ITCH (AS. gycra, from giccan, 01-1G. jucelzan, Ger. jucken, to itch), also called SCABIES and PSORA. A parasitic disease of the skin, due to the presence of the lame or mature specimens of the Acorns (or Sarcoptcs) scabiei, which bur rows into the integument. The lesions are caused more by the scratching of the patient than by the presence of the insect. The resulting erup tion is multiform, papules, vesicles, and large enchymatous pustules occurring, besides crusts and scratch marks. In mild cases or early in an attack, the symptoms are' itching and a fee' papules or vesicles. The diagnosis is established by the discovery of the euniculus or burrow left by the female insect in the skin in the course of depositing her eggs. This appears as a minute, dotted. brownish-black line, curved or sinuous, from an eighth to a half inch long, rarely several inches long. These burrows may easily he seen by rubbing a little ink over the surface and then wiping the skin clean. The male insect remains on the surface. The female enters the skin at once, and may advance a twentieth of an inch a day. See ITCH-MITE.
Scabies is said by Bulkley to be uncommon in the United States, forming but 4.05 per cent. among 200,000 eases of skin disease collected by the American Dermatological Association. It is
common in Europe, especially among the poor and uncleanly, though found in all classes. Though other places may he first attacked. the earliest lesions are commonly found between the fingers and on the palmar surface of the wrist. The genital region, abdomen, thighs, anterior fold of the axilla, as well as all parts where there is warmth and pressure (as the waist and but tocks). are generally attacked, and in women the neighborhood of the nipples is early invaded by the eruption. The dermatitis resulting from the parasite and front the scratching caused by the itching is a simple inflammation of the skin, re sembling that caused by heat, cold. or mechanical irritants. The entrance of microiirganisms into the abraded surface may cause pustular lesions. The treatment for the condition is first directed to killing the insects and their eggs. This re sult is effected by the use of sulphur. Naphthol, ichthvol. oil of cade, and carbolic acid are also used, to allay the itching and reduce the inflam mation. Reinfection from the patient's own gloves, muffs, bedding, etc.. is possible—an acci dent which may be obviated by baking or boiling the articles. See ACARUS FOLLICULORUM.