Acute Hemi-glossitis.—An acute transitory swelling, confined to one half of the tongue, in the distribution of the lingual nerve, is occasionally met with. It is attended with great pain and high temperature, and is believed to be analogous to herpes zoster (Güterbock).
Mercurial Glossitis may accompany mercurial stomatitis ([p. 496]).
Chronic Superficial Glossitis.—Several forms of chronic superficial glossitis are met with. The most important, as it is frequently followed by the development of epithelioma, is that known as leucoplakia or leucokeratosis.
The tongue is studded over with white patches, which result from overgrowth and cornification of the surface epithelium, whereby it becomes thickened and raised above the surface, and at the same time there is small-celled infiltration of the submucous tissue. The patches are irregularly lozenge-shaped, and when crowded together they present the appearance of a mosaic ([Fig. 257]). Similar patches are often present on the mucous membrane lining the cheek.
Fig. 257.—Leucoplakia of the Tongue.
The disease is met with almost invariably in men between the ages of forty and fifty. Syphilis appears to be a predisposing factor, and any form of irritation—for example, the chewing or smoking of tobacco, the drinking of raw spirits, friction by a rough tooth or tooth-plate—plays an important part in inducing or in aggravating the condition.
The milder forms give rise to no discomfort, but when the condition is advanced the patient complains of dryness and hardness of the tongue, with impairment of the sense of taste and persistent thirst. When cracks, fissures, or warts develop, there is pain on chewing or speaking, or on taking hot or irritating food. The glands below the jaw may be enlarged.
The disease is most intractable and persistent, and even after disappearing for a time is liable to recur. After a variable number of years epithelioma is prone to develop, usually in one or other of the fissures which accompany the condition.