Mycophenolate mofetil therapy for severe immune thrombocytopenia.

Severe immune thrombocytopenia purpura (ITP) presents a clinical challenge. Second-line treatment options are variable without a precise protocol. We present 46 severe ITP patients treated with mycophenolate mofetil (MMF), retrospectively identified from three London teaching hospitals. Data was collected on patient demographics, co-morbidities and previous treatment strategies. Our key interest was whether there was a sustained response in platelet count to MMF. Patients included 27 males and 19 females whose ages ranged from 19 to 93 years old (median 52·5 years). Twenty-nine had primary ITP and 17 had secondary ITP, a third of whom had viral-associated disease. The standard dose of MMF was 1 g/day. Twenty-four patients (52%) responded with 15 (33%) achieving a complete response. No active viral-associated ITP patients demonstrated a response to MMF, although numbers were small (n = 4). We were not able to demonstrate a difference between responders and non-responders based on gender, age, previous therapies or time since diagnosis of ITP. Three of four previously splenectomized patients responded, two achieving complete response. We conclude that MMF is a useful steroid-sparing immunosuppressant to be considered in the second-line or later treatment of ITP.

How I treat thrombocytopenia in pregnancy.

A mild thrombocytopenia is relatively frequent during pregnancy and has generally no consequences for either the mother or the fetus. Although representing no threat in the majority of patients, thrombocytopenia may result from a range of pathologic conditions requiring closer monitoring and possible therapy. Two clinical scenarios are particularly relevant for their prevalence and the issues relating to their management. The first is the presence of isolated thrombocytopenia and the differential diagnosis between primary immune thrombocytopenia and gestational thrombocytopenia. The second is thrombocytopenia associated with preeclampsia and its look-alikes and their distinction from thrombotic thrombocytopenic purpura and the hemolytic uremic syndrome. In this review, we describe a systematic approach to the diagnosis and treatment of these disease entities using a case presentation format. Our discussion includes the antenatal and perinatal management of both the mother and fetus.

Standardization of bleeding assessment in immune thrombocytopenia: report from the International Working Group.

In a previous publication on new terminology, definitions, and outcome criteria for immune thrombocytopenia (ITP), the International Working Group (IWG) on ITP acknowledged that response to treatment should consist of clinically meaningful end points such as bleeding manifestations and that platelet count may not be the ideal parameter for capturing the benefits of therapy. The IWG now proposes a consensus-based ITP-specific bleeding assessment tool (ITP-BAT) with definitions and terminology consistent with those adopted for other bleeding disorders. Bleeding manifestations were grouped into three major domains: skin (S), visible mucosae (M), and organs (O), with gradation of severity (SMOG). Each bleeding manifestation is assessed at the time of examination. Severity is graded from 0 to 3 or 4, with grade 5 for any fatal bleeding. Bleeding reported by the patient without medical documentation is graded 1. Within each domain, the same grade is assigned to bleeding manifestations of similar clinical impact. The "worst bleeding manifestation since the last visit" (observation period) is graded (a suitable database collection form is provided), and the highest grade within each domain is recorded. The SMOG system provides a consistent description of the bleeding phenotype in ITP, and the IWG unanimously supports its adoption and validation in future clinical studies.

Outcomes 5 years after response to rituximab therapy in children and adults with immune thrombocytopenia.

Treatments for immune thrombocytopenic purpura (ITP) providing durable platelet responses without continued dosing are limited. Whereas complete responses (CRs) to B-cell depletion in ITP usually last for 1 year in adults, partial responses (PRs) are less durable. Comparable data do not exist for children and 5-year outcomes are unavailable. Patients with ITP treated with rituximab who achieved CRs and PRs (platelets > 150 × 10(9)/L or 50-150 × 10(9)/L, respectively) were selected to be assessed for duration of their response; 72 adults whose response lasted at least 1 year and 66 children with response of any duration were included. Patients had baseline platelet counts < 30 × 10(9)/L; 95% had ITP of > 6 months in duration. Adults and children each had initial overall response rates of 57% and similar 5-year estimates of persisting response (21% and 26%, respectively). Children did not relapse after 2 years from initial treatment whereas adults did. Initial CR and prolonged B-cell depletion predicted sustained responses whereas prior splenectomy, age, sex, and duration of ITP did not. No novel or substantial long-term clinical toxicity was observed. In summary, 21% to 26% of adults and children with chronic ITP treated with standard-dose rituximab maintained a treatment-free response for at least 5 years without major toxicity. These results can inform clinical decision-making.

Splenectomy as a curative treatment for immune thrombocytopenia: a retrospective analysis of 233 patients with a minimum follow up of 10 years.

The treatment of choice in steroid-resistant immune thrombocytopenia is still controversial due to the recent advent of new drugs (anti-CD20 antibodies and thrombopoietin mimetics) that have encouraged a generalized tendency to delay splenectomy. Consequently, it is extremely importance to define the efficacy and safety of splenectomy in the long term. We retrospectively analyzed the data of 233 patients affected by immune thrombocytopenia who underwent splenectomy between 1959 and 2001 in 6 European hematologic institutions and who have now a minimum follow up of ten years from surgery. Of the 233 patients, 180 (77%) achieved a complete response and 26 (11%) a response. Sixty-eight of 206 (33%) responsive patients relapsed, mostly (75%) within four years from first response. In 92 patients (39.5%), further treatment was required after splenectomy that was effective in 76 cases (83%). In 138 patients (59%), response was maintained free of any treatment at last contact. No significant association between baseline characteristics and likelihood of stable response was found. Overall, 73 (31%) and 58 (25%) patients experienced at least one infectious or hemorrhagic complication, which was fatal in 2 and 3 patients, respectively. A stable response to splenectomy was associated with a lower rate of infections (P=0.004) and hemorrhages (P<0.0001). Thrombosis developed in 18 patients (8%) and was fatal in 4. Splenectomy achieved a long-term stable response in approximately 60% of cases. Complications mainly affected non-responding patients and were fatal in a minority.

Long-term safety and tolerability of romiplostim in patients with primary immune thrombocytopenia: a pooled analysis of 13 clinical trials.

BACKGROUND AND OBJECTIVES: Thrombopoietin receptor agonists (TPOra) are the only treatments for immune thrombocytopenia (ITP) for which evidence of efficacy and safety from randomized, placebo-controlled trials is available. We sought to determine the long-term tolerability of the TPOra romiplostim, with a particular focus on thrombosis, bleeding, bone marrow (BM) reticulin, neoplasms/haematological malignancies and fatal events. METHODS: Data from 13 romiplostim clinical trials in which 653 patients with ITP received romiplostim for up to 5 yr (921.5 patient-years) were pooled; subject incidence rates and exposure-adjusted event rates (per 100 patient-years) were calculated. RESULTS: The rate of thrombotic events (6% of patients, 7.5 events per 100 patient-years) did not appear to increase over time; 9 events were associated with platelet counts >400 × 10(9) /L and 10 with romiplostim doses exceeding current recommendations. Serious and grade ≥3 bleeding each occurred in approximately 8% of patients (~11 events per 100 patient-years). Adverse events of BM reticulin were recorded for 12 patients (1.8%, 1.3 events per 100 patient-years, confirmed by bone biopsy in ten patients) and BM collagen for one patient (0.2%, 0.1 event per 100 patient-years, confirmed by trichrome staining). Neoplasms and haematological malignancies occurred in 2.1% and 0.8% of patients, respectively (2.2 and 0.7 events per 100 patient-years). Fatal events occurred in 3.7% of patients (2.6 events per 100 patient-years, four events treatment-related). CONCLUSIONS: Romiplostim is the TPOra for which the longest duration of safety data is available. Our data demonstrate that long-term romiplostim treatment is well tolerated, with no new safety signals, even in patients treated for up to 5 yr.

Platelet-associated antibodies, cellular immunity and FCGR3a genotype influence the response to rituximab in immune thrombocytopenia.

Rituximab is widely used in autoimmune diseases including immune thrombocytopenia (ITP), although the mechanism of effect remains unclear. This study describes the effects of rituximab on platelet-associated antibodies (PA-APAs), B and T cell counts and clonality ( IGHV and TRG@ gene rearrangements), FCGR3A (FcγRIIIa) and FCGR2A (FcγRIIa) polymorphisms and correlation to anti-CD40 ligand (CD40L) response. PA-APA levels fell more frequently in responders (6/8) than in non-responders (2/10: P = 0·08-0·15). Two responders had no PA-APAs. Two non-responders with a fall in PA-APAs had very high CD8 levels. One non-responder had a B cell clone, one responder and one non-responder had a T cell clone. 15/16 patients had the same responses to rituximab and antiCD40L. Patients with FCGR3A V/V polymorphisms were more likely to respond to rituximab (P = 0·03). In summary, the fall in PA-APAs in responders confirms the humoural effect of rituximab. Failure to respond in patients with very high CD8 levels, despite PA-APA fall indicates a role for T cell-mediated platelet/megakaryocyte destruction. Concordance of response to anti-CD40L suggests autoantibody-producing cells are under T cell control. Finally, the effect of FCGR polymorphisms on response confirms the importance of FCGR-mediated depletion of B cells in autoimmunity. This has implications on the pathology of ITP as well as the immunological effect of B cell depletion.

Temsirolimus, an mTOR inhibitor, in combination with lower-dose clofarabine as salvage therapy for older patients with acute myeloid leukaemia: results of a phase II GIMEMA study (AML-1107).

The mammalian target of rapamycin (mTOR) signalling pathway has emerged as an important therapeutic target for acute myeloid leukaemia (AML). This study assessed the combination of temsirolimus, an mTOR inhibitor, and lower-dose clofarabine as salvage therapy in older patients with AML. Induction consisted of clofarabine 20mg/m(2) on days 1-5 and temsirolimus 25mg (flat dose) on days 1, 8 and 15. Patients achieving complete remission with (CR) or without (CRi) full haematological recovery could receive monthly temsirolimus maintenance. In 53 evaluable patients, the overall remission rate (ORR) was 21% (8% CR, 13% CRi). Median disease-free survival was 3·5months, and median overall survival was 4months (9·1months for responders). The most common non-haematological severe adverse events included infection (48%), febrile neutropenia (34%) and transaminitis (11%). The 30-d all-cause induction mortality was 13%. Laboratory data from 25 patients demonstrated that a >50%in vivo inhibition of S6 ribosomal protein phosphorylation was highly correlated with response rate (75% with inhibition versus 0% without inhibition; P=0·0001), suggesting that targeting the mTOR pathway is clinically relevant. The acceptable safety profile and the predictive value of target inhibition encourage further investigation of this novel regimen.

Immune thrombocytopenia: pathophysiologic and clinical update.

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by both reduced platelet survival and suppression of megakaryocyte and platelet development. It can either be primary or secondary to other autoimmune disorders, infections, vaccines, lymphoproliferative disorders, and drugs. Antibodies reacting against platelet glycoproteins are typical of ITP; these antibodies can mediate destruction of platelets by the monocyte-macrophage system as well as suppress megakaryocyte proliferation and maturation. Abnormalities of cell-mediated immunity are known to contribute to the pathologic process. Like many other autoimmune diseases, ITP has a T helper cell type 1 bias and a reduced activity of T-regulatory cells. Cytotoxic T cells may directly lyse platelets and possibly suppress megakaryopoiesis. Recent studies suggest that mesenchymal stem cells are dysfunctional in ITP and may contribute to an aberrant amplification of the autoimmune response. Significant advances in the treatment of chronic ITP have been witnessed in the past decade, first with the introduction of rituximab and more recently with the thrombopoietin-receptor agonists. While splenectomy is still considered the gold standard in this setting, effective medical therapy is now available for patients in whom surgery is not an option.

International consensus report on the investigation and management of primary immune thrombocytopenia.

Previously published guidelines for the diagnosis and management of primary immune thrombocytopenia (ITP) require updating largely due to the introduction of new classes of therapeutic agents, and a greater understanding of the disease pathophysiology. However, treatment-related decisions still remain principally dependent on clinical expertise or patient preference rather than high-quality clinical trial evidence. This consensus document aims to report on new data and provide consensus-based recommendations relating to diagnosis and treatment of ITP in adults, in children, and during pregnancy. The inclusion of summary tables within this document, supported by information tables in the online appendices, is intended to aid in clinical decision making.

Effectiveness, safety, and local progression after percutaneous laser ablation for hepatocellular carcinoma nodules up to 4 cm are not affected by tumor location.

OBJECTIVE: A high-risk location--defined as the tumor margin being less than 5 mm from large vessels or vital structures--represents a well-known limitation and contraindication for radiofrequency ablation of hepatocellular carcinoma (HCC) nodules. The aim of this study was to verify whether HCC nodule location negatively affected the outcome of percutaneous laser ablation in terms of its primary effectiveness, safety, and ability to prevent local tumor progression. MATERIALS AND METHODS: The medical records and radiologic examinations of 164 cirrhotic patients (90 men, 74 women; mean age ± SD, 68.6 ± 8.3 years) with 182 HCC nodules 4 cm or smaller (mean diameter ± SD, 2.7 ± 0.78 cm) that had been treated by laser ablation between 1996 and 2008 were retrospectively analyzed. One hundred six patients had 116 nodules in high-risk sites (high-risk group), whereas 58 patients had 66 tumors located elsewhere (standard-risk group). RESULTS: The overall median follow-up was 81 months (range, 6-144 months). The initial complete ablation rate per nodule did not significantly differ between the high-risk group and the standard-risk group (92.2% vs 95.5%, respectively; p = 0.2711). Rates of major complications (high-risk group vs standard-risk group, 1.9% [including one death] vs 0%) and minor complications (5.6% vs 1.0%) were not statistically different between the two groups. Only side effects were recorded significantly more often in high-risk patients than in standard-risk patients (31.5% vs 19.8%; p = 0.049). There was no significant difference in either cumulative incidence of local tumor progression (p = 0.499) or local tumor progression-free survival (p = 0.499, log rank test) between the high-risk group and the standard-risk group. CONCLUSION: When laser ablation is used to treat small HCC nodules, tumor location does not have a significant negative impact on the technique's primary effectiveness or safety or on its ability to achieve local control of disease.

Influence of ablative margin on local tumor progression and survival in patients with HCC ≤4 cm after laser ablation.

BACKGROUND: Ablation of the normal hepatic parenchyma surrounding the tumor (ablative margin [AM]) is necessary to prevent local tumor progression. PURPOSE: To assess the prognostic value of the ablative margin in patients with HCC ≤4 cm treated with US-guided laser ablation. MATERIAL AND METHODS: A cohort of 116 patients (53 women and 63 men, age range 42-82 years) with 132 HCC nodules ≤4 cm completely ablated by US-guided laser ablation was retrospectively analyzed. Rates of local tumor progression were compared using different ablative margin cut-offs (≥2.5, 5.0, 7.5, and 10.0 mm). Survival probability curves were obtained with the Kaplan-Meier method. RESULTS: The mean period of follow-up was 42 months (range 3-114 months). Local tumor progression was identified in 24 out of 132 lesions (18%), with an average time to progression of 24 months (range 6-36 months). A significant difference in local tumor progression was observed only if the ablative margin was ≥7.5 mm (7% vs. 23%, P = 0.020). Survival curves of patients with or without an ablative margin ≥7.5 mm were not different (P = 0.665; mean survival time 43.8 ± 3.1 and 46.8 ± 6.1 for an AM < or ≥7.5 mm, respectively). CONCLUSION: An ablative margin ≥7.5 mm turned out to be useful in preventing local tumor progression but did not affect long-term survival in patients with HCC ≤4 cm treated with laser ablation.

ITP: a historical perspective.

A clinical syndrome of bleeding and purpura consistent with a diagnosis of immune thrombocytopenia (ITP) was described by Werlhof long before platelets were identified as the cellular component of blood playing an essential role in primary haemostasis. Although a role for the spleen was suggested nearly a century ago, the pathophysiology of ITP has remained elusive for many decades. During this time Werlhof's disease was renamed idiopathic thrombocytopenic purpura, from which the acronym ITP originally derives. The second half of the 20th century brought recognition of the autoimmune components of ITP, and hence the need for a new standard nomenclature, which has recently been accepted. ITP currently stands for Immune Thrombocytopenia, a name that more appropriately reflects the low platelet count rather than purpura as the main feature of the disease, as well as to defining its underlying nature. Advances in our knowledge of the disease have paralleled the availability of new therapeutic agents, and we are now entering an era of pathophysiologically-based treatment options.

Effects of eradication of Helicobacter pylori infection in patients with immune thrombocytopenic purpura: a systematic review.

Whether the eradication of Helicobacter pylori infection can increase the platelet count in patients with immune thrombocytopenic purpura (ITP) is still a controversial issue. To provide evidence-based guidance, we performed a systematic review of the literature published in English, selecting articles reporting 15 or more total patients. We identified 25 studies including 1555 patients, of whom 696 were evaluable for the effects of H pylori eradication on platelet count. The weighted mean complete response (platelet count > or = 100 x 10(9)/L) and overall response (platelet count > or = 30 x 10(9)/L and at least doubling of the basal count) were 42.7% (95% confidence interval [CI], 31.8%-53.9%) and 50.3% (95% CI, 41.6%-59.0%), respectively. In 222 patients with a baseline platelet count less than 30 x 10(9)/L, the complete response rate was 20.1% (95% CI, 13.5%-26.7%) and the overall response rate was 35.2% (95% CI, 28.0%-42.4%). The response rate tended to be higher in countries with a high background prevalence of H pylori infection and in patients with milder degrees of thrombocytopenia. These findings suggest that the detection and eradication of H pylori infection should be considered in the work-up of patients with seemingly typical ITP.

Standardization of terminology, definitions and outcome criteria in immune thrombocytopenic purpura of adults and children: report from an international working group.

Diagnosis and management of immune thrombocytopenic purpura (ITP) remain largely dependent on clinical expertise and observations more than on evidence derived from clinical trials of high scientific quality. One major obstacle to the implementation of such studies and in producing reliable meta-analyses of existing data is a lack of consensus on standardized critical definitions, outcome criteria, and terminology. Moreover, the demand for comparative clinical trials has dramatically increased since the introduction of new classes of therapeutic agents, such as thrombopoietin receptor agonists, and innovative treatment modalities, such as anti-CD 20 antibodies. To overcome the present heterogeneity, an International Working Group of recognized expert clinicians convened a 2-day structured meeting (the Vicenza Consensus Conference) to define standard terminology and definitions for primary ITP and its different phases and criteria for the grading of severity, and clinically meaningful outcomes and response. These consensus criteria and definitions could be used by investigational clinical trials or cohort studies. Adoption of these recommendations would serve to improve communication among investigators, to enhance comparability among clinical trials, to facilitate meta-analyses and development of therapeutic guidelines, and to provide a standardized framework for regulatory agencies.

The genotype nucleophosmin mutated and FLT3-ITD negative is characterized by high bax/bcl-2 ratio and favourable outcome in acute myeloid leukaemia.

Nucleophosmin gene (NPM1) mutations characterize acute myeloid leukaemia (AML) with normal karyotype and frequently co-exist with FLT3 internal tandem duplications (ITD). We evaluated bcl-2, bax, NPM1 and FLT3-ITD in 222 AML patients. Bax/bcl-2 ratio >0.35 and NPM1 without FLT3-ITD were significantly associated (P = 0.0001). NPM1-mutated (mt)/FLT3-ITD negative patients showed a higher complete remission (CR) rate (90%, P = 0.0002) and a longer overall survival (OS, P = 0.00007). NPM1-mt/FLT3-ITD negative plus bax/bcl-2 > 0.35 subset showed a very high CR rate (96%), very long OS (P = 0.00005) and disease-free survival (P = 0.004). The favourable prognosis of NPM1-mt/FLT3-ITD negative patients might be explained by a higher bax/bcl-2 ratio.

Randomized trial of two schedules of low-dose gemtuzumab ozogamicin as induction monotherapy for newly diagnosed acute myeloid leukaemia in older patients not considered candidates for intensive chemotherapy. A phase II study of the EORTC and GIMEMA leukaemia groups (AML-19).

This study compared two schedules of low-dose gemtuzumab ozogamicin (GO) as induction monotherapy for untreated acute myeloid leukaemia in older patients unfit for intensive chemotherapy, to identify the more promising regimen for further study. Patients were randomized to receive either best supportive care or a course of GO according to one of two schedules: 3 mg/m(2) on days 1, 3 and 5 (arm A), or GO 6 mg/m(2) on day 1 and 3 mg/m(2) on day 8 (arm B). Primary endpoint was the rate of disease non-progression (DnP), defined as the proportion of patients either achieving a response or maintaining a stable disease following GO induction in each arm. Fifty-six patients were randomized in the two GO arms (A, n = 29; B, n = 27). The rate of DnP was 38% [90% confidence interval (CI), 23-55] in arm A, and 63% (90% CI, 45-78) in arm B. Peripheral cytopenias were the most common adverse events for both regimens. The all-cause early mortality rate was 14% in arm A and 11% in arm B. The day 1 + 8 schedule, which was associated with the highest rate of DnP, met the statistical criteria to be selected as the preferred regimen for phase III comparison with best supportive care.

Analysis of regulatory T-cell changes in patients with idiopathic thrombocytopenic purpura receiving B cell-depleting therapy with rituximab.

The effects of B-cell depletion with rituximab on regulatory T cells (Tregs) have not been determined. We investigated Tregs in patients receiving rituximab for chronic idiopathic thrombocytopenic purpura (ITP). The peripheral blood Tregs, identified as CD4+FOXP3+ T cells, were measured by flow cytometry prior to and after the immunotherapy. In addition, Tregs were analyzed for their usage of the T-cell receptor (TCR) beta-variable (VB) region gene as well as their regulatory function as assessed by cell proliferation assays. Pretreatment data revealed a reduced number and a defective suppressive capacity of Tregs in ITP patients compared with control individuals. In addition, Tregs showed a polyclonal spectratype. Patients, particularly responders, showed restored numbers of Tregs as well as a restored regulatory function upon treatment with rituximab. These results indicate that patients with active ITP have a defective T regulatory cell compartment that can be modulated by a B cell-targeted therapy.

Should medical treatment options be exhausted before splenectomy is performed in adult ITP patients? A debate.

Patients with primary immune thrombocytopenia (ITP) may require treatment to reduce the risk of serious bleeding if platelets remain consistently below 30 × 10(9)/L. While approximately 70-80% of patients respond to an initial course of corticosteroids, relapse is common. For steroid-refractory patients, there is a choice between surgical splenectomy and further medical treatments, based on many factors including the patient's bleeding history, fitness for surgery, comorbidities, tolerance of adverse events, lifestyle and preferences. Treatments that have traditionally been used (corticosteroids, azathioprine, danazol) suppress the immune system, potentially predisposing patients to infection. Recent insights into the underlying pathophysiology of the disease have allowed the development of targeted therapies, including the thrombopoietin (TPO) receptor agonists, which enhance platelet production. Phase III trials have found romiplostim and eltrombopag to be well tolerated and effective in elevating platelet counts and reducing bleeding in both splenectomised and nonsplenectomised patients with chronic ITP. The B-cell targeted monoclonal antibody rituximab has also shown some potential in this setting, although data are currently limited and there are toxicity concerns. The decision whether to proceed to splenectomy or try other medical therapies in corticosteroid-refractory patients remains patient-specific. Splenectomy has its risks (including perioperative and long-term risks), and relapse/nonresponse are relatively common, but it offers the possibility of cure in the majority of patients. However, newer treatments may potentially allow splenectomy to be deferred for prolonged periods, as well as providing alternative treatment options for patients who fail splenectomy.

Therapeutic strategies for hepatitis- and other infection-related immune thrombocytopenias.

Secondary thrombocytopenia may result from autoimmune diseases, lymphoproliferative disorders, infections, myelodysplastic syndromes, common variable immunodeficiency, agammaglobulinemia, hypogammaglobulinemia, immunoglobulin A deficiency, and drugs. The presence of thrombocytopenia may result from chronic infections with hepatitis C virus (HCV), human immunodeficiency virus (HIV), and Helicobacter pylori and should be considered in the differential diagnosis of immune thrombocytopenic purpura (ITP). Studies have shown that upon diagnosis of infections, treatment of the primary disease allows for stabilization of platelet counts. Antiviral therapy with highly active antiretroviral therapy (HAART) for HIV has aided in platelet recovery with a corresponding decrease in circulating viral load. In some cases, the use of a thrombopoietin (TPO) agonist, eltrombopag, normalizes platelet levels in patients with these infections. Thrombocytopenia in the absence of other disease symptoms requires screening for H pylori, especially in regions where there is a high prevalence of the disease, such as in Japan, and in cases where platelets have normalized following eradication therapy. In other regions where these infections are not prevalent, such testing is controversial.