Donor and Recipient BKV-Specific IgG Antibody and Posttransplantation BKV Infection: A Prospective Single-Center Study

Background The study evaluated the relationship of pretransplantation BK virus (BKV)–specific donor and recipient serostatus to posttransplantation BKV infection. Methods Two hundred forty adult de novo kidney-only recipients and 15 pediatric recipients were prospectively enrolled and followed for a minimum of 18 months. Pretransplantation BKV serostatus was available for 192 adult and 11 pediatric donor–recipient pairs. Based on BKV-specific IgG enzyme immunoassay ≥8 units, subjects were divided into four groups: D+R+, D+R-, D-R+, and D-R-. BKV DNA surveillance was performed at 1, 3, 6, 12, and 24 months. The outcomes studied were development of any BKV infection, viremia, and significant viremia (≥10,000 copies/mL plasma). Results Of the 192 adult subjects (D+R- [n=41], D+R+ [n=42], D-R+ [n=41], and D-R- [n=68]), 89 of 192 developed any BKV infection and 62 of 89 developed BK insignificant viremia (n=33) and significant viremia (n=29). Any BKV infection developed in 25 of 41, 22 of 42, 17 of 41, and 25 of 68 in the D+R-, D+R+, D-R+, and D-R- groups, respectively. Any viremia (20 of 41) and significant viremia (10 of 41) seen in the D+R- group was significantly higher than other groups (P=0.014). In 11 pediatric recipients, infection was seen only in the D+R- group. Overall, infection was highest in the D+R- group and lowest in the D-R- group. Conclusions BKV serostatus can be used to risk stratify patients for posttransplantation infection.