In the case of severe Shigella infection, what is the first-line treatment?

In the case of severe Shigella infection, the first-line treatment is trimethoprim-sulfamethoxazole. This antibiotic combination provides effective coverage against Shigella species, which are known to cause dysentery characterized by diarrhea, fever, and abdominal cramps. Trimethoprim-sulfamethoxazole works by inhibiting bacterial folate synthesis, making it particularly effective against a variety of gram-negative bacteria, including those responsible for Shigella infections.

Though fluoroquinolones and ceftriaxone are also effective against Shigella, trimethoprim-sulfamethoxazole is often preferred, especially in pediatric cases, due to its widespread use and established effectiveness. Additionally, rehydration therapy is critical to managing diarrhea and preventing dehydration, but it does not address the underlying bacterial infection directly, which is why antibacterial treatment remains essential in severe cases of Shigella.