Genotyping Approach for Potential Common Source of Enterocytozoon bieneusi Infection in Hematology Unit

Microsporidiosis is a fungal infection that generally causes digestive disorders, especially in immunocompromised hosts. Over a 4-day period in January 2018, 3 patients with hematologic malignancies who were admitted to the hematology unit of a hospital in France received diagnoses of Enterocytozoon bieneusi microsporidiosis. This unusually high incidence was investigated by sequence analysis at the internal transcribed spacer rDNA locus and then by 3 microsatellites and 1 minisatellite for multilocus genotyping. The 3 isolates had many sequence similarities and belonged to a new genotype closely related to genotype C. In addition, multilocus genotyping showed high genetic distances with all the other strains collected from epidemiologically unrelated persons; none of these strains belonged to the new genotype. These data confirm the epidemiologic link among the 3 patients and support a common source of infection.