Hostname: page-component-7b7567c8c-tnzcf Total loading time: 0 Render date: 2026-11-15T08:32:22.416Z Has data issue: false hasContentIssue false

Evaluation of Three Molecular Typing Techniques for Nonfermentative Gram-Negative Bacilli

Published online by Cambridge University Press:  02 January 2015

Suzane Silbert*
Affiliation:
Laboratório Especial de Microbiologia Clínica, Disciplina de Doenças Infecciosas e Parasitàrias, Universidade Federal de São Paulo, São Paulo, Brasil
Michael A. Pfaller
Affiliation:
Molecular Epidemiology and Fungus Testing Laboratory, Department of Pathology, University of Iowa College of MedicineIowa City, Iowa
Richard J. Hollis
Affiliation:
Molecular Epidemiology and Fungus Testing Laboratory, Department of Pathology, University of Iowa College of MedicineIowa City, Iowa
Afonso L. Barth
Affiliation:
Unidade de Pesquisa Biomédica, Serviço de Patologia Clínica, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brasil
Hélio S. Sader
Affiliation:
Laboratório Especial de Microbiologia Clínica, Disciplina de Doenças Infecciosas e Parasitàrias, Universidade Federal de São Paulo, São Paulo, Brasil
*
Laboratòrio Especial de Microbiologia Clínica (LEMC)Disciplina de Doenças Infecciosas e Parasitárias, Escola Paulista de Medicina – Universidade Federal de São Paulo, Rua Leandro Dupret, 188, São Paulo, SP – CEP 04025-010, Brasil

Abstract

Objective:

To evaluate three different DNA techniques for typing nonfermentative gram-negative bacilli isolated from Latin American hospitals.

Design:

One hundred twenty-six nonfermentative gram-negative bacilli were typed.

Participants:

Pseudomonas aeruginosa (n = 64) and Acinetobacter baumannii (n = 42) samples were obtained from blood cultures of patients admitted to 10 medical centers in Latin America during 1998 and Stenotrophomonas maltophilia (n = 20) samples were obtained from patients admitted to the Hospital São Paulo between 1999 and 2001.

Methods:

All samples were typed using automated ribotyping, PFGE, and ERIC-PCR. The discriminatory power for each technique was calculated using Hunter's generalized formula.

Results:

All strains could be typed by automated ribotyping and ERIC-PCR, but two strains (1.6%) were not typeable by PFGE. All three techniques showed 100% reproducibility. The time to obtain the results was shorter for automated ribotyping and ERIC-PCR compared with PFGE. Likewise, the costs for ERIC-PCR and PFGE were lower than those for automated ribotyping. The interpretation of results was more complicated and more difficult with ERIC-PCR than with both PFGE and automated ribotyping. All techniques presented excellent discriminatory power for P. aeruginosa (0.98). PFGE presented the highest discriminatory power (0.94) for A. baumannii, and both PFGE and ERIC-PCR showed higher discriminatory power (0.90 for both) than automated ribotyping (0.82) for S. maltophilia.

Conclusions:

PFGE showed the highest discriminatory power for typing these nonfermentative gram-negative bacilli. However, automated ribotyping and ERIC-PCR can provide results in a shorter time period with similar discriminatory power.

Information

Type
Orginal Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2004 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable