[Clinical and bacteriological examination in hospital of Helicobacter cinaedi (H. cinaedi)]

The spiral Gram-negative bacterium Helicobacter cinaedi (H. cinaedi) is usually isolated from immunocompromized patients, and the number of patients in whom H. cinaedi is isolated from their blood culture is increasing in Japan. To elucidate why the number of cases is increasing, we tried to analyze separate cases of H. cinaedi. H. cinaedi was isolated from the blood culture of 24 cases, and the isolate was from the pleural effusion of 1 cases between September 2009 and March 2010. In our cases, H. cinaedi was frequently isolated after anticancer chemotherapies (44 isolates) and steroid therapies (42 isolates). The patients' clinical symptoms were fever (43 isolates), gastrointestinal symptoms (4 isolates) and skin symptoms (8 isolates). In all cases, the H. cinaedi growth was found only in an aerobic bottle, and it needed a long time (2-7 days) to grow. In 14 cases out of 25 cases, H. cinaedi bacteremia was recurred. We analyzed recurrent cases statistically. The result showed there was a significant difference between the kinds of quinolones (p = 0.0018). H. cinaedi infections have a good prognosis, but the infection tends to recur after anticancer chemotherapies. A report has suggested that the minimal inhibitory concentrations of quinolones increased is case of recurrence, we should pay attention to the use of antibacterial agents. Furthermore, the effective method to eliminate or prevert infection [recurrence] remains unknown. Our results show that H. cinaedi infections may prolong the duration of hospitalization. If H. cinaedi is isolated in a patient, it is necessary to set the culture conditions for H. cinaedi. Furthermore, there is a need for appropiate antibiotic selection and medication for H. cinaedi.