title: BK virus-associated hemorrhagic cystitis presenting as mural nodules in the urinary bladder after hematopoietic stem cell transplantation.
abstract: We report an unusual sonographic presentation of late-onset hemorrhagic cystitis caused by BK virus infection in an 8-year-old who had undergone hematopoietic stem cell transplantation for treatment of relapsed acute lymphoblastic leukemia. Sonography showed the presence of multiple bladder nodules in a background of diffuse bladder wall thickening. The dominant bladder nodule showed increase in size on serial sonograms and was vascularized on Doppler interrogation. Biopsy confirmed BK virus-associated cystitis. Recognition of this sonographic appearance in the appropriate clinical setting might obviate the need for biopsy in these children.
authors.affiliation: Division of Hematology and Oncology, Department of Paediatrics, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Tal
authors.initials: T
authors.lastname: Schechter
authors.forename: Mira
authors.initials: M
authors.lastname: Liebman
authors.forename: Adam
authors.initials: A
authors.lastname: Gassas
authors.forename: Bo-Yee
authors.initials: BY
authors.lastname: Ngan
authors.forename: Oscar M
authors.initials: OM
authors.lastname: Navarro
mesh_terms: D001739:BK Virus; D002648:Child; D003556:Cystitis / Q000150:complications* / Q000821:virology; D006470:Hemorrhage / Q000150:complications* / Q000821:virology; D006801:Humans; D008297:Male; D027601:Polyomavirus Infections / Q000150:complications*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000150:complications / Q000628:therapy; D012008:Recurrence; D033581:Stem Cell Transplantation / Q000009:adverse effects*; D014412:Tumor Virus Infections / Q000150:complications*; D014463:Ultrasonography; D001743:Urinary Bladder / Q000000981:diagnostic imaging* / Q000473:pathology