Page 22 - Problem-Based Feline Medicine

14 PART 1 CAT WITH UPPER RESPIRATORY TRACT SIGNS

Treatment Clinical signs

Use tetracycline ophthalmic ointment. Continue for Conjunctivitis is initially unilateral, progressing to
10 days after clinical remission (usually 2–4 weeks of bilateral involvement.
treatment 3–4 times daily). Avoid use of bacitracin- ● Conjunctiva may be normal, hyperemic or edema-
neomycin-polymyxin ointment because of reports of tous.
acute death associated with its use. ● In severe infections, conjunctiva may be covered in
a gray pseudomembrane (diptheritic membrane).
Oral doxycycline therapy may also be required in
resistant cases. It is excreted in tears, and is also effec- Nasal discharge is mild, and results from ocular dis-
tive as a sole agent. Treat for 21 days, although up to 6–8 charge draining into the nose.
weeks treatment may be required in refractory cases.
Oral azithromycin (Zithromax, Pfizer, 5 mg/kg q 24 h Diagnosis
PO for 14 days) is an alternative treatment to tetracy- Diagnosis is based on visualization of clusters of coc-
cline. coid or coccobacillary organisms in the periphery of
Some chronic cases may require long-term systemic epithelium cells from stained (e.g. Diff-Quik stain)
therapy. conjunctival scrapings.
Isolation of the organism can be done in most labora-
Prognosis tories from clean conjunctival swabs. Remove ocular
discharges with sterile normal saline solution prior to
Chlamydophilosis frequently progresses to chronic taking the sample, to reduce contamination from sec-
signs, with conjunctival thickening and prominent con- ondary bacterial infections.
junctival lymphoid follicles.
Untreated cats frequently relapse after apparent recovery. Differential diagnosis

Chlamydophila has similar clinical signs, but is more
Transmission common.
Transmission is by direct contact with an infected cat.
Treatment

Chloramphenicol or doxycycline ophthalmic oint-
MYCOPLASMA ment (6 mm (1/4 inch) strip q 6 h).

Classical signs
BORDETELLA
● Conjunctivitis with purulent ocular
discharge; unilateral progressing to Classical signs
bilateral.
● Pyrexia.
● Sneezing and nasal discharge.
See main reference on page 1218 for details (The Cat
● Mandibular lymphadenopathy.
With Ocular Discharge or Changed Conjunctival
● Coughing.
Appearance).
● Dyspnea, cyanosis, pneumonia.
Pathogenesis
Pathogenesis
Causal agents are Mycoplasma felis and M. gatae.
Bordetella bronchiseptica may act as a primary
Mycoplama more often plays a secondary role to pathogen, or play a secondary role to herpesvirus or
herpesvirus or calicivirus infections. calicivirus infection.