title: Clonal dissemination of macrolide-resistant and penicillin-susceptible serotype 3 and penicillin-resistant Taiwan 19F-14 and 23F-15 Streptococcus pneumoniae isolates in Japan: a pilot surveillance study.
abstract: Large-scale surveillance studies using molecular techniques such as pulsed-field gel electrophoresis (PFGE) have revealed that the spread of antibiotic-resistant pneumococci is due to clonal spread. However, in Japan, surveillance studies using such molecular techniques have never been done. Therefore, we conducted a pilot surveillance study to elucidate the present situation in Japan. Among the 145 isolates examined, the most prevalent serotype was type 19F (20%), for which most isolates were not susceptible to penicillin (86.2%) but were positive for the mef(A)/mef(E) gene (89.7%). The secondmost prevalent was serotype 3 (16.6%), for which most isolates were susceptible to penicillin (87.5%) and positive for the erm(B) gene (91.7%). PFGE analysis showed that both serotypes consisted mainly of clonally identical or related isolates and, in particular, 38% of the type 19F isolates were indistinguishable from or closely related to the Taiwan 19F-14 clone. In addition, some of the Japanese type 23F isolates with the erm(B) gene were indistinguishable from or related to the Taiwan 23F-15 clone as analyzed by PFGE. Based on the results of our pilot study performed in a single institution, it is likely that international antibiotic-resistant clones have already spread in Japan; therefore, a nationwide surveillance study should be urgently conducted.
authors.affiliation: Second Department of Internal Medicine, Nara Medical University, 840 Shijo Cho, Kashihara City, Nara 634-8522, Japan. kassan@naramed-u.ac.jp
authors.forename: Kei
authors.initials: K
authors.lastname: Kasahara
authors.forename: Koichi
authors.initials: K
authors.lastname: Maeda
authors.forename: Keiichi
authors.initials: K
authors.lastname: Mikasa
authors.forename: Kenji
authors.initials: K
authors.lastname: Uno
authors.forename: Ken
authors.initials: K
authors.lastname: Takahashi
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Konishi
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Yoshimoto
authors.forename: Koichi
authors.initials: K
authors.lastname: Murakawa
authors.forename: Eiji
authors.initials: E
authors.lastname: Kita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kimura
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004917:Erythromycin / Q000494:pharmacology; D006801:Humans; D007564:Japan; D018942:Macrolides / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology; D010865:Pilot Projects; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D016133:Polymerase Chain Reaction; D011159:Population Surveillance; D015995:Prevalence; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D013624:Taiwan
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D018942:Macrolides; D010406:Penicillins; D004917:Erythromycin