This study was performed to investigate the prevalence and genetic characteristics of transferable bla_CTX-M-15 from hospital- and community-acquired Klebsiella pneumoniae isolates in Scotland. A total of 219 clinical isolates of K. pneumoniae collected in 2006 and 2007 at the Royal Infirmary of Edinburgh, Scotland, were tested for antimicrobial susceptibility by the agar double dilution method. PCR and sequencing were used to detect bla_CTX-M, bla_TEM, bla_SHV and qnr genes. Clonality of the isolates was assessed by PFGE. Sixteen (7.3%) isolates were found to be producers of CTX-M-15 extended-spectrum β-lactamases (ESBLs), of which two isolates (12.5%) were reported to be from patients with community-acquired infections. The ISEcp1 was detected by sequencing 48 nucleotides upstream of bla_CTX-M-15 in all isolates but one. A total of one to two plasmids, ranging in size from ∼40 to 210 kb, were observed per strain. By a PCR-based replicon typing method, plasmids carrying bla_CTX-M-15 were assigned to IncFII or IncN types. Sequencing and PCR analysis revealed the presence of complex class 1 integrons in all isolates but one. Two isolates positive for class 1 integrons were positive for class 2 integrons as well. Five different clones of CTX-M-15-producing isolates were identified by PFGE. This work reports the emergence of hospital- and community-acquired CTX-M-type enzymes in the Edinburgh area of Scotland.

Streptococcus iniae causes high mortalities in aquaculture farms all over the world. This study aimed to isolate, identify pathogenicity and genetic relatedness of S. iniae obtained from cultured Nile tilapia (O. niloticus) at Kafr El-Shiekh Governorate. Fourteen isolates of pure S. iniae cultures were biochemically identified, and confirmed through amplification and sequencing of the 16S rRNA gene. Experimental challenge with six selected isolates resulted in marked clinical signs similar to those recorded in natural infections. The LD50 values were ranged between 3.7×107 to 4.3×108 cfu/fish. All strains were sensitive to oxytetracycline and florfenicol. In repetitive sequence-based PCR (rep-PCR) analysis using the BoxA primer, isolates presented genetic heterogeneity and were divided into six genotypes banding patterns. Understanding the epizootiology and genetic variability between S. iniae isolates, could help for better control and vaccine development.