[Genotyping of clinical isolates of Aspergillus flavus and its relationship with environmental isolates of an oncohematological center].

BACKGROUND

During 4 months, and while conducting an environmental sampling of air, 2 cases of aspergillosis by Aspergillus flavus (A. flavus) were diagnosed at an oncohematological center in Buenos Aires, Argentina.

AIMS

The aim of this study was to know the variability and the genetic relationship between the clinical and environmental isolates, obtained in the oncohematological center.

METHODS

Two genotyping techniques of different discriminatory power (RAPD and AFLP) were used. A genetic similarity matrix was calculated using Jaccard method and was the basis for the construction of a dendrogram by UPGMA. The level of genetic variability was assessed by measuring the percentage of polymorphic loci, number of effective allele, expected heterocygozity and association index test (I(A)).

RESULTS

The dendrogram reveals that the A. flavus isolates recovered from the patients were not genetically related to those gotten from the rooms occupied by the patients. The environmental isolates had higher values of genetic diversity than the clinical isolates. The I(A) estimated for all the isolates suggest that recombination events occurred.

CONCLUSIONS

Patients 1 and 2 were not infected with isolates from the nosocomial environment. Clinical and environmental isolates of A. flavus showed high genetic variability among them.