Open Access Case report

Descending necrotizing mediastinitis associated with Lactobacillus plantarum

Takahito Nei16*, Shunta Inai2, Iwao Mikami3, Akira Sato3, Junichi Okamoto3, Kazuhiko Yokoshima2, Munenaga Nakamizo2, Shuji Haraguchi3, Kazunari Sonobe4 and Ryoichi Saito5

Author Affiliations

1 Department of Infection Control and Prevention, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan

2 Department of Otorhinolaryngology, Head and Neck Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan

3 Department of Surgery (Division of Thoracic Surgery), Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan

4 Department of Clinical Laboratory, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan

5 Department of Microbiology and Immunology, Tokyo Medical and Dental University, 1-5-45, Yushima, Bukyo-ku, Tokyo 113-8510, Japan

6 Department of Internal Medicine (Division of Respiratory, Medicine, Infection and Oncology), 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan

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BMC Infectious Diseases 2013, 13:398  doi:10.1186/1471-2334-13-398

Published: 29 August 2013



Descending necrotizing mediastinitis (DNM), a severe infection with a high fatality rate, develops in mediastinal spaces due mainly to deep cervical abscesses. The majority of causative microbes of DNM are Streptococci and oral anaerobes. DNM associated with Lactobacillus-infection is rather rare.

Case presentation

A 69-year-old male with an unremarkable past medical history was referred to our hospital for surgical resection of advanced laryngeal cancer. Full examination revealed a neck abscess and DNM with a background of untreated diabetes mellitus. Initially, he was treated with meropenem. However, Lactobacillus plantarum was isolated from surgical drainage of a mediastinal abscess. Despite using antibiotics capable of eradicating all isolates with susceptibilities not differing significantly from those of the neck and mediastinal abscesses, we attributed DNM to the L. plantarum detected only in the mediastinal abscess. After DNM treatment, he underwent total pharyngolaryngectomy with bilateral neck dissection followed by reconstruction using free jejunum. He was discharged fully recovered.


We concluded that L. plantarum as the sole cause of the mediastinal abscess in the present case cannot be ruled out. As the number of immunocompromised patients increases, we should be cautious regarding this “familiar” microbe.

Descending necrotizing mediastinitis (DNM); Laryngeal cancer; Thoracoscopic surgery; Lactobacilli