title: Molecular epidemiology of penicillin-susceptible, multidrug-resistant serotype 6B pneumococci isolated from children in Greece.
abstract: Since January 1996, and over a 3-year time span, a significant spread of serotype 6B multidrug-resistant (MDR) pneumococci, susceptible to penicillin and resistant to erythromycin, clindamycin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole, was noted in young carriers living in central and southern Greece. Using restriction fragment end labeling and penicillin binding protein (PBP) genotyping, we studied 41 serotype 6B penicillin-susceptible MDR pneumococci isolated during two independent studies in Greece. Forty (98%) of these 41 isolates were strongly related, representing a single lineage (genetic relatedness, > or = 91%). The Greek isolates were closely related (genetic relatedness, approximately 91%) to the penicillin-resistant MDR clone of serotype 6B that spread from Spain to Iceland in the late 1980s. Moreover, the Greek group of isolates was genetically distinct (genetic relatedness, < or = 83%) from other penicillin-susceptible or -resistant serotype 6B strains from various parts of the world. All serotype 6B penicillin-susceptible MDR isolates displayed a penicillin-susceptible PBP 1A-2B-2X genotype. Our findings suggest that the penicillin-susceptible MDR 6B clone that was found in Greece between the years 1996 and 1999 represents the ancestor of the pandemic penicillin-resistant MDR clone 6B.
authors.affiliation: Department of Pediatrics, General University Hospital, University of Patras, School of Medicine, 26 500 Rion, Patras, Greece. syrogian@med.upatras.gr
authors.forename: G A
authors.initials: GA
authors.lastname: Syrogiannopoulos
authors.forename: D
authors.initials: D
authors.lastname: Bogaert
authors.forename: I N
authors.initials: IN
authors.lastname: Grivea
authors.forename: N G
authors.initials: NG
authors.lastname: Beratis
authors.forename: R
authors.initials: R
authors.lastname: De Groot R
authors.forename: P W
authors.initials: PW
authors.lastname: Hermans
mesh_terms: D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000235:genetics; D002648:Child; D018432:Drug Resistance, Multiple; D005838:Genotype; D006115:Greece / Q000453:epidemiology; D006602:Hexosyltransferases; D006801:Humans; D017720:Molecular Epidemiology / Q000379:methods; D002267:Muramoylpentapeptide Carboxypeptidase / Q000235:genetics; D010403:Penicillin Resistance / Q000235:genetics; D046915:Penicillin-Binding Proteins; D010406:Penicillins / Q000627:therapeutic use; D010458:Peptidyl Transferases; D010802:Phylogeny; D011008:Pneumococcal Infections / Q000453:epidemiology*; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D010406:Penicillins; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase