3.24 Salmonella Species

Microbiology review for the USMLE Step 1 Exam

• Salmonella are gram-negative bacteria that cause gastrointestinal disease.
• They have flagella that enable them to move around and infect cells, and can live inside macrophages.
• There are two categories of salmonella species: typhoidal and non-typhoidal.
• Typhoidal salmonella, such as salmonella typhi, cause typhoid fever and are usually acquired through contaminated water.
• Non-typhoidal salmonella, such as salmonella enteritidis, are usually acquired through contaminated poultry or reptiles.
• Typhoidal salmonella cause high fever and a pink spotted rash, while non-typhoidal salmonella cause diarrhea, nausea, and vomiting.
• Both types of salmonella require large quantities of bacteria to make you sick, and supportive care is usually all that is required.
• Fluoroquinolones like ciprofloxacin are the go-to antibiotics for typhoidal salmonella.