Multilocus enzyme electrophoresis analysis of Aspergillus fumigatus strains isolated from the first clinical sample from patients with invasive aspergillosis. EBGA Network. European Research Group on Biotype and Genotype of Aspergillus

The genotypes of 50 isolates of Aspergillus fumigatus from 11 patients with invasive aspergillosis, obtained from three hospitals in different geographical areas, were determined by multilocus enzyme electrophoresis (MLEE). The study analysed the genetic polymorphism of multiple isolates from the first sample. Seven of the 14 enzymic loci studied were polymorphic, giving rise to eight different electrophoretic types. For nine of 11 patients studied, no polymorphism was observed in isolates within the first clinical sample. Analysis of genetic distance between electrophoretic types demonstrated a genetic heterogeneity within each geographical site. Moreover, some genotypes were preferentially found in a given area and this revealed a population structure within these geographical sites. Therefore, the epidemiology of A. fumigatus should be considered separately for each of these areas. The multiple discriminatory markers of MLEE seem to provide a powerful tool for increasing the understanding of the biology of this fungus.