Page 268 - Small Animal Internal Medicine, 6th Edition

PART TWO Respiratory System Disorders
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PART II Respiratory System Disorders
Eleanor C. Hawkins

VetBooks.ir CHAPTER 13

Clinical Manifestations of

Nasal Disease

GENERAL CONSIDERATIONS widespread. Awns can enter the body through any orifice,
even through intact skin; the external nares are one common
The nasal cavity and paranasal sinuses have a complex route.
anatomy and are lined by mucosa. Their rostral portion is
inhabited by bacteria in health. Nasal disorders are fre-
quently associated with mucosal edema, inflammation, and NASAL DISCHARGE
secondary bacterial infection. They are often focal or multi-
focal in distribution. These factors combine to make the Classification and Etiology
accurate diagnosis of nasal disease a challenge that can be Nasal discharge is most commonly associated with disease
met only through a thorough, systematic approach. localized solely within the nasal cavity and paranasal sinuses,
Diseases of the nasal cavity and paranasal sinuses typi- although it may also develop with disorders of the lower
cally cause nasal discharge, congestion, sneezing, or stertor respiratory tract, such as bacterial pneumonia and infectious
(i.e., snoring or snorting sounds). Less common signs include tracheobronchitis, or with systemic disorders, such as coagu-
facial deformity, systemic signs of illness (e.g., lethargy, inap- lopathies and systemic hypertension. Nasal discharge is
petence, weight loss), or, rarely, central nervous system signs. characterized as serous, mucopurulent with or without hem-
The general diagnostic approach to animals with nasal orrhage, or purely hemorrhagic (epistaxis). Serous nasal dis-
disease is included in the discussion of nasal discharge. Spe- charge has a clear, watery consistency. Depending on the
cific considerations related to sneezing, stertor, and facial quantity and duration of the discharge, a serous discharge
deformity follow. Stenotic nares are discussed in the section may be normal, may be indicative of viral upper respiratory
on brachycephalic airway syndrome (see Chapter 18). infection, or may precede the development of a mucopuru-
Nasal foreign bodies are mentioned throughout the dis- lent discharge. As such, many of the causes of mucopurulent
cussion of nasal disease. Nasal foreign bodies most often discharge can initially cause serous discharge (Box 13.1).
enter the nasal cavity through the external nares, although Mucopurulent nasal discharge typically is characterized
nasal or pharyngeal signs can also be the result of foreign by a thick, ropey consistency and has a white, yellow, or
material taken into the mouth and subsequently coughed green tint. A mucopurulent nasal discharge implies inflam-
into the caudal nasopharynx. Plant material is most often the mation. Most intranasal diseases result in inflammation and
culprit. Blades of grass, grass seeds arranged in heads with secondary bacterial infection, making this nonspecific sign
stiff bristles (grass awns; Fig. 13.1), and thin, stiff leaves (such a common presentation for most nasal diseases. Potential
as those of juniper bushes and cedar trees) have a physical etiologies include infectious agents, foreign bodies, neopla-
design that facilitates movement in one direction. Consider sia, polyps, and extension of disease from the oral cavity
running a blade of grass between your fingertips. Usually the (see Box 13.1). If mucopurulent discharge is present in con-
grass moves smoothly in one direction but resists movement junction with signs of lower respiratory tract disease, such
in the other. Because of this property, attempts to expel the as cough, respiratory distress, or auscultable crackles, the
foreign material by coughing or sneezing often cause the diagnostic emphasis is initially on evaluation of the lower
material to travel more deeply into the body instead. Nasal airways and pulmonary parenchyma. Hemorrhage may be
foreign bodies are particularly common in the western associated with mucopurulent exudate from any etiology,
United States, where “foxtail” grasses (those with awns) are but significant and prolonged bleeding in association with

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