Multidrug resistant Aeromonas infection following medical leech therapy: A case report and development of a joint antimicrobial stewardship and infection prevention protocol.

OBJECTIVE: Aeromonas sp. infections are a recognized complication of medical leech therapy (MLT). In patients requiring MLT, ciprofloxacin or trimethoprim-sulphamethoxazole are commonly used to prevent such nosocomial infections. After a patient at our institution developed a MLT-associated multi-drug resistant (MDR) Aeromonas infection, we developed and evaluated a joint antimicrobial stewardship and infection prevention protocol for MLT at our institution. METHODS: We describe a case of a surgical site infection with MDR Aeromonas following MLT that was resistant to typically prescribed prophylactic antimicrobials, and development of a new leech culture protocol to proactively monitor for antimicrobial resistance among our institution's leech supply. We also report the rates of MLT-associated infections prior to and following implementation of this protocol and the antimicrobial susceptibility profiles detected in leech culture at our institution. RESULTS: Between October 2014 and February 2018, 46 patients received MLT at our institution. Other than the case described in this report, no other instances of MLT-related infections were noted during this time period. Culture results from 22 leeches in six batches since February 2018 showed that all were susceptible to ciprofloxacin, TMP-SMX, and ceftriaxone. Since initiation of a leech culture protocol, no further cases of MLT-associated infections have been reported at our institution. CONCLUSIONS: In light of increasing antimicrobial resistance and the potentially devastating consequences of MLT-associated infections, institutions offering MLT should be aware of these risks and ensure that protocols are in place to minimize infection risks for patients.

Relapse versus Reinfection of Mycobacterium avium Complex Pulmonary Disease. Patient Characteristics and Macrolide Susceptibility.

RATIONALE: Clinical recurrence of Mycobacterium avium complex (MAC) pulmonary disease occurs in 10 to 40% of patients treated for this disease process. Episodes of clinical recurrence may represent true relapse from the same MAC strain or reinfection with a new strain. OBJECTIVES: The purpose of this study was to investigate the clinical implications of separating patients into these two groups. METHODS: This retrospective study evaluated patients with a clinical recurrence of MAC pulmonary disease at our institution from 2000 to 2012. Isolates were genotyped using pulsed-field gel electrophoresis to differentiate relapse versus reinfection. Change in macrolide susceptibility was also analyzed. MEASUREMENTS AND MAIN RESULTS: In our cohort, 25% of patients suffered a clinical recurrence. Of the 46 included patients, 25 (54%) suffered a true relapse and 21 (46%) had a reinfection. Median time between completion of therapy and clinical recurrence was significantly lower in the relapse group compared with the reinfection group (210 d vs. 671 d; P = 0.004). The measured convalescent macrolide minimum inhibitory concentrations were significantly more likely to increase in the relapse group compared with the reinfection group (80 vs. 33%; P = 0.002). No differences in clinical outcomes were observed between the two groups at conclusion of the study. CONCLUSIONS: Our findings suggest that patients with true relapse of MAC pulmonary disease present earlier than those with reinfection. Routine use of pulsed-field gel electrophoresis in the management of clinical recurrences may be beneficial, as those suffering a relapse are more likely to have increasing macrolide minimum inhibitory concentrations than those with reinfection.