A new trilocus sequence-based multiplex-PCR to detect major Acinetobacter baumannii clones

Area of Science:

• Medical Microbiology
• Molecular Biology
• Infectious Diseases

Background:

• Acinetobacter baumannii is a significant nosocomial pathogen.
• Four major clonal complexes (CC) are prevalent in Brazil.
• Existing methods like trilocus sequence-based typing (3LST) multiplex-PCR have limitations in identifying these key CC.

Purpose of the Study:

• To develop an alternative multiplex-PCR scheme for accurate identification of prevalent Acinetobacter baumannii clonal complexes.
• To address the limitations of existing typing methods for Brazilian isolates.

Main Methods:

• Multilocus sequence typing (MLST) was used for isolate characterization.
• Comparative sequence analysis of ompA, csuE, and blaOXA-51-like genes.
• Design and validation of a novel multiplex-PCR assay using a set of eight primers.

Main Results:

• The new multiplex-PCR assay successfully identified five leading Acinetobacter baumannii CC (113/79, 103/15, 109/1, 110/25, and 118/2).
• The assay demonstrated high accuracy in blind testing of study isolates.
• Only 12% of isolates were classified using the existing 3LST multiplex-PCR, highlighting the improved discriminatory power of the new method.

Conclusions:

• The developed multiplex-PCR is a rapid, single-reaction tool for identifying key Acinetobacter baumannii clones.
• This method can significantly aid in preventing the spread of these pathogens in healthcare environments.
• The assay's ability to detect multiple prevalent CC offers a valuable advancement in infection control strategies.