What is a primary treatment option for Legionella pneumonia?

• A. Doxycycline
• B. Azithromycin
• C. Amoxicillin
• D. Penicillin G

Answer: (B)

Legionella pneumonia requires an antibiotic that can reach and act inside cells, because Legionella lives inside macrophages and other lung cells. Macrolides like azithromycin achieve high intracellular concentrations and effectively kill Legionella, making them a preferred treatment. Doxycycline can treat some atypical pneumonias, but its activity against Legionella is less reliable here, so it isn’t the first choice. Amoxicillin and Penicillin G don’t penetrate well into cells where Legionella hides and aren’t effective against this pathogen. For these reasons, azithromycin is the best option among the choices. (Note: fluoroquinolones are also effective and used in some cases, but the given best choice is azithromycin.)