Quantitative detection of BK virus in kidney transplant recipients: a prospective validation study

• Autor(a) principal: Pinto,Gabriel Godinho
• Data de Publicação: 2018
• Outros Autores: Poloni,José Antonio Tesser, Paskulin,Diego D'Avila, Spuldaro,Fabio, Paris,Fernanda de, Barth,Afonso Luís, Manfro,Roberto Ceratti, Keitel,Elizete, Pasqualotto,Alessandro C.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Jornal Brasileiro de Nefrologia
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0101-28002018000100059
• topic: Kidney Transplantation; Viremia; Polymerase Chain Reaction; Polyomavirus

Abstract Introduction: BK virus (BKV) infection in renal transplant patients may cause kidney allograft dysfunction and graft loss. Accurate determination of BKV viral load is critical to prevent BKV-associated nephropathy (BKVAN) but the cut-off that best predicts BKVAN remains controversial. Objective: To evaluate the performance of a commercial and an in-house qPCR test for quantitative detection of BK virus in kidney transplant recipients. Methods: This was a prospective study with kidney transplant recipients from two large university hospitals in Brazil. Patients were screened for BKV infection every 3 months in the first year post-transplant with a commercial and an in-house real time polymerase chain reaction (qPCR) test. BKVAN was confirmed based on histopathology. The area under the curve for plasma qPCR was determined from receiver operating characteristic analysis. Results: A total of 200 patients were enrolled. Fifty-eight percent were male, 19.5% had diabetes mellitus, and 82% had the kidney transplanted from a deceased donor. BKV viremia was detected in 32.5% and BKVAN was diagnosed in 8 patients (4%). BKVAN was associated with viremia of 4.1 log copies/mL, using a commercial kit. The cut-off for the in-house assay was 6.1 log copies/mL. The linearity between the commercial kit and the in-house assay was R2=0.83. Conclusion: Our study shows that marked variability occurs in BKV viral load when different qPCR methodologies are used. The in-house qPCR assay proved clinically useful, a cheaper option in comparison to commercial qPCR kits. There is an urgent need to make BKV standards available to the international community.