SYPHILIS. — An eruption resembling psoriasis sometimes occurs in this dis ease, but the successive crops and the coalescence of lesions in psoriasis serve to distinguish it. (Cantrell.) Etiology.—Psoriasis occurs somewhat more frequently in males than in fe males, and at all ages, but it is most fre quently met with in subjects between 10 and 30 years of age, though it is by no means rare in infancy. It is essen tially a chronic disease. Psoriasis is not a local disorder, but depends upon a general condition, which repeatedly pro duces the eruption.
Psoriasis is dependent upon a blood state closely allied to that belonging to gout and rheumatism: the uric-acid diathesis. Free indulgence in meat tends greatly to aggravate the eruption, whereas its restriction, especially the avoidance of beef and mutton, including meat-extracts and strong soups, materi ally aids in its removal. (L. Duncan liulkley.) Psoriasis of the palm is occasionally met with in cases of acquired syphilis, but usually this is observed, according to Hutchinson, in individuals whose hands are more or less irritated by friction.
Tendency to psoriasis is frequently inherited, and often the disease may be observed in two or more generations.
Seasons seem to have some influence upon the disease, since in spring and autumn the disease often takes on an in creased vigor. Influences tending to lower the vitality seem also to play a part. Pregnancy and lactation are fre quent causes of its extension; it quently follows scarlet fever. If psori asis already exists the latter disease may cause extension of the eruption.
The pathological lesion consists in an hypertrophy of the upper cutaneous layers, characterized by keratosis. The
examination of 1500 sections taken from six untreated cases have led Munro (An nales de Dermat. et de Syph., No. 11, '98) to conclude that the disease is not due, as hitherto supposed, to some vice of formation of the corneous epidermis, the abnormal keratinization being an essentially secondary lesion. The primi tive lesions of psoriasis are miliary scesses of the epidermis, situated almost upon the surface of the corneous layer, and around these miliary abscesses the epidermic reaction produces an atosis. No specific micro-organism was found. The disease is not contagious.
In spite of recent researches on the etiology of psoriasis. we do not know its true nature, but only a certain number of predisposing causes. Psoriasis is often hereditary. Patients frequently show signs of "arthritism." It is more common in the male sex, and is often seen in vigorous subjects. The disease affects chiefly the parts of the skin by contact with clothes, or by s me traumatism in the knees, elbows, shoulders, etc. It may occur after vac cination. Sometimes it follows excesses in eating or drinking. In women it may at the menstrual periods or at the menopause. In fact. all circumstances leading to temporary or permanent pression favor the eruption of psoriasis. .Balzer (Revue de Therap., May 15, 1902).
local treatment is of secondary importance, the disease being a manifestation of a general disorder.
If a gouty diathesis be traceable, propriate remedies are indicated (see