What is the treatment for a patient presenting with a strep rash indicative of scarlet fever?

Treatment of Strep Rash (Scarlet Fever)

Penicillin or amoxicillin is the first-line treatment for strep rash (scarlet fever) due to their proven efficacy, safety, narrow spectrum, and low cost. 1

Clinical Presentation of Scarlet Fever

Scarlet fever is characterized by:

• Distinctive macro-papular "sandpaper-like" rash 2, 3
• Typically occurs in children aged 5-15 years 1
• Associated with Group A Streptococcal (GAS) pharyngitis
• Common symptoms include:
  • Fever
  • Sore throat
  • Pain with swallowing
  • Headache
  • Nausea/vomiting
  • Abdominal pain
  • Tonsillar exudates
  • Palatal petechiae
  • Tender cervical lymphadenopathy 1

Antibiotic Treatment Options

First-line Treatment:

• Oral Penicillin V:

  • Children: 250 mg 2-3 times daily for 10 days
  • Adolescents/Adults: 250 mg 4 times daily OR 500 mg twice daily for 10 days 1

• Oral Amoxicillin (alternative first-line):

  • 50 mg/kg once daily (maximum 1000 mg) OR
  • 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1

For Penicillin-Allergic Patients:

• Clindamycin: 300-450 mg orally three times daily for 10 days
• Azithromycin: 12 mg/kg once daily (max 500 mg) for 5 days
• Clarithromycin: For patients with non-immediate penicillin allergy 1

Important Treatment Considerations

1. Full Course Completion: A complete 10-day course of antibiotics is essential for:

   • Complete eradication of the organism
   • Prevention of acute rheumatic fever
   • Reduction of symptoms 1

2. Early Treatment: Early initiation of antimicrobial therapy results in faster resolution of signs and symptoms 4

3. Treatment Window: Therapy can be safely initiated within 9 days of symptom onset and still prevent acute rheumatic fever 4

4. Medication Administration: The oral route should not be relied upon in patients with severe illness, nausea, vomiting, or intestinal hypermotility 5

Monitoring and Follow-up

• Patients should be monitored for improvement of symptoms within 24-48 hours of antibiotic initiation
• Follow-up throat cultures are not routinely recommended except for:
  • Patients with history of rheumatic fever
  • During outbreaks of acute rheumatic fever or post-streptococcal glomerulonephritis
  • During outbreaks in closed communities 4

Potential Complications if Untreated

Untreated scarlet fever can lead to:

• Suppurative complications (rare):

  • Peritonsillar abscess (quinsy)
  • Acute otitis media
  • Cervical lymphadenitis
  • Mastoiditis
  • Acute sinusitis 1

• Non-suppurative complications:

  • Acute rheumatic fever
  • Acute glomerulonephritis
  • Bacteremia
  • Pneumonia
  • Endocarditis
  • Meningitis 1, 3

Prevention and Control

• Maintain isolation precautions for minimum 24 hours after starting effective antibiotic therapy 1
• Encourage hand hygiene and avoiding close contact with infected individuals
• Advise against sharing utensils or drinks 1
• Maintain adequate hydration during recovery 1

Clinical Pearls

• Strep pharyngitis is usually self-limited; fever and constitutional symptoms typically disappear within 3-4 days even without treatment 4
• Clinical diagnosis of GAS pharyngitis cannot be made with certainty even by experienced physicians; bacteriologic confirmation is required 4
• In patients presenting with typical symptoms of scarlet fever, antibiotics should be prescribed immediately to reduce risk of complications and spread of infection 2