Molecular epidemiologic features and antimicrobial susceptibility profiles of various ribotypes of Pseudomonas aeruginosa isolated from humans and ruminants.
OBJECTIVE
To assess automated ribotyping for characterization of Pseudomonas aeruginosa isolates and to identify their type prevalence and geographic distribution.


METHODS
39 human and 56 ruminant P aeruginosa isolates.


METHODS
Isolates were identified by use of bacteriologic techniques and automated Pvull-based ribotyping. Susceptibility to antimicrobials was tested in vitro. Data were analyzed for index of discrimination; prevalence ratio; geographic distribution of ribotypes found only in humans, only in cows, or only in goats (single-host ribotypes); and geographic distribution of ribotypes found in humans and ruminants (multihost ribotypes).


RESULTS
All isolates were typeable (45 ribotypes, 35 single-host ribotypes). Ribotyping index of discrimination was 0.976. More isolates (45.3%) than expected yielded multihost ribotypes (22% of all ribotypes). Although 8.6% of single-host ribotypes were found in 4 or more isolates, 60% of multihost ribotypes were found in 4 or more isolates. Ninety percent of multihost ribotypes were isolated from different geographic areas, whereas 3.0% of single-host ribotypes were isolated from different geographic areas. All ruminant isolates were susceptible to gentamicin and polymyxin B. In contrast, antibiogram profiles differed for human isolates from different geographic areas. Susceptibility to antimicrobials differentiated 6 isolates not distinguished by ribotyping.


CONCLUSIONS
Automated ribotyping with Pvull discriminated more isolates than in vitro antimicrobial susceptibility. In combination, both tests provided more information than either test alone. Given the greater prevalence and geographic distribution of multihost ribotypes, immunocompromised humans and lactating ruminants may have a greater risk for disease if exposed to multihost P aeruginosa ribotypes, compared with single-host ribotypes.
Rivas
A L
AL
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
Bodis
M
M
Bruce
J L
JL
Anderson
K L
KL
Klein
R F
RF
González
R N
RN
Quimby
F W
FW
Batt
C A
CA
Lein
D H
DH
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000382:microbiology*; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000145:classification / Q000235:genetics; D015252:Deoxyribonucleases, Type II Site-Specific / Q000737:chemistry; D005260:Female; D015511:Goat Diseases / Q000453:epidemiology / Q000382:microbiology*; D006041:Goats; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D008892:Milk / Q000382:microbiology; D009515:New Jersey / Q000453:epidemiology; D009518:New York / Q000453:epidemiology; D009657:North Carolina / Q000453:epidemiology; D010802:Phylogeny; D011552:Pseudomonas Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D011550:Pseudomonas aeruginosa / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D021521:Ribotyping / Q000662:veterinary
D004269:DNA, Bacterial; C025630:CAGCTG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific