Co-infection of Polyomavirus-BK and Cytomegalovirus in Renal Transplant Recipients

Abstract

Polyomavirus-BK (BK) is a significant cause of allograft dysfunction in renal transplant recipients. Cytomegalovirus (CMV) and BK infection are thought to be possible risk factors for one another, but no supporting data are yet available. The authors monitored BK and CMV infection by quantitative polymerase chain reaction (PCR) in 69 renal transplant recipients with serum creatinine elevation to determine the prevalence of co-infection. In addition, 150 adult renal transplant recipients were also retrospectively analyzed for both infections. Of 69 recipients, 12 were plasma BK-PCR-positive. Eight of the 12 showed high BK levels (>10 copies) and BK nephropathy. Six of the 12 were also CMV-PCR-positive compared with only 3 of 57 plasma BK-negative patients (50% vs. 5.3%, P=0.001). Comparatively, the incidence of Epstein-Barr virus infection was similar in both groups (1 of 12 [8.3%] vs. 2 of 57 [3.5%], P =not significant). In addition, retrospective analysis of CMV-PCR-positivity in 150 adult renal transplant recipients showed similar results (5 of 6 in BK-PCR-positive [83%] vs. 8 of 144 in BK-PCR-negative [5.6%], P=0.00001). More plasma BK-PCR-positive patients had concomitant CMV infection than CMV-PCR-positive patients with BK infection (5 of 6 [83%] vs. 4 of 13 [31%], P=0.05). In conclusion, high plasma BK-positivity (>10) is significantly associated with BK nephropathy. Plasma BK-positivity is highly associated with co-infection of CMV, suggesting possible risk factors for one another. Therefore, detection of either infection strongly suggests the need to monitor for the other. This strategy may lead to the prevention of virus-induced complications by preemptive antiviral therapy in renal allografts.