The First Phylogenetically Confirmed Hemorrhagic Cystitis Outbreak Among Pediatric Hematopoietic Stem Cell Transplant Recipients

In phylogenetic analysis, three clusters including 11, 5, and 3 patients having identical sequences were formed. To our knowledge, this is the biggest BKV-HC nosocomial transmission seen among HSCT patients. Nosocomial BKV transmission affecting HSCT patients was proven with phylogenetic and statistical analysis. Furthermore, this study presented a novel finding, describing two HSCT patients affected by nosocomial transmission, evidenced by the presence of BKV-DNA in their urine samples, who had not developed HC. This observation marks the first documented instance of such cases within the context of nosocomial transmission of BKV.