Abstract
BK virus nephropathy (BKVN) and allograft rejection are two distinct disease entities which occur at opposite ends of the immune spectrum. However, they coexist in renal transplant recipients. Predisposing factors for this coexistence remain elusive. We identified nine biopsy-proven BKVN patients with coexisting acute rejection, and 21 patients with BKVN alone. We retrospectively analyzed the dosage and blood concentrations of immunosuppressants during the 3-month period prior to the renal biopsy between the two patient groups. Compared to the BKVN alone group, renal function was noticeably worse in the coexistence group (p = 0.030). Regarding the dose and average drug level of immunosuppressants, there was no difference between the two groups. Interestingly, the coefficient of variance of tacrolimus trough blood level was noticeably higher during the 3-month period prior to the renal biopsy in the coexistence group (p = 0.010). Our novel findings suggest that a higher variability of tacrolimus trough level may be associated with the coexistence of BKVN and acute rejection. Since the prognosis is poor and the treatment is challenging in patients with coexisting BKVN and acute rejection, transplant clinicians should strive to avoid fluctuations in immunosuppressant drug levels in patients with either one of these two disease entities.
Highlights
Both BK virus nephropathy (BKVN) and acute rejection present with a decline in renal function[8, 9], very different management strategies are needed, and a renal biopsy may be required for a definite diagnosis
There was no difference in the type of acute rejection
This study identified that the coexistence of BKVN and acute rejection was noticeably associated with a fluctuating tacrolimus trough blood level during the 3-month period prior to the renal biopsy but not with the dose or the average drug level of any immunosuppressant
Summary
Both BKVN and acute rejection present with a decline in renal function[8, 9], very different management strategies are needed, and a renal biopsy may be required for a definite diagnosis. BKVN and acute rejection may occur at the same time, with a reported incidence ranging from 1%~24%10–12. A recent study reported an unfavorable clinical outcome when BKVN and acute rejection coexist[15]. The pathogenesis and predisposing factors for the coexistence of BKVN and acute rejection remain unknown. It has been reported that fluctuations in the blood levels of tacrolimus are strongly related to poor kidney graft function[21,22,23,24,25]. High drug level variability has been reported to promote donor-specific antibody development and increased graft rejection rates[26,27,28]. We hypothesized that fluctuations in immunosuppressant drug level may be associated with the coexistence of BKVN and acute rejection. Predisposing factors in order to help transplant clinicians prevent the development of this disease and eventually improve allograft outcomes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
