Erythematous pharynx, enlarged tonsils, and yellow-white exudate suggest infection with which organism?

• A. Group A Streptococcus
• B. Adenovirus
• C. Epstein-Barr Virus
• D. Group C Streptococcus

Answer: (D)

Erythematous pharynx with enlarged tonsils and yellow-white exudate is most classically seen with bacterial tonsillitis caused by Streptococcus pyogenes (Group A Streptococcus). This organism commonly produces a red throat, tender anterior cervical lymphadenopathy, fever, and tonsillar exudates. While viral causes like adenovirus can also produce a sore throat with exudates, they are typically accompanied by other viral symptoms such as conjunctivitis or rhinorrhea, and Epstein-Barr virus infection (mononucleosis) presents with marked fatigue and posterior cervical lymphadenopathy along with possible splenomegaly. Group C Streptococcus can cause pharyngitis too, but it is less commonly the source of this exudative presentation compared with Group A strep. In practice, this pattern most strongly points to Group A Streptococcus, and confirmation with a rapid strep test or throat culture guides treatment.