Neisseria mucosaによる細菌性心内膜炎の一例

抄録

A case of endocarditis due to Neisseria mucosa, the third case in the world, was reported.
Members of genus Neisseria, other than N. meningitidis and N. gonorrhoeae, are usually considerd to be nonpathogenic. However “nonpathogenic Neisseria” are known to cause serious diseases-endocarditis, meningitis and septicemia. Endocarditis due to Neisseria was first published by Kämmerer et al. in 1914, and thereafter 23 cases are reported in the literature; four due to N. flava, three to N. perflava, one to N. subflava, two to N. pharyngis, five to N. sicca, two to N. mucosa, three to N. catarrhalis and three to unclassified Neisseria.
Case: a 32 year old male with rheumatic heart disease (mitral stenoinsufficiency+aortic stenoinsufficiency) was admitted because of remittent fever and palpitation developed a few days after dental extraction. One of four blood cultures obtained on the first hospital day was positive. The organism was identified as Neisseria mucosa which is a normal inhabitant of human nasopharynx. It was suspected whether the organism was pathogene or not. On the high doses of Penicillin-G therapy, the fever was cleared after two days. In order to determine the pathogenicity of the isolate, Penicillin-G was stopped temporarily. On the next day after regimen stopped, high fever with shivering was reappeared. From all of four blood cultures taken at this time, N. mucosa was isolated again. Thus the pathogenicity of the isolate was confirmed. The organism was sensitive to Ampicillin, Carbenicillin, Penicillin-G, Cephaloridine, Chloramphenicol, Tetracycline, Streptomycin, Kanamycin, Gentamicin and Nalidixic acid, but resistent to Erythromycin, Oleandomycin, Josamycin and Lincomycin
After 6 weeks of combined therapy with Ampicillin, Kanamycin and Nalidixic acid, the patient was discharged, and observed no recurrence thereafter.