Rapid detection and identification of JC virus and BK virus in human urine by using immunofluorescence microscopy.

An indirect immunofluorescence method was developed and used to detect urinary excretion of abnormal transitional cells infected with JC virus (JCV) or BK virus (BKV). This method was compared with urinary cytology, electron microscopy, viral culture, and viral serology in groups of immunosuppressed renal transplant recipients and normal controls. The indirect immunofluorescence method detected and identified JCV excretion in four persons, BKV excretion in one person, and both JCV and BKV excretion in eight others. Viral antigen was identified only in the nuclei of cytologically abnormal cells. Of these 13 persons, 8 also had polyoma virions detected in the urine by electron microscopy. With repeated study of sequential urine samples, 30% of transplant recipients and 6% of normal controls were positive by one or more microscopy methods. Serological results confirmed a high incidence of both JCV and BKV multiplication in the immunosuppressed patients. However, serology did not correlate directly with urinary virological findings. Urinary cytology and the indirect immunofluorescence method were rapid and sensitive methods for detecting and identifying urinary excretion of JCV and BKV.