Etiology, Pathogenesis, and Clinical Presentation of Acute Rheumatic Fever in Children

Introduction

Acute Rheumatic Fever (ARF) is an autoimmune inflammatory disease triggered by a preceding Group A Streptococcus (GAS) infection. It primarily affects children and can lead to significant cardiac complications.

Etiology

ARF occurs due to an immune system response to a streptococcal throat infection. The body's antibodies mistakenly attack its own tissues, particularly the heart, joints, skin, and nervous system.

Pathogenesis: Immune Response and Molecular Mimicry

The pathogenesis of ARF revolves around molecular mimicry. Streptococcal M protein shares structural similarities with human tissue proteins, leading the immune system to mistakenly target self-antigens. This results in inflammatory damage.

Key Steps in Pathogenesis:

• Streptococcal infection triggers the immune system.
• Cross-reactive antibodies attack host tissues.
• Inflammatory cytokines are released, exacerbating tissue damage.
• Long-term cardiac complications such as rheumatic heart disease may develop.

Clinical Presentation

Children with ARF present with a range of symptoms affecting multiple systems:

Major Clinical Features:

• Carditis: Inflammation of the heart valves leading to murmurs and heart failure.
• Polyarthritis: Migratory joint inflammation, affecting large joints.
• Sydenham’s chorea: Neurological manifestations with involuntary movements.
• Erythema marginatum: Distinct rash with reddish ring patterns.
• Subcutaneous nodules: Small, firm nodules over joints and bony surfaces.

Diagnosis and Management

Diagnosis follows the Jones Criteria, integrating clinical, laboratory, and echocardiographic findings. Treatment includes antibiotics for streptococcal eradication, anti-inflammatory drugs, and long-term cardiac monitoring.

Conclusion

Early recognition and management of ARF are critical to preventing complications, particularly rheumatic heart disease. Public health interventions focusing on streptococcal infection prevention remain essential.