Impetigo is a skin disorder caused by bacterial infection and characterized by crusting skin lesions .
Causes, incidence, and risk factors
Impetigo is a common skin infection. It is most common in children, particularly if they are exposed to poor hygienic conditions. In adults, it may follow other skin disorders. Impetigo may follow a recent upper respiratory infection such as a cold or other viral infection. It is similar to cellulitis , but more superficial, involving infection of the superficial skin (top layers) with streptococcus (strep), staphylococcus (staph), or both. The skin normally has many types of bacteria on it, but intact skin is an effective barrier that keeps bacteria from entering and growing within the body. When there is a break in the skin, bacteria can enter the body and grow there, causing inflammation and infection. Breaks in the skin may occur with insect bites , animal bites , or human bites ; or other injury or trauma to the skin. Impetigo may occur on skin where there is no visible break. Impetigo begins as an itchy , red sore that blisters , oozes and finally becomes covered with a tightly adherent crust. It tends to grow and spread. Impetigo is contagious. The infection is carried in the fluid that oozes from the blisters. Rarely, impetigo may form deeper skin ulcers .
Signs and tests
Diagnosis is based primarily on the appearance of the skin lesion . A culture of the skin or mucosal lesion usually grows streptococcus or staphylococcus.
Treatment
The goals of treatment are to cure the infection and relieve the symptoms. A mild infection is treated with topical (applied to a localized area of the skin) antibiotics prescribed by the health care provider. A typical topical agent would be a prescription antibacterial cream such as Bactroban. Oral antibiotics frequently are prescribed and result in rapid clearing of the lesions. Typical antibiotics include erythromycin or dicloxacillin. Wash the skin several times a day, preferably with an antibacterial soap, to remove crusts and drainage. Prevent the spread of infection. Use a clean washcloth and towel each time. Do not share towels, clothing, razors, and so on with other family members. Wash the hands thoroughly after touching the skin lesions .
Expectations (prognosis)
The sores of impetigo heal slowly and seldom scar. The cure rate is extremely high, but recurrences may be frequent in young children.
Complications
Spread of infection to other parts of the body. This is a common occurrence. Frequently a child is seen with multiple patches of impetigo. Systemic infection leading to kidney failure (post streptococcal glomerulonephritis ). This is a rare occurrence.
Permanent skin damage, scarring (also extremely rare).
Calling your health care provider
Call for an appointment with your health care provider if symptoms indicating impetigo are present.
Prevention
Good general health and hygiene help to prevent infection. Minor abrasions or areas of damaged skin should be thoroughly cleansed with soap and clean water. A mild antibacterial agent may be applied if desired. Impetigo is contagious, so avoid skin contact with drainage from impetigo lesions.