From the Guidelines
Scarlet fever presents with a characteristic sandpaper-like rash, sore throat, fever, and a strawberry tongue, and is caused by group A Streptococcus bacteria that produce an erythrogenic toxin. The illness typically begins with a sudden onset of fever (101°F or higher), sore throat, headache, and swollen lymph nodes in the neck. Within 1-2 days, a distinctive rash appears that feels rough like sandpaper. The rash usually starts on the neck and chest before spreading to the rest of the body, sparing the face, but causing flushed cheeks. The tongue initially has a white coating with red dots (white strawberry tongue) that later sheds to reveal a bright red surface (red strawberry tongue) 1. Other symptoms may include nausea, vomiting, abdominal pain, and malaise.
Key Features of Scarlet Fever
- Sudden onset of fever (101°F or higher)
- Sore throat
- Headache
- Swollen lymph nodes in the neck
- Sandpaper-like rash
- Strawberry tongue
- Nausea, vomiting, abdominal pain, and malaise
Diagnosis and Treatment
The diagnosis of scarlet fever is typically made based on clinical presentation and laboratory confirmation of group A Streptococcus infection 1. Treatment requires a full course of antibiotics, typically penicillin V (250-500mg orally four times daily for 10 days) or amoxicillin (50mg/kg/day divided twice daily for 10 days) 1. For penicillin-allergic patients, alternatives include clindamycin or macrolides. Prompt antibiotic treatment is essential to prevent complications such as rheumatic fever, glomerulonephritis, and other post-streptococcal sequelae 1.
Prevention of Complications
It is essential to complete the full course of antibiotic treatment to prevent complications and reduce the risk of transmission to others 1. Additionally, good hygiene practices, such as frequent handwashing and covering the mouth and nose when coughing or sneezing, can help prevent the spread of the infection.
Recent Guidelines
Recent guidelines from the Infectious Diseases Society of America recommend the use of penicillin or amoxicillin as the first-line treatment for scarlet fever, with alternative antibiotics used in cases of penicillin allergy 1. These guidelines also emphasize the importance of prompt treatment and completion of the full course of antibiotics to prevent complications and reduce the risk of transmission.
From the Research
Presentation of Scarlet Fever
The presentation of scarlet fever can vary, but it is typically characterized by:
- Exanthema (a skin rash)
- Tonsillopharyngitis (inflammation of the tonsils and pharynx) 2 The disease is caused by Streptococcus pyogenes and can affect people of any age group, although it is primarily a pediatric illness 2.
Atypical Presentation
Atypical presentations of scarlet fever can occur, including:
- Atypical rash distribution that may go unrecognized or be misdiagnosed 2
- Rash limited to specific areas, such as the dorsum of the hand and feet, only till the level of wrists and ankles joints 2 A high degree of suspicion is required to diagnose these rare presentations, and early treatment is essential to limit the spread of the disease 2.