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DictionarySeescabiesNorwegian scabies
scabies [ska´bēz, ska´be-ēz] a contagious skin disease caused by the itch mite, Sarcoptes scabiei. Scabies, sometimes popularly called “seven-year itch,” is most likely to erupt in folds of the skin, such as in the groin, beneath the breasts, or between the toes or fingers. It is classified as a sexually transmitted disease.
The adult itch mite has a rounded body about one-fiftieth of an inch long. The skin lesions are caused by the female, which burrows beneath the skin and digs a short tunnel parallel to the surface, in which it lays its eggs. The eggs hatch in a few days, after which the baby mites find their way to the skin surface, where they mate and complete the life cycle.Symptoms. During the initial tunnel digging and egg laying, the human host may be oblivious to what is happening. There is little itching and there are few lesions. In about a month, the itching becomes intense because of hypersensitivity to the mite. The itch is often worse at night. The tunnels in the skin can now be discerned as slightly elevated grayish white lines. The mite itself can often be seen—with the aid of a magnifying glass—as a tiny black speck at the end of the tunnel. Blisters and pustules also may develop in the skin near the tunnel.Transmission. Scabies is usually transmitted from person to person by direct skin contact. Transmission via clothing and other inanimate objects is uncommon. Epidemics are fairly common in such places as camps, barracks, and institutions. It is unusual for one member of a family not to communicate it to the others. The Centers for Disease Control and Prevention recommend the wearing of gowns and gloves for close contact with an infested person. Masks are not necessary. All contacts that the patient has had should be treated at the same time.Treatment andPrevention. Scabies treatment consists of topical permethrin cream (Elimite), lindane, or crotamiton (Eurax), applied from the neck down and then washed off. For infants, 5 to 6 per cent precipitated sulfur in petrolatum, applied twice daily for a week, is usually adequate.Norwegian scabies a rare, severe form of scabies associated with a heavy infestation of Sarcoptes scabiei, seen especially in the senile and mentally retarded, in patients with poor sensation or severe systemic disease, and in immunocompromised patients; it apparently represents an abnormal host immune response to the etiologic agent. Characteristics include a marked crusting dermatitis of the hands and feet with subungual horny debris, erythematous scaling plaques on the neck, scalp, and trunk that may become generalized, and usually lymphadenopathy and eosinophilia.Nor·we·gian sca·biesa severe form of scabies with innumerable mites in thickened stratum corneum; has been linked with cellular immune deficiencies, including AIDS. Synonym(s): crusted scabies, Norway itchSevere scabies, seen in institutionalised persons—e.g., those with Down syndrome—or either debilitated or immunosuppressed patients, caused by Sarcoptes scabiei var hominis |