II. Pathophysiology
- Occurs in Group A beta-hemolytic streptococcal (GAS) infection (typically Streptococcal Pharyngitis)
- Some GAS strains produce streptococcal pyrogenic exotoxin
- Patients with Hypersensitivity to the toxin may develop a rash
III. Epidemiology
- May occur in up to 10% of Streptococcal Pharyngitis cases
- Age 3 to 10 years most commonly affected
IV. Symptoms
-
Fever
- Peaks on Day 2
- Returns to normal on Day 5-7
- Pharyngitis
- Headache
- Chills
- Vomiting
- Rash (see below)
V. Signs
- Forehead and cheeks appear flushed
- Circumoral pallor and sparing of rash
- Anterior Cervical Lymphadenopathy
- Pharyngitis
- Strawberry Tongue
- Sandpaper Rash (Scarlatiniform Rash)
- Onset with 12-72 hours after fever
- Coalescing, blanching erythematous Macules (may appear Sunburn-like)
- Fine papular or punctate lesions
- Texture of coarse sandpaper
- Rash distribution
- Starts on upper trunk
- Rash distribution generalizes within 24 hours
- Rash may affect flexor creases (Pastia lines) in the axillae, antecubital, groin and neck
- Pastia lines do not typically blanche
- Rash spares the palms and soles
- However, Desquamation of palms and soles may occur
-
Desquamation
- Follows rash fading after several weeks
- Desquamation of face, skin folds, hands and feet
- Desquamation may last up to 6 weeks
VI. Labs
- Streptococcal Rapid Antigen Test
-
Throat Culture
- Used to confirm a negative rapid Antigen test
- Antistreptolysin O titer (ASO Titer)
- Confirms diagnosis, but not typically helpful in acute disease
VII. Differential Diagnosis
- Staphylococcal Scalded Skin Syndrome
-
Kawasaki's Disease
- Also with Desquamation of palms and soles as well as strawberry Tongue
VIII. Management
- See Group A Streptococcal Pharyngitis for management
- Rash self-resolves in 4-5 days (often with Desquamation that may last weeks)