Analysis of antibiotic resistant infections associated with hirudotherapy

Given rising concern regarding antibiotic resistance, our objective was to evaluate antibiotic-resistant infections following leech therapy and to characterize the use of prophylactic antibiotics.

All reports of adverse events involving hirudotherapy (product code "NRN") were retrieved from the U.S. Food and Drug Administration MAUDE database between 2012 and 2021. Antibiotic resistance was defined by bacterial culture or infection after antibiotic administration.

Nineteen cases of antibiotic resistance involving hirudotherapy were identified. Only three cases of antibiotic resistance were discovered on routine testing and the remaining 16 cases were associated with patient injury. Positive blood cultures or fever were present in 26.3 % (n = 5) of cases. Cultures of the infection grew Aeromonas hydrophilia (n = 13; 68.4 %), Vibrio vulnificus (n = 3; 15.8 %), Pseudomonas aeruginosa (n = 2; 10.5 %), and Proteus vulgaris (n = 1; 5.3 %). There were nine (47.4 %) multi-drug resistant infections. Infection was most commonly resistant to fluoroquinolones (n = 9; 47.4 %), trimethoprim-sulfamethoxazole (n = 9; 47.4 %) and ertapenem (n = 4; 21.1 %).

Antibiotic-resistant infections involving hirudotherapy are frequently resistant to multiple drugs, including fluoroquinolones and trimethoprim-sulfamethoxazole. Resistance to ertapenem, a drug of last resort, was also documented. The findings presented in this study support growing literature that the trend in multi-drug resistance is more severe than previously reported.