title: Efficient recovery of fluoroquinolone-susceptible and fluoroquinolone-resistant Escherichia coli strains from frozen samples.
abstract: We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only in low numbers in the initial sample. These findings emphasize the utility of frozen surveillance samples.
authors.affiliation: Division of Infectious Diseases of the Department of Medicine, the Department of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6021, USA. ebbing@mail.med.upenn.edu
authors.forename: Ebbing
authors.initials: E
authors.lastname: Lautenbach
authors.forename: Evelyn
authors.initials: E
authors.lastname: Santana
authors.forename: Abby
authors.initials: A
authors.lastname: Lee
authors.forename: Pam
authors.initials: P
authors.lastname: Tolomeo
authors.forename: Nicole
authors.initials: N
authors.lastname: Black
authors.forename: Andrew
authors.initials: A
authors.lastname: Babson
authors.forename: Eli N
authors.initials: EN
authors.lastname: Perencevich
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Harris
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Smith
authors.forename: Joel
authors.initials: J
authors.lastname: Maslow
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015925:Cryopreservation; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology*; D005615:Freezing; D006801:Humans; D008297:Male; D008875:Middle Aged; D010414:Pennsylvania; D012007:Rectum / Q000382:microbiology; D012680:Sensitivity and Specificity
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones