Molecular detection and identification of -lactamases would be
essential for a reliable epidemiological investigation of antimicrobial
resistance. Until now, ESBL genes have been studied in different
parts of the world but not in the Marrakech region. This is the first
systematic study that reports the diversity of ESBL genes among
ESBL-producing urinary E. coli isolated in this region. Three types
of ESBL were detected in our study: CTX-M, SHV and TEM.
Clearly, CTX-M ESBLs are the most prevalent among single ESBL
types produced by E. coli in our study, accounting for 70% of the
ESBLs compared with SHV (12%) and TEM (0%). This is a dramatic
turnaround from the situation in the 1990s when TEM and
SHV ESBLs were dominant and CTX-M types were rarely recognized.
The distribution of ESBL-producing genes in our series,
with a large predominance of CTX-M, is similar to those reported
in several countries including Argentina, the UK, Spain, France and
India [5,22–25], among others countries where CTX-M-producing
Enterobacteriaceae have been described to be endemic.