Appearance of fosfomycin resistant Rahnella aquatilis clinically isolated in Japan

Among recent clinical isolates in Japan, strain CU264 was discovered which formed unusual colonies. This strain was identified as Rahnella aquatilis w hich is usually found in water. The antibiotic susceptibilities against tet racycline, carbenicillin, chloramphenicol, streptomycin, kanamycin, gentami cin, sulphonamide, neomycin, fosfomycin, rifampicin, norfloxacin and nalidi xic acid, were investigated. The result demonstrated that the strain was hi ghly resistant to fosfomycin only. It was further shown that this resistanc e was transmissible with low frequency to Serratia marcescens whereas it wa s not transmissible to Escherichia coli.