High-dose intravenous immune globulin and the response to splenectomy in patients with idiopathic thrombocytopenic purpura

A cost-effectiveness study of intravenous immunoglobulin in childhood idiopathic thrombocytopenia purpura patients with life-threatening bleeding

BACKGROUND

Although the international guideline recommends intravenous immunoglobulin (IVIG) as the first-line treatment for childhood idiopathic thrombocytopenia purpura (ITP) with life-threatening bleeding, ITP patients may not be able to access IVIG because of the limitation in health benefit packages especially in developing countries. There remains an important policy question as to whether IVIG used as a first-line treatment is worth the money spent. Thus, the objective of this study was to perform a cost-effectiveness analysis of adding IVIG to the standard treatment of platelet transfusion and corticosteroids, for the treatment of childhood ITP with life-threatening bleeding in the context of Thailand.

METHODS

A cost-effectiveness analysis using a hybrid model consisting of a decision tree and Markov models was conducted with a societal perspective. The effectiveness and utility parameters were determined by systematic reviews, while costs and mortality parameters were determined using a retrospective electronic hospital database analysis. All costs were presented in 2012 US$. The discount rate of 3 % was applied for both costs and outcomes. One-way and probabilistic sensitivity analyses were also performed.

RESULTS

The incremental cost-effectiveness ratio (ICER) was $3,172 per quality-adjusted life-year gained ($/QALY) for the addition of IVIG versus standard treatment alone. The probability of response to corticosteroids was the most influential parameter on ICER. According to the willingness-to-pay of Thailand, of approximately $3,861/QALY, the probability of IVIG being cost effective was 33 %.

CONCLUSIONS

The addition of IVIG to standard treatment in the treatment of childhood ITP with life-threatening bleeding is possibly a cost-effective intervention in Thailand. However, our findings were highly sensitive. Policy makers may consider our findings as part of the information for their decision making.

Severe chronic refractory immune thrombocytopenic purpura during childhood: a survey of physician management

BACKGROUND

Physician attitudes regarding management of children with severe chronic immune thrombocytopenic purpura (ITP) have not been recently characterized.

PROCEDURE

We designed a survey of members of the American Society of Pediatric Hematology-Oncology (ASPHO) that described a 5-year-old female with ITP for 1 year who was unresponsive to steroids, IVIG, and anti-D immune globulin and having frequent epistaxis causing interference with her daily activities. A 13-item questionnaire evaluated physician decision-making in this setting.

RESULTS

Two hundred and ninety-seven surveys (35% response rate) were returned, and 295 were evaluable. Thirty-three percent of respondents stated that they would recommend splenectomy for such a child. Of those who would not recommend splenectomy, 67% reported that they would instead treat with rituximab. If initial drug therapy failed, 47% would proceed with splenectomy. Those who reported treating with rituximab initially were more likely to recommend splenectomy following failure than those who preferred other drug therapy (P < 0.0001).

CONCLUSIONS

Physician management of patients with chronic ITP is diverse. With the advent of new treatments such as rituximab and thrombopoetic agents it is critically important to compare their cost, adverse effects and efficacy with splenectomy in order to optimally guide treatment practices.

Splenectomy in children with idiopathic thrombocytopenic purpura: A prospective study of 134 children from the Intercontinental Childhood ITP Study Group

BACKGROUND

Splenectomy is an effective procedure for children and adults with severe or refractory idiopathic thrombocytopenic purpura (ITP). Data regarding pediatric patients are limited.

PROCEDURE

Sixty-eight Intercontinental Childhood ITP Study Group (ICIS) investigators from 57 institutions in 25 countries participated in a splenectomy registry. Data from 153 patients were submitted, of whom 134 had a splenectomy and were analyzed.

RESULTS

The median age at splenectomy was 11.8 (2.7-20.7) years. The median postsplenectomy follow-up was 2.0 (0.1-4.5) years. Pre-splenectomy vaccination was not administered in 21 children (15.7%). Open and laparoscopic splenectomy procedures were performed in 67 and 65 evaluable children, respectively. Surgical technique was not reported in two children. Overall immediate platelet response to splenectomy was achieved in 113 patients (86.3%). Eighty percent of responders maintained their status of response during the following 4 years. Older age, longer duration of ITP, and male gender correlated with a complete response. Post-splenectomy sepsis was reported in seven patients without lethal outcome, although sepsis might be differently defined at participating institutions.

CONCLUSIONS

Splenectomy is effective in children with ITP. Management varies greatly in different institutions. These Registry data may serve as a basis for future clinical trials to assess the indication and timing of splenectomy.

Splenectomy in children with chronic ITP: long-term efficacy and relation between its outcome and responses to previous treatments

This retrospective study was conducted to determine whether the response to splenectomy is related to the response to previous treatments. We examined the records of 90 children splenectomized for chronic ITP. Platelet counts were constantly>50x10(9)/L in 68 patients (75%). An improvement in the quality of life was observed in 79 (85%). The success of splenectomy was strongly correlated with a good response to previous treatment. A negative response to any of the prior treatments had no predictive value. This finding is relevant when elective splenectomy is considered as a treatment option.

Splenectomy for adult chronic idiopathic thrombocytopenic purpura: experience from a single center in China

OBJECTIVES

The aim of this study was to explore the results of Chinese chronic idiopathic thrombocytopenic purpura (ITP) patients who underwent splenectomy (SE).

SUBJECTS AND METHODS

Data of 149 chronic ITP patients were retrospectively analyzed. Relapse-free survival was estimated by Kaplan-Meier analysis. Differences between responders and non-responders were evaluated using the chi-square.

RESULTS

The immediate response rate was 82.6% and the sustained response rate was 63.1%. Twenty-nine patients (19.5%) relapsed during follow-up. The 5-year actuarial relapse-free survival was about 75%. The overall morbidity was 26.1% and mortality was 2.7%. Patients with higher postsplenectomy peak platelet count, shorter time from diagnosis to SE and previous response to IVIG therapy were more likely to have sustained response to SE.

CONCLUSION

SE is potentially a useful therapy to provide long-term control of disease in adults with chronic ITP and is associated with low morbidity and mortality. Postsplenectomy peak platelet count, time from diagnosis to SE and previous response to intravenous immune globulin therapy appear predictive for response to SE.

Splenectomy for adult patients with idiopathic thrombocytopenic purpura: a systematic review to assess long-term platelet count responses, prediction of response, and surgical complications

Splenectomy has been a standard treatment for adult patients with idiopathic thrombocytopenic purpura (ITP) for more than 50 years. However, the durability of responses, the ability to predict who will respond, and the frequency of surgical complications with splenectomy all remain uncertain. To better interpret current knowledge we systematically identified and reviewed all 135 case series, 1966 to 2004, that described 15 or more consecutive patients who had splenectomy for ITP and that had data for 1 of these 3 outcomes. Complete response was defined as a normal platelet count following splenectomy and for the duration of follow-up with no additional treatment. Forty-seven case series reported complete response in 1731 (66%) of 2623 adult patients with follow-up for 1 to 153 months; complete response rates did not correlate with duration of follow-up (r = -0.103, P = .49). None of 12 preoperative characteristics that have been reported consistently predicted response to splenectomy. Mortality was 1.0% (48 of 4955 patients) with laparotomy and 0.2% (3 of 1301 patients) with laparoscopy. Complication rates were 12.9% (318 of 2465) with laparotomy and 9.6% (88 of 921 patients) with laparoscopic splenectomy. Although the risk of surgery is an important consideration, splenectomy provides a high frequency of durable responses for adult patients with ITP. (Blood. 2004; 104:2623-2634)

Management of immune thrombocytopenic purpura in adults

Primary immune thrombocytopenic purpura (ITP), also referred to as idiopathic thrombocytopenic purpura, is an organ-specific autoimmune disorder in which antibody-coated or immune complex-coated platelets are destroyed prematurely by the reticuloendothelial system, resulting in peripheral blood thrombocytopenia. The disease is heterogeneous with regard to its severity and clinical course and is unpredictable in its response to therapy. Although the basic underlying pathophysiology of ITP has been known for more than 50 years, current treatment guidelines are based on expert opinion rather than on evidence because of a lack of high-quality clinical trials and research. The only patients for whom treatment is clearly required are those with severe bleeding and/or extremely low platelet counts (< 10 x 10(9)/L). Treatment of patients with ITP refractory to corticosteroids and splenectomy requires careful evaluation of disease severity, patient characteristics related to risk of bleeding, and adverse effects associated with treatment. Clinical trials with numerous new agents are under way, which we hope will add more effective and targeted strategies to our therapeutic armamentarium. We describe a logical and structured approach to the clinical management of ITP in adults, based on a literature review and our personal experience.

Management of adult immune thrombocytopenia

Immune thrombocytopenia (ITP) is a heterogeneous disease with regard to pathogenesis, severity, spontaneous course and response to treatment. Except in patients with severe bleeding tendency and very low platelet counts (< 10 x 10(9)/L), there are no clear rules on the indications for treatment. The standard initial therapy is corticosteroids, but the optimal dose and duration of therapy is unknown and in practice, some patients may be overtreated by aiming for complete remission (CR). In patients who have no sustained response after steroids, the most effective single therapy is splenectomy. Laparascopic splenectomy has a very low mortality and moderate morbidity. Preoperative prediction of success is difficult. About 50% of patients are in CR or partial remission after 5 years, but there are few data on the long-term outcome. Patients who fail steroids and splenectomy are difficult to treat. The choice may be palliative, with low doses of steroids or aggressive therapy with the intention of sustained remission. In selected patients, high-dose immunoglobulin or anti-D may be useful to temporarily raise the platelet count. Other drugs tried in ITP had either no or very limited clinically meaningful efficacy.

Response to high-dose intravenous immune globulin as a valuable factor predicting the effect of splenectomy in chronic idiopathic thrombocytopenic purpura patients

This study was conducted to verify whether the response to high-dose intravenous immune globulin (IVIG) was related to the effect of splenectomy in chronic idiopathic thrombocytopenic purpura (ITP) patients. A total of 79 patients over 16 years of age were enrolled in this study. The response to the treatment was classified on the basis of the platelet count as no response (NR, <50 x 10(9)/l), incomplete response (IR, (50-150) x 10(9)/l), and complete response (CR, >150 x 10(9)/l). The response was evaluated after the infusion of high-dose IVIG, within 2 weeks after splenectomy (immediate response), and during a follow-up period of more than 6 months after splenectomy (sustained response), respectively. 58 patients (73.4%) showed responses (CR or IR) to high-dose IVIG. After splenectomy, immediate responses were observed in 73 patients (92%). The response to high-dose IVIG had no relationship with the immediate response to splenectomy (P = 0.333). A follow-up evaluation was possible with 58 patients; 6 patients with NR in immediate responses did not show any response during the follow-up period, and 17 patients relapsed within 6 months after immediate responses, so 35 patients (60.3%) had sustained responses. Responders to IVIG had significantly higher sustained response rates to splenectomy than non-responders (62% vs. 38%, P = 0.001). These results indicate that the response to high-dose IVIG could be a valuable factor predicting the sustained response to splenectomy in chronic ITP patients.

The response to splenectomy in pediatric patients with idiopathic thrombocytopenic purpura who fail high-dose intravenous immune globulin

BACKGROUND

A recent article by Law et al concluded that patients with idiopathic thrombocytopenic purpura (ITP) who have a poor response to intravenous immune globulin (IgG) are unlikely to have a good or excellent response to surgical splenectomy.

METHODS

The authors studied retrospectively 23 pediatric patients age 11.7 +/- 1.0 years with ITP who had been treated with IgG before undergoing splenectomy. As in the aforementioned article, the responses to the 2 treatments were classified on the basis of the platelet count as poor (<50,000/mm3), good (50,000 to 150,000/mm3), or excellent (>150,000/mm3). For patients who received multiple IgG treatments, both initial and final treatment responses were analyzed.

RESULTS

Sixteen patients had an excellent or good initial response to IgG. Of these 16 patients, 14 had an excellent or good response to splenectomy. Among the 7 patients who had a poor response to IgG there were 3 who had an excellent or good response to splenectomy (43%), and 4 patients who had a poor response to splenectomy. A good or excellent response to initial treatment with IgG was associated with a significant probability of a good or excellent response to splenectomy (P = .045).

CONCLUSIONS

A good or excellent response to IgG may be predictive of a favorable response to splenectomy. However, a poor response to IgG does not preclude a satisfactory response to splenectomy in pediatric patients with ITP.

The response to high-dose intravenous immunoglobulin or steroids is not predictive of outcome after splenectomy in adults with autoimmune thrombocytopenic purpura

The response to high-dose intravenous immunoglobulin (IVIg) was recently reported to be predictive of outcome after splenectomy in patients with autoimmune thrombocytopenic purpura (AITP). We analysed the records of 75 adults with chronic AITP who received IVIg and subsequently underwent splenectomy. There was no significant difference in the response rate to splenectomy according to whether or not patients had responded to IVIg (81% v 67%, P = 0.36). Age, the time from diagnosis to splenectomy, and the response to steroids were also not significantly associated with outcome after splenectomy. These results indicate that the response to IVIg or steroids is not predictive of the efficacy of splenectomy.