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Basics ⬇

Outline

BASICS

Overview!!navigator!!

Epiglottiditis is a nonspecific inflammatory disease of the epiglottis.

Signalment!!navigator!!

  • Primarily racehorses (2–10 years) in active race training
  • Occasionally seen in older horses (15–30 years) with inflammatory disease or neoplasia
  • No known breed or sex predilection
  • May be associated with epiglottic abscess or epiglottic chondritis

Signs!!navigator!!

  • Chief complaints—abnormal respiratory tract noise and exercise intolerance
  • Coughing (eating) is fairly common
  • Some horses act mildly pained when swallowing

Causes and Risk Factors!!navigator!!

  • Cause—suspect viral or subepiglottic trauma or surgical trauma
  • Repeated, strenuous exercise may induce inflammatory changes on the subepiglottic mucosal surface
  • Inhaled particulate activities, bacterial or viral infections
  • May be secondary to surgical trauma

Diagnosis ⬆ ⬇

Outline

DIAGNOSIS

Differential Diagnosis!!navigator!!

  • The diagnosis is established based on endoscopy of the upper respiratory tract
  • Occasionally, the endoscopic appearance of a swollen epiglottis is misinterpreted as epiglottic entrapment by the aryepiglottic folds
  • May be associated with epiglottic abscess or chondritis

CBC/Biochemistry/Urinalysis!!navigator!!

N/A

Other Laboratory Tests!!navigator!!

N/A

Imaging!!navigator!!

Imaging is not usually performed.

Other Diagnostic Procedures!!navigator!!

  • During endoscopy, the epiglottis may appear swollen and discolored (reddish-purplish), primarily along the lateral margins and ventral (lingual) mucosal surfaces. Epiglottis may appear more rounded and bulbous. The ventral mucosal surfaces often are ulcerated, and in more chronic cases granulation tissue surrounded by fibrous connective tissue is seen
  • If ulceration is seen at the rostral tip or dorsal surface of the epiglottic cartilage one should suspect associated epiglottic chondritis and abscessation
  • Horses with epiglottiditis often intermittently or persistently displace the soft palate dorsally
  • The caudal free margin of the soft palate may have a variable amount of inflammation, ulceration, or thickening

Treatment ⬆ ⬇

TREATMENT

  • •Outpatient (stall-side) basis
  • •Discontinue exercise for a minimum of 7–21 days, depending on the extent of the problem
  • •If swallowing is difficult or stimulates coughing, hay may need to be eliminated completely or partially from the diet

Medications ⬆ ⬇

Outline

MEDICATIONS

Drug(s) of Choice!!navigator!!

  • Horses are initially treated with phenylbutazone (4.4 mg/kg IV) or flunixin meglumine (1.1 mg/kg IV) and dexamethasone (0.044 mg/kg IV). Spray 20 mL of a pharyngeal spray (140 mL of DMSO, 140 mL of glycerin, 266 mL of distilled water, and 14 mL of dexamethasone 4 mg/mL and often an antibiotic such as nitrofurazone) into the pharynx twice daily for 7–14 days through a 10 F catheter introduced via the nasal passages
  • Antimicrobial therapy may be indicated if infection is suspected—procaine penicillin G (IM), trimethoprim–sulfamethoxazole (PO), ceftiofur (IM, IV) at usual recommended dosages for 5–7 days

Contraindications/Possible Interactions!!navigator!!

No contraindications.

Follow-up ⬆ ⬇

Outline

FOLLOW-UP

Patient Monitoring!!navigator!!

Substantial improvement of the epiglottis and adjacent tissue and in pharyngeal function usually is seen at follow-up endoscopy after about 1 week of therapy. Continue rest and therapy until healing is judged complete (repeated endoscopy performed at 1 week intervals).

Prevention/Avoidance!!navigator!!

Horses with more chronic-appearing inflammation or with associated epiglottic abscess and/or chondritis may require more protracted therapy (2–4 weeks), and complete resolution of thickening and cartilage deformity may not occur. Occasionally, epiglottic entrapment may develop.

Possible Complications!!navigator!!

Healing may result in fibrosis or cicatrix on the lingual epiglottic surface sufficient to interfere with normal soft palate function. Endoscopy may reveal intermittent or persistent dorsal displacement of the soft palate, which may need surgical treatment.

Expected Course and Prognosis!!navigator!!

Epiglottiditis is a serious, potentially career-limiting or -ending problem in racehorses. Prognosis depends primarily on severity of the condition during the initial examination and the degree of involvement and resulting deformity of the epiglottic cartilage. Resolution of acute inflammation results in complete return to normal exercise tolerance.

Miscellaneous ⬆ ⬇

Outline

MISCELLANEOUS

Abbreviations!!navigator!!

DMSO = dimethylsulfoxide

Suggested Reading ⬆ ⬇

Hawkins JF, Tulleners EP. Epiglottitis in horses: 20 cases (1988–1993). J Am Vet Med Assoc 1994;205:1577–1580.

Infernuso T, Watts AE, Ducharme NG. Septic epiglottic chondritis with abscessation in 2 young thoroughbred racehorses. Can Vet J 2006;47:1007–1010.

Ortved KF, Cheetham J, Mitchell LM, Ducharme NG. Successful treatment of persistent dorsal displacement of the soft palate and evaluation of laryngohyoid position in 15 racehorses. Equine Vet J 2010;42:23–29.

Author(s) ⬆

Author: Norm G. Ducharme

Consulting Editors: Daniel Jean and Mathilde Leclère