From the Guidelines
Scarlet fever is diagnosed through clinical examination and a throat swab test to confirm the presence of group A Streptococcus bacteria, and treatment primarily involves a 10-day course of antibiotics, with penicillin V being the first-line treatment, as recommended by the most recent guidelines 1. The diagnosis is based on characteristic symptoms including a red rash that feels like sandpaper, a strawberry-like tongue, sore throat, fever, and swollen lymph nodes.
- Clinical findings suggestive of GAS as the cause of an episode of acute pharyngitis include sore throat, pain on swallowing, fever, and headache, as well as tonsillopharyngeal erythema with or without exudates, anterior cervical lymphadenitis, soft palate petechiae, beefy red swollen uvula, and a scarlatiniform rash 1.
- Accurate differentiation of GAS pharyngitis from pharyngitis caused by other pathogens based on history and clinical findings is often difficult, and some form of microbiological confirmation, with either a throat culture or a rapid antigen detection test (RADT), is required for the diagnosis of GAS pharyngitis 1.
- For patients with penicillin allergies, alternatives include erythromycin or azithromycin, and supportive care is also important, including acetaminophen or ibuprofen for fever and pain, plenty of fluids to prevent dehydration, and rest 1.
- Patients should complete the full course of antibiotics even if symptoms improve to prevent complications like rheumatic fever or kidney inflammation, and most individuals are no longer contagious after 24 hours of antibiotic treatment and can typically return to school or work at this point, though full recovery may take a week or longer 1.
From the Research
Diagnosis of Scarlet Fever
- Scarlet fever is an infectious disease caused by group A streptococcal bacteria, and its diagnosis can be challenging due to diverse symptoms 2.
- The disease manifests as a sore throat, fever, and a sandpaper-like, papular skin rash, and it is essential to be aware of these symptoms to avoid the spread of the disease 2.
- A rapid streptococcal test or a throat culture should be performed to confirm the diagnosis of group A beta-hemolytic streptococcal pharyngitis, which is a common cause of scarlet fever 3.
Treatment Options for Scarlet Fever
- Early antibiotic therapy reduces the duration of pharyngitis, minimizes transmission, and lessens complications such as acute rheumatic fever and abscess 3.
- A 10-day course of oral penicillin or an intramuscular injection of penicillin G benzathine is recommended for the treatment of group A beta-hemolytic streptococcal pharyngitis 3, 4.
- Erythromycin is recommended for patients who are allergic to penicillin 3, 4.
- Prompt diagnosis and treatment are mandatory to reduce the mortality associated with invasive group A streptococcal infections and streptococcal toxic shock syndrome, which are rare complications of scarlet fever 5.
Prevention of Complications
- Primary prevention of acute rheumatic fever is accomplished by proper identification and adequate antibiotic treatment of group A beta-hemolytic streptococcal tonsillopharyngitis 4.
- Continuous antimicrobial prophylaxis is necessary to prevent recurrences of rheumatic fever in individuals who have had a previous attack 4.
- Penicillin is the agent of choice for secondary prophylaxis, but sulfadiazine or erythromycin are acceptable alternatives in penicillin-allergic individuals 4.