What is the management of scarlet fever?

Management of Scarlet Fever

Treat all patients with scarlet fever immediately with oral Penicillin V (phenoxymethylpenicillin) 250-500 mg every 6-8 hours for a full 10-day course, regardless of illness severity. 1

Diagnostic Confirmation Before Treatment

• Obtain throat culture or rapid antigen detection test (RADT) to confirm Group A Streptococcus (GAS) infection before initiating antibiotics 1
• Throat culture remains the reference standard—collect specimens from the posterior pharynx and tonsillar surfaces bilaterally 1
• While confirmation is ideal, do not delay antibiotic initiation if clinical presentation is classic (sandpaper rash, strawberry tongue, exudative pharyngitis) 2, 3

First-Line Antibiotic Therapy

Penicillin V is the treatment of choice:

• Dosing: 250-500 mg orally every 6-8 hours for 10 days (alternative: 500 mg twice daily or 250 mg three times daily) 1
• Critical timing: Antibiotics can be started up to 9 days after symptom onset and still prevent rheumatic fever 1
• Infectivity: Patient becomes non-contagious after 24 hours of antibiotic therapy 1

Alternative Antibiotics for Penicillin Allergy

For patients without immediate hypersensitivity to β-lactams:

• First-generation cephalosporins are recommended 1

For true penicillin allergy:

• Macrolides (e.g., azithromycin, clarithromycin) are recommended 1
• Caution: Some strains of S. pyogenes may be resistant to macrolides 1

Co-amoxiclav considerations:

• Only consider if documented treatment failure with penicillin (uncommon) 1
• Not first-line due to broader spectrum, higher gastrointestinal side effects (diarrhea in 1 of 10 patients), and increased antibiotic resistance risk 1
• If used: Children 40 mg/kg/day (amoxicillin component) in 2-3 divided doses; Adults 500 mg twice daily, both for 10 days 1

Critical Medications to Avoid

• Never use sulfonamide antibiotics—associated with increased disease severity and mortality in streptococcal infections 1
• Never use aspirin in children under 16 years due to Reye's syndrome risk 1

Symptomatic Management

• Antipyretics (acetaminophen or ibuprofen) may be used for fever relief but do not replace antibiotics 1
• Encourage adequate hydration and rest 4

Monitoring and Follow-Up

Expected clinical response:

• Monitor for clinical improvement within 48-72 hours of starting antibiotics 1
• If symptoms persist beyond 3-5 days of antibiotic therapy: Reassess diagnosis and consider alternative pathogens 1

Follow-up recommendations:

• Clinical follow-up to ensure symptom resolution 1
• Post-treatment throat cultures are NOT routinely recommended unless symptoms persist or recur 1

Management of Close Contacts

• Routine throat cultures or treatment for asymptomatic household contacts is NOT necessary 1
• In outbreak situations: Perform throat cultures for all patients and treat only those with positive cultures 1

Infection Control Measures

For hospitalized patients:

• Isolate for minimum of 24 hours of effective antibiotic therapy 1
• Healthcare workers must use disposable gloves and aprons during patient contact 1
• Strict hand hygiene with soap and water or alcohol hand rub before and after patient contact 1

Key Clinical Pitfalls to Avoid

Distinguishing from viral pharyngitis:

• Scarlet fever rarely presents with cough, hoarseness, or conjunctivitis (these suggest viral etiology) 2, 5
• Viral pharyngitis typically shows conjunctivitis, coryza, cough, and diarrhea 5

Distinguishing from Kawasaki disease:

• Unlike Kawasaki, scarlet fever has exudative pharyngitis and responds rapidly to antibiotics 2

Recognizing classic features:

• Sandpaper-like rash beginning on trunk, spreading to extremities with perineal accentuation 2
• Strawberry tongue (initially white-coated, then bright red with prominent papillae) 2
• Tonsillopharyngeal erythema with or without exudates 2
• Palatal petechiae 2

Importance of Early Treatment

Early antibiotic therapy is essential to prevent serious complications:

• Acute rheumatic fever 3, 6
• Glomerulonephritis 3, 6
• Bacteremia, pneumonia, endocarditis, and meningitis 3
• Early treatment reduces infectivity period and overall morbidity 1