Occurrence of BK virus and BK virus specific antibodies in the urine of patients receiving chemotherapy for malignancy

Urine specimens from 23 children and 9 adults who were undergoing treatment for malignancy as well as urines from 40 normal individuals were concentrated and examined for evidence of papovavirus infection. Papovavirus particles were detected in 6 of 64 urines examined by electron microscopy. Three of the particle positive urines induced BK virus specific immunofluorescence after inoculation of WI38 cells, and three isolations of BK virus were made by inoculation of urines from virus excreting patients into Vero cells. BK virus specific hemagglutination inhibiting and immunofluorescence neutralizing antibodies were found in a majority of urines from adult patients, in about a fifth of pediatric patients, and less often in normal urines. Urines of virus excreting patients generally had antibodies. In indirect fluorescent antibody tests, BK virus specific antibodies of the immunoglobulin G class were found in five urine specimens from patients; immunoglobulin A antibodies were not detected in any urine. These data suggest that activation of BK virus is related to immunosuppression and not to transplantation itself and that the occurrence of virus specific antibodies in urine may be indicative of virus multiplication in the urinary tract.