Impetigo and Staphylococcal Skin Infections in Children

Overview / Definition Impetigo is an acute, highly contagious skin infection that primarily affects children, characterized by the presence of vesicles, pustules, and honey-colored crusts. It is predominantly caused by Staphylococcus aureus and Streptococcus pyogenes. Staphylococcal skin infections encompass a range of conditions, including impetigo, folliculitis, and cellulitis, all of which can present similarly and require appropriate management. Epidemiology Impetigo is one of the most common bacterial skin infections in children, particularly between the ages of 2 and 5 years. The incidence peaks in late summer and early fall, often associated with warmer weather and increased outdoor activities. Prevalence rates are higher in crowded settings such as schools and daycare centers. Risk factors include poor hygiene, pre-existing skin conditions (e.g., eczema), and close contact with infected individuals. Pathophysiology / Mechanism Impetigo typically follows a breach in the skin barrier, which allows for bacterial colonization and subsequent infection. The mechanisms of infection involve: Adhesion: Bacteria adhere to the skin through fibrinogen and fibronectin. Toxin production: Staphylococcus aureus produces toxins that damage epithelial cells and disrupt local immune responses. Inflammatory response: The body’s immune response leads to the clinical manifestations of vesicles and crusting. Clinical Presentation Impetigo typically presents with: Lesions: Initially as vesicles or pustules that rapidly rupture, leading to oozing and crusting. Location: Commonly affects exposed areas, particularly the face, arms, and legs. Symptoms: Generally mild, though pruritus may be present. Staphylococcal skin infections can also present as: Folliculitis: Inflammation of hair follicles, presenting as pustules. Furunculosis: Deeper infection of hair follicles leading to painful nodules. Cellulitis: Diffuse inflammation of the skin and subcutaneous tissue, often presenting with