Antibiotics for Impetigo in Children

Introduction

Impetigo is a common skin infection which is particularly prevalent in young children but can affect anyone at any age. It is very contagious, commonly being spread by skin-to-skin contact. Treatment reduces the time during which impetigo is contagious and can avoid potential complications as a result of leaving the condition untreated.^1,2 

Overview of impetigo

Causes and risk factors

Impetigo is a bacterial infection of the skin, usually caused by Staphylococcus aureus or Streptococcus pyogenes. It is more likely to infect skin that is already damaged, e.g., either caused by a cut or graze, or through a pre-existing condition like eczema or psoriasis. You may also be more susceptible to impetigo if your immune system is working less well than it should, through having a condition like diabetes, or if you are currently having treatment with chemotherapy.^1,2      

Clinical presentation

There are two types of impetigo, non-bullous and bullous, which have slightly different symptoms associated with them.

Non-bullous impetigo

Non-bullous impetigo is the more common infection of the two and is usually found on skin exposed to the outside world, such as around the mouth and nose or on the limbs.  Non-bullous impetigo causes itchy red sores to develop on the skin, which burst and leave a characteristic golden-coloured crust as they dry and heal. This is sometimes described as looking like a cornflake stuck to the skin, and at this point, the sores are no longer contagious.  It is important not to scratch the itchy sores as this can pass the infection to other parts of the body. Sometimes you may also have a high temperature (fever), or swollen glands close to the sores, but this is not always the case.^1,2   

Bullous impetigo

Bullous impetigo is usually seen in children under the age of two years old. The main symptom of bullous impetigo is the presence of fluid-filled blisters called bullae. These are more likely to be found on the trunk (torso) of the body rather than on the face. Similarly to non-bullous impetigo, the blisters are contagious if scratched, and burst before healing with a golden-coloured crust. It is more common to experience swollen glands and a high temperature with bullous impetigo.^1,2    

Untreated impetigo

There are a number of complications that can result from leaving impetigo untreated, including:^1,2,3,4

• Ecthyma - this is a form of impetigo where the impetigo sores go deeper into the layers of the skin (also known as the dermis) creating painful, pus-filled ulcers
• Scarring - impetigo does not usually cause scarring, but this can be the case if not appropriately managed
• Spread of infection - bacterial infection can spread into deeper layers of the skin, causing cellulitis or in some cases septicaemia

Additionally, there are potential complications caused by the specific bacteria types related to impetigo:^1,2,3,4

• Scarlet fever - a bacterial infection common in young children, causing a widespread rash, fever, and sore throat 
• Staphylococcal scalded skin syndrome - a serious bacterial infection, causing peeling skin and requiring immediate medical treatment  
• Glomerulonephritis - inflammation of the internal structures of the kidneys, caused by streptococcal bacteria. This can be treated, but can also cause long-term issues with the kidneys

Antibiotics for impetigo

Topical antiseptics

Antibiotics are not always required to treat impetigo, and in some cases, non-bullous impetigo can be treated with 1% hydrogen peroxide cream if it covers a small area. Exceptions to this would include patients who are more at risk of complications of impetigo, or if the sores are near the eyes.^1,2,5

Topical antibiotics

Topical antibiotics are medications that are applied to the skin. These are suitable for small areas of non-bullous impetigo that would be unsuitable for hydrogen peroxide cream or for more widespread areas where the patient is otherwise well. The most commonly used topical antibiotics for impetigo are:^1,2,5

• Fusidic acid
• Mupirocin

In cases where non-bullous impetigo is widespread, the option to use either topical or oral antibiotics is possible and will depend on ease of use for the patient.  

Oral antibiotics

Oral antibiotics are used more commonly in impetigo for patients with non-bullous sores who are either showing other symptoms of infection (like a fever or swollen glands) or are at greater risk of having complications of impetigo. Additionally, all cases of bullous impetigo need to be treated with oral antibiotics. The oral antibiotic options available are:^1,2,5

• Flucloxacillin - if not allergic to penicillin 
• Clarithromycin or erythromycin for penicillin-allergic patients 

If impetigo does not improve with either hydrogen peroxide or topical antibiotics, the patient can progress onto either a topical antibiotic or oral antibiotic respectively. If oral antibiotics do not improve the condition, swab tests will be needed to ascertain what type of bacteria is causing the lesions and tailor the treatment to the specific bacteria. Your GP may take a swab from your skin or inside your nose.

Choosing the right antibiotic

The choice of antibiotic depends on the site and how widespread the impetigo is, as well as whether the patient is showing signs of a more serious infection or has a weakened immune system. 

Age-specific considerations

Children with bullous impetigo may need to be referred for specialist assessment, especially if they are under  one year old. Where the option of topical or oral antibiotics is presented, the choice may be narrowed down to how easy it would be to administer the medication, as both the topical and oral routes are equally effective - and this may depend on how widespread the impetigo is, as well as the age of the child.  

Administration and dosage

The British National Formulary for Children (BNFC) discusses the recommended dosage for all medications used in children. The healthcare professional treating your child will give exact instructions for how to administer the medication prescribed.

1% hydrogen peroxide cream 

Applied to the affected skin two to three times a day for 5-7 days. 

Topical antibiotic application guidelines

Fusidic acid

Fusidic acid is applied to the affected area three times a day for 5-7 days. Before applying the cream, gentle washing of the area with warm, soapy water is essential to remove any crusts that have developed. Washing your hands or wearing gloves to apply the cream will reduce the risk of spreading impetigo. Antibiotic resistance is a concern in any long-term antibiotic use, so fusidic acid will be used for no more than 10 days.

Mupirocin

As per fusidic acid, mupirocin is applied to the affected area three times a day for 5-7 days.  Mupirocin cream is not recommended in children under one year old, and so an alternative will be given.

Oral antibiotic dosage for children

Flucloxacillin

Flucloxacillin is given orally two to four times a day, for 5-7 days. The number of doses a day will depend on the age of the child with impetigo. Flucloxacillin is a member of the penicillin family of antibiotics, so it would not be given to children with a penicillin allergy.  

Clarithromycin or erythromycin 

Clarithromycin is given orally twice a day for 5-7 days. As with flucloxacillin, the dose used depends on the age of the child. Erythromycin is not given to children under eight years old; the dosage for children eight years and above is 250-500mg (milligrams) four times a day for 5-7 days.

Potential side effects

Topical treatments placed on the skin, do not have commonly associated side effects, but it is possible to have a skin reaction where the cream is placed.

Oral antibiotics 

There are a number of side effects common to all oral antibiotics used for impetigo such as:

• Diarrhoea and vomiting 
• Nausea 
• Skin reactions

Additionally, some side effects are specific to each antibiotic:

Flucloxacillin

• Thrombocytopenia - a reduced number of platelets are produced, resulting in bruising and slow healing of cuts and grazes

Clarithromycin and erythromycin

• Dizziness
• Reduced appetite
• Headache
• Hearing impairment 
• Insomnia - difficulty to fall and remain asleep 
• Paraesthesia (pins and needles) - numbness or tingling, usually felt in the hands and feet 
• Altered taste 

If you experience any of these symptoms, it is important to inform the healthcare professional who prescribed the antibiotics.

Allergic reactions to penicillin

It is important to monitor your child for symptoms of allergy to penicillin. This reaction will happen almost immediately after giving the antibiotics, and can include:

• Anaphylaxis  - a rapidly worsening allergic reaction that can cause widespread swelling of the mouth, eyes and extremities
• Urticaria (hives) - a rapidly appearing raised, itchy rash 

If your child has any of these symptoms, seek immediate medical assistance.

Compliance and follow-up

If prescribed topical or oral antibiotics, it is very important to complete the full course of treatment, even if the symptoms of impetigo have completely gone. This is to both avoid the impetigo infection returning and to prevent the bacteria from becoming resistant to being treated with this antibiotic again.^1,2

Impetigo often is treated successfully in a 7-10 day period, so it is important to see a doctor again if the symptoms have not completely resolved in this timespan. It may be the case that more investigations are required by a dermatologist to ensure the most effective treatment is being given.  

In cases where impetigo has been treated, but returns, you may have skin and nasal swabs to test whether you carry bacteria that makes you more likely to have a reinfection. If this is found to be the case, you may need antiseptic body wash and cream to stop further infections.

Prevention strategies

There are many ways to avoid an impetigo infection or prevent an infection from spreading to other family members:^1,2,5

• Practice good hand hygiene with soap and water or hand sanitiser
• Avoid touching or scratching impetigo sores 
• Don’t share towels and bedding, and make sure all are washed at a high temperature
• Keep sores loosely covered
• Keep cuts and scratches clean, and dress them to avoid infection 
• Avoid going to work or school until either the sores have broken and crusted over, or after 48 hours of treatment 
• Keep toys clean and sanitised 

Summary

Impetigo, a highly contagious skin infection, is common in children but can affect individuals of any age. It is caused by bacteria, primarily Staphylococcus aureus or Streptococcus pyogenes, and manifests in non-bullous and bullous forms. Treatment is crucial to reduce the spreading of the infection and to prevent further complications. Untreated impetigo can lead to complications such as ecthyma and scarring but can also potentially cause serious conditions like scarlet fever or staphylococcal scalded skin syndrome. Therefore, it is important to seek medical assistance if you believe your child has impetigo.

Treatments including topical antiseptics, topical antibiotics, and oral antibiotics, are commonly used. The choice depends on the severity of the patient’s impetigo, age, and risk factors such as a weakened immune system. Administration guidelines vary, and potential side effects, including allergic reactions, must be monitored and reported to a healthcare professional.

Compliance with the full antibiotic course is crucial to prevent recurrence and antibiotic resistance.  Referral to a dermatologist may be required if your impetigo infection keeps coming back or if your symptoms are worsening. 

Preventative measures include good hand hygiene, avoiding scratching or touching the sores, not sharing personal hygiene items, and keeping wounds clean. The combination of appropriate treatment and preventing the spread of impetigo makes for an effective management plan in children.