URTICARIA (HIVES; NETTLE RASH).
Definition.—A symptomatic disorder of the skin characterized by the sudden appearance of pinkish, hard, puffy ings, or wheals, usually pinkish-white, but varying greatly in color and shape. Symptoms. — The wheals are invari ably accompanied by local heat, marked pruritus, and fornication, and disappear early. Its fugitive character is nomonic. The size and form of the wheals vary greatly. and successive crops may appear in various parts of the body.
They may vary from the size of a cent piece to that of a silver dollar. In typical cases they are round or oval or appear as streaks or irregular patches.
The intensity of the subjective symptoms does not always correspond to the de gree of eruption, and these may con tinue quite awhile after the disappear ance of the skin-lesion. Again, the symptoms may be irregular, the itching preponderating at times, the burning at others, etc. The rash may appear at one spot, disappear, then suddenly ap pear all over the body; again, it may de velop slowly. The mucous membrane of the mouth, pharynx, larynx, and vulva may be involved. In the larynx cedema may ensue and cause dangerous symptoms.
Case of pharyngeal urticaria seen in a young lady, in whom sudden severe dyspncea occurred while attempting to sing. In about ten minutes the erup tion or urticarial wheals were noticed on the skin. A spray of antipyrine and cocaine to the throat gave immediate re lief. J. M. Taylor (Phila. Med. Jour., Apr. 2, '98).
General malaise, pain in the legs, and fever have been observed in some cases.
The scratching and rubbing to which the patient resorts greatly aggravate the symptoms and cause fresh wheals to ap pear. The duration of urticaria varies from a few hours to a few days; periods of remission are usual. The eruption, as a rule, leaves no trace, though slight 'oedema may persist for a few hours.
Besides the ordinary form just de scribed, there are three varieties of urti caria: (a) acute febrile urticaria; (b) urticaria patulosa; (c) urticaria pigmen tosa. Acute febrile urticaria is rarely met with. It appears suddenly; the eruption is red and attended by much swelling. The trunk, face, and limbs are the areas of predilection. It often develops in the
mouth and throat and tends to cause dangerous laryngeal cedema. It greatly resembles scarlet fever. Urticaria pap ulosa is generally observed in children. It usually lasts a long time, even years, and is attended by remissions. The wheals are mixed with papules, and the itching and local irritation is exceedingly marked, especially at night. Urticaria pignmentosa differs from the other forms in being attended with a pigmentation of the skin, patches re sembling those observed in measles, or persistent tubercle-like prominences. Yellow patches persist after the active symptoms disappear. The itching, burn. ing, etc., are only marked after scratch ing. It is early observed.
Etiology.—Urticaria is due, in most instances, to the ingestion of shell-fish, especially lobster, crab, clams, mussels, oysters, etc., but it may also be caused by ordinary articles of food—fish, pork, various fruits, especially strawberries, raspberries, and peaches—which irritate the gastrointestinal tract and give rise to the rash through reflex action. In testinal parasites often give rise to urti caria in children from this. Another class of cases is ascribable to the stings and bites of venomous insects, fleas, mos quitoes, etc., or the irritating substances derived from jelly-fish, the Portuguese man-of-war so common in our Northern waters, caterpillars, and ants, and vari ous dyes. The sting of nettle-hairs may also be included in this category. Many drugs—especially copaiba, cubebs, tur pentine, quinine, and capsicum—may give rise to urticaria in persons that are unusually susceptible to their effects. It often attends other skin disorders, es pecially scabies, pityriasis, and eczema, mainly as a result of the scratching which intense pruritus renders practically un avoidable. Disorders of the genital tract, pregnancy, amenorrhcea, and constipa tion are frequent causes. Indeed, urti caria may occur as a symptom of almost any affection to which the human organ ism is liable. The rheumatic and gouty diathesis seem to predispose to it, or at least to be very closely associated with the appearance of urticarial wheals, or pomphi.