Increasing net immunosuppression after BK polyoma virus infection

Area of Science:

• Nephrology
• Transplant Immunology
• Virology

Background:

• BK viremia (BKV) and BK nephropathy management involves reducing immunosuppression.
• This reduction increases risks of acute rejection and donor-specific antibodies (DSA).
• The safety and efficacy of re-escalating immunosuppression for resolving BKV remain unevaluated.

Purpose of the Study:

• To evaluate the impact of increasing immunosuppression on outcomes in kidney transplant recipients with resolving BKV.
• To assess the safety and efficacy of re-escalating immunosuppression in this patient population.

Main Methods:

• Retrospective review of 88 kidney transplant recipients with BKV (plasma PCR ≥ 1000 copies/ml).
• Patients were grouped based on whether net immunosuppression was increased after initial reduction.
• Outcomes tracked included biopsy-proven acute rejection (BPAR), de novo DSA, and graft survival.

Main Results:

• 50% of patients (44/88) had immunosuppression increased; groups were similar in viremia and sensitization.
• Increasing immunosuppression was linked to significantly less BPAR (P=.001) and a trend toward less de novo DSA (P=.06).
• Death-censored graft survival was not significantly different; recurrent BKV occurred in 22.7% of the increased immunosuppression group without graft loss.

Conclusions:

• Increasing immunosuppression in kidney transplant patients with resolving BKV may offer benefits in preventing rejection and DSA.
• Further prospective trials are necessary to confirm these findings and optimize immunosuppression strategies.
• This approach warrants consideration in managing BKV post-transplant.