From the Research
Management of Aeromonas bacteremia requires prompt antibiotic therapy with fluoroquinolones or third-generation cephalosporins as first-line treatments, with ciprofloxacin (400mg IV every 12 hours) or ceftriaxone (1-2g IV every 24 hours) typically recommended for initial empiric therapy. The choice of empiric therapy has become increasingly difficult due to the increasing incidence of antibiotic-resistant bacteria 1.
Key Considerations
- Treatment duration should be 10-14 days for uncomplicated bacteremia, extending to 2-3 weeks for patients with immunosuppression or metastatic infections.
- Source control is essential, including removal of infected catheters or drainage of abscesses if present.
- Combination therapy may be considered for severe infections, typically adding an aminoglycoside such as gentamicin (5-7mg/kg/day).
- Susceptibility testing should guide definitive therapy, as resistance patterns vary among Aeromonas species.
- Carbapenems (meropenem 1g IV every 8 hours) may be used for resistant strains, as they have a broad spectrum of in vitro activity against Gram-positive and Gram-negative pathogens, including extended-spectrum beta-lactamase (ESBL)- and AmpC-producing Enterobacteriaceae 2.
Resistance Patterns
- Aeromonas species can produce various toxins and enzymes that contribute to their virulence and potential for causing severe systemic infections.
- The activity of amoxycillin/clavulanate and the acylureidopenicillins is inconsistent, while aztreonam and the carbapenems, imipenem and meropenem remain highly active 3.
- There is growing evidence that inadequate or prolonged antibiotic administration may encourage the emergence of resistant bacteria 1.
Monitoring and Follow-up
- Patients require close monitoring for clinical improvement within 48-72 hours, with follow-up blood cultures to confirm clearance of bacteremia.
- Aeromonas infections often occur following exposure to contaminated water or in immunocompromised hosts, with A. hydrophila, A. caviae, and A. veronii being the most common species causing human infections.
The most recent and highest quality study 4 provides guidance on the management of Pseudomonas aeruginosa infections, which can inform the treatment of Aeromonas bacteremia. However, the specific treatment of Aeromonas bacteremia should be guided by the most recent and relevant evidence, with a focus on reducing morbidity, mortality, and improving quality of life.