AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Background

Scarlet fever is a syndrome characterized by exudative pharyngitis, fever, and scarlatiniform rash. It is caused by an infection with a pyogenic exotoxin-producing group A beta-hemolytic streptococci.

Pathophysiology

Streptococci are gram-positive cocci that grow in chains. They are classified by their ability to produce a zone of hemolysis on blood agar and by differences in carbohydrate cell wall components (A-H and K-T).

Streptococci may be alpha-hemolytic (partial hemolysis), beta-hemolytic (complete hemolysis), or gamma-hemolytic (no hemolysis). Most streptococci excrete hemolyzing enzymes and toxins. Erythrogenic toxins cause the rash of scarlet fever. The erythema-producing toxin was discovered by Dick and Dick in 1924.

Group A streptococci are normal inhabitants of the nasopharynx. Group A streptococci can cause pharyngitis, skin infections (including erysipelas pyoderma and cellulitis), pneumonia, bacteremia, and lymphadenitis. Scarlet fever is usually associated with pharyngitis; however, in rare cases, it follows streptococcal infections at other sites.

Infections occur year-round, but the incidence of pharyngeal disease is highest in school-aged children (5-15 y) during winter and spring and in a setting of crowding and close contact. Person-to-person spread by means of respiratory droplets is the most common mode of transmission. It can rarely be spread through contaminated food, as seen in a recent outbreak in China.¹

The incubation period for scarlet fever ranges from 12 hours to 7 days. Patients are contagious during the acute illness and during the subclinical phase.

Frequency

United States

Up to 10% of the population contracts group A streptococcal pharyngitis. Of this group, up to 10% then develop scarlet fever.

Mortality/Morbidity

In the preantibiotic era, infections due to group A beta-hemolytic streptococci were major causes of mortality and morbidity. Now with antibiotics, enhanced immune status of the population and improved socioeconomic conditions, the incidence and rate of complications of these infections has decreased.

Sex

No predilection is observed.

Age

Scarlet fever predominantly occurs in children aged 5-15 years.

CLINICAL

Section 3 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

History

• The prodrome is characterized by the following findings:
• • Sore throat
  • Headache
  • Vomiting
  • Abdominal pain
  • Fever
• The rash appears 1-2 days after onset of illness, first on the neck and then extending to the trunk and extremities.

Physical

• The patient usually appears moderately ill.
• Fever may be present.
• The patient may have tachycardia.
• Tonsils: Edematous, erythematous, and covered with a yellow, gray, or white exudate
• Petechiae on the soft palate
• Tender anterior cervical lymphadenopathy
• Flushed face with perioral pallor
• Scarlatiniform rash
• • Exanthem texture is usually of coarse sandpaper, and the erythema blanches with pressure.
  • The skin can be pruritic but usually is not painful.
  • A few days following generalization of the rash, it becomes more intense along skin folds and produces lines of confluent petechiae known as the Pastia sign. These lines are caused by increased capillary fragility.
  • The rash begins to fade 3-4 days after onset, and the desquamation phase begins. This phase begins 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.
• Appearance of the tongue
• • During the first 2 days of the disease, the tongue has a white coat through which the red and edematous papillae project. This is referred to as a white strawberry tongue.
  • After 2 days, the tongue also desquamates, resulting in a red tongue with prominent papillae called the red strawberry tongue.

Causes

Scarlet fever results from an erythrogenic toxin produced by group A streptococci.

DIFFERENTIALS

Section 4 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Other Problems to be Considered

Erythema toxicum
Enteroviral infection and nonspecific viral infection
Pediatric cellulitis
Severe sunburn
Arcanobacterium haemolyticum
Drug hypersensitivity
Viral exanthema
Plant allergic reactions

WORKUP

Section 5 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Lab Studies

• Throat culture or rapid streptococcal test
• Anti-deoxyribonuclease B and antistreptolysin-O titers (antibodies to streptococcal extracellular products)
• • This test can provide confirmatory evidence of recent infection but have no value in acute infection.
  • This test may be of value in patients with suspected acute renal failure or acute glomerulonephritis.

TREATMENT

Section 6 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Emergency Department Care

Treatment of streptococcal infections is primarily directed at preventing acute renal failure from poststreptococcal glomerulonephritis and suppurative sequelae (eg, adenitis, mastoiditis, ethmoiditis, abscesses, cellulitis).

Whether antibiotics prevent poststreptococcal glomerulonephritis is still debated in the literature.

Consultations

• Referral to an otolaryngologist for tonsillectomy may be recommended for patients with recurrent pharyngitis.

MEDICATION

Section 7 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Treat patients with a standard 10-day course of oral penicillin VK or erythromycin. Patients can also be treated with a single IM injection of penicillin G benzathine. These regimens may prevent acute renal failure if antibiotics are initiated within 1 week of the onset of acute pharyngitis.

Drug Category: Antibiotics

Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of the clinical setting.

Drug Name	Erythromycin (E.E.S.)
Description	Inhibits bacterial growth, possibly by blocking dissociation of peptidyl t-RNA from ribosomes, causing RNA-dependent protein synthesis to arrest. For treatment of staphylococcal and streptococcal infections. Appropriate therapy for patients allergic to penicillin.
Adult Dose	250 mg PO qid for 10 d
Pediatric Dose	30-50 mg/kg/d PO divided qid for 10 d
Contraindications	Documented hypersensitivity; hepatic impairment
Interactions	Coadministration may increase toxicity of theophylline, digoxin, carbamazepine, and cyclosporine; may potentiate anticoagulant effects of warfarin; coadministration with lovastatin and simvastatin, increases risk of rhabdomyolysis
Pregnancy	B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions	Caution in liver disease; estolate formulation may cause cholestatic jaundice; GI adverse effects are common (give doses pc); discontinue use if nausea, vomiting, malaise, abdominal colic, or fever occur

FOLLOW-UP

Section 8 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Deterrence/Prevention

• Children should not return to school or day care until they have completed 24 hours of antibiotic therapy.

Complications

• Suppurative complications
• • Cervical adenitis
  • Otitis media and/or mastoiditis
  • Ethmoiditis
  • Sinusitis
  • Peritonsillar abscess
  • Pneumonia
  • Septicemia, meningitis, osteomyelitis, and septic arthritis
• Rheumatic fever
• Acute renal failure from poststreptococcal glomerulonephritis

Prognosis

• The prognosis is excellent; most patients fully recover.
• Attacks may recur.

Patient Education

• Patients must complete the entire course of antibiotics, even if symptoms resolve.
• Warn patients that they will have generalized exfoliation over the next 2 weeks.
• Emphasize warning signs for complications of streptococcal infection such as persistent fever, increased throat or sinus pain, and generalized swelling.
• For excellent patient education resources, visit eMedicine's Children's Health Center and Ear, Nose, and Throat Center. Also, see eMedicine's patient education articles Strep Throat and Skin Rashes in Children.

MISCELLANEOUS

Section 9 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

Medical/Legal Pitfalls

• Missing or not recognizing the diagnosis entirely, diagnosing a viral etiology, and failing to initiate antibiotics are the most common pitfalls.
• Other pitfalls include failure to obtain a history of penicillin allergy and administration of long-acting penicillin given intramuscularly (IM).

ACKNOWLEDGMENTS

Section 10 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

The authors and editors of eMedicine gratefully acknowledge the contributions of previous author, Kelli N McCartan, MD, to the development and writing of this article.

REFERENCES

Section 11 of 11

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• References

1. Yang SG, Dong HJ, Li FR, Xie SY, Cao HC, Xia SC. Report and analysis of a scarlet fever outbreak among adults through food-borne transmission in China. J Infect. Nov 2007;55(5):419-24. [Medline].
2. Chiesa C, Pacifico L, Nanni F, Orefici G. Recurrent attacks of scarlet fever. Arch Pediatr Adolesc Med. Jun 1994;148(6):656-60. [Medline].
3. Davis H, Karasic R. Pediatric infectious disease. In: Atlas of Pediatric Physical Diagnosis. 3^rd ed. 1997:355-7.
4. Fisher RG, Boyce TG. Rash syndromes. In: Moffet's Pediatric Infectious Diseases: A Problem-Oriented Approach. Lippincott Williams & Wilkins; 2005:374-6.
5. Gerber MA. Diagnosis and treatment of pharyngitis in children. Pediatr Clin North Am. Jun 2005;52(3):729-47, vi. [Medline].
6. Gerber MA. Group A streptococcus. In: Nelson Textbook of Pediatrics. Philadelphia, Pa: WB Saunders Co; 2004:870-4.
7. Hamour A, Bonnington A, Wilkins EG. Severe community acquired pneumonia associated with a desquamating rash due to group A beta-haemolytic streptococcus. J Infect. Jul 1994;29(1):77-81. [Medline].
8. Kaplan EL, Gerber MA. Group A, group C and group G beta-hemolytic streptococcal infections. In: Textbook of Pediatric Infectious Diseases. Philadelphia: PA: Saunders; 2004:1142-56.
9. Kleiegman RM, Feigin RD. Streptococcal infections. In: Nelson Textbook of Pediatrics. 14^th ed. Philadelphia, Pa: WB Saunders Co; 1992:698-703.

Article Last Updated: Dec 19, 2007