Transferable antibiotic resistance in nosocomial Stenotrophomonas maltophilia strain.

Stenotrophomonas maltophilia (298/85) was isolated from the extensively inflamed conjunctiva of a neonate in a regional hospital in Ostrava, Czech Republic. It was resistant to all available antibiotics except cefepime and trimethoprim. The donor S. maltophilia strain 298/85 transferred carbenicillin and cephaloridine resistance determinants to recipient strains of Escherichia coli K-12 3110 rif+ and Proteus mirabilis P-38 rif+. All transconjugant colonies were co-resistant also to kanamycin, cefotaxime, and aztreonam. Active hydrolysis of imipenem in the original strain was inhibited by ethylene diamine tetra-acetic acid, and hydrolysis of cefotaxime and aztreonam in the original strain and in the E. coli K-12 transconjugant was inhibited by clavulanate. In contrast, ceftazidime was hydrolyzed by the original strain and was not inhibited by clavulanate, indicating a different character of the resistance to cefotaxime or aztreonam and ceftazidime.