Notes from the Field: Group A Streptococcal Pharyngitis Misdiagnoses at a Rural Urgent-Care Clinic--Wyoming, March 2015.

Group A Streptococcus (GAS) is the most common bacterial cause of pharyngitis, implicated in 20%-30% of pediatric and 5%-15% of adult health care visits for sore throat (1). Along with the sudden onset of throat pain, GAS pharyngitis symptoms include fever, headache, and bilateral tender cervical lymphadenopathy (1,2). Accurate diagnosis and management of GAS pharyngitis is critical for limiting antibiotic overuse and preventing rheumatic fever (2), but distinguishing between GAS and viral pharyngitis clinically is challenging (1). Guidelines for diagnosis and management of GAS pharyngitis have been published by the Infectious Diseases Society of America (IDSA)* (1). IDSA recommends that patients with sore throat be tested for GAS to distinguish between GAS and viral pharyngitis; however, IDSA emphasizes the use of selective testing based on clinical symptoms and signs to avoid identifying GAS carriers rather than acute GAS infections (1). Therefore, testing for GAS usually is not recommended for the following: patients with sore throat and accompanying symptoms (e.g., cough, rhinorrhea) that strongly suggest a viral etiology; children aged <3 years, because acute rheumatic fever is extremely rare in this age group; and asymptomatic household contacts of patients with GAS pharyngitis (1). IDSA recommends penicillin or amoxicillin as the treatment of choice based on effectiveness and narrow spectrum of activity. To date, penicillin-resistant GAS has never been documented (1).