Can impetigo cause heart complications?

Cardiac Complications of Impetigo

Impetigo does not typically cause heart complications, but in rare cases, post-streptococcal glomerulonephritis can occur as a complication when the infection is caused by certain strains of Streptococcus pyogenes.

Understanding Impetigo and Its Complications

Impetigo is the most common bacterial skin infection in children, particularly those aged 2-5 years. It presents in two main forms:

• Nonbullous impetigo (70% of cases): Characterized by honey-colored crusts, caused by either Staphylococcus aureus or Streptococcus pyogenes 1
• Bullous impetigo (30% of cases): Characterized by large, flaccid bullae, caused exclusively by S. aureus 1

Potential Complications

While impetigo itself is generally a self-limiting condition that resolves within 2-3 weeks without scarring, complications can occur:

1. Post-streptococcal glomerulonephritis: This is the most serious potential complication of impetigo caused by certain strains of S. pyogenes. However, the Clinical Infectious Diseases guidelines note that this complication is rare in developed countries (<1 case/1,000 population per year) 2

2. Cardiac complications: Unlike rheumatic fever (which can follow streptococcal pharyngitis), impetigo is not typically associated with cardiac complications such as endocarditis or rheumatic heart disease.

Distinguishing from Other Streptococcal Infections

It's important to understand the difference between impetigo and other streptococcal infections:

• Streptococcal pharyngitis (strep throat) can lead to rheumatic fever, which may cause cardiac complications including rheumatic heart disease 2
• Impetigo caused by S. pyogenes is associated with post-streptococcal glomerulonephritis but not typically with cardiac complications 2

Management Implications

Given the potential, albeit rare, risk of post-streptococcal glomerulonephritis:

• Appropriate antibiotic treatment is recommended for impetigo, not only to relieve symptoms and prevent spread but also to reduce the risk of complications 3
• Treatment options include:
  • Topical antibiotics (mupirocin, retapamulin, fusidic acid) for limited disease
  • Oral antibiotics for extensive disease or when topical therapy is impractical 1

Clinical Pearls

1. The risk of post-streptococcal glomerulonephritis following impetigo cannot be reliably prevented by antibiotic treatment, but treatment is still recommended to reduce transmission and symptoms 2

2. Unlike rheumatic fever following streptococcal pharyngitis, which can lead to valvular heart disease, impetigo is not associated with development of cardiac valve lesions or endocarditis 2

3. When evaluating a patient with a history of impetigo and suspected cardiac symptoms, consider other more likely etiologies for the cardiac issues rather than attributing them to the prior skin infection

In summary, while monitoring for renal complications may be warranted in cases of streptococcal impetigo, routine cardiac evaluation is not indicated based on current evidence, as impetigo does not typically lead to cardiac complications.