What is the treatment for Salmonellosis (Salmonella infection)?

From the Guidelines

Salmonella infection typically resolves on its own within 4-7 days with supportive care at home, and antibiotics are usually not necessary unless the infection is severe or the patient is at high risk. The most important treatment is maintaining hydration by drinking plenty of fluids like water, clear broths, or oral rehydration solutions such as Pedialyte to replace lost fluids and electrolytes. Over-the-counter medications like acetaminophen (Tylenol) or ibuprofen (Advil) can help manage fever and pain. Avoid anti-diarrheal medications like loperamide (Imodium) as they can prolong the infection by preventing bacteria from being expelled. Most cases don't require antibiotics, but they may be prescribed for severe infections, particularly in high-risk individuals (young children, older adults, pregnant women, or immunocompromised people). Common antibiotics used include ciprofloxacin, azithromycin, or trimethoprim-sulfamethoxazole for 5-7 days, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea 1. Seek medical attention if you experience high fever (over 102°F), bloody stools, severe vomiting, signs of dehydration (extreme thirst, dry mouth, minimal urination), or symptoms lasting more than a week. Salmonella spreads through contaminated food or water, so practicing good hygiene and food safety is essential to prevent reinfection or transmission to others. Some studies suggest that fluoroquinolones, such as ciprofloxacin, are effective in treating salmonellosis, especially in immunocompromised patients 1. However, the use of antibiotics should be cautious and based on the severity of the infection and the patient's risk factors, as recommended by the guidelines 1. In general, the treatment of salmonella infection should focus on supportive care and hydration, with antibiotics reserved for severe or high-risk cases.

From the Research

Treatment Options for Salmonella

• Antimicrobial therapy is usually initiated before the in vitro susceptibility tests of the isolate become available 2
• The drugs of choice for empiric treatment of acute infectious diarrhea, in which Salmonella spp are etiologically implicated, are fluoroquinolones in adults and third generation cephalosporins in children 2
• Alternative treatment may use azithromycin and imipenem in life-threatening systemic Salmonella infections 2
• Aminoglycosides are considered ineffective in gastrointestinal salmonelloses 2

Antibiotic Resistance

• The emerging resistance to fluoroquinolones, production of extended-spectrum beta-lactamases, and the increase of multidrug resistant Salmonella strains are major problems in the search for efficient antimicrobial therapy of Salmonella infection 2
• Ciprofloxacin resistance is rarely seen in non-typhoid Salmonella enterica isolates, and only in S. Typhimurium, S. Choleraesuis and S. Schwarzengrund 3
• Azithromycin at a dose of 500mg daily is an effective treatment for fully sensitive strains of S. Typhi but is associated with delayed treatment response and prolonged bacteraemia when compared with ciprofloxacin 4

Treatment Response

• Treatment with azithromycin was associated with prolonged bacteraemia and prolonged fever clearance times compared to ciprofloxacin 4
• A prolonged treatment response was observed significantly more frequently in the azithromycin group compared to the ciprofloxacin group 4
• The observed systemic plasma concentrations of azithromycin did not exceed the minimum inhibitory concentration (MIC), whilst predicted intracellular concentrations did exceed the MIC 4

Fluoroquinolone Susceptibility Testing

• Fluoroquinolone resistance in Salmonella is mostly due to mutations in the topoisomerase genes, but plasmid-mediated quinolone resistance (PMQR) mechanisms have also been described 5
• The new levofloxacin MIC breakpoints resulted in the highest category agreement when plotted against the ciprofloxacin MICs 5
• The new ofloxacin MIC breakpoints resulted in 92% category agreement between ofloxacin and ciprofloxacin 5