title: Efficacy and acceptability of rectal and perineal sampling for identifying gastrointestinal colonization with extended spectrum β-lactamase Enterobacteriaceae.
abstract: OBJECTIVE
  We evaluated 'pre-laboratory' factors associated with the detection of extended spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) colonization including anatomical site, and staff and patient factors.
  
  
  METHODS
  All admissions to a large London hospital over 3 months were approached to provide rectal and perineal swabs, which were cultured for ESBL-E using chromogenic media. ESBL-E detection rates for patient- or staff-collected rectal or perineal swabs were compared using McNemar tests. Binary logistic regression was used to explore factors associated with patients declining to provide a rectal swab. The impact of simplifying the verbal study description to patients to improve the participation rate was evaluated.
  
  
  RESULTS
  Carriage of ESBL-E was significantly higher in rectal swabs than perineal swabs (7.8% of 4006 versus 3.8% of 4006, p <0.001), whether collected by staff or patients; 31.9% of 869 patients did not provide a rectal swab before the change in study description compared with 7.6% of 3690 patients afterwards (p <0.001). In multivariable analysis, factors associated with patients declining to provide a rectal swab were younger age (OR 0.99, 95% CI 0.99-1.00), female gender (OR 1.26, 95% CI 1.04-1.52), transfers from other hospitals (OR 1.77, 95% CI 1.07-2.93) or an unknown admission route (OR 1.61, 95% CI 1.09-2.37), being admitted before the change in study description (OR 0.39, 95% CI 0.31-0.48), and the staff member who consented the patient (p <0.001); ethnicity was not a significant factor.
  
  
  CONCLUSIONS
  Rectal swabs are recommended for the detection of ESBL-E colonization. Staff and patient factors influence whether patients participate in prevalence studies, which may skew their findings.
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK; Imperial College London Health Protection Research Unit (HPRU) in HCAI and AMR, and Imperial College Healthcare NHS Trust, Infection Prevention and Control, London, UK.
authors.forename: E
authors.initials: E
authors.lastname: Dyakova
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: K N
authors.initials: KN
authors.lastname: Bisnauthsing
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Querol-Rubiera
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Patel
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: C
authors.initials: C
authors.lastname: Ahanonu
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: O
authors.initials: O
authors.lastname: Tosas Auguet
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: Edgeworth
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: S D
authors.initials: SD
authors.lastname: Goldenberg
authors.affiliation: Centre for Clinical Infection and Diagnostics Research, Department of Infectious Diseases, King's College London & Guy's and St. Thomas' NHS Foundation Trust, London, UK; Imperial College London Health Protection Research Unit (HPRU) in HCAI and AMR, and Imperial College Healthcare NHS Trust, Infection Prevention and Control, London, UK. Electronic address: j.otter@imperial.ac.uk.
authors.forename: J A
authors.initials: JA
authors.lastname: Otter
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000175:diagnosis* / Q000382:microbiology; D003430:Cross-Sectional Studies; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000175:diagnosis* / Q000382:microbiology; D005260:Female; D006761:Hospitals; D006801:Humans; D008131:London; D008297:Male; D008875:Middle Aged; D010342:Patient Acceptance of Health Care; D010502:Perineum / Q000382:microbiology*; D012007:Rectum / Q000382:microbiology*; D013048:Specimen Handling / Q000379:methods*; D055815:Young Adult; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D001618:beta-Lactamases
keywords: Colonization; Diagnostic sensitivity; Extended spectrum β-lactamase; Patient acceptability; Screening; Staff acceptability; Surveillance cultures