Infantigo: Types, Causes, Symptoms, Treatment, Prognosis, Complications, Diagnosis

Infantigo is medically known as Impetigo. It is a type of skin infection commonly observed in children, which is caused by certain bacteria. It was described for the first time by William Tillbury Fox. Impetigo is derived from Latin word ‘Impetere’ which means ‘to attack’. Infantigo is also known by other medical terms as enfantago, infitigo, infinitigo, infatigo, infentigo, impetigo.

Infantigo is a skin infection caused by gram positive bacteria Staphylococcus aureus (S. aureus) and/or Streptococcus pyogenes (S. pyogenes). Infantigo 70% of the cases occur in pre-school children of ages 2 to 5 years. Hence, infantigo is also called as ‘school sores’. It occurs less frequently in adults. The infection affects the face, arms and legs. It has characteristic appearance of red sores followed by yellow crusts which are itchy. Infantigo infection is highly contagious. It rarely develops complications. It can be treated with specific antibiotics.

Depending on the type of blisters, infantigo is distinguished into three types as nonbullous, bullous and ecthyma. Both nonbullous and bullous are major types while ecthyma is a rare type of infantigo.

It is most common form of Infantigo. It is also known as impetigo contagiosa. Approximately, 70% of the cases are caused by S.aureus while 5 to 10% cases are caused by S. pyogenes. Nonbullous form rarely occurs in children below 2 years of age.

Nonbullous Infantigo is characterized as red blisters or sores of size 1 to 2 cm, which appear around the nose and mouth. The sores although not painful are itchy and cause discomfort. These sores break open to release pus or fluid and form yellow colored scabs. These are followed by red marks which heal without leaving a scar. On scratching, the sores spread the infection to other parts of the body. Nonbullous form lasts for two weeks and responds very well to the treatment.

It is the second most common form of infantigo. It is mainly observed in children less than 2 years of age. Bullous type of infantigo appears in the new-born’s diaper area or neck folds. In case of adults they appear on the arms, legs and trunk.

Bullous type of infantigo is characterized as painless large sized blisters (up to 2 cm) which contain clear fluid that slowly becomes dark and cloudy. On breaking, the blisters release fluid and get healed to become yellow scabs. It is accompanied by fever and swollen lymph nodes. As compared to the bullous type, it lasts for a long time (more than a month). This type of infantigo responds well to the treatment.

Ecthyma is a rare type of nonbullous infantigo. It is caused by either S. aureus or S. pyogenes or by both. It is characterized by painful sores that penetrate deep into the skin. In an infected person, the sores are observed on arms, legs and trunk region. These sores are large sized blisters of 3 cm filled with fluid or pus. The sores leak to release fluid and form hard and thick gray colored scabs. They heal slowly and leave scars behind which makes them cosmetically dangerous. The regional lymph nodes are also involved.

Infantigo appears as red spots/sores on skin especially near the nose and mouth. The sores grow quickly into blisters, burst rapidly to release fluid or pus present within them and later form yellow colored crust outside. The sores may expand to cover more areas of the skin. After the crust phase, they become reddish and fade without leaving scars in case of both nonbullous and bullous types of infantigo.

Infantigo is mainly caused by Staphylococcus aureus and rarely caused by Staphylococcus pyogenes. In colder regions, it is caused by S. aureus; while in warm regions, it is mainly caused by S. pyogenes.

S.aureus is present as a normal flora on the skin and does not cause any harm. However, in case of break in the skin due to cuts, bruise, it gets entry to the inner layers of the skin where it multiplies and causes this infection. In addition, certain risk factors increase the chance of getting this skin infection such as breaks in the skin due to insect bites, burns, cuts, eczema, scabies and herpes infection. Also, warm and moist crowded places, poor hygiene, day care or preschool, and contact during sports increase the risk of getting infantigo.

Infantigo occurs worldwide with nearly 162 million children being affected. It is more prevalent in countries with low income, warm climate and unhealthy living conditions. Highest incidence of impetigo has been reported in 14 countries of Oceania. It can occur at any age and can affect both genders. Adults are less prone to this infection as compared to the children. Adults living in congested, humid and unhealthy places often show signs and symptoms of infantigo.

Generally, infantigo resolves on its own (self-healing) and without treatment patient gets better within three weeks. While with antibiotic treatment, the patient gets well within a week’s time. Severe cases should not be left unattended as they may develop complications.

Infantigo is diagnosed in clinics based on history and appearance of symptoms. However, the physician may advise bacterial culture and sensitivity tests to be performed in case of the drug resistant strains where the visual signs are not very clear.

Differential diagnosis needs to be performed to distinguish infantigo from other conditions such as scabies, discoid lupus, herpes simplex virus infection, and contact dermatitis.

Treatment of infantigo depends on the severity of the infection. Both topical application and oral antibiotics are used for treating Infantigo.

In case of mild uncomplicated infection, the doctor would prescribe topical application of antimicrobial creams mupirocin, retapamulin and fusidic acid. S. aureus and S. pyogenes are known to develop drug resistance against mupirocin and fusidic acid. Hence, retapamulin (FDA approved) is used as a treatment of localized infantigo.

Before applying the cream, it is necessary to gently clean the sores with warm water to ensure good penetration to the application. While applying the cream, one should use good quality latex gloves and these should be discarded after the work is completed. Further, the person should also thoroughly wash his hands.

In case of severe infection or a patient not responding to the topical application, oral dosage of antibiotics is recommended. These work quickly as compared to the topical application. Oral antibiotics include penicillin, amoxicillin, cephalosporins and macrolides. Combination of amoxicillin and clavulanate potassium can also be used for treatment. In case of larger areas, cephalexin, an oral antibiotic is prescribed. When Infantigo is caused by Streptococci alone, penicillin antibiotic is used.

Treatment with antibiotics speeds up healing, it prevents complications and spread of the infection. The course of antibiotics is for 7 days. It is important to complete the entire course of treatment in order to prevent recurrence and development of drug resistance. A child can go back to school 24 to 48 hours after starting antibiotic treatment or when the sores are completely healed.

Natural or alternative remedies such as use of tree oil, olive oil and manuka nectar have been recommended.

Generally, infantigo gets self-healed within ten days. It gets treated faster with intake of antibiotics. Therefore, its complications are very rare and observed in less than 2% of the population infected with infantigo. The complications if they occur are observed to be scarlet fever, cellulitis, septicemia, guttate psoriasis and post-streptococcal glomerularnephritis.

Infantigo spreads easily through contact with infected people. Therefore, maintaining strict cleanliness is very important. Following precautions need to be taken to avoid being infected:

• The sores should be washed gently with mild soap and then under the flowing tap water. Antiseptic solution should be applied and then covered with dressing.
• The infected person’s clothes, bedding, towels should be washed separately. Patient’s clothes should be kept separately from other family members clothes. Sharing of clothes and linens should be discouraged.
• The patient should maintain hygiene. Hence, nails should be cut short to avoid scratching and prevent spread of infection to other parts of body.
• While applying antibiotic cream one should wear soft latex gloves. After application the gloves should be discarded and hands should be thoroughly washed.
• Toys, sports equipment, clothes and bedding should be disinfected regularly to prevent spread of infection.
• Since infantigo is highly contagious, the patient should be kept in isolation. It means that a child with infantigo should be kept at home till the patient gets completely treated.

Infantigo or Impetigo is a highly contagious bacterial infection which commonly affects the children. Although treatment with appropriate antibiotic heals this infection and prevents its spread, yet there is a need for vaccine against this infection. Thus, more attention needs to be given to Infantigo as a public health problem.