Treatment of Salmonella Bacteremia
The recommended first-line treatment for Salmonella bacteremia is ciprofloxacin, typically administered at 500 mg twice daily for at least 14 days. 1
First-Line Treatment Options
- Ciprofloxacin is the preferred fluoroquinolone for treating Salmonella bacteremia in adults 2, 3
- For severe infections or in immunocompromised patients, initial combination therapy with ceftriaxone (2 g once daily IV) plus ciprofloxacin is recommended until susceptibility results are available 1
- After susceptibility testing, therapy can be de-escalated to a single appropriate agent based on results 1
Alternative Treatment Options
- Trimethoprim-sulfamethoxazole (TMP-SMX) can be used if the organism is susceptible 2, 3
- Expanded spectrum cephalosporins (e.g., ceftriaxone or cefotaxime) are effective alternatives based on susceptibility testing 2
- Amoxicillin can be used if susceptibility is confirmed 1
Treatment Duration
- For immunocompetent patients with bacteremia: minimum 14 days of treatment 1, 4
- For immunocompromised patients with advanced HIV disease (CD4+ count <200 cells/μL): extended course of 2-6 weeks 2, 3
- Patients with Salmonella bacteremia should be treated for >2 weeks, and adding a second active agent (e.g., an aminoglycoside) might be prudent in severe cases 2
Special Populations
Immunocompromised Patients
- HIV-infected patients and other immunocompromised individuals should always receive treatment for Salmonella infections due to high risk of bacteremia 2, 3
- For persons with recurrent Salmonella septicemia, 6 months or more of antibiotics treatment should be considered as secondary prophylaxis 2
- Long-term suppressive therapy with ciprofloxacin (500 mg twice daily) for at least 2 months may be needed to prevent recurrence in HIV-infected patients 1
Children
- Fluoroquinolones should be used with caution in children under 18 years and only if no alternatives exist 3, 5
- Preferred options for children include TMP-SMX, ampicillin, cefotaxime, or ceftriaxone 3, 5
- A recent study suggests that shorter courses (<7 days) of IV antibiotics may be noninferior to longer courses (≥7 days) in otherwise healthy children 6
Pregnant Women
- Fluoroquinolones should be avoided during pregnancy if possible 2, 3
- Recommended alternatives include ampicillin, cefotaxime, ceftriaxone, or TMP-SMX 2, 3
- Despite theoretical concerns, approximately 400 cases of quinolone use in pregnancy have not shown association with arthropathy or birth defects 2
Monitoring and Follow-up
- Patients should be monitored closely for response to treatment, defined by improvement in systemic signs and symptoms 2
- Some patients with Salmonella bacteremia might remain febrile for 5-7 days despite effective therapy 2
- Follow-up blood cultures are not routinely required if clinical improvement is observed 2
Management of Treatment Failure
- Treatment failure is defined by lack of improvement in clinical signs and symptoms and persistence of organisms in blood after completion of appropriate antimicrobial therapy 2
- If treatment failure occurs, antibiotic therapy should be guided by drug susceptibility testing 2
- Evaluate for other factors that might contribute to failure or relapse, such as malabsorption of oral antibiotics, a sequestered focus of infection, or adverse drug reactions 2
Prevention of Recurrence
- HIV-infected persons with Salmonella septicemia should be monitored clinically for recurrence after treatment 2
- Household contacts of persons with salmonellosis should be evaluated for persistent asymptomatic carriage to prevent recurrent transmission 2
Emerging Concerns
- Increasing resistance to fluoroquinolones makes the choice of therapy especially problematic in some regions 2, 7
- The emergence of extended-spectrum beta-lactamase-producing strains and multidrug-resistant Salmonella are major challenges in treatment 7
- Susceptibility testing should guide final antibiotic selection whenever possible 2, 3