Impetigo

Overview of Impetigo

Impetigo is characterized by crusting sores, which may be itchy and are often located around the nose and mouth, but can occur anywhere on the body. There are two main forms:

• Non-bullous impetigo: The most common type, presenting as honey-colored crusts over erythematous skin.
• Bullous impetigo: Characterized by larger blisters filled with fluid, which can rupture and leave yellow crusts.

1. Treatment Guidelines for Impetigo

First-Line Treatment for Localised Impetigo:

Topical Antibiotics are generally recommended as the first-line treatment for localised impetigo (less than 10% of the body surface affected). The main topical treatments are:

• Mupirocin (Bactroban): A topical antibiotic that is effective against both Staphylococcus aureus and Streptococcus pyogenes, the most common causes of impetigo.
  • Application: Apply mupirocin ointment or cream to the affected area three times a day for 5 days.
  • Consideration: If the impetigo is widespread or unresponsive to topical treatment, systemic antibiotics may be needed.

Second-Line Treatment:

• Fusidic acid (Fucidin): An alternative topical antibiotic, also effective against Staphylococcus aureus.
  • Application: Apply fusidic acid cream to the affected area two to three times a day.
  • Note: Fusidic acid is not recommended for long-term use because of the risk of resistance.

Guidelines:

• Topical antibiotics are typically sufficient for most cases of localised impetigo.
• Systemic antibiotics (oral) should be considered if the infection is widespread or if the patient is immunocompromised or has signs of systemic infection (e.g., fever).

Sources:

• NICE – Impetigo Treatment Guidelines
• CKS – Impetigo Management

Systemic Antibiotics (Oral):

For more extensive cases of impetigo, or if the patient is systemically unwell, oral antibiotics may be required. These include:

• Flucloxacillin (500 mg four times a day for 7 days) for Staphylococcal impetigo, which is the most common causative organism.
• Clarithromycin or Erythromycin (for penicillin-allergic individuals) for Streptococcal or mixed infections.
  • Flucloxacillin is preferred in non-bullous impetigo unless there is a known allergy to penicillin.

Treatment duration: Usually 7 days, and the patient should continue the full course even if the symptoms resolve early.

Sources:

• BAD – Impetigo Treatment
• DermNet - Impetigo Treatment

2. Non-Pharmacological Measures

While antibiotics (topical or oral) are the primary treatment, there are also some non-pharmacological measures to help manage impetigo:

• Keep the affected area clean and dry: Gently wash the infected skin with water and soap. Avoid scrubbing, which could spread the infection.
• Avoid scratching: This prevents further irritation and potential spread of the infection.
• Hand hygiene: Frequent hand washing and use of disposable tissues should be encouraged to prevent transmission.
• Avoid close contact: Children with impetigo should stay away from school or daycare until they have been on antibiotics for at least 48 hours.
• Cover sores: If possible, cover impetigo sores with a clean, dry bandage to limit contact with others.

3. Management of Impetigo in Special Populations

• Children: Impetigo is most common in children, but treatment for children is largely the same as for adults. However, topical antibiotics like mupirocin are usually preferred for younger children due to fewer side effects.
• Pregnancy: Both mupirocin and fusidic acid are considered safe for use in pregnancy, but oral antibiotics should be used with caution, especially in the first trimester.
• Immunocompromised Patients: Individuals with weakened immune systems or those with chronic skin conditions (e.g., eczema) may require more aggressive treatment with oral antibiotics.

4. Treatment for Recurrent or Resistant Impetigo

If impetigo recurs or does not respond to initial treatment, consider:

• Reassessing the diagnosis (consider other conditions, such as eczema herpeticum, which can mimic impetigo).
• Checking for possible resistant organisms, especially methicillin-resistant Staphylococcus aureus (MRSA). In such cases, alternative antibiotics such as clindamycin or trimethoprim-sulfamethoxazole may be necessary.

5. Complications of Impetigo

• Post-streptococcal glomerulonephritis: This is a rare but serious complication, particularly associated with Streptococcus pyogenes infections, which can lead to kidney problems.
• Cellulitis or Abscesses: If untreated or if the infection spreads deeper, impetigo can lead to cellulitis, abscess formation, or more severe infections like sepsis.

6. Prevention

• Good hygiene: To prevent impetigo, individuals should wash their hands regularly and avoid sharing personal items (like towels or razors).
• Early treatment: Prompt treatment of impetigo will reduce transmission and speed recovery.
• Avoid scratching: This reduces the risk of spreading the infection to other parts of the body or to others.

Summary of Key Points:

• First-line treatment for localized impetigo: Topical mupirocin or fusidic acid.
• Oral antibiotics (flucloxacillin) are needed for widespread or severe cases.
• Children with impetigo should stay home from school until 48 hours after starting antibiotics.
• Non-pharmacological measures: Hand hygiene, covering sores, and keeping the skin clean are essential for limiting spread.
• If recurrent or resistant impetigo occurs, reassess for other conditions or resistant bacteria like MRSA.

Useful Links for Further Reading:

1. NICE Guidelines for Impetigo
2. CKS – Impetigo Management
3. BAD – Impetigo Treatment
4. DermNet – Impetigo Overview

Always consult with a healthcare provider for a tailored treatment plan, especially for severe, recurrent, or complicated cases of impetigo.