Impetigo is a common bacterial infection of the superficial layers of the skin. It is highly contagious and tends to affect children, though anyone can get it. The two main bacteria that cause impetigo are Staphylococcus aureus and Streptococcus pyogenes. The infection can present in different forms, usually as non-bullous or bullous, and in more severe cases might progress to ecthyma, a deeper, ulcerative form. Impetigo usually appears where the skin is damaged, such as from cuts, insect bites, or eczema, but it may sometimes affect intact skin.
How Does Impetigo Present Clinically?
The clinical presentation of impetigo depends on the type. In non-bullous impetigo, there are initially small red papules or pustules which quickly rupture. After rupture, these produce superficial erosions which become covered by characteristic honey-coloured crusts. The lesions may be itchy or mildly painful. Healing usually occurs without scarring. In bullous impetigo, fragile blisters form, often filled with clear or yellow fluid; these break within a few days, leaving erosions and a rim of scale around the periphery. The fluid in the bullae may become cloudy; crusting follows. Ecthyma involves deeper erosion into the dermis, more crusting, and potentially scarring. Lesions are often around the nose and mouth, or on the extremities, but may occur anywhere skin is exposed or has been disrupted.
Why is Impetigo Contagious and Who is at Risk?
Impetigo spreads easily because the organisms live on skin and in nasal passages, and transmission happens via direct contact with sores or with contaminated items such as towels, clothing, or bedding. The risk is higher when the skin barrier is compromised by trauma, insect bites, eczema, or scabies. Warm, humid climates favor its spread, and crowded living conditions increase risk. Young children, especially ages two to five, are the most commonly affected group. Immunocompromised persons or those with other underlying skin conditions are more vulnerable.
How is Impetigo Diagnosed?
Diagnosis of impetigo is usually clinical, based on observing the lesions—papules or pustules that rupture, forming honey-coloured crusts, and the pattern of spread. In most cases laboratory tests or cultures are not needed initially. However, when lesions are numerous, extensive, failing to respond to treatment, or in immunocompromised people, a swab of the lesion may be taken to identify the organism and test antibiotic sensitivity. It is also important to differentiate impetigo from other skin conditions that may look similar, such as eczema, herpes, or fungal infections.
IBOOLO handheld dermatoscopes are all equipped with magnification function, together with polarized light function, which can better observe Impetigo and thus help users to diagnose Impetigo. As the basic model, the DE-3100 can meet all the needs, with 10X magnification function and two polarized light functions, white polarized and amber polarized.
What Treatments are Available for Impetigo?
Treatment depends on extent, severity, and the patient's age and health. For localized, mild non-bullous impetigo, topical antibiotic creams or ointments are first-line therapy. Before applying medication, cleansing of crusts with mild soap and water or antiseptic wash helps. If there are many lesions, if the infection is bullous, or if the patient is immunocompromised, then oral antibiotics are used. The choice of antibiotics should cover both Staphylococcus aureus and Group A streptococcus. Hygiene measures such as keeping nails short, not sharing towels or clothing, and covering lesions also play a key role.
Does Impetigo Have Complications?
Many cases resolve without serious issues if treated, but complications may occur. These include spread of the infection into deeper skin layers leading to cellulitis, or formation of abscesses. In some cases, post-streptococcal glomerulonephritis, an inflammation of the kidneys, may follow infection with certain streptococcal strains. Ecthyma may lead to scarring due to deeper erosion. Systemic symptoms such as fever or malaise are uncommon except in extensive disease or in very young children.
How Can Impetigo Be Prevented?
Preventing impetigo involves maintaining skin health and avoiding spread. Promptly cleaning and caring for cuts, insect bites, or other skin trauma reduces risk. Maintaining good hygiene, including regular hand washing, keeping skin clean, and avoiding sharing items like towels or clothing, is effective. In settings like childcare centers, covering active lesions and keeping children home until they are no longer infectious, usually after 24 hours of antibiotic therapy, helps reduce spread. Treating underlying skin conditions that disrupt the skin barrier, such as eczema or scabies, is also important.
Is the Prognosis Good for Impetigo?
With appropriate treatment, impetigo usually resolves in a few days to two weeks. Non-bullous impetigo tends to clear without scarring. Bullous impetigo and ecthyma may require longer treatment and may leave scarring if the infection penetrates into deeper layers. Resistance to certain antibiotics is increasing, which may slow response in some cases or require alternative medications. Most patients recover fully with minimal long-term effects.