Experience with Invasive Aeromonas Infections at a Rural Hospital in the United States of America

Abstract

Introduction:

Aeromonas spp. are important human pathogens causing enteric disease or invasive infections commonly involving skin and soft tissue, biliary system, blood stream, and lung following aspiration. Only limited data regarding Aeromonas spp. infections from the United States are available.

Patients and Methods:

This is a retrospective analysis of all infections caused by Aeromoas spp. during a four-year period at a rural hospital in the Appalachian region. Data were retrieved from electronic medical records, including the microbiology database.

Results:

Between 10/2018 and 12/2022, 26 isolates of Aeromonas spp. in 21 patients (14 m/7 f) with a median age of 56 (range 0.1–86) years were identified. Six isolates were from blood cultures (four associated with biliary infections); 14 patients had soft-tissue infections, and one had acute cholecystitis. There were 18 A. hydrophila/A. caviae isolates, two specimens grew A. sobria, and one A. veronii. In 10 cases, Aeromonas spp. was the only isolated organism; 11 infections (52%) were polymicrobial. Isolated co-pathogens were gram-positive cocci (6), gram-negative rods (6), and anaerobes (2). Nine patients underwent interventions (n = 10), including wound debridement (3), endoscopic retrograde cholangiopancreatography (ERCP) (3), percutaneous cholecystostomy (2), and laparoscopic cholecystectomy (2). Preferred antibiotics were fluoroquinolones (5), 3^rd/4^th generation cephalosporins (5), trimethoprim/sulfamethoxazole (TMPS) (2), and doxycycline (2). All infections were successfully treated, and all patients are currently alive except one, who died from metastatic pancreatic cancer.

Conclusion:

Aeromonas spp. are rare clinical pathogens but are capable of causing severe infections. Most patients in this series had surgical infections. Surgeons need to be aware that the organism has a propensity for causing biliary infections.