Leuconostoc pseudomesenteroides Bacteremiae in a Patient with Malignancy: A Case Report

Leuconostoc spp. are members of Streptococcus family that can be found in plants and dairy products as well as in feces and vaginal flora of humans. Unlike other streptococci, they have intrinsic resistance to vancomycin. Although it is a very rare pathogen of humans, it may cause serious infections, especially in immunocompromised hosts. In this paper, we present a case of soft tissue infection with bacteremia caused by Leuconostoc pseudomesenteroides that was cured with daptomycin. A forty-year-old obese woman was admitted with fever and cellulitis of right arm. She had a history of invasive ductal carcinoma operation on her right breast and chronic right arm lymphedema. Piperacillin-tazobactam was initiated. After 48 hours, the clinical findings did not improve and teicoplanin was added to the therapy. At the 72th hour, fever continued, cellulitis spread to the chest wall and bullous lesions appeared on the right hand. The treatment was switched to daptomycin. Leuconostoc pseudomesenteroides was isolated in blood cultures of the patient. It was susceptible to linezolid, ampicillin minimum inhibitory concentration (MIC=2), ciprofloxacin (MIC