Jiro Sasaki

Descending necrotizing mediastinitis due to odontogenic infections

OBJECTIVE Acute purulent mediastinitis caused by oropharyngeal infection is termed descending necrotizing mediastinitis. Such infections usually have a fulminate course, leading to sepsis and frequently to death. The purpose of this study is to show the importance of early diagnosis, aggressive surgical intervention, and optimal antibiotics chemotherapy in controlling this fatal infectious disease. STUDY DESIGN Two patients with descending necrotizing mediastinitis due to odontogenic infection who were treated at our institution are described. RESULTS Both patients survived. CONCLUSIONS From the patients, 23 different aerobic and anaerobic bacteria were isolated. All of the isolates were susceptible to carbapenem. Early evaluation by means of cervicothoracic computed tomography scanning was extremely useful for diagnosis and surgical planning. Knowledge of anatomic pathways from the mouth to the mediastinum is essential. We believe that tracheostomy is not always necessary. In both of the cases presented, mediastinal drainage was completed through use of a transcervical approach. However, a more aggressive drainage including tracheostomy might be necessary when the infection extends below the carina.

Isolation of bacteria from cervical lymph nodes in patients with oral cancer

Thirty patients with oral mucosal cancer were studied in relation to oral mucosal damage and bacterial translocation to the regional lymph nodes in the neck. All 30 patients (gingiva 11, tongue 13, cheek mucosa four, oral floor two) underwent extensive, clean-contaminated, head-and-neck surgery (including neck dissection) with free flap reconstruction. A total of 153 lymph nodes was harvested for microbial and histological examination. Viable bacteria were isolated from 70 lymph nodes (45.8%) from 25 patients (83.3%). Bacterial cells in the nodes were detected by scanning electron microscopy. Bacterial translocation was found more often in metastatic nodes (75.0%) than in uninvolved nodes (40.3%) (p = 0.015; chi2 test). Gingival carcinoma yielded 56.4% of bacterial growth in the regional lymph nodes compared to tongue (40.3%), oral floor (40.0%) and cheek mucosa (37.5%). As the gingival carcinoma group includes more T4 cases (11/11; 100%) than the other three groups (7/19; 36.8%), bacterial translocation in uninvolved nodes could be caused by the size and invasion of the primary oral tumor. Oral streptococci (Streptococcus intermedius, Strep. constellatus, Strep. oralis, Strep. mitis, Strep. sanguis, Strep. salivarius) were the most common isolates. Aerobic enteric bacteria (Enterococcus, Escherichia, Klebsiella etc.) were also found in the lymph nodes. Among the anaerobic bacteria, Peptostreptococcus spp. were isolated from 12 patients. Damaged oral mucosa in patients with oral cancer might allow the new bacterial colonization on the surface and subsequently drain the bacteria into the regional lymph nodes as well as the general circulation.

Association between bacterial colonization on the tumor, bacterial translocation to the cervical lymph nodes and subsequent postoperative infection in patients with oral cancer

OBJECTIVE To investigate the association between postoperative infection, bacterial translocation to the cervical lymph nodes and bacterial colonization on the tumor in oral cancer patients. METHODS Twenty-one oral mucosal cancer patients (11 male and 10 females: mean age 68.6 years) were studied. They underwent tumor surgery and neck dissection with free flap reconstruction. Ampicillin 1 g was parenterally administered from the start of the surgery as prophylaxis. Isolates from cervical lymph nodes, tumor and postoperative infected wound were studied microbiologically and pathologically. RESULTS Bacterial translocation was found in 52 lymph nodes (52/107: 48.6%). Viable bacteria were isolated from 20 tumors (95.2%). Oral microflora and enteric bacteria were isolated. Postoperative infection was found in four cases. In three cases, enteric bacteria (Klebsiella, Enterobacter, Enterococcus) isolated from postoperative infections were also found in the tumor or the lymph nodes. CONCLUSIONS The operative field in oral cancer surgery was colonized by the indigenous flora and enteric bacteria. These were recovered not only from the tumor surface but also from the cervical lymph nodes. Preoperative surveillance culture or tumor culture have value in predicting the bacteriology of postoperative infection, and in selecting the appropriate antibiotic treatment.

Ga-67 scintigram in the diagnosis of infection of masticator muscles due to an odontogenic infection.

A 36-year-old man had a mandibular swelling and severe difficulty opening his mouth. His left lower wisdom tooth had been extracted 2 days before. He had a high fever (39°C), leukocytosis (9,300/ml), and an elevated C-reactive protein level (9.66 mg/ml). Ga-67 scintigraphy showed intense uptake in t