Efficient recovery of fluoroquinolone-susceptible and fluoroquinolone-resistant Escherichia coli strains from frozen samples.
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.
Lautenbach
Ebbing
E
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
Santana
Evelyn
E
Lee
Abby
A
Tolomeo
Pam
P
Black
Nicole
N
Babson
Andrew
A
Perencevich
Eli N
EN
Harris
Anthony D
AD
Smith
Catherine A
CA
Maslow
Joel
J
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
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones