Comparison of rapid automated laser fluorescence analysis of DNA fingerprints with four other computer-assisted approaches for studying relationships between Acinetobacter baumannii isolates.

The relationships between isolates suggested by a novel DNA typing method (RAPD-ALFA) that combines randomly amplified polymorphic DNA with automated on-line laser fluorescence analysis of DNA fragments were compared with those suggested by four other computer-assisted typing strategies (biotyping, antibiogram typing, pulsed-field gel analysis of chromosomal fingerprints and arbitrarily-primed DNA amplification with three different primers) for 25 isolates of Acinetobacter baumannii obtained from 12 different hospitals in four countries over a period of 12 years. The results obtained by cluster analysis with two different software packages confirmed that the relationships suggested by RAPD-ALFA were robust and essentially similar to those suggested by the other more laborious computer-assisted typing methods. The technique of RAPD-ALFA appears to offer the possibility of routine on-line molecular identification and typing of isolates from particular hospital wards or units (e.g., intensive care units), and could, therefore, play a key role in the early recognition and prevention of outbreaks of infection.