TABLE I.
Patient Characteristics: Comparison of Case and Control Groups
| RBC antibody positive (n = 30) | RBC antibody negative (n = 43) | P-value | |
|---|---|---|---|
| Age (years) | 14.5 ± 3.0 (9.1–19.4) | 11.7 ± 4.7 (3.9–20.1) | 0.003 |
| Female | 12 (40.0) | 20 (46.5) | 0.58 |
| Male | 18 (60.0) | 23 (53.5) | |
| Lifetime number of RBC units | 0.40 | ||
| <25 | 8 (26.7) | 20 (46.5) | |
| 25–49 | 4 (13.3) | 4 (9.3) | |
| 50–99 | 11 (36.7) | 12 (27.9) | |
| ≥100 | 7 (23.3) | 7 (16.3) | |
| Chronic transfusion therapy | 0.69 | ||
| Never | 7 (23.3) | 10 (23.3) | |
| Past | 8 (26.7) | 8 (18.6) | |
| Current | 15 (50.0) | 25 (58.1) | |
| RBC leukoreduction (LR) history | 0.10 | ||
| Exclusively LR | 15 (50.0) | 32 (74.4) | |
| Not exclusively LR | 9 (30.0) | 7 (16.3) | |
| Incomplete LR history | 6 (20.0) | 4 (9.3) | |
| Past splenectomy | 5 (16.6) | 10 (23.3) | 0.49 |
| Days from last RBC transfusion | 234 ± 446 (21–2,265) | 313 ± 551 (12–2,280) | 0.52 |
Age in years and days from last RBC transfusion are expressed as the mean ± standard deviation (range). Within each case or control group, the number of female and male patients, the number of patients to receive <25, 25–49, 50–99, and ≥100 RBC units, the number of patients to have never received chronic transfusion therapy or to have received chronic transfusion therapy currently or in the past, the number of patients to have received exclusively leukoreduced (LR) transfusions or not exclusively LR transfusions, and the number of patients with splenectomy are given with percentage of each case or control group given in parentheses. The P-value is calculated by t-test or chi-square comparison, as appropriate.