SKIN, DISEASES OF.—The skin being easily accessible to the eye as \yell as to the palpating finger, changes in its appearance are readily observed even by laymen. Many such changes are not due to skin-diseases proper, but are either temporary or long-lasting symptoms caused by internal affections (chlorosis ; cyanosis ; silver-poisoning ; etc.). See SKIN, CARE OF.
True skin-diseases may be caused by various harmful influences, such as by great heat or severe cold, by excessive dryness or moisture, by chemical substances (corrosive acids, blistering agents, etc.), by bacterial infection (smallpox, measles, scarlatina, syphilis), and, finally, by fungi and parasites. Since infectious and non-infections skin-diseases very often resemble each other very much, at times even being exactly alike in appearance, it is always advisable to call a physician as quickly as possible. Delay in obtain ing professional treatment is often the cause of a disproportionately long duration of the disease. " Critical eruptions " in the sense of the hydro therapists, as if the affection were driven from the interior of the body into the skin, do not exist. Eczema and itching herpes may arise in consequence
of (usually exaggerated) applications of water.
Eczema is an inflammatory, non-contagious affection of the skin, and is often caused by gastric or intestinal disturbances or by nervous disorders. It may be brought about also by great heat or cold, by the action of chemical agents (acids, etc.), and by parasites. Its course may be acute, but is more frequently chronic. The disease has been called also " running tetter," because it is usually attended with the secretion of a serous fluid. The eruption may occur in the form of vesicles, fissures, crusts, scales, pustules, or simple redness. Treatment consists in strict regulation of the diet, atten tion to the causative factor, and local applications (antiseptic powders, ointments, or washes).
For other affections of the skin, as well as for some of the more common diseases attended by skin eruptions, see the following articles : BIRTH