Table 2. Performance of BKV viral load for the prediction of BKV-associated nephropathy, using a commercial and an in-house QPCR test.

	Sensitivity % (95% CI)	Specificity % (95% CI)	PPV % (CI 95%)	NPV % (CI 95%)
Plasma viral load (copies/ml)
≥3.8 log (commercial PCR kit)	88 (47-98)	96 (90-99)	64 (31-89)	99 (94-100)
≥4.1 log (commercial PCR kit)	88 (47-98)	98 (93-100)	77 (40-97)	99 (94-100)
≥6.1 log (in-house method)	87 (81-93)	100 (94-100)	73 (39-94)	100 (91-100)

Legend: CI, confidence interval; NPV, negative predictive value; PPV, positive predictive value; qPCR, quantitative real-time polymerase chain reaction.