Streptococcal Pharyngitis

A 22-year-old university student presents with a 2-day history of sore throat, fever, and tender anterior cervical lymphadenopathy. On examination, there is marked tonsillar erythema with exudates, but the patient denies any cough. 

A rapid antigen detection test for group A Streptococcus is positive.

Question:
What is the most appropriate first-line treatment for this patient?

A) Amoxicillin
B) Bactrim (trimethoprim-sulfamethoxazole)
C) Ciprofloxacin
D) Cephalexin

Correct Answer:

A) Amoxicillin

Explanation of the Correct Answer:
Amoxicillin is the preferred first-line treatment for streptococcal pharyngitis. It is effective, well-tolerated, and typically more palatable than some other options, ensuring better adherence to the prescribed course. Its targeted activity against Group A Streptococcus makes it the standard of care in this setting.

Why the Other Options Are Incorrect:

• B) Bactrim (trimethoprim-sulfamethoxazole): Bactrim does not provide reliable coverage for Group A Streptococcus. Although it is useful for certain gram-negative and staphylococcal infections, it is generally not effective for streptococcal pharyngitis and is not recommended.
• C) Ciprofloxacin: Ciprofloxacin’s spectrum is primarily directed against gram-negative pathogens and atypical bacteria. Its coverage of gram-positive organisms, including Group A Streptococcus, is poor, making it a poor choice for treating streptococcal pharyngitis. Additionally, fluoroquinolones are not recommended due to their broader spectrum and the risk of adverse events and resistance development when more targeted therapies exist.
• D) Cephalexin: While cephalexin does have activity against Group A Streptococcus, it is not the first-line choice. Narrow-spectrum beta-lactams like amoxicillin are preferred for their proven efficacy, safety, and reduced impact on the patient’s microbiota.