Eubacterium limosum: an elusive pathogen causing surgical infections

Authors:
Aaron George, Hugo Bonatti, Pooja Ajith

Body of Abstract:
Background: Eubacterium limosum is an anaerobic bacterium colonizing the human intestinal flora. Thus far less than 10 cases of infections due to the organism have been reported.
Methods: Following an index case of a 21-year-old female, who underwent laparoscopic drainage of an intraabdominal abscess associated with a lost fecalith after perforated appendicitis three months earlier, in which Eubacterium limosum was isolated (figure 1), our institutional database was searched for all cases of infections during a 4-year period caused by the unusual pathogen.
Results: Seven patients (3m/4f) including the index case with infections caused by Eubacterium limosum were identified. Median age was 62.4 (range 21.4 to 86.3) years, median body mass index was 33.0 (range 25.2 to 46.4) kg/m2. COPD rate was 29% with one third being active smokers. One patient had urosepsis and one had ankle osteomyelitis, the remaining 5 patients had intraabdominal infections associated with perforated appendicitis (2), retained fecalith (1), diverticulitis (1) and ileostomy revision. The urosepsis was monomicrobial all other were polymicrobial. Isolated co-pathogens in the six polymicrobial infections included Staphylococcus aureus (MRSA) 2, Enterococcus faecium (VRE) 1, Escherichia coli 2, Eikenella corrodens 1, Bacteroides eggerthii 1, Parabacteroides distatonis 3, Prevotella loescheii 1 and Bacillus species 1. All infections were successfully managed with surgical source control and antibiotics.
Conclusion: Eubacterium limosum is an extremely rare pathogens but capable of causing serious infections in humans. In our setting, intraabdominal infection was the most common presentation.