–4 mg/kg 7 days for 2–6 treatments), can be
a specialist with experience in airway surgery.
used.
Extraluminal spiral ring prostheses made from a 3 ml
syringe case were successful in reducing signs in two Occasionally, refractory cases need chlorambucil
cats. (0.1–0.2 mg/kg q 24 h initially PO, IM, then q 48 h).