Abstract
Introduction: In January 2000, two patients with severe Immune-Mediated Thrombocytopenia (ITP) at our institution were successfully treated with prolonged infusions of IVIg and platelets. The dose of IVIg was 1 g/kg given by continuous infusion over 24 hours with concurrent platelets (1 pheresis unit every 8 hours). Based on these preliminary results, we evaluated this protocol in a larger series of 40 ITP patients.
Methods: We performed an IRB-approved retrospective review of adult hospitalized patients with ITP treated with this regimen from January 2000 - December 2005. Patients with clinically significant thrombocytopenia and either active bleeding, need for anticoagulation, or requirement for a surgical procedure received the combined treatment. The subjects received IVIg and platelets as described above. Additional treatments, such as steroids, immunosupressives, or rituximab, as well as splenectomy were utilized at the discretion of the hematologist overseeing their care.
Results: The average age of patients treated was 52 years. The majority of patients ranged from 20–80 years old, but 12.5% were older than 80 years. The average pretreatment platelet count was 10,000/μl, with an increase to 55,000/μl after 24 hours, and 69,000/μl after 48 hours. By 72 hours, the average platelet count had begun to decline, although the platelet count remained at an acceptable level (58,200/μl). After 24 hours, 62.7% of patients had a platelet count > 50,000/μl. Bleeding was controlled initially in all patients, and those requiring a procedure experienced no bleeding complications. Over half of the patients (52.5%) required additional treatments for recurrent or refractory ITP, and 32.5% of the patients underwent splenectomy. Six of the 21 patients requiring later retreatment (29%) received IVIg and platelets again in a similar fashion. The average retreatment platelet counts after 24 and 48 hours were 53,000/μl and 49,000/μl respectively, with clinical improvement in bleeding in all patients. No side effects of the combined treatment were noted. The response rates for the 3 IVIg products used were similar.
Discussion: For ITP, IVIg and platelets are considered to be first line treatment for patients with very low platelet counts, active bleeding, or those requiring urgent procedures. There is limited literature on the optimal dose and schedule for administration of IVIg and platelets. Our approach for administration of IVIg and platelets concurrently was associated with minimal side effects, resolution of bleeding, ability to safely undergo procedures, and rapid restoration of adequate platelet counts. Additionally, elderly patients had equivalent benefit with no increased side effects, indicating that this regimen is appropriate and safe for patients of all age groups.
