A longitudinal study of lung transplant recipients infected with Aspergillus: Genetic polymorphism of A fumigatus

Background: Aspergillus infection is a well-known complication of lung tran splantation and remains associated with high mortality rates. Molecular typ ing methods are required to elucidate the complex epidemiology of Aspergill us disease in lung transplant recipients. Methods: Eight lung transplant recipients from one hospital were followed f or A fumigatus colonization or infection. Forty-four sequential isolates fr om these patients were selected and typed by three molecular methods (rando m amplified polymorphic DNA, sequence-specific DNA primer and multi-locus e nzyme electrophoresis). Results: Sixteen different types were identified of which 14 were specific to 1 patient. A factorial correspondence analysis showed that variability b etween sequential isolates from a single patient was as high as between iso lates from the other patients. Lung transplant recipients presented many di fferent genotypes, reflecting the environmental diversity of A fumigatus. N evertheless, throughout their follow-up, 2 of the 8 lung transplant recipie nts harbored a common genotype that was not replaced by others. Conclusions: These results confirm the important genetic polymorphism of th e A fumigatus population. The observed genotypes were not related to the ty pe of Aspergillus disease or anti-fungal treatment used nor to the outcome of the patient. These data confirm that all A fumigatus molecular types pre sent the same pathogenic risk.