Group A streptococcal infections.

• GAS is a common cause of upper respiratory tract and skin infections.• Based on strong research evidence, (1) throat culture is the gold standard for diagnosing GAS pharyngitis.• Based on strong research evidence, (1) oral penicillin V K is the antibiotic treatment of choice for GAS pharyngitis because of its efficacy, safety, and narrow spectrum.• Based on strong research evidence, (2) primary prevention of complications of GAS such as ARF involves prompt diagnosis and antibiotic treatment of GAS pharyngitis.• GAS nonsuppurative and suppurative complications may occur and are mediated by interactions between GAS antigens or exotoxins and the patient’s immunesystem.