Sore throat is a common complaint from children and adolescents that often prompts physician visits. Many infectious agents are known to cause pharyngitis, and most require only supportive care. Two important causes of pharyngitis that should be recognized by clinicians are group A streptococcus (GAS, Streptococcus pyogenes) and EBV.

GAS pharyngitis occurs most commonly in school-aged children and accounts for 15% to 30% of all cases in children ages 5 to 15 years. The peak seasons for GAS pharyngitis are late fall, winter, and early spring. Classically, GAS pharyngitis has an abrupt onset and is associated with fever, headache, and abdominal pain. The common symptoms of viral upper respiratory infections, such as cough, rhinorrhea, and nasal congestion, are typically absent. Only 15% of patients will present with the classical constellation of signs and symptoms of acute pharyngitis with edema, erythema or exudates, and sometimes palatal petechiae and anterior cervical lymphadenopathy. Spontaneous resolution usually occurs in 3 to 5 days.

A throat culture is the gold standard method for the diagnosis of GAS pharyngitis. The throat culture, performed by sampling both tonsillar pillars and the posterior pharynx without touching the buccal mucosa or tongue, is incubated for at least 18 to 24 hours. Because of this delay, most physicians perform both a rapid antigen detection test and a throat culture. The specificity of the rapid test is very high, meaning that there are few false positives, but the sensitivity can be as low as 65%, which is why it is also imperative to send the throat culture to the laboratory. It is important to note that neither of these tests can distinguish between acute infection versus chronic carriage of GAS.