Impetigo%20-and-%20ecthyma Signs and Symptoms
Definition
Impetigo
- A very contagious, superficial, bacterial skin infection that easily spreads among people in close contact
- Most cases occur in children and resolve spontaneously without scarring in approximately 14 days
Ecthyma
- Deeply ulcerated form of impetigo that extends to the dermis
- “Punched-out” ulcers with yellow crust and elevated violaceous margins
Epidemiology
Nonbullous Impetigo
- Most common form of impetigo
- Also known as crusted impetigo or impetigo contagiosa
- Most common in children 2-5 years of age
- Complication: Risk of glomerulonephritis especially in children aged 2-6 years
Bullous Impetigo
- Newborns and younger children are commonly affected
Ecthyma
- Typically occurs in children 6 months-18 years, in the elderly, immunocompromised (eg neutropenia, human immunodeficiency virus [HIV]), or patients with diabetes mellitus (DM)
- May be a de novo infection or a superinfection
Etiology
Nonbullous Impetigo
- Staphylococcus aureus and group A beta-hemolytic streptococci (GABHS) (Streptococcus pyogenes)
Bullous Impetigo
- Always caused by coagulase-positive S aureus
- A localized form of staphylococcal scalded skin syndrome
Ecthyma
- GABHS (S pyogenes); S aureus is typically cultured from the lesions but is usually a secondary pathogen
Signs and Symptoms
Nonbullous Impetigo
- Initially presents with macules or papules that quickly become small vesicles
- Vesicles quickly pustulate and rupture leaving an erosion or clusters of erosion
- Purulent discharge dries and forms honey-colored crusts
- Usually asymptomatic though local adenopathy is common; pruritus or pain may occur occasionally
- Lesions are typically found on exposed areas of the skin on the face (especially around the nose and mouth) and extremities
- Carrier state: 4% of adults may be asymptomatic carrier
Bullous Impetigo
- Lesions (0.5-3 cm in diameter) typically develop on intact skin and begin as vesicles that turn into flaccid bullae that contain yellow serous fluid
- Bullae rupture easily and a moist red-surfaced erosion appears surrounded by a thin rim of scale, which then forms a thin varnish-like light brown crust
- Generally, there is no surrounding erythema but may have regional lymphadenopathy, pain, or systemic symptoms
- Lesions are often multiple, rapidly spread, and typically found on the face, buttocks, perineum and extremities, the trunk more frequently affected; in neonates, around the diaper area
Ecthyma
- Lesions initially appear as pustules and vesicles that become ulcerated
- Ulceration is frequently covered by adherent crusts
- Associated with pain and lymphadenopathy; heals with scarring
- Lesions are usually found on the buttocks, legs and feet
Risk Factors
Nonbullous Impetigo
- Poor hygiene; warm climate; crowding; preceding skin breaks in the affected area from insect bites, wounds, viral infections (chicken pox, herpes simplex), scabies or burns; prior skin disease (eg eczema, atopic dermatitis)
Ecthyma
- Insect bites, scabies, pediculosis, poor hygiene and malnutrition, heat and high humidity