Antimicrobial susceptibility surveillance of bacterial isolates recovered in Japan from odontogenic infections in 2013.

We report on the findings of the first antimicrobial susceptibility surveillance study in Japan of isolates recovered from odontogenic infections. Of the 38 facilities where patients representing the 4 groups of odontogenic infections were seen, 102 samples were collected from cases of periodontitis (group 1), 6 samples from pericoronitis (group 2), 84 samples from jaw inflammation (group 3) and 54 samples from phlegmon of the jaw bone area (group 4) for a total of 246 samples. The positivity rates of bacterial growth on culture were 85.3%, 100%, 84% and 88.9%, respectively, for groups 1, 2, 3 and 4. Streptococcus spp. isolation rates according to odontogenic infection group were 22% (group 1), 17.7% (group 3) and 20.7% (group 4). Anaerobic isolation rates were 66.9% (group 1), 71.8% (group 3) and 68.2% (group 4). Drug susceptibility tests were performed on 726 strains excluding 121 strains that were undergrown. The breakdown of the strains subjected to testing was 186 Streptococcus spp., 179 anaerobic gram-positive cocci, 246 Prevotella spp., 27 Porphyromonas spp., and 88 Fusobacterium spp. The isolates were tested against 30 antimicrobial agents. Sensitivities to penicillins and cephems were good except for Prevotella spp. The low sensitivities of Prevotella spp is due to ß-lactamase production. Prevotella strains resistant to macrolides, quinolones, and clindamycin were found. No strains resistant to carbapenems or penems were found among all strains tested. No anaerobic bacterial strain was resistant to metronidazole. Antimicrobial susceptibility testing performed on the S. anginosus group and anaerobic bacteria, which are the major pathogens associated with odontogenic infections, showed low MIC90 values to the penicillins which are the first-line antimicrobial agents for odontogenic infections; however, for Prevotella spp., penicillins combined with ß-lactamase inhibitor showed low MIC90 values.

HIV-negative plasmablastic lymphoma attaining sustained remission with bortezomib-combined dose-adjusted EPOCH therapy.

A 61-year-old, HIV-negative, immunocompetent woman was admitted to our hospital for significant weight loss, painful swelling of her right cheek, and rapid growth of a tumor in the right hard palate. A CT scan revealed a neoplastic lesion in the right maxillary sinus, extending to the surrounding soft bone tissue and oral cavity, as well as multiple osteolytic lesions in the skull. A pathologic examination revealed that the neoplastic cells in the oral cavity were plasmablasts tending to appear as differentiated plasma cells. The tumor cells strongly expressed CD138, Vs38c, EBER, and MYC, and were negative for CD20 and CD19. The MIB-1 index was 90%, and MYC/IgH fusion gene was detected by fluorescence in situ hybridization analysis. Based on these clinical and pathological findings, we confirmed the diagnosis of plasmablastic lymphoma. This disease has characteristics of aggressive lymphoma originating from differentiated plasma cells. Treatment was initiated with dose-adjusted EPOCH added to a concurrent bortezomib regimen. After completion of four cycles, the patient achieved and sustained complete remission.

[Reinforcement of warfarin action in a patient administered S-1].

A case showing reinforcement of the action of warfarin and potassium in a patient administered S-1 is reported.The patient was a 71-year-old man with left upper gingival cancer.He had ventricular tachycardia (VT), hypertrophic cardiomyopathy, and a cerebellar infarction.He underwent a pacemaker implantation, and was administered warfarin.After the operation, in mid-March 2010, he was administered with S-1 and warfarin. However, the international normalized ratio of prothrombin time (PT-INR) increased to an extremely high level of 5.82, and S-1 and warfarin were stopped. They were re-administered at the end of April, and the PT-INR stabilized to approximately 2.