Scarlet fever is a contagious bacterial infection caused by group A Streptococcus (GAS) that produces an erythrogenic toxin. It primarily affects children and presents with a characteristic rash (Sandpaper), fever, and sore throat.

History and Examination

  • Children aged 1-10 years, recent exposure to someone with streptococcal infection
  • Risk factors: Crowded living conditions, school-aged children, winter or spring season

Symptoms

  • Sudden onset fever (moderate to high grade, continuous)
  • Sore throat
  • Headache
  • Abdominal pain
  • Nausea and vomiting

Signs

  • Rash (Sandpaper-like rash, starting on the chest and spreading to extremities; multiple tiny, pin head sized, erythe-matous papular lesions all over the trunk and extermeties)
  • Strawberry tongue
  • Pastia’s lines (accentuation of the rash in skin creases)
  • Facial flushing with circumoral pallor
  • Jugulodigastric lymphadenopathy

Differential Diagnosis (D/D) & Complications

D/D

  • Viral exanthems (measles, rubella, roseola)
  • Drug reactions (penicillin, sulfonamides)
  • Allergic rashes
  • Kawasaki disease (high fever, conjunctivitis, lymphadenopathy, erythema involving palm and soles, desquamation of tips of finger and toes)
  • Oral thrush

Complications

  • Acute rheumatic fever
  • Acute poststreptococcal glomerulonephritis
  • Streptococcal toxic shock syndrome
  • Suppurative complications (e.g., abscesses, cellulitis)
  • Streptococcal toxin (myocardits)
  • Bacterial invasion (septic arthritis, meningitis, osteomyelitis)

Investigation

  • Investigation of choice: Throat swab for rapid antigen detection test (RADT) and/or GAS culture
  • Complete blood count (leukocytosis)
  • C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR)
  • ASO titre (Raised)

Admission Criteria

  • Severe infection or complications
  • Poor oral intake, dehydration
  • Toxic appearance or altered mental status

Management

Medical

– Antibiotic therapy

– Analgesics and antipyretics for symptomatic relief

Rx:

  • Amoxicillin or Amoxyclav 60 mg/kg/day divided BID x 10 days (or)
  • Penicillin V 25-50 mg/kg/day divided QID x 10 days
  • (Flexon) Ibuprofen 10 mg/kg/dose TID or Paracetamol 10-15 mg/kg/dose TID for fever or pain relief
  • Syp Levocetrizine PO HS for 5 days
  • Calamine lotion LA TDS x 5 days

Advices

  • Encourage adequate hydration and rest
  • Isolate the affected child until at least 24 hours of antibiotic therapy has been completed
  • Educate the family on good hygiene practices to prevent transmission

Referral

  • If no improvement or worsening after 48 hours of antibiotic therapy
  • Presence of complications

Follow up

  • Schedule a follow-up visit within 7-10 days after treatment completion
  • Assess for clinical improvement, resolution of symptoms, and monitor for complications

Additional Points

  • Single episode of scarlet fever will confer permanent antitoxin immunity, the recurrences are not unusual.
  • Progression of disease:
    • Initially the tongue has heavy white coating and red swollen papillae appear 2-3 days later giving it a “white strawberry tongue” appearance. By 4-5th day, as the coating is shed, the tongue becomes smooth, bright red, has prominent papillae and appear as “red strawberry tongue” before reverting back to normal. By 2nd day a fine popular, punctate erythematous skin rash, that gives sand paper feel, begins in cephalo-caudal fashion. Accentuation of skin creases with transverse red streaks or Pastia’s lines are seen over axillary or antecubital folds.
    • The desquamation phase begins 7-10 days after resolution of the rash, with flakes peeling from the face. Peeling from the palms and around the fingers occurs about a week later and can last up to a month or longer.

References

1. Gerber MA, Baltimore RS, Eaton CB, Gewitz M, Rowley AH, Shulman ST, et al. Prevention of rheumatic fever and diagnosis and treatment of acute Streptococcal pharyngitis: a scientific statement from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee of the Council on Cardiovascular Disease in the Young, the Interdisciplinary Council on Functional Genomics and Translational Biology, and the Interdisciplinary Council on Quality of Care and Outcomes Research: endorsed by the American Academy of Pediatrics. Circulation. 2009;119(11):1541-1551.