Table I. Comparison of the Clinical and Laboratory Characteristics of the North American Chronic ITP Registry by Whether Patients Were Treated With Rituximab.
| NACIR patients: no rituximab |
NACIR patients: treated with rituximab |
P-value | |
|---|---|---|---|
| Total number of subjects (n) | 485 | 80 | |
| Median age at diagnosis (years) | 8.6 (IQR 4.2, 12.8) | 7.5 (IQR 4.9, 12.0) | 0.59 |
| Ages 0–2 | 10.9% | 18.8% | |
| Ages >2–10 | 46.0% | 45.0% | |
| Ages >10 | 43.1% | 36.3% | |
| Gender (male) | 46.4% | 43.8% | 0.72 |
| Race | 0.05 | ||
| Caucasian | 70.5% | 61.3% | |
| Black | 4.7% | 12.5% | |
| Asian | 6.0% | 7.5% | |
| Other/unknown | 18.8% | 18.7% | |
| Hispanic | 20.3% | 17.5% | 0.73 |
| Median platelet count at acute ITP diagnosis (kcells/µl) | 13 (IQR 6, 33) | 10 (IQR 5, 20) | 0.03 |
| Median platelet count at chronic ITP diagnosis (kcells/µl) | 40 (IQR 20, 71) | 14 (IQR 8, 35) | <0.01 |
| Primary ITP | 89.5% | 76.3% | <0.01 |
| Secondary ITP | 10.5% | 23.7% | |
| Evans syndrome | 6.8% | 17.5% | |
| Antecedent viral illness | 28.1% | 22.1% | 0.33 |
| Positive ANA (>1:40) | 28.4% | 29.6% | 0.87 |
| Direct anti-globulin positivea | 20.3% | 33.3% | 0.05 |
| Median duration of symptoms before Diagnosis of ITP (months) | 0.47 (IQR 0.07, 2) | 0.23 (IQR 0.06, 1) | 0.38 |
| Worst documented bleedingb | <0.01 | ||
| Grade 0 | 28.4% | 18.8% | |
| Grade 1 | 40.1% | 35.0% | |
| Grade 2 | 22.8% | 23.8% | |
| Grade 3 | 8.6% | 21.3% | |
| Grade 4 | 0.2% | 1.3% |
IQR, interquartile range; SD, standard deviation.
a
Including transiently positive results with a normal hemoglobin as well as post-anti-D globulintreatment positive results;
b
By modified Buchanan and Adix Bleeding Score [19]. No patients had fatal bleeds.