Scabies - Coping up with the Disease
What is this Condition?
In scabies, the skin is infested by parasitic itch mites (also known as Sarcoptes scabiei var. hominis ). Scabies occurs worldwide but is most common in areas that are overcrowded or where hygiene is poor.
What Causes it?
Scabies develops when the microscopic itch mites enter a human host and provoke a sensitivity reaction. Mites can live their entire lives in human skin, causing chronic infection. The female mite burrows into the skin to lay her eggs, from which larvae emerge to copulate and then reburrow under the skin.
Scabies is transmitted through skin or sexual contact. The adult mite can survive without a human host for only 2 or 3 days.
What are its Symptoms?
Typically, scabies causes itching that intensifies at night. Sometimes the burrows of the scabies mite can be seen as tiny white lines in the skin, and red lumps may also appear in this area. Common sites of infestation include the hands, wrists, waistline, nipples in women, and genitalia in men. In infants, the burrows (lesions) may appear on the head and neck.
Intense scratching can lead to severe excoriation and secondary bacterial infection. Itching may become generalized secondary to sensitization .
How is it Diagnosed?
Your doctor may be able to detect the itch mite by closely examining the contents of the scabies burrow. If not, a drop of mineral oil placed over the burrow, followed by superficial scraping and examination of the scraped material under a microscope, may reveal mite eggs or feces.
If diagnostic tests offer no positive identification of the mite and if scabies is still suspected (for example, if family members and close contacts of the person also report itching), the person may be given a therapeutic trial of a pediculicide (a lice-killing drug). If his or her skin clears, the diagnosis is confirmed.
How is it Treated?
Generally, scabies is treated by applying a pediculicide - Nix or Kwell cream - in a thin layer over the entire skin surface and leaving it on for 8 to 12 hours. To make sure all areas have been treated, this application should be repeated in approximately 1 week. Another pediculicide, Eurax cream, may be applied on 4 consecutive nights.
Infants and pregnant women may receive an alternative therapy, which consists of a 6% to 10% solution of sulfur applied for 3 consecutive days. A person with widespread bacterial infections may require systemic antibiotics.
Persistent itching may develop from repeated use of pediculicides.
An antipruritic emollient or topical steroid can reduce itching; steroids injected into the lesions may resolve reddened nodules.