Prevalence of polyomavirus among United Arab Emirates kidney transplant recipients: results from a single center.

Background: BK viremia and nephropathy are increasing problems in renal transplant recipients. The absence of a safe and effective antiviral therapy made screening-based prevention a recommended strategy. The prevalence of its reactivation among recipients of kidney transplants in the Middle East has not been well established. Our objective was to determine the prevalence of BK virus (BKV) infection for renal transplant recipients at our medical center.

Methods: All renal transplant recipients followed up in our transplantation clinic between 2012 and 2013 (n = 116) were screened. Urine and blood quantitative real-time polymerase chain reaction (PCR) for the BKV were performed in all of the study patients. Renal biopsy was performed only in patients with deteriorating renal function associated with positive PCR. Patients who showed positive BKV PCR were followed up for 6 to 12 months. This included clinical and kidney function assessment along with BKV PCR viral load.

Results: Among the 116 kidney transplant recipients studied, 65 (56%) were male, age 51 ± 15 years, with a transplantation vintage of 131 ± 61 months; 17 (14.7%) were positive for BKV PCR. Three (2.7%) showed viremia; 2 of them had deterioration of kidney function, renal biopsy confirmed the diagnosis of BK nephropathy (NP) in both cases. The 3 cases were managed by reducing the immunosuppressive treatment with stabilization of their kidney function. Cases with stable renal function and positive urine for BKV cleared the virus spontaneously during follow-up after minor reduction of the immunosuppressive treatment or without any intervention. None of our patients lost the graft due to BK NP.

Conclusion: Our study suggests that BKV is not uncommon in our kidney transplant recipients. Routine screening suggested by the KDIGO Guidelines could help minimize its detrimental impact on the transplant outcome.