[Microbiological and clinical features of nine cases with nocardial infections].

Following recent advance in medical technology, the increase of immunocompromised patients results in an increase of opportunistic infections such as nocardiosis. However, little is known about relationships between clinical features of nocardial infections and each Nocardia species, especially newly identified ones. Therefore, we identified clinical isolates of Nocardia species by genetic methods and analyzed clinical features of nocardiosis. Nine clinical isolates were obtained in Kyushu University Hospital from 2005 to 2008. Six different Nocardia species were identified by 16Sr RNA: Nocardiafarcinia (n=2), Nocardia brasiliensis (n=2), Nocardia cyriacigeorgica (n=2), Nocardia transvalensis (n=1), Nocardia araoensis (n=1) and Nocardia testacea (n=1). The underlying diseases of 9 patients were pulmonary diseases(n=5), malignant diseases(n=3), collagen diseases(n=1) or primary immunodeficiency diseases (n=l). According to antimicrobial susceptibility testing, none of them was resistant to minocycline or linezolid. Among seven isolates from respiratory specimens, one was resistant to imipenem, sulfamethoxazole/trimethoprim and amikacin, two were to ciprofloxacin. Three species identified recently (N cyriacigeorgica, N. araoensis and N. testacea) were involved in this study and most of them were considered as infectious pathogens to human. These data suggested the identification of Nocardia to the species level and susceptibility testing were important for diagnosis as infectious diseases and treatments.