Detection and characterization of extended-spectrum beta-lactamase-producing Enterobacteriaceae in high-risk patients in an Irish tertiary care hospital. Issue 2 (June 2015)

• Record Type: Journal Article
• Authors: O'Connell, N.; Keating, D.; Kavanagh, J.; Schaffer, K.
• Is Part Of: Journal of hospital infection. Volume 90:Issue 2(2015)
• Page Start: 102
• Page End: 107
• Publication Date: 2015-06
• Subjects: Bacteria -- ESBL -- Resistance -- Hospital -- ICU; Cross infection -- Periodicals; Cross infection -- Prevention -- Periodicals; Nosocomial infections -- Periodicals; Nosocomial infections -- Prevention -- Periodicals; Cross Infection -- Periodicals; Cross Infection -- prevention & control -- Periodicals; Infection Control -- Periodicals; Electronic journals; 614.44
• DOI: 10.1016/j.jhin.2015.01.018
• Languages: English
• ISSNs: 0195-6701

Abstract

Summary: Background: Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) are Gram-negative, multi-drug-resistant organisms that are of major clinical significance among immunocompromised patients in high-risk areas in hospital settings. In Ireland, the number of ESBL-E bloodstream infections is increasing. Aims: To conduct a prevalence study of ESBL-E among immunocompromised patients in high-risk areas [intensive care unit (ICU), liver transplantation and haematology/oncology wards], characterize any ESBL genes detected by polymerase chain reaction (PCR), and perform epidemiological typing using pulsed-field gel electrophoresis (PFGE). Methods: In total, 317 non-duplicate rectal swabs from patients in high-risk wards were screened anonymously for ESBL-E carriage. Positive isolates were characterized using PCR to detect bla CTX-M, bla TEM, bla OXA-1 and bla SHV ESBL-E genes. Clonal relationships of these isolates were investigated using PFGE. Findings: Fifty (15.8%) high-risk patients were found to harbour ESBL-E. Prevalence rates of 21.9% ( N = 28), 14.3% ( N = 15) and 8.3% ( N = 7) of ESBL-E were isolated from patients on the liver transplantation, ICU and haematology/oncology wards, respectively. Seventy percent of ESBL-E isolates carried more than one resistance gene. Of the 25 ESBL-producing Escherichia coli isolates typed by PFGE, two pairs of two isolates demonstrated >80% homology, and four of the five ESBL-producing Enterobacter cloacae isolates typed by PFGE demonstrated >80% homology, suggesting clonal relatedness and potential cross-transmission from individual patients. Conclusion: A significant proportion of the patients screened were found to be colonized with ESBL-E. Typing revealed three incidents of potential cross-infection. Therefore, timely detection of ESBL-E among patients in high-risk wards is critical for treatment and infection control.