Table 2.
Characteristics of HHV-6B Reactivation and Outcomes of Treated vs Observed Patients
| Outcomes | Observation (n = 37) | Treated With Antivirals (n = 21) | P Value |
|---|---|---|---|
| High-level DNAemia ≥10 000 copies/mL (peak), No. (%) | 15 (40.5) | 18 (85.7) | <.001 |
| Median onset of DNAemia (IQR), d from HCT | 26 (24.0–32.5) | 23 (18.5–26.5) | .022 |
| Median peak viral load (IQR), copies/mL | 6840 (1670–35 250) | 44 900 (20 200–210 000) | <.001 |
| Median peak viral load (IQR), log10 | 3.84 (3.22–4.54) | 4.65 (4.29–5.32) | <.001 |
| Median time to peak viral load (IQR), d | 27 (24.0–32.5) | 25 (20.0–32.0) | .303 |
| LP performed, No. (%) | 10 (27) | 16 (76.2) | <.001 |
| HHV-6 in CSF, No. (% of LP) | 2 (20) | 4 (25) | 1.00 |
| CNS symptoms, No. (%) | 4 (10.8) | 7 (33.3) | .077 |
| Median onset of CNS symptoms (IQR), d from HCT | 20 (13.75–44.25) | 26 (20.00–33.00) | .788 |
| Median time to clearance of HHV-6 DNA (IQR), d | 12 (7.5–21.0) | 14 (7.0–15.0) | .782 |
| Second reactivation episode, No. (%) | 0 (0) | 4 (19) | .014 |
| Grade II–IV acute GVHD, No. (%) | 13 (35.1) | 12 (57.1) | .104 |
| Grade III/IV acute GVHD, No. (%) | 5 (13.6) | 7 (33.3) | .097 |
| Median time to neutrophil engraftment (IQR), d from HCT | 17 (15.0–20.5) | 20 (16.0–30.5) | .054 |
| Median time to platelet engraftment (IQR), d from HCT | 27.5 (22.5–35.0) | 34.0 (26.0–48.0) | .133 |
| Day 100 NRM, No. (%) | 4 (10.8) | 8 (38.1) | .020 |
Abbreviations: CNS, central nervous system; GVHD, graft-vs-host disease; HCT, hematopoietic cell transplant; HHV-6B, human herpesvirus 6B; IQR, interquartile range; LP, lumbar puncture; NRM, nonrelapse mortality.