1431. Prevalence and Genetic Types of ESBL-Producing Strains of Escherichia coli in Pregnant Women in Japan
Session: Poster Abstract Session: Epidemiology of Multiple Drug-Resistant Gram Negative Rods
Saturday, October 20, 2012
Room: SDCC Poster Hall F-H
Background: Increased detection of community-acquired infection with extended-spectrum β-lactamase (ESBL)-producing strains of Escherichia coli is being reported. Infection with CTX-M-producing, especially CTX-M-15 ESBL-producing, strains has reached epidemic proportions worldwide. E. coli is the second common pathogen of neonatal bacterial meningitis. This study investigated the prevalence and genetic types of ESBL-producing E. coli strains in samples from the maternity section of the University of Tokyo Hospital, Japan.

Methods: During January 2005–December 2011, vaginal-secretion samples obtained during prenatal check-up for group B Streptococcus or from women suspected to have gynecological infections were analyzed for ESBL-producing E. coli strains. ESBLs were characterized by PCR and sequencing. Strain relatedness was examined by pulsed-field gel electrophoresis.

Results: ESBL-producing E. coli strains were isolated in 16 cases, i.e., from vaginal secretions of 15 mothers and gastric fluid from a newborn of a carrier mother. The proportion of samples with ESBL-producing E. coli from the total vaginal-secretion samples greatly increased during the study period (2007, 0%; 2009, 0.08%; 2011, 0.36%). The proportion of ESBL-producing strains from non-ESBL strains isolated from vaginal secretions also increased (2007, 0%; 2009, 1.33%; 2011, 5.95%). Twelve of the 16 samples with ESBL-producing E. coli had been obtained in the outpatient ward or on the admission day. The strains recovered from 1 mother and her baby were identical. All other strains were epidemiologically unrelated. Different CTX-M enzymes were characterized: CTX-M-14 (n = 9); CTX-M-3 (n = 4); double positive for CTX-M-14, 3 (n = 2); and CTX-M-8 (n = 1).

Conclusion: Thus, the annual prevalence of community-acquired infection with ESBL-producing E. coli is increasing in maternity section. In addition, the genetic types of the ESBL-producing E. coli isolated in this study were similar to the Japanese epidemic type but differed from the worldwide epidemic type CTX-M-15. The results also provide evidence of mother-to-neonate transmission of such strains. The prevalence of ESBL-producing E. coli in the perinatal unit greatly influences therapy choices.

Yoko Nukui, MD, PhD1, Shuji Hatakeyama, MD, PhD2, Kunihiko Fukuchi, MD, PhD3, Shu Okugawa, MD, PhD1 and Kyoji Moriya, MD, PhD1, (1)Department of Infection Control and Prevention, University of Tokyo Hospital, Tokyo, Japan, (2)Department of Infectious Diseases, University of Tokyo Hospital, Tokyo, Japan, (3)Department of Clinico-diagnositic Pathology, Showa University School of Medicine, Tokyo, Japan


Y. Nukui, None

S. Hatakeyama, None

K. Fukuchi, None

S. Okugawa, None

K. Moriya, None

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