Bacillus simplex as the Most Probable Culprit of Penetrating Trauma Infection: A Case Report

Bacillus simplex is an environmental microorganism found in soil. Herein, we present the case of a 69-year-old Greek male patient who attended the Emergency Department at our hospital. The patient complained of lower right extremity swelling and pain, after suffering penetrating trauma whilst doing farm work in a rural area. Swab aerobic cultures revealed Bacillus simplex as identified by MALDI-TOF Mass Spectrometry. The strain was susceptible to vancomycin, imipenem, clindamycin, and ciprofloxacin. Our patient refused hospitalization; therefore, both ciprofloxacin and clindamycin were registered for a total of 19 days. No complications were experienced, and he recovered fully. In our case, the thorough cleaning of the ulcer bed prior to sample collection, the fact that it was the only microorganism isolated, and the wound's aggravating mechanism led the authors of the present study to the conclusion that B. simplex was the most probable culprit of the infection. To our knowledge, this is the second probable case of B. simplex infection described worldwide, and the first in Greece.