Clinical significance and outcome of Aeromonas spp. infections among 204 adult patients

The objectives of this investigation were to analyze the clinical patterns, risk groups, prognostic factors, and mortality of infections caused by Aeromonas spp. This was a retrospective study of adult patients with Aeromonas spp. isolates attended at the Hospital del Mar in Barcelona, Spain, between January 2006 and December 2012. Epidemiological data, antimicrobial susceptibility, clinical patterns, underlying illnesses, type of infection, admission to the intensive care unit (ICU), number of episodes, coinfection, antimicrobial therapy, and evolution were analyzed. A total of 221 clinical samples from 204 patients were positive for Aeromonas spp. The mean age of the patients was 67.6 years. The main clinical form of presentation was gastrointestinal (78.4%). Malignancy was the main risk group in 69 (33.8%) patients, and 48 (23.5%) were previously healthy. Twenty-one patients (10.3%) were admitted to the ICU. Infections were acquired in the hospital in 52.5% of the patients, and 28.9% were polymicrobial. The overall mortality (after 1 year of follow-up from the first positive culture) was 26.5%. Univariate analysis identified an association between increased mortality and the following variables: age ≥80 years, hospitalization, admission to the ICU, malignancy, extraintestinal infection, and appropriate antimicrobial therapy. In the multivariate analysis, age ≥80 years [odds ratio (OR), 4.37 [95% confidence interval (CI), 1.68–11.35; p = 0.002]], admission to the ICU (OR, 6.59 [95% CI, 2.17–19.99; p = 0.001]), and malignancy (OR, 3.62 [95% CI, 1.32–9.90; p = 0.012]) were significantly associated with mortality. Aeromonas infections are mainly gastrointestinal. The 1-year follow-up mortality rate was high. Old age (age ≥80 years), admission to the ICU, and malignancy were identified as independent risk factors for mortality.