PMC

Minimum-spanning trees showing carriage of extended-spectrum β-lactamases (ESBL) in Escherichia coli isolates from urine samples (A) and samples from patients with bacteremia (B). Each circle represents 1 sequence type (ST), and the size of the circle reflects the number of isolates belonging to this particular ST within the bacteria group. Lines between the circles represent how different their allelic profiles are; a line labeled 1 means the linked STs differ in >1 of the 7 alleles, which is named a single locus variant (SLV). A cluster of STs linked by SLVs is a clonal complex. Nineteen (30.16%) of 63 STs found among the urine isolates were ESBL positive, in comparison to 30 (51.72%) of 58 for the bacteremia isolates.