Feigned, or artificial, eruptions, occasionally met with in hysterical females and in others, are produced, for the purpose of exciting sympathy or of deception, by the action of friction, cantharides, acids or strong alkalies; the cutaneous disturbance may, therefore, be erythematous, vesicular, bullous, or gangrenous. It is usually limited in extent, and, as a rule, seen only on parts easily reached by the hands. [Illustration: Fig. 16. Dermatitis Factitia--note the unusually uniform and regular character and arrangement of the lesions.] #Dermatitis Gangraenosa.# #What do you understand by dermatitis gangraenosa?# Dermatitis gangraenosa (_erythema gangraenosum_, _Raynaud's disease_, _spontaneous gangrene_) is an exceedingly rare affection, characterized by the formation of gangrenous spots and patches. It may be idiopathic or symptomatic. Some of these cases, especially in hysterical subjects, belong under the "feigned eruptions," being self-produced. As an idiopathic disease, it begins as erythematous, dark-red spots--usually preceded and accompanied by mild or grave systemic disturbance--which gradually pass into gangrene and sloughing; the eventual termination may be fatal, or recovery may take place. As a symptomatic disease, it is occasionally met with in diabetes and in grave cerebral and spinal affections. In Raynaud's disease (symmetric gangrene) the parts affected are the extremities, such as fingers and toes, the ears and nose, only occasionally other parts. The first symptoms observed are coldness and paleness of the part; followed sooner or later by congestion of a dark red, livid, or bluish color, with sometimes swelling, and tenderness and shooting pains. The termination is usually in gangrene of a dry character, with, in some instances, vesicles and blebs along the edges; in other cases the parts become atrophied, withered, and indurated. Treatment is based upon general principles. #Erysipelas.# #What is erysipelas?# Erysipelas is an acute specific inflammation of the skin and subcutaneous tissue, commonly of the face, characterized by shining redness, swelling, [oe]dema, heat, and a tendency in some cases to vesicle- and bleb-formation, and accompanied by more or less febrile disturbance. #Describe the symptoms and course of erysipelas.#