Baseline characteristics
| . | IVIg (n = 100) . | Observation (n = 100) . |
|---|---|---|
| Male | 54 (54.0) | 55 (55.0) |
| Age, y | 3.6 (0.3-16.1) | 4.5 (0.5-16.6) |
| 0-1 y | 3 (3) | 5 (5) |
| 1-10 y | 83 (83) | 71 (71) |
| >10 y | 14 (14) | 24 (24) |
| Duration of symptoms, d | 3 (1-60)* | 3 (0-60)* |
| Platelet count at diagnosis, ×109/L | 6 (0-20) | 5 (0-20) |
| Preceding infection | 56 (56.6) | 51 (52.0) |
| Preceding vaccination | 3 (3.0) | 5 (5.1) |
| Mucosal bleeding, grade 3 | 38 (38.4) | 42 (42.4) |
| Leukocyte count, ×109/L | 8.7 (4.5-17.5) | 8.0 (4.0-18.6) |
| Lymphocyte count, ×109/L | 4.0 (1.3-12.6) | 3.7 (0.9-14.0) |
| FCGR2B† | ||
| 232II | 74 | 64 |
| 232IT | 22 | 17 |
| 232TT | 3 | 0 |
| . | IVIg (n = 100) . | Observation (n = 100) . |
|---|---|---|
| Male | 54 (54.0) | 55 (55.0) |
| Age, y | 3.6 (0.3-16.1) | 4.5 (0.5-16.6) |
| 0-1 y | 3 (3) | 5 (5) |
| 1-10 y | 83 (83) | 71 (71) |
| >10 y | 14 (14) | 24 (24) |
| Duration of symptoms, d | 3 (1-60)* | 3 (0-60)* |
| Platelet count at diagnosis, ×109/L | 6 (0-20) | 5 (0-20) |
| Preceding infection | 56 (56.6) | 51 (52.0) |
| Preceding vaccination | 3 (3.0) | 5 (5.1) |
| Mucosal bleeding, grade 3 | 38 (38.4) | 42 (42.4) |
| Leukocyte count, ×109/L | 8.7 (4.5-17.5) | 8.0 (4.0-18.6) |
| Lymphocyte count, ×109/L | 4.0 (1.3-12.6) | 3.7 (0.9-14.0) |
| FCGR2B† | ||
| 232II | 74 | 64 |
| 232IT | 22 | 17 |
| 232TT | 3 | 0 |
Data are numbers (%) or medians (minimum-maximum) unless otherwise specified. Duration of symptoms denotes the duration of symptoms at the moment of diagnosis of ITP. Preceding infection: an infection within 28 days before diagnosis. Preceding vaccination: a vaccination within 28 days before diagnosis. Because of a small amount of missing data, percentages do not always correspond with the total number of patients.
FCGR, IgG-Fc receptor.
In both groups there was 1 patient with a longer duration of bleeding symptoms, 60 d, before the diagnosis of ITP was made. Because symptoms were mild and not necessarily explained by ITP, combined with the fact that according to current definitions they were still categorized as newly diagnosed ITP, both patients were not excluded from the study.
Blood samples for multiplex ligation probe amplification were available for 99/100 patients in the IVIg group and for 81/100 patients in the observation group.