Allergic
Conditions of Pharynx
Manifestations of an allergic background may
present themselves in the pharynx as independent disorders or may occur in
association with allergic symptoms in the skin and elsewhere.
Angioedema is classified as acquired and hereditary.
It is a rapid development of edema in the subcutaneous tissue due to
extravasation of fluid into the interstitial tissue from a disruption in the
vascular integrity. It may occur as a sole presentation, in conjunction with
the development of urticarial lesions, or as a medical emergency as an
anaphylactic reaction. The pathogenesis of the edema results from inflammatory
mediators exerting influence on the capillaries and venules, which causes
dilation and increased permeability of the vasculature permitting leakage of
fluid into the surrounding tissues. An acute presentation is most often
triggered by an allergic reaction to food, drugs, latex, or insect bites. The
allergic edema involves not only the exposed mucous membranes but the deeper
connective tissues. The involved surfaces are suddenly distended by an
edematous fluid of a purely serous variety without an inflammatory reaction.
Such swellings can occur in the palate, uvula, or aryepiglottic folds and in
the arytenoids. The edema is characteristically in the supraglottis, but
isolated involvement of the epiglottis, aryepiglottic folds, and larynx may
also produce sudden threatening symptoms of asphyxia. The patient usually
complains of an abrupt difficulty in deglutition or respiration associated with
a sensation of a swelling or lump in the throat.
In uvular angioedema, or
Quincke disease, the uvula, soft palate, and tonsillar pillars become
distended with a pale edema, which protrudes into the pharynx and touches the tongue.
Swallowing is impaired, and air hunger may supervene. If the supraglottic
structures are involved, a sense of suffocation may be so oppressive that the
patient has the feeling of impending death. Epinephrine can be lifesaving when
the angioedema may progress to airway obstruction and impending suf- focation.
The general treatment is similar to that of other allergic conditions, namely,
avoidance of the pre- cipitating agent if possible and specific
hyposensitization. Antihistamines and corticosteroids are typically effective
in relieving the edema. In severe and urgent cases, an emergency tracheotomy
may be a lifesaving procedure. Peripheral eosinophilia is an inconsistent
finding in the evaluation of atopic disease.
Allergic pharyngitis may be a result of therapy with
antibiotics and throat lozenges. Isolated superficial ulcerations, varying by a
few millimeters in diameter and surrounded by a small area of erythema, can be
seen distributed throughout the soft palate, tonsillar pillars, buccal mucosa,
undersurface of the tongue, and lips. These, as a rule, have a whitish
membranous covering.
They may result from an
antigen present in the lozenge, such as an antibiotic or menthol, which is a
common ingredient in lozenges. More often, the ulcerations result from taking
broad-spectrum antibiotics; lesions may be produced by an allergy to an
antibiotic or by an opportunistic fungal infection incident to the effect of
the antibiotic on the normal oral flora. The use of antihistamines and steroids
will usually give prompt relief, and avoidance of the offending agent will
prevent recurrence.