skin disorders
Scabies Infestation
Symptoms of Scabies Infestation
The hallmark of scabies is intense itching, which is usually worse at night. The burrows of the mites are often visible as very thin lines up to a ½ inch (about 1 centimeter) long, sometimes with a tiny bump—the mite—at one end. Often, scratching of the itchy burrows results in a bacterial infection of the skin (so-called secondary infection). Sometimes, only tiny bumps are seen, many of which are scratched open because of the itching. The bumps can be anywhere on the body, including the breasts and penis. The bumps do not appear on the face in adults. The bumps first appear on the webs between the fingers, wrists, inner elbows, underarms, along the belt line, or buttocks. Over time, the burrows may become difficult to see because they are obscured by inflammation induced by scratching. People in warm climates develop small red bumps with few burrows. In people with dark skin, scabies can cause solid raised areas. In infants, the palms, soles, face, and scalp may be affected, especially behind the ears. In older adults, scabies can cause intense itching but very mild skin symptoms, which makes it a challenge for doctors to diagnose. This photo shows scabies bumps in the webbing between fingers. Image courtesy of the Public Health Image Library of the Centers for Disease Control and Prevention. The child in this photo has scratches and tiny reddish bumps clustered on the forearm and palm and in the creases of the wrist. These findings are typical of scabies. Burrows are ½-inch-long crusted bumps in the creases of the wrist and elsewhere. Photo courtesy of Karen McKoy, MD. This photo shows raised areas of scabies on the soles of an infant. © Springer Science+Business Media People who may develop a severe infestation (called crusted scabies or Norwegian scabies) include Those with a weakened immune system (caused by human immunodeficiency virus [HIV] infection, blood cancer, or chronic use of corticosteroids or other drugs that suppress the immune system) Those with severe physical disabilities or intellectual disability Aboriginal Australians Severe infestations cause large areas of thickened, crusted skin (particularly on the palms and soles in adults and on the scalp in children) that do not itch. Scabies incognito is a different form of scabies that develops in people who use topical corticosteroids for extended periods of time. It is sometimes hard to recognize because it looks different from the usual forms of scabies, and the mites may be very difficult to find. 