The epidemiological aspects of a suspected outbreak of nosocomial invasive aspergillosis was studied. Sixteen Aspergillus fumigatus strains were isolated from bronchial washings or sputa of 10 patients during a nine month period. Furthermore, two environmental samples, isolated in a microbiological screening of the hospital were also available for analysis. Random amplified polymorphic DNA (RAPD) analysis was carry out by using ten different single oligonucleotides with arbitrary sequences and the molecular profiles were further studied by a software package. Two different primers clearly pointed out substantial genetic variation among the isolates and demonstrate that strains isolated from all patients infected with the same fimgal species and the environmental samples were genotypically distinct. In each of two patients, the same types were detected in sequential sampling whereas in two others the genotype change ftom one sample to another demonstrating the utility of this technique for distinguishing between A. fumigatus isolates. RAPD genotyping proved that the outbreak of invasive aspergillosis consisted of a series of events, non-related, and probably not coming from the same origin within the hospital. This type of analysis is an easy, quick and highly discriminatory technique that may help in planning epidemiological studies of aspergillosis.
Full conference title:
38th Interscience Conference on Antimicrobial Agents and Chemotherapy
- ICAAC 38th