Impetigo
Impetigo
Disease History, Characteristics, and Transmission
Introduction
Impetigo is a skin disorder characterized by crusting lesions and commonly occurs among children at an early school age. Infection is due to either Staphylococcus or Streptococcus bacteria and occurs at sites of skin trauma such as bites, scratches, or cuts.
Symptoms present as a tiny cluster of fluid-filled blisters that weep after bursting and form a crust. Fluids at these sites, as well as the nasal fluids of persons who harbor the causative agent in their nose, carry infection and allow for easy transmission between people. Washing sores with antibacterial soap and covering them can prevent transmission of the bacteria.
Treatment with antibiotics is usually very effective, and sores generally heal slowly without scarring. Prevention is achieved through good hygiene practices such as handwashing and treatment of other skin sores to prevent establishment of infection. Impetigo and its causative pathogens (disease-causing organisms) are found throughout the world.
Disease History, Characteristics, and Transmission
Impetigo is a skin disorder that results from bacterial infection, commonly by Staphylococcus aureus but also by Streptococcus bacteria. Infection usually occurs when the protective barrier of the skin is irritated or breached due to cuts, scratches, insect bites, or eczema.
The disease is one of the most common among children and is characterized by crusting skin lesions usually located around the nose, mouth, hands, and forearms. Symptoms begin as small pimplelike sores surrounded by reddened skin, which quickly develop into fluid-filled blisters. Once the blisters rupture, that patch of skin will continue to weep and a yellowish crust will develop over four to six days. The lesions may vary slightly depending on the causative agent, but generally symptoms have the same presentation and will appear around two to three days after infection.
Impetigo is extremely contagious and transmission occurs through contact with the infected site, nasal fluid, or fomites (items such as clothing and bedding that contain infected material on their surface). Scratching may also spread the lesions.
WORDS TO KNOW
COLONIZATION: Colonization is the process of occupation and increase in number of microorganisms at a specific site.
FOMITE: A fomite is an object or a surface to which an infectious microorganism such as bacteria or viruses can adhere and be transmitted. Transmission is often by touch.
PATHOGEN: A disease causing agent, such as a bacteria, virus, fungus, etc.
IN CONTEXT: REAL-WORLD RISKS
Impetigo refers to a very localized bacterial infection of the skin. It tends to afflict primarily children, but can occur in people of any age. Impetigo caused by the bacteria Staphylococcus aureus (or staph) affects children of all ages, while impetigo caused by the bacteria called group A streptococci (Streptoccus pyogenes or strep) are most common in children ages two to five years.
Scope and Distribution
Those most commonly affected by impetigo are toddlers and school children between the ages of two and six years old, with peak incidence usually occurring in the hot and humid weather of the summer months. The disease tends to occur in small outbreaks, although epidemics are rare.
Impetigo often follows a recent upper respiratory tract infection caused by streptococcus bacteria, and people who suffer from cold sores may also have a higher chance of developing the disease.
There is often no apparent source of infection for impetigo. This is due largely to the fact that Staphylococcus aureus is part of the human body's normal flora, which means that it is one of many bacteria that readily colonize areas of the human body without causing infection. Staphylococcus bacteria are commonly found on the skin's surface, nose, and mouth and cause infection when they enter open wounds at these sites.
Treatment and Prevention
The focus of treatment for impetigo is to cure the infection and to relieve symptoms. If the infection is limited to a small area, a topical antibiotic ointment will generally be sufficient. If this is not effective, oral antibiotics may be required. Healing will begin within a few days of treatment and sores generally clear within ten days without severe scarring.
Prevention of impetigo may be achieved by maintaining good hygiene practices such as regular handwashing, bathing, and tending to skin injuries such as cuts, scrapes, bites, and rashes. To prevent passing along infection, infected sites should be covered and items such as linen and cutlery should not be shared.
Impacts and Issues
Impetigo, although often widespread, generally poses little threat to communities and treatment is readily available in developed countries. The ease of transmission between people infected is heightened among groups of young children where limiting contact can prove difficult. In situations of outbreak among school groups, it is important that parents and teachers work together to ensure the infected children are appropriately and effectively treated while those not infected are successfully protected.
Evidence suggests that geography and climate will influence the primary infective organism causing impetigo. In developing nations and warmer climates, Streptococcus bacteria is the most common. In rare cases, impetigo caused by Streptococcus bacteria can progress deeper than the skin. One such complication arising from infection by Streptococcus may lead to damage of the kidneys, heart, or other organs. This makes early detection and treatment important in these developing regions.
IN CONTEXT: EFFECTIVE RULES AND REGULATIONS
The Centers for Disease Control and Prevention (CDC), Coordinating Center for Infectious Diseases, Division of Bacterial and Mycotic Diseases states that The spread of all types of GAS infection (Group A Streptococcal Disease (strep throat, necrotizing fasciitis, impetigo) can be reduced by good handwashing, especially after coughing and sneezing and before preparing foods or eating. Persons with sore throats should be seen by a doctor who can perform tests to find out whether the illness is strep throat. If the test result shows strep throat, the person should stay home from work, school, or day care until 24 hours after taking an antibiotic. All wounds should be kept clean and watched for possible signs of infection such as redness, swelling, drainage, and pain at the wound site. A person with signs of an infected wound, especially if fever occurs, should seek medical care. It is not necessary for all persons exposed to someone with an invasive group A strep infection (i.e. necrotizing fasciitis or strep toxic shock syndrome) to receive antibiotic therapy to prevent infection. However, in certain circumstances, antibiotic therapy may be appropriate. That decision should be made after consulting with your doctor.
SOURCE: Centers for Disease Control and Prevention (CDC), Coordinating Center for Infectious Diseases, Division of Bacterial and Mycotic Diseases
See AlsoBacterial Disease; Childhood Infectious Diseases, Immunization Impacts; Handwashing; Microorganisms; Staphylococcus aureus Infections; Strep Throat.
BIBLIOGRAPHY
Books
Mandell, G.L., J.E. Bennett, and R. Dolin. Principles and Practice of Infectious Diseases, vol. 2. Philadelphia, PA: Elsevier, 2005.
Mims, C., H. Dockrell, R. Goering, I. Roitt, D. Wakelin, and M. Zuckerman. Medical Microbiology. St. Louis, MO: Mosby, 2004.
Web Sites
Health Protection Agency. “Impetigo: Factsheet for Schools.” <http://www.hpa.org.uk/infections/topics_az/wfhfactsheets/WFHImpetigo.htm> (accessed March 6, 2007).
Medline Plus. “Impetigo.” Feb. 26, 2007 <http://www.nlm.nih.gov/medlineplus/ency/article/000860.htm> (accessed March 6, 2007).
Impetigo
Impetigo
Definition
Impetigo is a contagious bacterial infection of the skin. It primarily afflicts children and the elderly. Ecthyma is a more severe form of impetigo with sores affecting a deeper layer of the skin. It often leaves scarring and discoloration of the skin.
Description
The first sign of impetigo is a clear, fluid-filled bump, called a vesicle, which appears on the skin. The vesicle soon dries out and develops a scab-like, honey-colored crust, which breaks open and leaks fluid. These vesicles usually appear grouped closely together, and they may spread out and cover a large area of the skin. Impetigo often affects the area around the nose and mouth; however, it can spread to anywhere on the skin, but especially the arms and legs, as well as the diaper areas of infants. The condition called ecthyma is a form of impetigo in which the sores that develop are larger, filled with pus, and covered with brownish-black scabs that may lead to scarring. Impetigo infections most commonly occur during warmer weather.
Causes & symptoms
Impetigo is most frequently caused by the bacteria Staphylococcus aureus, also known as "staph," and less frequently, by group A beta-hemolytic streptococci, also known as "strep." These bacteria are highly contagious. Impetigo can quickly spread from one part of the body to another through scratching. It can also be spread to other people if they touch the infected sores or if they have contact with the soiled clothing, diapers, bed sheets, or toys of an infected person. Such factors as heat, humidity, crowded conditions, and poor hygiene increase the chance that impetigo will spread rapidly among large groups.
Impetigo tends to develop in areas of the skin that have already been damaged through some other means such as injury, insect bite, sunburn, diaper rash , chicken pox, or herpes, especially oral herpes. The sores tend to be very itchy, and scratching may lead to the spread of the disease. Keeping the hands washed with antibacterial soap and fingernails well trimmed are good precautions for limiting further infection.
Diagnosis
Observation of the appearance, location and pattern of sores is the usual method of diagnosis. Fluid from the vesicles can be cultured and examined to identify the causative bacteria.
Treatment
Echinacea tincture can be applied directly to the skin. The homeopathic remedy Antimonium tartaricum can be used when impetigo affects the face.
Bag Balm, an anti-bacterial salve, can be applied to sores to relieve pain and heal the skin.
A tincture of the pansy flower, Viola tricolor, can be taken internally twice daily for a week to speed healing.
Burdock root oil can be directly applied to the skin to help it heal.
Topical washes with goldenseal, grapefruit seed extract (which may sting), or tea tree oil are also recommended.
Allopathic treatment
Uncomplicated impetigo is usually treated with a topical antibiotic cream such as mupirocin (Bactroban). Oral antibiotics are also commonly prescribed. Patients are advised to wash the affected areas with an antibacterial soap and water several times per day, and to otherwise keep the skin dry. Scratching is discouraged, and the suggestion is that nails be cut or that mittens be worn—especiallly with young children. Ecthyma is treated in the same manner, but at times may require surgical debridement, or removal of the affected area.
Expected results
The vast majority of those with impetigo recover quickly, completely, and uneventfully. However, there is a chance of developing a serious disease, or sequela, especially if the infection is left untreated. Local spread of the infection can cause osteomyelitis, septic arthritis, cellulitis, or lymphangitis. If large quantities of the bacteria begin to circulate in the bloodstream, there is also a danger of developing a systemic infection such as glomerulonephritis or pneumonia .
Prevention
Prevention of impetigo involves good hygiene. In order to avoid spreading the infection from one person to another, those with impetigo should be isolated until all sores are healed, and their used linen, clothing, and toys should be kept out of contact with others.
Resources
BOOKS
Foley, Denise, et al. The Doctors Book of Home Remedies for Children: From Allergies and Animal Bites to Toothache and TV Addiction, Hundreds of Doctor-Proven Techniques and Tips to Care for Your Kid. Emmaus, PA: Rodale Press, 1999.
Shaw, Michael, ed., et al. Everything You Need to Know About Diseases. Springhouse, PA: Springhouse Corporation, 1996.
Weed, Susun. Healing Wise. New York: Ash Tree Publishing, 1989
OTHER
The Nemours Foundation. http://kidshealth.org/parent/general/infections/impetigo.html.
Patience Paradox
Impetigo
Impetigo
Definition
Impetigo refers to a very localized bacterial infection of the skin. There are two types, bullous and epidemic.
Description
Impetigo is a skin infection that tends primarily to afflict children. Impetigo caused by the bacterium Staphylococcus aureus (also known as staph) affects children of all ages. Impetigo caused by the bacteria called group A streptococci (also known as strep) are most common in children ages two to five.
The bacteria that cause impetigo are very contagious. They can be spread by a child from one part of his or her body to another by scratching or contact with a towel, clothing, or stuffed animal. These same methods can pass the bacteria on from one person to another.
Impetigo tends to develop in areas of the skin that have already been damaged through some other mechanism (a cut or scrape, burn, insect bite, or vesicle from chickenpox ).
Demographics
About 10 percent of all skin problems in children are ultimately diagnosed as impetigo.
Causes and symptoms
The first sign of bullous impetigo is a large bump on the skin with a clear, fluid-filled top (a vesicle). The bump develops a scab-like, honey-colored crust. There is usually no redness or pain , although the area may be quite itchy. Ultimately, the skin in this area will become dry and flake away. Bullous impetigo is usually caused by staph bacteria.
Epidemic impetigo can be caused by staph or strep bacteria and (as the name implies) is very easily passed among children. Certain factors, such as heat and humidity, crowded conditions, and poor hygiene increase the chance that this type of impetigo will spread rapidly among large groups of children. This type of impetigo involves the formation of a small vesicle surrounded by a circle of reddened skin. The vesicles appear first on the face and legs. When a child has several of these vesicles close together, they may spread to one another. The skin surface may become eaten away (ulcerated), leaving irritated pits. When there are many of these deep, pitting ulcers, with pus in the center and brownish-black scabs, the condition is called ecthyma. If left untreated, the type of bacteria causing this type of impetigo has the potential to cause a serious kidney disease (glomerulonephritis). Even when impetigo is initially caused by strep bacteria, the vesicles are frequently secondarily infected with staph bacteria.
Impetigo is usually an uncomplicated skin condition. Left untreated, however, it may develop into a serious disease, including osteomyelitis (bone infection), septic arthritis (joint infection), or pneumonia . If large quantities of bacteria are present and begin circulating in the bloodstream, the child is in danger of developing an overwhelming systemic infection known as sepsis.
Diagnosis
Characteristic appearance of the skin is the usual method of diagnosis, although fluid from the vesicles can be cultured and then examined in an attempt to identify the causative bacteria.
Treatment
Uncomplicated impetigo is usually treated with a topical antibiotic cream called mupirocin. In more serious, widespread cases of impetigo, or when the child has a fever or swollen glands, antibiotics may be given by mouth or even through a needle placed in a vein (intravenously).
Prognosis
Prognosis for a child with impetigo is excellent. The vast majority of children recover quickly, completely, and uneventfully.
Prevention
Prevention involves good hygiene. Hand washing; never sharing towels, clothing, or stuffed animals; and keeping fingernails well-trimmed are easy precautions to take to avoid spreading the infection from one person to another.
KEY TERMS
Systemic —Relating to an entire body system or the body in general.
Ulcer —A site of damage to the skin or mucous membrane that is characterized by the formation of pus, death of tissue, and is frequently accompanied by an inflammatory reaction.
Vesicle —A bump on the skin filled with fluid.
Resources
BOOKS
"Cutaneous Bacterial Infections." In Nelson Textbook of Pediatrics. Edited by Richard E. Behrman et al. Philadelphia: Saunders Company, 2004.
Darmstadt, Gary L. "Cellulitis and Superficial Skin Infections." In Principles and Practice of Pediatric Infectious Diseases, 2nd ed. Edited by Sarah S. Long et al. St. Louis, MO: Elsevier, 2003.
PERIODICALS
Sanfilippo, A. M. "Common bacterial skin infections." American Family Physician 66 (July 2002): 119–24.
Stulberg, D. L. "Common pediatric and adolescent skin conditions." American Family Physician 16 (October 2003): 269–83.
Wolfrey, J. "Pediatric exanthems." Clinical Family Practice 5 (September 2003): 55–7.
Rosalyn Carson-DeWitt, MD
Impetigo
Impetigo
Definition
Impetigo refers to a very localized bacterial infection of the skin. There are two types, bullous and epidemic.
Description
Impetigo is a skin infection that tends primarily to afflict children. Impetigo caused by the bacterium Staphylococcus aureus (also known as staph) affects children of all ages. Impetigo caused by the bacteria called group A streptococci (also know as strep) are most common in children ages two to five.
The bacteria that cause impetigo are very contagious. They can be spread by a child from one part of his or her body to another by scratching, or contact with a towel, clothing, or stuffed animal. These same methods can pass the bacteria on from one person to another.
Impetigo tends to develop in areas of the skin that have already been damaged through some other mechanism (a cut or scrape, burn, insect bite, or vesicle from chickenpox ).
Causes and symptoms
The first sign of bullous impetigo is a large bump on the skin with a clear, fluid-filled top (called a vesicle). The bump develops a scab-like, honey-colored crust. There is usually no redness or pain, although the area may be quite itchy. Ultimately, the skin in this area will become dry and flake away. Bullous impetigo is usually caused by staph bacteria.
Epidemic impetigo can be caused by staph or strep bacteria, and (as the name implies) is very easily passed among children. Certain factors, such as heat and humidity, crowded conditions, and poor hygiene increase the chance that this type of impetigo will spread rapidly among large groups of children. This type of impetigo involves the formation of a small vesicle surrounded by a circle of reddened skin. The vesicles appear first on the face and legs. When a child has several of these vesicles close together, they may spread to one another. The skin surface may become eaten away (ulcerated), leaving irritated pits. When there are many of these deep, pitting ulcers, with pus in the center and brownish-black scabs, the condition is called ecthyma. If left untreated, the type of bacteria causing this type of impetigo has the potential to cause a serious kidney disease called glomerulonephritis. Even when impetigo is initially caused by strep bacteria, the vesicles are frequently secondarily infected with staph bacteria.
Impetigo is usually an uncomplicated skin condition. Left untreated, however, it may develop into a serious disease, including osteomyelitis (bone infection), septic arthritis (joint infection), or pneumonia. If large quantities of bacteria are present and begin circulating in the bloodstream, the child is in danger of developing an overwhelming systemic infection known as sepsis.
Diagnosis
Characteristic appearance of the skin is the usual method of diagnosis, although fluid from the vesicles can be cultured and then examined in an attempt to identify the causative bacteria.
Treatment
Uncomplicated impetigo is usually treated with a topical antibiotic cream called mupirocin. In more serious, widespread cases of impetigo, or when the child has a fever or swollen glands, antibiotics may be given by mouth or even through a needle placed in a vein (intravenously).
Prognosis
Prognosis for a child with impetigo is excellent. The vast majority of children recover quickly, completely, and uneventfully.
Prevention
Prevention involves good hygiene. Handwashing; never sharing towels, clothing, or stuffed animals; and keeping fingernails well-trimmed are easy precautions to take to avoid spreading the infection from one person to another.
Resources
PERIODICALS
"Bullous Impetigo." Archives of Pediatrics and Adolescent Medicine 151, no. 11 (November 1997): 1168+.
KEY TERMS
Systemic— Involving the whole body; the opposite of localized.
Ulcer— An irritated pit in the surface of a tissue.
Vesicle— A bump on the skin filled with fluid.