ITP and international guidelines: What do we know, what do we need?

Recent advances in the management of immune thrombocytopenic purpura (ITP): A comprehensive review

Autoimmune disorders place a substantial burden on the healthcare system all over the world affecting almost 3% to 8% of the population. Immune thrombocytopenic purpura (ITP), also known as idiopathic thrombocytopenic purpura, is a blood disorder in which the body immune system destroys platelets, leading to low platelet counts in the blood (peripheral blood platelet count < 150 × 109/L). Although the pathophysiology of ITP is not fully understood, it is believed to result from a complex interplay between hereditary and environmental variables. Certain factors, such as a low platelet count, history of bleeding, and certain comorbidities can increase the risk of severe bleeding in patients with ITP. Corticosteroids, intravenous immunoglobulin (IVIG), immunosuppressants, rituximab, and thrombopoietin receptor agonists (TPO-RAs) are some of the advanced treatments for ITP. Although these therapies may be successful, they also carry the risk of negative effects. Recently, significant advancements have been made in the understanding and treatment of ITP. There is still much to learn about the disease, and new, more effective treatments are needed. This comprehensive review offers a comprehensive assessment of recent advancements in ITP management, with a focus on active research projects, novel therapeutic targets, new treatment modalities, and areas of uncertainty and unmet needs. According to research, it is crucial to develop individualized treatment plans for ITP patients based on their age, platelet count, risk of bleeding, and comorbidities. The article also looks at how future developments in gene editing, bispecific antibody therapies, and cellular therapy may completely change the treatment of ITP.

Mechanism and Molecular Targets of Ejiao Siwu Decoction for Treating Primary Immune Thrombocytopenia Based on High-Performance Liquid Chromatograph, Network Pharmacology, Molecular Docking and Cytokines Validation

We explored the mechanisms and molecular targets of Ejiao Siwu Decoction (EJSW) for treating primary immune thrombocytopenia (ITP) using network pharmacology and molecular docking. Active compounds of EJSW were identified by high-performance liquid chromatography-diode array detector (HPLC-DAD) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) and their targets were obtained from HERB and SwissTargetPrediction, and ITP targets were obtained from Comparative Toxicogenomics Database (CTD) and GeneCards. STRING and Cytoscape were used for protein-protein interaction (PPI) network analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses by WebGestalt yielded a gene-pathway network, Autodock molecular docking was applied to screen targets and active compounds, and cytokines were detected using a cytometric bead array (CBA) human inflammation kit. We identified 14 compounds and 129 targets, and 1,726 ITP targets. RAC-alpha serine/threonine-protein kinase (AKT1), tumour necrosis factor (TNF), interleukin-6 (IL6), caspase-3 (CASP3) and tumour suppressor protein (TP53) were core targets (nodes and edges). Functional annotation identified cofactor binding and coenzyme binding, and 20 significantly enriched pathways. Active compounds of EJSW were successfully docked with ITP targets. Tumour necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) were upregulated in ITP patients, vascular endothelial growth factor A (VEGF-A) and vascular endothelial growth factor D (VEGF-D) were downregulated, and EJSW treatment reversed these trends. EJSW may regulate key ITP targets based on the in silico analyses, and protect vascular integrity through AGE-RAGE signalling, complement and coagulation cascades, and VEGF signalling by downregulating TNF-α, IL-1β and other inflammatory factors.

Associations of Gut Microbiota and Fatty Metabolism With Immune Thrombocytopenia

Objective

To determine whether gut microbiota, fatty metabolism and cytokines were associated with immune thrombocytopenia (ITP).

Methods

In total, 29 preliminarily diagnosed ITP patients and 33 healthy volunteers were enrolled. Fecal bacterial were analyzed based on 16S rRNA sequencing. Plasma cytokines and motabolites were analyzed using flow cytometry and liquid chromatography-mass spectrometry (LC-MS), respectively.

Results

Bacteroides, Phascolarctobacterium, and Lactobacillus were enriched at the genus level in ITP patients, while Ruminococcaceae UCG-002, Eubacterium coprostanoligeues, Megamonas, and Lachnospiraceae NC2004 were depleted. At the phylum level, the relative abundance of Proteobacteria and Chloroflexi increased in ITP patients, while Firmicutes, Actinobacteria, and the Firmicutes/Bacteroidetes ratio decreased. Plasma levels of 5-hydroxyeicosatetraenoic acid (5-HETE), 6-trans-12-epi-leukotriene B4 (6t,12e-LTB₄), and resolvin D2 (RvD₂) were upregulated, and stachydrine, dowicide A, dodecanoylcarnitine were downregulated in ITP patients. Furthermore, RvD₂ is positively correlated with order Bacteroidetes VC2.1 Bac22, 5-HETE is positively correlated with genus Azospirillum, and 6t,12e-LTB₄ is positively correlated with genus Cupriavidus. In addition, stachydrine is positively correlated with family Planococcaceae, dowicide A is positively correlated with class MVP-15, and dodecanoylcarnitine is positively correlated with order WCHB1-41. Plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were upregulated in ITP patients.

Conclusion

Our study revealed a relationship between microbiota and fatty metabolism in ITP. Gut microbiota may participate in the pathogenesis of ITP through affecting cytokine secretion, interfering with fatty metabolism.

Refractory primary immune thrombocytopenia (ITP): current clinical challenges and therapeutic perspectives

Chronic primary immune thrombocytopenia (ITP) can today benefit from multiple therapeutic approaches with proven clinical efficacy, including rituximab, thrombopoietin receptor agonists (TPO-RA), and splenectomy. However, some ITP patients are unresponsive to multiple lines of therapy with prolonged and severe thrombocytopenia. The diagnosis of refractory ITP is mainly performed by exclusion of other disorders and is based on the clinician's expertise. However, it significantly increases the risk of drug-related toxicity and of bleedings, including life-threatening events. The management of refractory ITP remains a major clinical challenge. Here, we provide an overview of the currently available treatment options, and we discuss the emerging rationale of new therapeutic approaches and their strategic combination. Particularly, combination strategies may target multiple pathogenetic mechanisms and trigger additive or synergistic effects. A series of best practices arising both from published studies and from real-life clinical experience is also included, aiming to optimize the management of refractory ITP.

Romiplostim in adults with newly diagnosed or persistent immune thrombocytopenia

Introduction: Three distinct phases are recognized in immune thrombocytopenia (ITP): newly diagnosed (≤3 months after diagnosis), persistent (>3-12 months after diagnosis), and chronic (>12 months). Several international guidelines/expert recommendations have been released in the past 2 years regarding the treatment of newly diagnosed/persistent ITP. Areas covered: Across the guidelines/expert recommendations, thrombopoietin receptor agonists (TPO-RAs), including romiplostim (the focus of this review), are recommended in newly diagnosed or persistent ITP for patients who fail to respond to corticosteroids or intravenous immunoglobulin (or where these are contraindicated). To identify data relating to romiplostim in adults with newly diagnosed or persistent ITP, we conducted a search of PubMed (with no time limit applied) and abstracts from 2019 EHA/ASH meetings using the term 'romiplostim.' Expert opinion: The findings from nine clinical trials, six real-world studies and ten case reports provide insight into the early use of romiplostim, which could help to reduce exposure to the adverse effects associated with prolonged corticosteroid use, as well as reduce the risk of severe bleeding. Additionally, given the durable responses observed in patients with newly diagnosed/persistent ITP, as well as the potential for treatment-free responses following discontinuation, romiplostim might help to avoid the need for subsequent treatment.

Why thromboembolism occurs in some patients with thrombocytopenia and treatment strategies

Platelets play such an important role in the process of thrombosis that patients with thrombocytopenia generally have an increased risk of bleeding. However, abnormal thrombotic events can sometimes occur in patients with thrombocytopenia, which is unusual and inexplicable. The treatments for thrombocytopenia and thromboembolism are usually contradictory. This review introduces the mechanisms of thromboembolism in patients with different types of thrombocytopenia and outlines treatment recommendations for the prevention and treatment of thrombosis. According to the cause of thrombocytopenia, this article addresses four etiologies, including inherited thrombocytopenia (Myh9-related disease, ANKRD26-associated thrombocytopenia, Glanzmann thrombasthenia, Bernard-Soulier syndrome), thrombotic microangiopathy (thrombotic thrombocytopenic purpura, atypical hemolytic uremic syndrome, hemolytic uremic syndrome, Hemolysis Elevated Liver enzymes and Low Platelets syndrome, disseminated intravascular coagulation), autoimmune-related thrombocytopenia (immune thrombocytopenic purpura, antiphospholipid syndrome, systemic lupus erythematosus), and acquired thrombocytopenia (Infection-induced thrombocytopenia and drug-induced thrombocytopenia, heparin-induced thrombocytopenia). We hope to provide more evidence for clinical applications and future research.

Cancer risk in patients with primary immune thrombocytopenia - A Swedish nationwide register study

BACKGROUND

Immune thrombocytopenia (ITP) is an autoimmune disease treated with immunosuppressive agents, thrombopoietin receptor agonists, immunomodulation drugs and/or splenectomy. Patients with ITP have been found to have increased risk ofhematological malignancies. Studies investigating stomach/liver cancer are contradictory and the risk of developing other solid tumors is largely unknown. We aimed at estimating risk of overall and organ-specific cancers in patients with primary ITP.

METHODS

The study population was Swedish patients with at least one ITP diagnosis recorded in the National Patient Register and a 1:10 matched comparison cohort from the population. The study period covers 1997-2016. The Cancer Register and the Cause of Death Register provided data on malignancies and deaths, respectively. Primary ITP was identified using an established algorithm. We used time-split Cox models to estimate hazard ratios (HRs) with 95 % confidence intervals (CIs), adjusted for age, sex, index-year, county, income, education, Charlson score and number of in- and outpatient contacts.

RESULTS

In total 66,134 individuals were included in the study. Patients with ITP had higher risk of gastro-intestinal, skin (all morphologies), lymphoid and hematological cancers. Adjusted HR (95 % CI) for cancer was 1.37 (1.27-1.48), with highest risk during the first year, but with increased risk remaining for up to 20 years for men. For women, the overall risk was increased during the first year, HR (95 % CI) 2.00 (1.55-2.60). A significantly increased liver cancer risk was seen up to 9 years after diagnosis.

CONCLUSION

Patients with primary ITP have higher risk of cancer than the population. The observed increased risk does not seem to be solely due to surveillance bias, but might be associated with ITP or its treatments. Treating hematologists need to have high index of suspicion for cancer.

Predicting bleeding risk in a Chinese immune thrombocytopenia (ITP) population: development and assessment of a new predictive nomogram

The aim of this study was to develop a model that could be used to forecast the bleeding risk of ITP based on proinflammatory and anti-inflammatory factors. One hundred ITP patients were recruited to build a new predictive nomogram, another eighty-eight ITP patients were enrolled as validation cohort, and data were collected from January 2016 to January 2019. Four demographic characteristics and fifteen clinical characteristics were taken into account. Eleven cytokines (IFN-γ, IL-1, IL-4, IL-6, IL-8, IL-10, IL-17A, IL-22, IL-23, TNF-α and TGF-β) were used to study and the levels of them were detected by using a cytometric bead array (CBA) human inflammation kit. The least absolute shrinkage and selection operator regression model was used to optimize feature selection. Multivariate logistic regression analysis was applied to build a new predictive nomogram based on the results of the least absolute shrinkage and selection operator regress ion model. The application of C-index, ROC curve, calibration plot, and decision curve analyses were used to assess the discrimination, calibration, and clinical practicability of the predictive model. Bootstrapping validation was used for testing and verifying the predictive model. After feature selection, cytokines IL-1, IL-6, IL-8, IL-23 and TGF-β were excluded, cytokines IFN-γ, IL-4, IL-10, IL-17A, IL-22, TGF-β, the count of PLT and the length of time of ITP were used as predictive factors in the predictive nomogram. The model showed good discrimination with a C-index of 0.82 (95% confidence interval 0.73376-0.90 624) in training cohortn and 0.89 (95% CI 0.868, 0.902) in validation cohort, an AUC of 0.795 in training cohort, 0.94 in validation cohort and good calibration. A high C-index value of 0.66 was reached in the interval validation assessment. Decision curve analysis showed that the bleeding risk nomogram was clinically useful when intervention was decided at the possibility threshold of 16-84%. The bleeding risk model based on IFN-γ, IL-4, IL-10, IL-17A, IL-22, TGF-β, the count of PLT and the length of time of ITP could be conveniently used to predict the bleeding risk of ITP.

Relation between mutations in the 5' UTR of ANKRD26 gene and inherited thrombocytopenia with predisposition to myeloid malignancies. An Egyptian study

Inherited thrombocytopenias are a heterogeneous group of diseases characterized by a reduced number of platelets and a bleeding tendency that ranges from very mild to life threatening especially in surgery. Mutations in the 5' untranslated region (UTR) of Ankirin repeat domain 26 (ANKRD26) are responsible for autosomal-dominant form of thrombocytopenia, that is known as ANKRD26-related thrombocytopenia (ANKRD26 RT), characterized by a moderate thrombocytopenia with mild propensity to bleeding and predisposition to hematological malignancies including AML and MDS. We included 90 unrelated patients with inherited thrombocytopenia. In addition, we investigated 45 patients with ITP. Peripheral blood and bone marrow samples were collected and examined and molecular detection of mutations in the 5︡ UTR of ANKRD26 gene was performed for all the patients. Also, screening of the mutation and development of myeloid malignancies in the extended series of the affected subjects was done. ANKRD26 mutations were identified in 10% of the patients with inherited thrombocytopenia. The most common types were c.128 G > A and c.127A>T, while no mutations were found in the ITP group. In those affected, the median number of platelets was 69 x10⁹/L (43-106) with normal MPV in most of the patients (9.4-11.6). There was a statistically significant increase in the unexpected high frequency of myeloid malignancies in the extended series of the mutated subjects compared with the ITP group-extended series (P < .001). So, we can conclude that ANKRD26 RT is associated with increased risk for developing myeloid malignancies and ANKRD26 mutations can represent a valuable tool for making therapeutic decisions.

Report of a 'consensus' on the lines of therapy for primary immune thrombocytopenia in adults, promoted by the Italian Gruppo di Studio delle Piastrine

Despite the publication in 2009 of a paper on 'terms and definitions of immune thrombocytopenia' (ITP), some unresolved issues remain and are reflected by the disagreement in the treatment suggested for primary ITP in adults. Considering that these disagreements could be ascribed to non-shared goals, we generated a 'consensus' on some terms, definitions, and assertions useful for classifying the different lines of treatment for primary ITP in adults according to their indications and goals. Agreement on the appropriateness of the single assertions was obtained by consensus for the following indicators: 1. classification of four 'lines of therapy'; 2. acceptance of the expression 'sequences of disease' for the indications of the respective four lines of treatment; 3_I . practicability of splenectomy; 3_Ib . acceptance, with only some exceptions, of a 'timing for elective splenectomy of 12 months'; and 4_a-d . 'goals of the four lines of therapy.' On the basis of the consensus, a classification of four lines of treatment for primary ITP in adults was produced. In our opinion, this classification, whose validity is not influenced by the recently published new guidelines of the American Society of Hematology (ASH) and reviews, could reduce the disagreement that still exists regarding the treatment of the disease.

Platelet to Lymphocyte Ratio and Glucocorticoid Resistance in Newly Diagnosed Primary Immune Thrombocytopenia: A Retrospective Cohort Study

Background

In China, evidence regarding to the association between platelet to lymphocyte ratio (PLR) and glucocorticoid (GC) resistance in participants with primary newly identified immune thrombocytopenia (ITP) is limited. We aimed to investigate whether PLR is independently linked with GC-resistant ITP.

Material/Methods

We non-selectively and consecutively collected 154 newly diagnosed ITPs. The start enrollment time and the end enrollment time were from March 2013 to June 2017. The independent and dependent variables were PLR measured at diagnosis and GC non-response. Other variables involved in the present work can be summarized as demographic data and factors that were correlated with PLR reported by published studies. Univariate and multivariate binary logistic regression model and sensitivity analysis were used to evaluate the associations between PLR and GC resistance.

Results

After adjusting covariates, PLR level was negatively associated with GC non-response [odds ratio (OR)=0.89, 95% confidence intervals (CI): 0.80 to 0.98], and supported by propensity score matching model (OR=0.74, 95%CI: 0.57 to 0.96]. Nonlinearity of PLR and GC resistance was observed whose inflection point was 5.08 (by 2-piecewise model). The OR and 95%CI on both sides of inflection point were 3.14 (0.81 to 12.21) and 0.81 (0.69 to 0.95), respectively. Subgroup analysis showed no significant differences from subgroups.

Conclusions

Threshold effect on PLR and GC resistance is observed. When PLR is larger than 5.08, a unit increase of PLR is independently associated with 19% reduction of GC resistance.

Efficacy of vitamin D plus calcium with/without alendronate on bone metabolism in immunologic thrombocytopenic purpura patients with steroid treatment: Nine-month results of a randomized, double-blinded, controlled trial

Bone loss is a prominent complication in immunologic thrombocytopenic purpura (ITP) patients with steroid treatment. Anti-osteoporotic medications are applied as a therapeutic strategy to prevent bone deterioration in ITP patients. However, the skeletal protective effect of alendronate (ALN) in ITP patients has been rarely reported. The present study was performed to determine whether ALN reduces bone loss in ITP patients. A total of 40 ITP patients with steroid treatment were randomized into a placebo group [n=20; caltrate D (CalD)] and an ALN (10 mg/day) + CalD group (n=20). The patients received CalD or CalD + ALN treatment for 9 months. The primary outcomes were bone mineral density (BMD) in the lumbar vertebrae (L1-L4), femoral neck and total hip, as well as bone metabolism markers. The results indicated that the BMD of the lumbar vertebrae (L1-L4), femoral neck and total hip was significantly increased after ALN + CalD treatment for at 6 and 9 months compared with the baseline. Compared with CalD treatment alone, CalD combined with ALN significantly elevated the BMD at the three skeletal sites at 9 months. Compared with the baseline levels or CalD treatment alone, ALN together with CalD treatment markedly reduced urinary Ca excretion and the serum levels of the bone resorption markers tartrate resistant acid phosphatase 5b and C-terminal telopeptides of type 1 collagen, at 9 months. In conclusion, treatment with ALN together with CalD significantly elevated the BMD at three skeletal sites, and inhibited urinary Ca excretion and the activity of bone resorption markers in patients with ITP.

Systematic literature review of treatments used for adult immune thrombocytopenia in the second-line setting

Immune thrombocytopenia (ITP) is a rare platelet disorder that is often persistent or chronic in adults. Patient management is dependent upon physician judgment and patient preference, given both the rarity of the condition and a paucity of high-quality clinical trial evidence to inform practice guidelines. A systematic literature review was conducted to provide an up-to-date summary of studies evaluating the safety and efficacy/effectiveness of therapies used to treat adults with primary ITP in the second-line setting. Using comprehensive search strings, several medical research databases were queried. Final abstraction was performed on 186 articles. Most (75%) studies were observational in nature; nearly half were conducted in Europe. Splenectomy was the most commonly studied (n = 83, 47%), followed by rituximab (n = 49, 26%) and the thrombopoietin-receptor agonists (TPO-RAs) romiplostim (n = 34, 18%) and eltrombopag (n = 24, 13%). Twelve prospective, randomized controlled trials (RCTs) with a placebo or standard-of-care arm evaluating the safety and efficacy of either rituximab or a TPO-RA were identified and described in detail. These trials provide important information on the safety and efficacy of these treatments, and in the absence of head-to-head data, offer insights on how these therapies compare with one another in treating adult ITP in the second-line setting. This review confirms that for most second-line ITP treatment options, there remains a lack of rigorous evidence derived from RCTs, and for many treatments, there is limited evidence of any kind. The need for additional research to guide treatment choices in this setting and greater use of standardized ITP terminology are highlighted.

Oral manifestations of thrombocytopaenia

The appearance in the mouth of haemorrhagic petechiae, ecchymoses or blood blisters with spontaneous bleeding is suggestive of a haemorrhagic disorder that may be caused either by functional impairment of platelets or of blood vessel walls, by an abnormal decrease in the number of circulating platelets (thrombocytopaenia), or by defects in the blood clotting mechanism. Thrombocytopaenia from decreased production or increased destruction of platelets may be caused by multiple factors including immune mediated mechanisms, drugs or infections.

A diagnosis of thrombocytopaenic purpura can be made when any other disease entity that might be causing the purpura is excluded on the basis of the medical history, the physical examination, a complete blood count and a peripheral blood smear.

In this paper, we outline the clinical features of oral thrombocytopaenic purpura and briefly discuss some aspects of its aetiopathogenesis and treatment.

Mesenchymal stem cell deficiency influences megakaryocytopoiesis through the TNFAIP3/NF-κB/SMAD pathway in patients with immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease. Mesenchymal stem cells (MSCs) play important roles in the physiology and homeostasis of the haematopoietic system, including supporting megakaryocytic differentiation from CD34⁺ haematopoietic progenitor cells. Tumour necrosis factor alpha-induced protein 3 (TNFAIP3, also termed A20) plays a key role in terminating NF-κB signalling. Human genetic studies showed that the polymorphisms of the TNFAIP3 gene may contribute to ITP susceptibility. In this study, we showed a significant decrease in TNFAIP3 and increase in NF-κB/SMAD7 in ITP-MSCs. In co-cultures with CD34⁺ cells, NF-κB was overexpressed in MSCs from healthy controls (HC-MSCs) after transfection with NFKBIA (IκB)-specific short hairpin (sh)RNAs, resulting in MSC deficiency and a reduction in megakaryocytic differentiation and thrombopoiesis. Knockdown of TNFAIP3 expression using TNFAIP3-specific shRNAs in HC-MSCs affected megakaryocytopoiesis. However, IKBKB knockdown corrected megakaryocytopoiesis inhibition in the ITP-MSCs by decreasing NF-κB expression. Amplified TNFAIP3 expression in ITP-MSCs by TNFAIP3 cDNA can facilitate megakaryocyte differentiation. shRNA-mediated knockdown of SMAD7 expression rescued the impaired MSC function in ITP patients. Therefore, we demonstrate that a pathological reduction in TNFAIP3 levels induced NF-κB/SMAD7 pathway activation, causing a deficiency in MSCs in ITP patients. The ability of ITP-MSCs to support megakaryocytic differentiation and thrombopoiesis of CD34⁺ cells was impaired.

Circulating myeloid-derived suppressor cells predict disease activity and treatment response in patients with immune thrombocytopenia

Immune thrombocytopenia (ITP) is a disease characterized by isolated thrombocytopenia. Abnormal effector T cell activation is an important mechanism in the pathogenesis of ITP. Regulatory T cells (Treg) have a strong immunosuppressive function for T cell activation and their importance in the pathophysiology and clinical treatment of ITP has been confirmed. Myeloid-derived suppressor cells (MDSCs) are other immunosuppressive cells, which can also suppress T cell activation by secreting arginase, iNOS and ROS, and are essential for Treg cells’ differentiation and maturation. Therefore, we speculate that MDSCs might also be involved in the immune-dysregulation mechanism of ITP. In this study, we tested MDSCs and Treg cells in peripheral blood samples of twenty-five ITP patients and ten healthy donors. We found that MDSCs and Treg cells decreased simultaneously in active ITP patients. Relapsed ITP patients showed lower MDSCs levels compared with new patients. All patients received immunosuppressive treatment including dexamethasone alone or in combination with intravenous immune globulin. We found that MDSCs’ level after treatment correlated with platelet recovery. Our study is the first that focused on MDSCs’ role in ITP. Based on our results, we concluded that circulating MDSCs could predict disease activity and treatment response in ITP patients. This preliminary conclusion indicates a substantial significance of MDSCs in the pathophysiology and clinical treatment of ITP, which deserves further investigation.

Goals defining therapy for primary immune thrombocytopenia in adults

: Discordances existing between the two most influential guidelines on the treatment of immune thrombocytopenia, the 2010 International Consensus Report and the 2011 America Society of Hematology guideline, continue to be reflected by the heterogeneity of clinical practice of the physicians who treat this disease. Aimed at overcoming these discordances, we hypothesized that they could be ascribed to nonshared treatment goals. We classify the indications for and goals of the various possible treatments available for adults with primary immune thrombocytopenia according to the line of treatment and the phase of disease. The resulting classification is useful for recognizing the appropriateness of a chosen treatment in individual patients. The classification proposed here could constitute the basis for greater agreement among future guidelines and, in the meanwhile, could help less expert physicians recognize the appropriateness of a treatment to choose in the single patient.

Update on the use of immunoglobulin in human disease: A review of evidence

Human immunoglobulin preparations for intravenous or subcutaneous administration are the cornerstone of treatment in patients with primary immunodeficiency diseases affecting the humoral immune system. Intravenous preparations have a number of important uses in the treatment of other diseases in humans as well, some for which acceptable treatment alternatives do not exist. We provide an update of the evidence-based guideline on immunoglobulin therapy, last published in 2006. Given the potential risks and inherent scarcity of human immunoglobulin, careful consideration of its indications and administration is warranted.

The platelet Fc receptor, FcγRIIa

Human platelets express FcγRIIa, the low-affinity receptor for the constant fragment (Fc) of immunoglobulin (Ig) G that is also found on neutrophils, monocytes, and macrophages. Engagement of this receptor on platelets by immune complexes triggers intracellular signaling events that lead to platelet activation and aggregation. Importantly these events occur in vivo, particularly in response to pathological immune complexes, and engagement of this receptor on platelets has been causally linked to disease pathology. In this review, we will highlight some of the key features of this receptor in the context of the platelet surface, and examine the functions of platelet FcγRIIa in normal hemostasis and in response to injury and infection. This review will also highlight pathological consequences of engagement of this receptor in platelet-based autoimmune disorders. Finally, we present some new data investigating whether levels of the extracellular ligand-binding region of platelet glycoprotein VI which is rapidly shed upon engagement of platelet FcγRIIa by autoantibodies, can report on the presence of pathological anti-heparin/platelet factor 4 immune complexes and thus identify patients with pathological autoantibodies who are at the greatest risk of developing life-threatening thrombosis in the setting of heparin-induced thrombocytopenia.

A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study to Determine the Effect of Romiplostim on Health-Related Quality of Life in Children with Primary Immune Thrombocytopenia and Associated Burden in Their Parents

BACKGROUND

Chronic immune thrombocytopenia (ITP) in children can negatively impact their health-related quality of life (HRQoL) and impose a burden on their parents. This study sought to examine the effect of romiplostim on HRQoL and parental burden in children with primary ITP.

PROCEDURE

This was a phase 3, randomized, double-blind, placebo-controlled study. Children aged <18 years with ITP ≥6 months were randomly assigned to receive romiplostim or placebo for 24 weeks. The Kids' ITP Tool (KIT) was used to measure HRQoL and was administered to patients and/or their parents at baseline and weeks 8, 16, and 25. Mean KIT scores at each assessment and mean changes in KIT scores from baseline were calculated overall by treatment group and platelet response status. Psychometric properties of the KIT were evaluated and the minimally important difference (MID) was estimated for different KIT versions.

RESULTS

Sixty-two patients (42 romiplostim and 20 placebo) were enrolled. Changes in KIT scores by treatment group showed numerically greater and more often statistically significant improvements from baseline to each assessment for children receiving romiplostim versus placebo. Mixed-effects analysis demonstrated statistically significantly greater reduction in parental burden from baseline in the romiplostim group versus placebo. Ranges for the MID were estimated as 9-13 points for the Child Self-Report version and 11-13 points for the Parent Impact version.

CONCLUSIONS

The treatment with romiplostim may be associated with improved HRQoL in children with primary ITP and reduced burden to their parents.

Role of romiplostim in splenectomized and nonsplenectomized patients with immune thrombocytopenia

Romiplostim is a thrombopoietin receptor agonist (TPO-RA) used for the treatment of adult primary immune thrombocytopenia (ITP). ITP is an autoimmune condition characterized by low platelet counts due to increased destruction and reduced platelet production. First-line interventions include corticosteroids, anti-D, and intravenous immunoglobulins, while second-line therapies comprise splenectomy, rituximab, cyclosporine A, and TPO-RAs. The recognition that compromised platelet production is a critical part of the pathogenesis of ITP prompted the development of therapeutic strategies based on the stimulation of the TPO receptor. TPO-RAs enhance megakaryocyte proliferation, increase platelet production, and lead to a reduction in bleeding episodes in ITP patients. This review will summarize current data on the TPO-RA romiplostim, with a particular focus on its relation to splenectomy.

'On-demand' romiplostim therapy in immune thrombocytopenia

WHAT IS KNOWN AND OBJECTIVE

Although thrombopoietin receptor agonists are a second-line treatment for refractory immune thrombocytopenia (ITP), we lack guidelines recommending maintenance modality in patients who achieve complete remission (CR).

CASE SUMMARY

We report a patient with refractory ITP who achieved CR on romiplostim. Obtaining romiplostim for 6 months of therapy, we decided to try extending this by modifying the standard treatment regimen. Romiplostim was successfully administered 'on-demand', only if the patient's platelet count dropped below 150 × 10⁹ /L, over a period of 12 months.

WHAT IS NEW AND CONCLUSION

The strategy of 'on-demand' therapy is a promising procedure for the maintenance of response, lowering costs and improving treatment safety.

[Efficacy and safety of high-dose dexamethasone combined with rhTPO for newly diagnosed adults with severe immune thrombocytopenia]

OBJECTIVE

To evaluate the efficacy and safety of high dose dexamethasone combined with recombinant human thrombopoietin (rhTPO) in adults with severe newly diagnosed immune thrombocytopenia (ITP).

METHODS

Forty-eight adult patients with severe ITP were randomized into two groups, experimental group and control group. The patients in experimental group were given high-dose dexamethasone combined with rhTPO treatment, the patients in control group were given single high-dose dexamethasone treatment. Platelet count, platelet increase, as well as the overall response rate were strictly observed in the process. At the same time, the patient's drug tolerance and any adverse drug reactions were observed.

RESULTS

The platelet counts and platelet increase of the patients in experimental group were significantly higher than that in control group (P<0.05) at day 3, 7, 14, 30. There was no significant difference in overall response rates between the two groups (34.8% vs 36.0%, 56.5% vs 48.0%, P>0.05) at day 3, 7. The overall response rates of experimental group at day 14, 30 were significantly higher than that of control group (91.3% vs 68.0%, 82.6% vs 52.0%, P<0.05). The muscle aches occurred in one patient in experimental group which was self-recovery without special treatment.

CONCLUSION

rhTPO combined with high-dose dexamethasone could rapidly increase the platelet count, reduce the risk of bleeding, and prolonge the effect with a low incidence of tolerable adverse events compared to single high-dose dexamethasone. rhTPO combined with high-dose dexamethasone could be a new therapeutic choice for severe primary ITP.

[Efficacy and safety of high-dose dexamethasone combined with rhTPO for newly diagnosed adults with severe immune thrombocytopenia]

OBJECTIVE

To evaluate the efficacy and safety of high dose dexamethasone combined with recombinant human thrombopoietin (rhTPO) in adults with severe newly diagnosed immune thrombocytopenia (ITP).

METHODS

Forty-eight adult patients with severe ITP were randomized into two groups, experimental group and control group. The patients in experimental group were given high-dose dexamethasone combined with rhTPO treatment, the patients in control group were given single high-dose dexamethasone treatment. Platelet count, platelet increase, as well as the overall response rate were strictly observed in the process. At the same time, the patient's drug tolerance and any adverse drug reactions were observed.

RESULTS

The platelet counts and platelet increase of the patients in experimental group were significantly higher than that in control group (P<0.05) at day 3, 7, 14, 30. There was no significant difference in overall response rates between the two groups (34.8% vs 36.0%, 56.5% vs 48.0%, P>0.05) at day 3, 7. The overall response rates of experimental group at day 14, 30 were significantly higher than that of control group (91.3% vs 68.0%, 82.6% vs 52.0%, P<0.05). The muscle aches occurred in one patient in experimental group which was self-recovery without special treatment.

CONCLUSION

rhTPO combined with high-dose dexamethasone could rapidly increase the platelet count, reduce the risk of bleeding, and prolonge the effect with a low incidence of tolerable adverse events compared to single high-dose dexamethasone. rhTPO combined with high-dose dexamethasone could be a new therapeutic choice for severe primary ITP.

[Clinical analysis of recombinant human thrombopoietin for 92 adults with severe primary immune thrombocytopenia]

目的

评价重组人血小板生成素（rhTPO）治疗成人重型原发免疫性血小板减少症（ITP)的疗效及安全性。

方法

对2012年5月至2014年5月期间收治的92例成人重型ITP患者的临床资料进行回顾性分析。其中新诊断ITP 7例、持续性ITP 29例、慢性ITP 56例，男35例、女57例，中位年龄34 (18~65）岁。全部患者接受rhTPO 300 U·kg⁻¹·d⁻¹×14 d治疗，停药后观察7 d。

结果

全部92例患者rhTPO治疗的总反应率为60.9%(56/92)，新诊断ITP、持续性ITP、慢性ITP患者总反应率分别为71.4%、62.1%、58.9%。所有患者治疗第4、7、14天与停药第7天中位PLT分别为27(5~49)、65(16~138)、133 (28~208)、67(15~134)×10⁹/L。获完全反应的患者PLT达到100×10⁹/L的中位时间为6(5~7)d, PLT达峰值中位时间为11(5~17)d，中位PLT峰值为194(132~274)×10⁹/L。患者性别、年龄、疾病分期、血小板膜糖蛋白特异性抗体表达及外周血CD19⁺B、CD3⁺CD4⁺T、CD3⁺CD8⁺T淋巴细胞数量均与疗效无相关性(P>0.05)。少数患者出现低热、肌肉酸痛、乏力、头晕，均自行恢复。

结论

rhTPO治疗成人重型ITP具有较好的疗效和安全性。

Platelets and platelet alloantigens: Lessons from human patients and animal models of fetal and neonatal alloimmune thrombocytopenia

Platelets play critical roles in hemostasis and thrombosis. Emerging evidence indicates that they are versatile cells and also involved in many other physiological processes and disease states. Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a life threatening bleeding disorder caused by fetal platelet destruction by maternal alloantibodies developed during pregnancy. Gene polymorphisms cause platelet surface protein incompatibilities between mother and fetus, and ultimately lead to maternal alloimmunization. FNAIT is the most common cause of intracranial hemorrhage in full-term infants and can also lead to intrauterine growth retardation and miscarriage. Proper diagnosis, prevention and treatment of FNAIT is challenging due to insufficient knowledge of the disease and a lack of routine screening as well as its frequent occurrence in first pregnancies. Given the ethical difficulties in performing basic research on human fetuses and neonates, animal models are essential to improve our understanding of the pathogenesis and treatment of FNAIT. The aim of this review is to provide an overview on platelets, hemostasis and thrombocytopenia with a focus on the advancements made in FNAIT by utilizing animal models.