REPORT OF INVASIVE RHODOCOCCUS-EQUI INFECTIONS IN TAIWAN, WITH AN EMPHASIS ON THE EMERGENCE OF MULTIDRUG-RESISTANT STRAINS

From November 1995 to October 1997, seven patients with invasive infec tions due to Rhodococcus equi were treated in Taiwan. Four patients ha d pulmonary lesions, and one each of the remaining three patients had a recurrent Port-A-Cath (Kabi-Pharmacia, North Ryde, New South Wales, Australia)-related bacteremia, a primary bacteremia, and a brain absce ss. Three patients had underlying hematologic malignancies, and one ea ch of the remaining four patients had diabetes mellitus, Waldenstrom's macroglobulinemia, long-term use of steroids, and AIDS. The 13 isolat es of R. equi recovered from these patients were identified by using A PI Coryne System (bioMerieux, Marcy l'Etoile, France), VITEK GPI card (bioMerieux Vitek, Hazelwood, MO), supplemental biochemical tests, and cellular fatty acid chromatograms. Susceptibilities of these isolates to 16 antimicrobial agents, with use of the agar dilution method, var ied; among them, amikacin and trimethoprim-sulfamethoxazole were the m ost active agents. Different random amplified polymorphic DNA (RAPD) p atterns of isolates from different patients documented the lack of epi demiological relatedness of the causative organisms of these infection s. This study confirms the emergence of multidrug-resistant R. equi in fection in Taiwan and documents the relapsing or reactivating nature o f this infection.