สถาบันวิจัยวิทยาศาสตร์สาธารณสุข

NATIONAL INSTITUTE OF HEALTH OF THAILAND

Nocardia beijingensis, is a pathogenic bacterium to humans: the first infectious cases in Thailand and Japan

Authors : Akiko Kageyama*, Natteewan Poonwan**, Katsukiyo Yazawa*, Yuzuru Mikami*, Kazuko Nishimura*

 

Affiliations:     *Research Center for Pathogenic Fungi and Microbial Toxicoses, Chiba
                        University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan
                        **Mycology Section, National Institute of Health, Department of Medical 
                        Sciences, Nonthaburi, Thailand

Source:
            Mycopathologia 2004; 157(2): 155-61
 
Language:     English

Abstract:
 
Nocardia beijingensis, a recently established new species, is an isolate from soil in China. During our taxonomic studies on 450 nocardial clinical isolates in Thailand and Japan, 17 strains from Thailand and 1 strain from Japan were found to have a similar physiological characteristic to those of N. beijingensis, such as a drug susceptibility pattern to three antimicrobial agents. Our phylogenetic studies on these 18 strains by 16S rRNA gene sequence analysis confirmed that these strains belong to N. beijingensis species. Phylogenetically, these newly isolated N. beijingensis strains were found to be classified into two distinct clades: one is a Japanese clade and other is a Chinese clade, including a reference strain and 17 Thai strains. This is the first report of human infection due to N. beijingensis strains, and we propose that the bacterium be categorized as an opportunistic infectious group regardless of its original isolation from soil.