Genotyping of Pseudomonas aeruginosa in cystic fibrosis suggests need for segregation.
BACKGROUND
Emerging resistance of Pseudomonas aeruginosa within cystic fibrosis (CF) populations is attributed to antibiotic pressure and spread of transmissible strains. We describe increasing resistance of P. aeruginosa isolates, resulting in the identification of two multiresistant strains and their impact on morbidity.


METHODS
Susceptibility reports of all P. aeruginosa isolates since 1998 in our unit were reviewed. Isolates were submitted for genomic finger-printing by pulsed-field gel electrophoresis. Clinical measures and the consumption of treatment resources were compared between those harbouring resistant organisms and those with sensitive strains.


RESULTS
Analysis of 407 reports from 43 patients revealed isolation of multiresistant (MR) organisms increased during 1999. Those harbouring MR strains consumed more resources than non-MR. Strain typing showed a new 'Sheffield' strain in seven patients (100% MR), and the 'Liverpool' strain in 10 patients (40% MR). Individuals in these groups consumed significantly more resources than 23 patients with unique, susceptible strains (4% MR).


CONCLUSIONS
Increasing resistance in isolates of P. aeruginosa may herald the arrival of a transmissible strain in CF Units which though sometimes sensitive, may become multiply resistant and require more intensive treatment. We now segregate those with transmissible strains from each other and from those with unique strains.
Edenborough
F P
FP
Adult Cystic Fibrosis Unit, Northern General Hospital, Herries Road, Sheffield, S5 7AU, UK. fedenborough@yahoo.com
Stone
H R
HR
Kelly
S J
SJ
Zadik
P
P
Doherty
C J
CJ
Govan
J R W
JR
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003550:Cystic Fibrosis / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D016172:DNA Fingerprinting; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D005838:Genotype; D006301:Health Services Needs and Demand; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D010597:Pharmacogenetics; D011287:Prejudice; D011336:Probability; D011552:Pseudomonas Infections / Q000175:diagnosis / Q000188:drug therapy; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics*; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
D000900:Anti-Bacterial Agents