Page 295 - Small Animal Internal Medicine, 6th Edition

CHAPTER 15 Disorders of the Nasal Cavity 267

inflammatory response to irritants or normal nasal flora. BOX 15.1
Preliminary studies have failed to show an association with
VetBooks.ir feline chronic rhinosinusitis and Bartonella infection, based Management Considerations for Cats With Idiopathic
on serum antibody titers or PCR of nasal tissue (Berryessa
Chronic Rhinosinusitis
et al., 2008). In the absence of a known cause, this disease
will be denoted by the term idiopathic feline chronic Facilitate Drainage of Discharge
rhinosinusitis. Vaporizer treatments
Topical saline administration
Clinical Features and Diagnosis Nasal cavity flushes under anesthesia
Chronic mucoid or mucopurulent nasal discharge is the Topical decongestants
most common clinical sign of idiopathic feline chronic rhi- Decrease Irritants in the Environment
nosinusitis. The discharge is typically bilateral. Fresh blood Improvement of indoor air quality
may be seen in the discharge of some cats but is not usually
a primary complaint. Sneezing may occur. Given that this is Control Secondary Bacterial Infections
an idiopathic disease, the lack of specific findings is impor- Long-term antibiotic treatment
tant. Cats should have no funduscopic lesions, no lymph-
adenopathy, no facial or palate deformities, and healthy teeth Treat Possible Mycoplasma Infection
and gums. Anorexia and weight loss are rarely reported. Antibiotic treatment
Thorough diagnostic testing is indicated, as described in Treat Possible Herpesvirus Infection
Chapters 13 and 14. Results of such testing do not support
the diagnosis of a specific disease. Usual nonspecific findings Lysine treatment
include turbinate erosion, mucosal inflammation, and Reduce inflammation
increased mucus accumulation as assessed by nasal imaging Second-generation antihistamine treatment
and rhinoscopy; neutrophilic or mixed inflammation with Oral prednisolone treatment
bacteria on cytology of nasal discharge; and neutrophilic Other unproven treatments with possible antiinflammatory
and/or lymphoplasmacytic inflammation on nasal biopsy. effects
Nonspecific abnormalities attributable to chronic inflamma- Azithromycin
tion, such as epithelial hyperplasia and fibrosis, may also be Piroxicam
seen. Secondary bacterial rhinitis or Mycoplasma infection Leukotriene inhibitors
may be identified. Omega-3 fatty acids
Treatment Provide Surgical Intervention
Cats with idiopathic chronic rhinosinusitis often require Turbinectomy
Frontal sinus ablation
management for years. Fortunately, most of these cats are
healthy in all other respects. Treatment strategies include
facilitating drainage of discharge; decreasing irritants in the
environment; controlling secondary bacterial infections;
treating possible Mycoplasma or FHV infection; reducing avoided. Motivated clients can take steps to improve the air
inflammation; and, as a last resort, performing a turbinec- quality in their homes, such as by cleaning carpet, furniture,
tomy and frontal sinus ablation (Box 15.1). drapery, and furnace; regularly replacing air filters; and using
Keeping secretions moist, performing intermittent nasal an air cleaner. The American Lung Association has a useful
flushes, and judiciously using topical decongestants facilitate Web site with nonproprietary recommendations for improv-
drainage. Keeping the cat in a room with a vaporizer, for ing indoor air quality (www.lung.org).
instance, during the night can provide symptomatic relief by Long-term antibiotic therapy may be required to manage
keeping secretions moist. Alternatively, drops of sterile saline secondary bacterial infections. Broad-spectrum oral antibi-
can be placed into the nares. Some cats experience a marked otics such as amoxicillin (22 mg/kg q8-12h) are often suc-
improvement in clinical signs for weeks after flushing of cessful. Doxycycline (5 mg/kg q12h or 10 mg/kg q24h,
the nasal cavity with copious amounts of saline. General followed by a bolus of water) has activity against some bac-
anesthesia is required, and the lower airways must be pro- teria and Chlamydophila and Mycoplasma organisms and
tected with an endotracheal tube, gauze sponges, and posi- can be effective in some cats when other drugs have failed.
tioning of the head to facilitate drainage from the external Azithromycin (5-10 mg/kg q12h for 1 day, then every 3 days)
nares. Topical decongestants, as described for feline URI, can be prescribed for cats that are difficult to medicate. This
may provide symptomatic relief during episodes of severe author reserves fluoroquinolones for cats with documented
congestion. resistant gram-negative infections that have failed other
Irritants in the environment can further exacerbate treatment attempts. If a beneficial response to antibiotic
mucosal inflammation. Irritants such as smoke (from therapy is seen within 1 week of its initiation, the antibiotic
tobacco or fireplace) and perfumed products should be should be continued for at least 4 to 6 weeks. If a beneficial