Dissemination of high-level penicillin-, extended-spectrum cephalosporin-,and erythromycin-resistant Streptococcus pneumoniae clones in Taiwan

Sixty-seven clinical isolates of Streptococcus pneumoniae (40 of serotype 2 3F, 19 of serotype 19F, and 8 of serotype 6B) with decreased susceptibiliti es to penicillin and erythromycin were characterized by antimicrobial susce ptibility patterns; DNA restriction endonuclease cleavage profiles of the p enicillin-binding protein genes pbp1a, pbp2b, and pbp2x; random amplified p olymorphic DNA (RAPD) patterns generated by arbitrarily primed PCR; and chr omosomal macrorestriction profiles based on pulsed-field gel electrophoresi s. A total of 22 clones (identical or closely related pulsotypes and identi cal RAPD patterns) were identified; 14 clones of 23F, 6 of 19F, and 2 of 6B . Three 23F clones (26 isolates) and one 19F clone (9 isolates) expressed h igh-level resistance to penicillin, cefotaxime, and erythromycin (MICs grea ter than or equal to 256 mu g/ml). These data strongly suggest that multipl e high-level penicillin-, extended-spectrum cephalosporin-, and macrolide-r esistant clones of S. pneumoniae have been disseminated in Taiwan.