In this pilot study, 30 (14 male, 16 female; median age: 8 years, range: 2-18) chronic non-splenectomized
idiopathic thrombocytopenic purpura (
ITP) patients with Rh+
blood group and their 49 attacks were evaluated after intravenous (i.v.)
anti-D (WinRho SDF, Cangene Corporation, Winnipeg, MB, Canada) treatment at a dose of 50 microg/kg x 3 days (n = 21 cases; 35 attacks) or a single dose of 75 microg/kg (n = 9 cases; 14 attacks) to define the
hemostatic dose of
anti-D. Five of 30 patients (22/49 attacks) were resistant to
steroid,
intravenous immunoglobulin (
IVIG) and
vincristine treatment.
Hemoglobin (Hb), white blood cells (WBC), platelets (plt) and reticulocytes (ret) were evaluated before and
after treatment during the follow-up in sequences on the 1st, 7th, 14th and 21st days after
anti-D treatment if the patients had no symptom. All patients, even the resistant ones, experienced an increase in plt count to provide protection from
bleeding (> or = 20 x 10(9)/L in patients with symptoms, > or = 10 x 10(9)/L in patients without symptoms). The plt responses of one resistant and five non-resistant patients treated with a single 75 microg/kg dose of i.v.
anti-D in 8 attacks were monitored at the 2nd, 4th, 8th, 24th and 48th hours of the treatment. A protective plt level was attained within 2 hours in 6 attacks of five non-resistant cases and in 24 hours in the remaining 2 attacks of one resistant case. This pilot study suggests that
anti-D treatment in
ITP patients is effective and can increase plt to a level adequate enough to protect from
hemorrhage within 2 hours, when given in a 75 microg/kg dose. A few adverse events (i.e.
chills,
hemolysis and
hemoglobinuria) resolved without intervention.