Impetigo, bullous on the buttocks
Impetigo, bullous on the buttocks
Impetigo on a child's face
Impetigo on a child's face

Impetigo

Definition:
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.
Symptoms:
  • Skin lesion on the face/ lips, or on the arms or legs, spreading to other areas. Typically this lesion begins as a cluster of tiny blisters which burst, followed by oozing and the formation of a thick honey or brown colored crust that is firmly stuck to the skin.
  • Itching of the blister (vesicle):
    • Filled with yellow or honey-colored fluid
    • Oozing and crusting over
  • Rash (may begin as a single spot, but if child digs at it, it may spread to other areas).
  • In infants, a single or possibly multiple blisters filled with pus, easy to pop and when broken leave a reddish raw-looking base.
  • Lymphadenopathy -- local lymph nodes near the infection may be swollen.
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.

Review Date: 8/6/2001
Reviewed By: Michael Lehrer, M.D., Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2003 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.