Table 4.
Effect of medulla on BK virus allograft nephropathy diagnosis in viremia
| Multivariable Risk Factors | Odds Ratio | 95% Confidence Interval |
|---|---|---|
| Prior BK viremia (any) | 2.35 | 1.19 to 4.65 |
| BK viremia, loge copies per milliliter | 1.23 | 1.08 to 1.40 |
| Indication (versus protocol) | 2.03 | 1.06 to 3.89 |
| Maximal core length, mm | 0.99 | 0.94 to 1.03 |
| Medulla present | 2.51 | 1.36 to 4.62 |
A subgroup sensitivity analysis from viremic cases (n=275 biopsies from 150 patients) used multivariable binomial generalized estimating equations against biopsy-proven BK infection (univariable data are detailed in Supplemental Table 8A). Medulla was the only statistically significant parameter of tissue adequacy remaining after control by multivariable regression. Prior BK viremia indicates persistent (chronic) viremia, and BK viremia reflects current viremia circulating viral load at biopsy (loge transformed). Serum creatinine was interchangeable with indication biopsy as a risk factor.