Objective: Molecular epidemiologic surveillance of Acinetobacter baumannii by polymerase chain reaction-randomly amplified polymorphic DNA analysis in a university hospital for 3 consecutive study periods.
Results: Twelve different Acinetobacter baumannii genotypes (A-L) were detected. Although only 2 genotypes were detected during the first period and genotype A appeared to be the most common genotype, genotype D was included in these genotypes during the second study period. Genotype A completely disappeared during the third period. Although the presence of genotype C and the genotype D continued during the third period, 9 new genotypes were detected during this period. Genotype A appeared to be the most common genotype in the hospital (detected in 19 different clinics). The distribution of genotypes in clinical samples correlated with patient traffic between them. Some genotypes were found in both clinical and environmental samples. Seventeen different antibiotypes were detected, according to antibiotic susceptibility profiles.
Conclusions: Environmental contamination, airborne transmission, patient transfer, and cross-contamination play important roles in epidemics caused by A. baumannii in our hospital. The distribution of genotypes can change over time, so antibiotyping is not appropriate for the epidemiological analysis of A. baumanii infection.