Method | Sensitivity* (%) | Specificity* (%) | PPV* | NPV* | Advantage | Disadvantage |
Plasma quantitative PCR¶ (preferred) | 100 | 88Δ | Moderate | High | - High PPV for BKPyVAN if VL ≥10,000/mL plasma
- Ability to monitor response to therapy (ie, reduction in immunosuppression)
| - Relatively expensive
- Nonstandardized significant variability among assays
- Rare reports of biopsy-confirmed BKPyVAN without concomitant viremia/DNAemia
|
Urine quantitative PCR | 100 | 78 | Moderate | High | - Precedes BKPyV viremia by 6 to 12 weeks
- Earlier identification of patients at risk for subsequent BKPyVAN
| - Limited utility for monitoring response to therapy (ie, immunosuppression reduction)
- May remain persistently positive
|
Urine decoy cells | 100 | 71 | Low | High | | - Decoy cells identification needs experience
- Does not distinguish among polyomaviruses (ie, JCPyV versus BKPyV)
|
Urine Haufen | 100 | 99 | High | High | - High PPV
- Might be useful in settings where allograft biopsy is not feasible
| - Requires electron microscopy
- Not widely available
|