Pulsed high-dose dexamethasone in refractory chronic idiopathic thrombocytopenic purpura: a report on 10 cases

Summary. We treated 10 patients who had chronic refractory idiopathic thrombocytopenic purpura (ITP) with high-dose dexamethasone (DXM, 40mg/d for 4 sequential days every month). The interval from diagnosis ranged from 49 to 300 months, and patients had previously received a median of 5.5 treatments (including splenectomy in nine cases). Median platelet count was 14 × 10⁹/1 (range 6-26 × 10⁹/1) at the onset of DXM and eight patients had bleeding symptoms. Eight patients received at least three cycles of DXM.
Five patients had a response (i.e. platelet count at least doubled and increased by >20 × 10⁹/1), including one almost complete remission and four minor responses (MR).
Of the MR, one was probably due to concurrent IVIg administration, and all four MR were transient, in spite of further cycles of DXM. In three patients DXM was a failure after three or four cycles. In two patients DXM had to be stopped after one course because of major side-effects (systemic hypertension with stroke and insulin-dependent diabetes, respectively).
In our experience, high-dose DXM had a relatively limited effect in chronic refractory ITP and was associated with severe side-effects in some cases.     

Slow infusions of vinblastine in the treatment of adult idiopathic thrombocytopenic purpura: A report on 43 cases

Summary Forty-three adult patients with idiopathic thrombocytopenic purpura (ITP) were treated by slow intravenous infusions of vinblastine. Nineteen had ITP of recent onset (i.e. of less than 6 months duration) and had contraindication to steroids (3 patients), refractoriness to steroids (6 patients) or to steroids and high dose intravenous immunoglobulins (IVIg, 10 patients). Of the 19 patients, 10 achieved complete response (CR), 2 achieved partial response (PR), 2 had minor response (MR) and the remaining 5 patients had no response (NR). Six of the complete responders remained in CR after 12 to 48 months, whereas all other responders relapsed within 3 months, in spite of maintenance therapy. Twenty-four patients had chronic ITP (i.e. of 6 months duration or more) and had showed no or only transient response to steroids and/or splenectomy, and in many of them, to other therapeutic approaches. Four achieved CR, 4 PR, 6 MR and 10 NR. All but 2 responses were shorter than 3 months, in spite of maintenance therapy. Most responses to slow infusions of vinblastine began after the first infusion. Main side effects included leukopenia in 9 patients (but with absolute neutropenia in only one) and peripheral neuropathy in 2 patients. Interval from diagnosis was the only prognostic factor of response to treatment. We conclude that slow infusions of vinblastine may be a useful approach in ITP of recent onset, when contraindication or refractoriness to steroids and/or IVIg exists. In our experience, this treatment has limited benefit in chronic ITP. In addition, it remains to be demonstrated that slow infusions of vinca alkaloids have any superiority over intravenous bolus injections of the same drugs.     

Emergency splenectomy in adult idiopathic thrombocytopenic purpura. A report of seven cases

Seven adult patients with idiopathic thrombocytopenic purpura underwent emergency splenectomy. Six were female and one was a male, aged 16 to 61 years. All of them had a life-threatening episode. Six patients had progressive intracranial bleeding and one had postsurgical intra-abdominal bleeding. All patients were saved by surgery, except one for whom operation was delayed. There was no postoperative bleeding or surgical complication. Immediate splenectomy should be the treatment of choice in any patient with idiopathic thrombocytopenic purpura complicated by life-threatening hemorrhage.     

Intravenous gammaglobulin treatment of chronic idiopathic thrombocytopenic purpura

High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen.     

Rituximab treatment for chronic refractory idiopathic thrombocytopenic purpura

Idiopathic thrombocytopenic purpura (ITP) is characterized by mucocutaneous bleeding and a low platelet count caused by increased autoantibodies against self-antigens and T-cell mediated cytotoxicity. About 10-30% patients with ITP will become refractory ITP. Most of them will become refractory to corticosteroids and splenectomy, as well as other available agents such as intravenous immunoglobulins, danazol, or chemotherapy. B cells not only are the passive producers of immunoglobulins, but also play an important immunoregulatory role in pathophysiology of ITP. Rituximab, a chimeric anti-CD20 monoclonal antibody that specifically targets the CD20 molecule on the B-cell surface, is useful in the treatment of ITP through B cells depletion. Rituximab has multiple mechanisms of inducing cytotoxicity in vivo, including antibody-dependent cell-mediated cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), direct apoptosis signaling, and possible vaccine effects. In most clinical reports, rituximab was given as an intravenous infusion at a dose of 375 mg/m(2) weekly for four doses. A total complete response (CR) of 33.2% and a total response of 52.9% were reported. Most results found that no clinical or laboratory parameters could predict treatment outcome. Though the infusion-related side effects of rituximab were common in ITP, it was well tolerated with rare severe side effects. In general, rituximab appears to be a promising immunotherapeutic agent for the treatment of refractory ITP. More controlled clinical trials are necessary to evaluate both the efficacy and long-term safety of the drug.     

Reevaluation of the prognostic factors for splenectomy in chronic idiopathic thrombocytopenic purpura (ITP): a report on 181 cases

From 1973 to 1986 we splenectomized 181 patients with chronic ITP after platelet kinetic studies with 51Cr or 111In. Mean age at diagnosis was 34 (range 4-79 yr). Follow-up of at least 1 yr after splenectomy was available in every patient. 141 patients (78%) achieved remission (platelets greater than 100 x 10(9)/l by 3 months after splenectomy), of whom 9 subsequently relapsed. Among the 40 non-responders at 3 months, 3 achieved a later remission spontaneously. Factors associated with response to splenectomy included a high post-operative platelet count (p = 0.0001), younger age at the time of surgery (p = 0.0077) and predominantly splenic sequestration of platelets (p = 0.0002), the two latter factors being partially correlated. In a multivariate analysis, however, only post-operative platelet count and age retained an independent prognostic significance, whereas the sequestration site of platelets had only borderline value. These results are discussed in the context of indications of platelet kinetic studies in chronic ITP, before splenectomy is considered.     

Dapsone for chronic autoimmune thrombocytopenic purpura: a report of 66 cases

Sixty-six adults with chronic autoimmune thrombocytopenic purpura AITP and platelet count <50 ×10⁹ l were treated with dapsone (75–100 mg orally). A response was observed in 33 patients. The median duration of treatment required to obtain a response was 21 d (range 8–90). The median maximal platelet count on treatment was 130 × 10⁹ l (range 71–355). Dapsone was continued in 20/33 responders for a median of 12.5 months (range 1–48) and the response persisted in 19. Treatment was intentionally withdrawn in the other 13 responders and thrombocytopenia immediately recurred in 12. Reversible side-effects required cessation of treatment in seven patients. These results demonstrate that dapsone is an effective, inexpensive, and well-tolerated treatment for chronic AITP.     

DNA甲基化在成人特发性血小板减少性紫癜发病机制中的作用

目的 从DNA甲基化角度探讨成人特发性血小板减少性紫癜(ITP)的发病机制.方法 应用SYBR Green实时定量PCR方法测定48例成人ITP患者与36例正常对照者外周血单个核细胞DNA甲基转移酶1(DNMTl)、DNA甲基转移酶3A(DNMT3A)和DNA甲基转移酶3B(DNMT3B)的mRNA的相对表达水平.采用反相高效液相技术(HPLC)检测ITP患者与正常对照血浆中S-腺苷蛋氨酸(SAM)和S-腺苷同型半胱氨酸(SAH)含量.运用流式细胞术检测ITP患者与正常对照外周血CD_4~+和CD_8~+T细胞表面淋巴细胞功能相关抗原-1(LFA-1)亚单位C11a的表达水平.结果 成人ITP患者外周血单个核细胞DNMT3A和DNMT3B mRNA表达水平较对照组减低(P<0.01);DNMTl mRNA表达水平与对照组相比有降低趋势,但差异无统计学意义(P>0.05).成人ITP患者血浆SAH与对照组相比增高,差异有统计学意义(P<0.05);而血浆SAM和SAM/SAH比率与正常对照组相比差异无统计学意义(P值均>0.05).成人ITP患者外周血CD_8~+CD_(11a)~+细胞比例显著高于对照组(P<0.01),而CD_4~+CD_(11a)~+细胞比例和CD_4~+CD_(11a)~+/CD_4~+CD_(11a)~+比率较对照组显著降低(P值均<0.01),差异有统计学意义.结论 成人ITP患者外周血存在淋巴细胞低甲基化状态以及T细胞亚型上存在异常的CD_(11a)/LFA-1表达.DNA甲基化可能在ITP的发病中起一定的作用,但确切的作用机制还有待于进一步深入研究.     

Platelet antigens in chronic idiopathic thrombocytopenic purpura

IgG produced by splenic cells from five patients with chronic immune thrombocytopenic purpura (ITP) and from four control subjects was radiolabelled and incubated with target platelets. Eluates from these platelets were incubated with solubilized proteins from the same platelets immobilized on nitrocellulose paper. After washing, putative antigens were localized by autoradiography. Positive results were obtained in three of the five ITP patients; in two patients three radiolabelled bands of high molecular weight were noted (greater than 200 000) and in the third patient two different bands (molecular weight 140 000 and 105 000) were seen. Control studies were negative. These studies show that patients with chronic ITP produce antibody reactive with antigens associated with human platelet proteins and that the antigenic pattern differs between patients.     

Laparoscopic splenectomy in chronic idiopathic thrombocytopenic purpura

Splenectomy remains the definitive treatment for idiopathic thrombocytopenic purpura (ITP). Issues related to timing of splenectomy, perioperative management of platelet count, deep vein thrombosis prophylaxis, and preoperative vaccination are not standardized. Predicting the outcome of splenectomy is desirable but, again, consistent evidence for a particular approach is lacking. Laparoscopic splenectomy, first introduced in 1991, has removed some of the barriers to acceptance of splenectomy and may well change its place in the various treatment algorithms. This article reviews current knowledge with respect to laparoscopic splenectomy and provides an analysis of current evidence regarding issues of safety, efficacy, and cost effectiveness. Surgical technique is briefly reviewed. The information is drawn from a comprehensive analysis of the literature, as well as my own large experience with laparoscopic splenectomy, the majority of which has been focused on laparoscopic splenectomy for ITP.     

Rituximab for the treatment of refractory idiopathic thrombocytopenic purpura (ITP) and thrombotic thrombocytopenic purpura (TTP): report of three cases

Three patients (one with idiopathic thrombocytopenic purpura [ITP] and two with thrombotic thrombocytopenic purpura [TTP]) were treated with rituximab (anti-CD20 chimeric antibody) at a dose of 325 mg/m2 administered weekly after they failed standard therapies. The patient with ITP who did not respond to steroids and anti-D antibody administration achieved augmentation of her platelet counts up to 180 x 10(3)/microL after four doses of rituximab. Six months later, when her counts started to decrease, she received maintenance therapy with an additional course of 4 standard doses of antibody that resulted in consolidation of her platelet counts around 100 x 10(3)/microL. One patient with TTP and concurrent idiopathic nephropathy who was previously treated with plasmapheresis, steroids, and vincristine improved only after 4 weekly administrations of the antibody. Moreover, his nephrotic-range proteinuria resolved after he received rituximab. The other patient with chronic TTP who still relapsed after splenectomy received 5 doses of rituximab with concomitant plasmapheresis. His thrombocytopenia improved slowly, and his platelet count stabilized at 300 x 10(3)/microL. All three patients showed evidence of response to anti-CD20 antibody with improvement in clinical outcome as well as augmentation of platelet counts to normal levels. We conclude that rituximab is a useful immunomodulating adjunct in the treatment of refractory ITP and TTP.     

Immunosuppressive therapy of chronic idiopathic thrombocytopenic purpura

The results of 17 courses of immunosuppressive therapy in 12 adult patients with chronic idiopathic thrombocytopenic purpura were compared to those reported in 94 patients in the literature. About 50 per cent of the reported patients with chronic idiopathic thrombocytopenic purpura treated with immunosuppressive drugs have had a successful response. In most of these, however, the idiopathic thrombocytopenic purpura was of short duration which suggests that many of the responses were spontaneous. The probability of response to immunosuppressive agents is much greater in the splenectomized patient than in the nonsplenectomized patient.Azathioprine and cyclophosphamide are the drugs of choice for the immunosuppressive therapy of chronic idiopathic thrombocytopenic purpura. The immunosuppressive effects of cyclophosphamide probably are better, but the potential complications of this drug in patients with chronic idiopathic thrombocytopenic purpura are more serious. Nonsteroidal immunosuppressive therapy should be used as the primary form of treatment only in patients with serious disease who fail to respond to corticosteroid therapy and who are poor risks for splenectomy. One or more courses of nonsteroidal immunosuppressive therapy may be indicated in patients with chronic refractory idiopathic thrombocytopenic purpura with life-threatening disease. It is expected that from 15 to 35 per cent of adults and probably more children with chronic refractory idiopathic thrombocytopenic purpura will have a successful response.The use of nonsteroidal immunosuppressive drugs in patients with chronic idiopathic thrombocytopenic purpura remains experimental and involves uncertain risks to the patient.     

Clinicopathologic and prognostic features of chronic idiopathic thrombocytopenic purpura in adult Chinese patients: an analysis of 220 cases

To determine the clinicopathologic and prognostic features of chronic idiopathic thrombocytopenic purpura (ITP) in adult Chinese patients, we conducted a retrospective analysis of 220 patients seen at a single center over a 40-year period. The female-to-male ratio was 4:1, with a mean age of 42.1 +/- 1.3 years, a mean platelet count of 33.7 +/- 2.3x10(9)/l, and a mean follow-up of 116 +/- 7 months. Initial steroid treatment was required in 142 patients, 67 of whom (47.2%) achieved complete remission (CR). At 470 months, 46% patients remained in CR. Splenectomy was performed in 37 patients: in 23 patients due to primary steroid refractoriness and in 7 patients due to disease relapse following initial CR with steroids. In seven patients, data on response to steroids prior to splenectomy were not available. Splenectomy for steroid nonresponders resulted in an inferior CR rate (13 of 23, 56%) as compared with that for relapses after steroid treatment (7 of 7, 100%) (P<0.05). Compared with patients with negative antinuclear antibody (ANA), those who were ANA positive had similar responses to steroids, but significantly shorter remission after splenectomy (P<0.01). In conclusion, Chinese patients with ITP could maintain long-term remission after steroid therapy and splenectomy. In addition, primary steroid refractoriness and positive ANA were bad prognostic factors of the subsequent response to splenectomy.