title: Molecular epidemiology of Aspergillus fumigatus: an in-depth genotypic analysis of isolates involved in an outbreak of invasive aspergillosis.
abstract: We recently reported an outbreak of invasive aspergillosis in the major heart surgery unit of Hospital Gregorio Marañón, Madrid, Spain (T. Peláez, P. Muñoz, J. Guinea, M. Valerio, M. Giannella, C. H. W. Klaassen, and E. Bouza, Clin. Infect. Dis., in press). Aspergillus fumigatus was isolated from clinical samples from 10 patients admitted to the unit during the outbreak period (surgical wound invasive aspergillosis, n = 2; probable pulmonary invasive aspergillosis, n = 4; colonization, n = 4). In the study described here, we have studied the genotypic diversity of the A. fumigatus isolates found in the air and clinical samples. We used short tandem repeats of A. fumigatus (STRAf) typing to analyze the genotypes found in the 168 available A. fumigatus isolates collected from the clinical samples (n = 109) from the patients and from the environmental samples taken from the air of the unit (n = 59). The genotypic variability of A. fumigatus was higher in environmental than in clinical samples. Intrasample variability was also higher in environmental than in clinical samples: 2 or more different genotypes were found in 26% and 89% of clinical and environmental samples, respectively. We found matches between environmental and clinical isolates in 3 of the 10 patients: 1 patient with postsurgical invasive aspergillosis and 2 patients with probable pulmonary invasive aspergillosis. A total of 7 genotypes from 3 different patients and the air grouped together in 2 clusters. Clonally related genotypes and microvariants were detected in both clinical and environmental samples. STRAf typing proved to be a valuable tool for identifying the source of invasive aspergillosis outbreaks and for studying the genotypic diversity of clinical and environmental A. fumigatus isolates.
authors.affiliation: Clinical Microbiology and Infectious Diseases Department, Hospital General Universitario Gregorio Marañón, Universidad Complutense de Madrid, Madrid, Spain. jguineaortega@yahoo.es
authors.forename: Jesús
authors.initials: J
authors.lastname: Guinea
authors.forename: Darío
authors.initials: D
authors.lastname: García de Viedma
authors.forename: Teresa
authors.initials: T
authors.lastname: Peláez
authors.forename: Pilar
authors.initials: P
authors.lastname: Escribano
authors.forename: Patricia
authors.initials: P
authors.lastname: Muñoz
authors.forename: Jacques F
authors.initials: JF
authors.lastname: Meis
authors.forename: Corné H W
authors.initials: CH
authors.lastname: Klaassen
authors.forename: Emilio
authors.initials: E
authors.lastname: Bouza
mesh_terms: D001232:Aspergillus fumigatus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D004271:DNA, Fungal / Q000235:genetics; D004196:Disease Outbreaks; D004783:Environmental Microbiology; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D055744:Invasive Pulmonary Aspergillosis / Q000453:epidemiology* / Q000382:microbiology*; D017720:Molecular Epidemiology; D058889:Molecular Typing; D016533:Mycological Typing Techniques; D013030:Spain
chemical_list: D004271:DNA, Fungal