Impetigo contagiosa

Sophie Matzik is a freelance writer for the medical team.

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Impetigo contagiosa (ringworm) is a highly infectious bacterial skin disease. It occurs mainly in children, rarely also in adults. Classic symptoms are fluid- or pus-filled blisters that form mainly in the mouth and nose area and on the hands. Read everything you need to know about impetigo contagiosa here: symptoms, causes, treatment and prognosis.

ICD codes for this disease: ICD codes are internationally recognized codes for medical diagnoses. They can be found, for example, in doctor's letters or on certificates of incapacity for work. L01

Impetigo contagiosa: description

Impetigo contagiosa (also called bark lichen, pus lichen or drag) is a bacterial skin disease that mainly affects children and very rarely adults. The classic hallmark of the disease are small skin vesicles that are filled with fluid or pus. When these blisters burst, a yellowish scab forms on the skin.

Highly contagious!

Impetigo contagiosa is highly infectious. Infection occurs directly through contact with infected people or indirectly through the use of the same objects (smear infection) such as cutlery. The disease can spread quickly, especially in schools and kindergartens - children with impetigo contagiosa should therefore stay at home. Infected people can infect other people as long as the open and purulent areas of the skin have not yet completely healed.

Usually the pathogens penetrate into scratched or injured skin. Children with neurodermatitis, chickenpox, scabies or a weakened immune system are therefore particularly at risk of infection - the pathogen can penetrate their bodies more easily.

In many healthy people, the pathogens (staphylococci or streptococci) are in the mouth and throat area without symptoms of impetigo contagiosa occurring.

Impetigo contagiosa: symptoms

The time between infection with impetigo contagiosa and the appearance of the first symptoms (incubation period) is two to ten days. Classic symptoms are blistered expectorations of the skin. Doctors differentiate between small-bubble ringworm (caused by streptococci) and large-bubble ringworm (caused by staphylococci). Impetigo contagiosa with small bubbles mainly affects the mouth and nose region and the hands, while large-bubble impetigo mainly affects the abdomen. Both forms are highly contagious.

Impetigo contagiosa usually begins with a local, itchy reddening of the skin (erythema) in the mouth and nose area. Small blisters and pustules then form on the skin. These are filled with fluid or pus and easily burst. As a result, the typical honey-yellow scab forms on the skin (pus lichen). It typically occurs in the form of asymmetrical, sharply demarcated and red-lined crusts. In the further course, these flake off and finally fall off on their own.

The contents of the vesicles as well as the scab are infectious. Impetigo contagiosa can easily be passed on to healthy people through them.

Large-bladder impetigo contagiosa can also have general symptoms such as fever and lymph node swelling in the affected area. The large-bubble shape is less common than the small-bubble shape.

In newborns and infants, the large-bladder form of impetigo contagiosa can be life-threatening because the skin's barrier function is still inadequate and the immune defense is still incomplete.

Special form: non-bullous impetigo contagiosa

Like the other two forms, non-bullous impetigo contagiosa begins with blistering on the skin, but this quickly disappears. Often the ringworm can only be recognized by the reddened skin and the formation of the yellowish scab that appears around the nose. Non-bullous impetigo contagiosa can affect any part of the body and requires long treatment.

Impetigo contagiosa: causes and risk factors

Impetigo contagiosa is caused by bacteria of the staphylococcal or streptococcal type. According to this, there used to be a distinction between two groups of the disease, depending on the trigger: One was that caused by staphylococci (Staphylococcus aureus) triggered large-bubble impetigo contagiosa. The second group included small-bubble impetigo contagiosa caused by streptococci and non-bullous impetigo contagiosa caused by beta-hemolytic streptococci. Since this pathogen-specific classification is not clinically justifiable, it is no longer used today.

The bacteria are transmitted through direct contact, especially through contaminated hands. But they also stay on dirty towels, dishes or other everyday objects for a long time. If such objects are used jointly by infected and healthy people, the infection can also be transmitted (smear infection).

Impetigo contagiosa: examinations and diagnosis

As a rule, the doctor makes the diagnosis of impetigo contagiosa on the basis of the clinical picture, i.e. the symptoms that occur. In unclear cases, a smear is taken from the skin or from the mouth and throat area. The pathogens can be detected in such a smear in the laboratory.

If the pathogen has been in the person's body for a long time, specific antibodies against the pathogen can be detected in the blood and urine.

Impetigo contagiosa: treatment

As with other diseases, the same applies to impetigo contagiosa: the earlier the disease is discovered and treated, the better the therapy and prognosis.

The following options can be considered for the treatment of impetigo contagiosa:

• In mild cases, a topical antiseptic can kill the bacteria and ensure quick healing.
• In severe cases, topical antiseptic treatment is not enough. Instead, an antibiotic (usually amoxicillin) that is taken orally is prescribed.
• Oral antihistamines can be given if the itching is severe.

In addition, moist compresses (against possible fever) and disinfecting ointments can support the therapy.

Hygiene prevents spread

In order to avoid the infection of other people during the therapy, it is very important to have good hygiene:

• After every contact with the sick, you should wash your hands thoroughly with soap to kill any bacteria that have been transmitted.
• Patients should have clean fingernails that are trimmed short. This prevents skin injuries and the rubbing in of germs.
• Patients should not touch or scratch sores or scabs to prevent the bacteria from spreading.
• Wash towels, bed linen and other textiles that have come into contact with the person concerned at 60 degrees in the washing machine. That kills the bacteria.

Children with lichen must also be released from attending kindergarten or school.

Impetigo contagiosa: disease course and prognosis

As a rule, the prognosis for impetigo contagiosa is good. If the therapy is carried out consistently, the disease heals without scars or other permanent damage.

Complications

In rare cases, complications such as:

• Inflammation of the deeper layers of the skin or soft tissues to which the pathogen has spread
• Localized swelling of the lymphatic pathways and lymph nodes (regional lymphangitis and lymphadenitis)
• Blood poisoning (sepsis)
• purulent conjunctivitis (conjunctivitis)
• Otitis media

A rare but serious complication of impetigo contagiosa caused by streptococci is inflammation of the kidneys. For this reason, a urine test (urine status) is usually carried out at the start of therapy and six weeks after the end of therapy. In most cases, the kidney inflammation only occurs after the symptoms of impetigo contagiosa have subsided.

In order to treat complications early, you should definitely see your doctor again if you have any of the following symptoms:

• as the scab spreads, it continues to redden and become inflamed
• if the scab does not heal after three days of treatment
• if a fever occurs
• if you feel unwell, breathlessness, rash, swelling, itching or stomach pain after taking the medication

If complications are recognized early and treated in good time, those affected continue to have a good prognosis. Impetigo contagiosa then usually heals completely, including complications.

Tags:  Diseases skin first aid