Environmental factors associated with etiology of microbiologically confirmed reconstructive breast implant infections: impact on clinical management and treatment.

Even if wide differences exist in the incidence of Gram-negative infections following breast cancer implant reconstructions (2-20%), its occurrence needs to be considered to optimize antibiotic therapy, which is usually directed towards Gram-positive cocci. There is a general notion on the possible source of Gram-negative microorganisms during outdoor activities. For this reason, we administered a specific questionnaire to infected patients to investigate this aspect. In 450 consecutive implant reconstructions between January 1, 2016 and March 31, 2018, 27 patients (6%) developed proven infection. For each patient, we collected age, tumor stage and recurrence, chemo/radiotherapy, infecting microorganism, fate of implant, type and duration of antibiotic treatment, and administered a questionnaire on exposure to contaminated environments. Twenty patients (74%) had Gram-positive and 7 (26%) had implants infected by Gram-negative agents. The two groups were homogeneous as regards age and no statistically significant difference was observed for other parameters. A significant difference was detected with regard to environmental risk factors in the Gram-negative group (p=0,049). Length of antibiotic therapy was longer in the Gram-negative patients (17.4 vs 11.05 days) and antibiotic treatment was ineffective in 43% of the Gram-negative group. Environmental factors may be an element to evaluate in order to improve patient management. Surveys on larger cohorts are warranted.