Advances in Diagnosis and Treatments for Immune Thrombocytopenia

Recommendations for the management of acute immune thrombocytopenia in children. A Consensus Conference from the Italian Association of Pediatric Hematology and Oncology

BACKGROUND

Immune thrombocytopenia (ITP) is an acquired immune-mediated bleeding disorder characterized by isolated thrombocytopenia. Its estimated yearly incidence in the pediatric population is 1.9-6.4/100,000. ITP in children is usually a self-limiting and benign disorder. The clinical management of children with ITP often remains controversial, as robust randomized trials on the management of this disorder are lacking. Treatments vary widely in clinical practice and existing guidelines from hematology societies on clinical management offer indications based largely on expert opinion rather than strong evidence.

MATERIALS AND METHODS

The Coagulative Disorder Working Group of the Italian Association of Pediatric Hematology and Oncology (AIEOP) developed this document to collect shared expert opinions on the management of newly diagnosed ITP, updating previous guidelines and providing recommendations to pediatricians. Each statement has been given a score expressing the strength of evidence, appropriateness and agreement among participants.

RESULTS

Clear-cut definitions of the clinical phases of the disease and clinical response are stated. Recommendations are given regarding the classification of bleeding symptoms, evaluation of bleeding risk, diagnosis, and prognostic factors. Specific recommendations for treatment include indications for first-line (intravenous immunoglobulins, steroids) and second-line (combined therapy, thrombopoietin receptor agonists, immunosuppressive drugs, rituximab) therapeutic agents, as well as hemorrhagic emergency and supportive treatment, including emergency splenectomy. The optimal follow-up schedule, the relation between ITP and vaccines and health-related quality-of-life issues are also discussed.

DISCUSSION

The panel achieved broad consensus on issues related to how to treat children with newly diagnosed ITP, providing a comprehensive review of all relevant clinical aspects.

Trimethylamine-N-oxide (TMAO) and basic fibroblast growth factor (bFGF) are possibly involved in corticosteroid resistance in adult patients with immune thrombocytopenia

PURPOSE

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by accelerated platelet clearance. Gut dysbiosis was associated with its pathogenesis, but the underlying mechanisms have not been fully elucidated. Patients with ITP exhibit varying degrees of responsiveness to corticosteroid treatment. Therefore, prognostic indexes for corticosteroid responsiveness in ITP could offer valuable guidance for clinical practices.

METHODS

The present study examined the signature of six types of gut-microbiota metabolites and forty-eight types of cytokines, chemokines, and growth factors and their clinical significance in patients with ITP.

RESULTS

Both patients with good and poor corticosteroid responsiveness exhibited significantly elevated/suppressed secretion of twenty-two cyto(chemo)kins/growth factors in comparison to healthy controls. Additionally, patients with ITP demonstrated a significant decrease in plasma levels of trimethylamine-N-oxide (TMAO), which was found to be negatively correlated to circulating platelet counts, and positively correlated with Interleukin (IL)-1β and IL-18. Notably, patients who exhibited poor response to corticosteroid treatment displayed elevated levels of TMAO and basic fibroblast growth factor (bFGF) in comparison to responders. Additionally, we found that the amalgamation of TMAO, bFGF and interleukin (IL)-13 could serve as a valuable prognostic tool for predicting CS responsiveness.

CONCLUSION

Patients with ITP were characterized overall by an imbalanced secretion of cyto(cheo)kins/growth factors and inadequate levels of TMAO. The varying degrees of responsiveness to corticosteroid treatment can be attributed to different profiles of basic FGF and TMAO that might be related to overburdened oxidative stress and inflammasome overactivation, and ultimately mediate corticosteroid resistance.

Improving pharmacological activities of thrombopoietin mimetic peptide by genetic fusion to albumin-binding domain

OBJECTIVE

Thrombopoietin mimetic peptide (TMP), an analog of natural thrombopoietin, can be used to treat primary immune thrombocytopenia. However, the short half-life of TMP limits its application in clinics. The present study aimed to improve the stability and biological activity of TMP in vivo via genetic fusion to the albumin-binding protein domain (ABD).

RESULTS

TMP dimer was genetically fused to the N-terminal or C-terminal of ABD, denoted as TMP-TMP-ABD and ABD-TMP-TMP. A Trx-tag was used to improve the fusion proteins' expression levels effectively. ABD-fusion TMP proteins were produced in Escherichia coli and purified by Ni²⁺-NTA and SP ion exchange column. Albumin binding studies in vitro showed that the fusion proteins could effectively bind to serum albumin to extend their half-lives. The fusion proteins effectively induced platelet proliferation in healthy mice, and the platelet count was increased by more than 2.3-fold compared with the control group. The increased platelet count induced by the fusion proteins lasted 12 days compared with the control group. The increasing trend was maintained for 6 days before a decline occurred after the last injection in the fusion-protein-treated mice group.

CONCLUSIONS

ABD can effectively improve the stability and pharmacological activity of TMP by binding to serum albumin, and the ABD-fusion TMP protein can promote platelet formation in vivo.

Scoping Review on Epigenetic Mechanisms in Primary Immune Thrombocytopenia

Immune Thrombocytopenia (ITP) is an autoimmune blood disorder that involves multiple pathways responsible for the homeostasis of the immune system. Numerous pieces of literature have proposed the potential of immune-related genes as diagnostic and prognostic biomarkers, which mostly implicate the role of B cells and T cells in the pathogenesis of ITP. However, a more in-depth understanding is required of how these immune-related genes are regulated. Thus, this scoping review aims to collate evidence and further elucidate each possible epigenetics mechanism in the regulation of immunological pathways pertinent to the pathogenesis of ITP. This encompasses DNA methylation, histone modification, and non-coding RNA. A total of 41 studies were scrutinized to further clarify how each of the epigenetics mechanisms is related to the pathogenesis of ITP. Identifying epigenetics mechanisms will provide a new paradigm that may assist in the diagnosis and treatment of immune thrombocytopenia.

Treatment of immune thrombocytopenia in Australian adults: A multicenter retrospective observational study

Background

In Australia, prescribing restrictions limit access to internationally recommended second‐line therapies such as rituximab and thrombopoietin agonists (TPO‐A) (eltrombopag and romiplostim). Subsequent lines of therapy include an array of immunosuppressive and immune‐modulating agents directed by drug availability and physician and patient preference.

Objectives

The objective of the study was to describe the use of first and subsequent lines of treatment for adult immune thrombocytopenia (ITP) in Australia and to assess their effectiveness and tolerability.

Patients/Methods

A retrospective review of medical records was conducted of 322 patients treated for ITP at eight participating centers in Australia between 2013 and 2020. Data were analyzed by descriptive statistics and frequency distribution using pivot tables, and comparisons between centers were assessed using paired t tests.

Results

Mean age at diagnosis of ITP was 48.8 years (standard deviation [SD], 22.6) and 58.3% were women. Primary ITP was observed in 72% and secondary ITP in 28% of the patients; 95% of patients received first‐line treatment with prednisolone (76%), dexamethasone (15%), or intravenous immunoglobulin (48%) alone or in combination. Individuals with secondary ITP were less steroid dependent (72% vs. 76%) and required less treatment with a second‐line agent (47% vs. 58%) in the study sample. Over half (56%) of the cohort received treatment with one or more second‐line agents. The mean number of second‐line agents used for each patient was 1.9 (SD, 1.2). The most used second‐line therapy was rituximab, followed by etrombopag and splenectomy. These also generated the highest rates of complete response (60.3%, 72.1%, and 71.8% respectively). The most unfavorable side effect profiles were seen in long‐term corticosteroids and splenectomy.

Conclusion

A wide range of “second‐line” agents were used across centers with variable response rates and side effect profiles. Findings suggest greater effectiveness of rituximab and TPO‐A, supporting their use earlier in the treatment course of patients with ITP across Australia.

Stromal Derived Factor-1 Gene Polymorphism in Pediatric Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a multifactorial disease in which both environmental and genetic factors have been implicated. The study aimed to investigate a possible association of single nucleotide polymorphisms (SNPs rs266085 and rs2839693) in the stromal derived factor-1 (SDF-1) gene and its association to ITP and effect on ITP severity and response to treatment. Genomic DNA was extracted from peripheral blood and polymorphism in SDF-1 gene rs266085 and rs2839693 was analyzed using PCR-restriction fragment length polymorphism technique in DNA extracted from 60 children with ITP together with 90 healthy controls. On analysis of SDF-1 rs266085 polymorphism, there was a high frequency of CC genotype in cases than controls and that difference was significant at codominant, overdominant, and dominant models (P<0.05). Furthermore, carriers of the CC genotype were more susceptible to severe ITP at onset, steroid dependency, and chronicity than carriers of other genotypes (P<0.05). Otherwise, no significant differences between ITP patients and controls as regard SDF-1 rs2839693 genotypes and alleles, and we did not find a relation between this polymorphism and ITP severity, steroid dependency, or duration. SDF-1 gene rs266085 SNP C allele is associated with susceptibility to develop ITP as well as increases the risk for severe ITP at onset, chronic ITP and steroid dependency.

Parvovirus Infection and Thrombotic Thrombocytopenic Purpura in an Adult Patient With Sickle Cell Beta-Thalassemia

Parvovirus infection and thrombotic thrombocytopenic purpura (TTP) are rare manifestations in adults with sickle cell beta-thalassemia. Due to the lack of a clear demarcation between the complications related to sickle cell disease (SCD) and TTP, the diagnosis is often challenging. The treatment requirements for both these entities are divergent and complicated, thus necessitating a careful plan of action during atypical presentations. Here we present a case of a 22-year-old woman during the peripartum period with fever, generalized body aches, and large joint pains that soon evolved into labor. The patient’s history was suggestive of an undiagnosed and inherited blood disorder. The presentation of aplastic crisis-splenic sequestration during early adulthood is atypical for the SCD course in general populations. Moreover, as the patient’s clinical status deteriorated with blood transfusion, the diagnosis and management of a sickle cell crisis event and TTP added to the dilemma in the presence of non-classic parvovirus infection. Though the causation of TTP due to SCD-parvovirus infection is questionable, the treatment of the baseline sickle cell crisis with the novel supportive measures resolved the underlying complications in our patient, suggesting the causal effect. As a result of this, we emphasize the importance of being vigilant about such atypical presentations to avoid delays in diagnosis and treatment of such life-threatening emergencies like TTP.

Prevalence of Cytomegalovirus (CMV) and Epstein-Barr Virus (EBV) Subclinical Infection in Patients with Acute Immune Thrombocytopenic Purpura (ITP)

Background: Immune thrombocytopenic purpura (ITP) defined as a bleeding disorder in which the number and production of platelets reduced by the immune system; however, the destruction of peripheral blood platelets also occurs. Although its exact etiology and pathogenesis not already know, several studies have shown that Epstein-Barr virus (EBV) and cytomegalovirus (CMV) known as possible causative agents of ITP. This investigation aims to evaluate the presence of CMV and EBV in two groups of case and control by polymerase chain reaction (PCR).

Materials and Methods: we considered the presence of CMV and EBV in 48 acute ITP patients and 48 healthy people. Study participants were recruited from Ahvaz Shafa Hospital between 2017 and 2018 and the presence of two viruses was investigated by (PCR).

Results: Out of 48 acute ITP patients, the CMV DNA was detected from the blood of 12 (25%) patients and the EBV DNA from the blood of 2 (4.2%) other patients. In addition, only one patient was (2.1%) co-infected with CMV and EBV. In contrast, in 48 healthy subjects, 3 (6.6%) had CMV and none of the control group was infected with EBV.

Conclusion: Due to the presence of both EBV and CMV in the acute ITP patients in Ahvaz, they can be considered as factors in the progression of this disease. Therefore, consideration of the methods of elimination and treatment of these two viruses in these patients may be used as a treatment strategy in ITP patients in the future.

Effect of Cytokine Gene Polymorphisms on Eltrombopag Reactivity in Japanese Patients with Immune Thrombocytopenia

Background

Immune thrombocytopenic purpura (ITP) is an autoimmune disease characterized by low platelet counts resulting from antiplatelet autoantibodies. Analysis of polymorphisms in cytokine-encoding genes is important for understanding the pathophysiology of ITP and selecting appropriate treatments. We investigated associations between polymorphisms in cytokine-encoding genes and responses to therapy in Japanese patients with ITP.

Methods

The participants in this study comprised 153 patients with ITP and 70 healthy controls. We extracted data on sex, age, platelet counts, bleeding symptoms, and therapeutic responses, including those to prednisolone (PSL) and eltrombopag. Genomic DNA was isolated from peripheral blood and polymorphisms in TNF-α, IL-10, TGF-β₁, and IFN-γ genes were analyzed using the PCR-SSP method.

Results

Our results showed that the TGF-β₁ +869 C/C genotype might be related to ITP in Japanese patients. The IL-10 -592 C/C and A/A, -819 C/C and T/T, and -1082, -819, -592 ATA/ATA genotypes might be associated with reactivity to PSL. Furthermore, the IL-10 -592 C/A -819 C/T genotypes, IL-10 ACC/ATA genotype, and TGF-β₁ +869 T/T and T/C genotypes might be linked to the response to eltrombopag.

Conclusion

Our results indicate that analysis of polymorphisms in cytokine-encoding genes could aid in understanding PSL and eltrombopag responsiveness in Japanese patients with ITP.

Platelet desialylation and TFH cells-the novel pathway of immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by immune-mediated destruction of one's own platelets. The progression of thrombocytopenia involves an imbalance of platelet production and clearance. B cells can induce autoantibodies, and T cells contribute to the pathological progression as well. Some patients with ITP have a poor response to common first-line therapies. Recent studies have shown that a novel Fc-independent platelet clearance pathway is associated with poor prognosis in these patients. By this pathway, desialylated platelets can be cleared by Ashwell-Morell receptor (AMR) on hepatocytes. Research has demonstrated that patients with refractory ITP usually have a high level of desialylation, indicating the important role of sialylation on platelet membrane glycoprotein (GP) in patients with primary immune thrombocytopenia, and neuraminidase 1(NEU1) translocation might be involved in this process. Patients with ITP who are positive for anti-GPIbα antibodies have a poor prognosis, which indicates that anti-GPIbα antibodies are associated with this Fc-independent platelet clearance pathway. Experiments have proven that these antibodies could lead to the desialylation of GPs on platelets. The T follicular helper (TFH) cell level is related to the expression of the anti-GPIbα antibody, which indicates its role in the progression of desialylation. This review will discuss platelet clearance and production, especially the role of the anti-GPIbα antibody and desialylation in the pathophysiology of ITP and therapy for this disease.

First-in-patient study of hetrombopag in patients with chronic idiopathic thrombocytopenic purpura

BACKGROUND

Idiopathic thrombocytopenic purpura (ITP) especially refractory and (or) relapsed ITP, is a serious and global health burden and its clinical treatment is far from being satisfied. Hetrombopag is a novel, small-molecule thrombopoietin receptor agonist for the treatment of chronic idiopathic thrombocytopenic purpura (CITP).

OBJECTIVES

This first-in-patient study aimed to investigate the safety, pharmacokinetics, and anticipated therapeutic dose of hetrombopag in CITP patients.

METHODS

In this multicenter, first-in-patient study, CITP patients received hetrombopag in a dose escalation (2.5 mg/day, 5 mg/day, or 7.5 mg/day) cohort. All patients received hetrombopag in fasting condition once daily for 2 weeks.

RESULTS

Of 44 patients screened, 32 were enrolled and treated. Most adverse events were graded 1 to 2 (ie, mild to moderate), and the incidence and severity were similar for three study cohorts. The pharmacokinetics of hetrombopag were found to be nonlinear with greater than dose-proportional: 12.5% of patients (1/8) in the 2.5 mg/d cohort, 58.3% of patients (7/12) in the 5 mg/d cohort, 66.7% of patients (8/12) in the 7.5 mg/d cohort reached the primary study endpoint of a platelet count exceeding 50 × 109 /L on day 28.

CONCLUSION

Hetrombopag was well tolerated and preliminarily efficacious. Efficacy, safety, and pharmacokinetic data suggest that 7.5 mg hetrombopag once daily was the anticipated therapeutic dose of hetrombopag in CITP patients and has been recommended for investigation in a later confirmatory clinical study of hetrombopag.

Romiplostim and Eltrombopag in Immune Thrombocytopenia as a Second-Line Treatment

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by platelet count less than 100×10⁹/L and an increased risk of bleeding. The risk of bleeding increases in proportion with the degree of thrombocytopenia. Although several medications are used for primary thrombocytopenia treatment, refractoriness remains a concern. Romiplostim and eltrombopag, two relatively new drugs, have been shown to be successful in ITP treatment after standard treatment failure. The current guidelines recommend their use as a second-line treatment. In this article, we have tried to compare which of these two medications is the best option considering clinical effectiveness, cost-effectiveness, adverse effects, and the possibility of switching between them in case of ineffectiveness. The studies used in this article were found in the PubMed database. All the studies are limited to adults. Based on these studies, both medications seem to be a largely effective, safe option. Romiplostim appears to have slightly fewer adverse effects and higher costs. Switching between thrombopoietin receptor agonists (TRAs) is a successful way to overcome adverse effects and inadequacy according to the currently available literature. We believe that more detailed studies are needed to determine which of these drugs should be considered the first choice, to report long term efficacy and adverse effects, and to determine if treatment guidelines can change regarding the use of TRAs as first-line treatment.

More about the combination of rituximab, cyclosporine and dexamethasone in the treatment of chronic ITP. A useful option on an environment with limited resources

Treatment of chronic primary immune thrombocytopenia (ITP) is challenging especially with limited resources and therapy-related complications. This prospective interventional study assessed the efficacy and safety of triple therapy(TT4); a combination treatment of oral dexamethasone 40 mg for days1-4, oral cyclosporine A 2-3 mg/kg daily for 28 consecutive days and intravenous rituximab 100 mg for days7,14,21 and 28 among 40 patients with ITP who failed previous 2 or more treatment options. Our aim was to maintain platelet count ≥ 30 X 10⁹/L without any obvious bleeding at any point in the study. Platelet counts were assessed weekly for a month then monthly for 2 years to evaluate the long-term response. TT4 was well tolerated and induced a good response with a significant increase in the mean platelet count after the 1^st, 2^nd, 3^rd, and 4^thweek compared to the baseline. Patients with mean platelet count ≥ 30 X 10⁹/L at the 6^th month were 75% (30/40 patients). Treatment free survivals (TFS) at 12 and 24 months were 93.3% (28/30 patients) and 80% (24/30 patients) respectively. TT4 is an effective treatment option that maintained platelet count in the desired level and induced a higher sustained response, especially in an environment with limited resources.

Mechanisms and therapeutic prospects of thrombopoietin receptor agonists

The second-generation thrombopoietin (TPO) receptor agonists eltrombopag and romiplostim are potent activators of megakaryopoiesis and represent a growing treatment option for patients with thrombocytopenic hematological disorders. Both TPO receptor agonists have been approved worldwide for the treatment of children and adults with chronic immune thrombocytopenia. In the EU and USA, eltrombopag is approved for the treatment of patients with severe aplastic anemia who have had an insufficient response to immunosuppressive therapy and in the USA for the first-line treatment of severe aplastic anemia in combination with immunosuppressive therapy. Eltrombopag has also shown efficacy in several other disease settings, for example, chemotherapy-induced thrombocytopenia, selected inherited thrombocytopenias, and myelodysplastic syndromes. While both TPO receptor agonists stimulate TPO receptor signaling and enhance megakaryopoiesis, their vastly different biochemical structures bestow upon them markedly different molecular and functional properties. Here, we review and discuss results from preclinical and clinical studies on the functional and molecular mechanisms of action of this new class of drug.

Treatments for Primary Immune Thrombocytopenia: A Review

Immune thrombocytopenic purpura (ITP) is an autoimmune condition that affects nearly 1:10,000 people in the world. It is traditionally defined by a platelet count of less than 100 x 109L, but treatment typically depends on symptomology rather than on the platelet count itself. For primary idiopathic ITP, corticosteroids have been the standard first-line of treatment for symptomatic patients, with the addition of intravenous immune globulin (IVIG) or Rho(D) immune globulin (anti-RhD) for steroid-resistant cases. In cases of refractory or non-responsive ITP, second-line therapy includes splenectomy or rituximab, a monoclonal antibody against the CD20 antigen (anti-CD20). In patients who continue to have severe thrombocytopenia and symptomatic bleeding despite first- and second-line treatments, the diagnosis of "chronic refractory ITP" is appropriate, and third-line treatments are evaluated. This manuscript describes the efficacy of different treatment options for primary ITP and introduces the reader to various third-line options that are emerging as a means of treating chronic refractory ITP.

Use of Erbium Laser in the Treatment of a Patient with Acute Purulent Periostitis and a Resistant Form of Primary Immune Thrombocytopenia

In our article, we described a clinical case of a patient with an acute periostitis of the maxilla with a comorbidity (primary immune thrombocytopenia, resistant form) who was treated using laser technology allowing us to provide good results: an intensive regeneration process and a decreased risk of developing infection complications and unpleasant signs for the patient, such as postoperative edema and intraoperative and postoperative pain syndrome.

Mesenchymal stem cells improve platelet counts in mice with immune thrombocytopenia

Immune thrombocytopenia (ITP) is a common autoimmune bleeding disorder. The breakdown of immune tolerance (regulatory T [Treg] cells and suppressor cytokines) plays an important role in ITP pathophysiology, especially in refractory ITP. Bone marrow-derived mesenchymal stem cells (BM-MSCs) show immunomodulatory properties and have been extensively utilized for autoimmune diseases. However, it has not been fully elucidated how BM-MSCs affect ITP. In this study, we explore the therapeutic mechanism of BM-MSCs on ITP in mice. Dose-escalation passive ITP mice were inducted by injection of MWReg30. BALB/c mice were randomly divided into two groups: ITP with BM-MSC transplantation and ITP controls. The serum levels of cytokines (interleukin 10 [IL-10] and transforming growth factor-β1 [TGF-β1]) were examined by enzyme-linked immunosorbent assays. The frequency of Treg cells in both peripheral blood and spleen mononuclear cells was analyzed by flow cytometry, and the forkhead box P3 (Foxp3) messenger RNA (mRNA) level was measured by real-time polymerase chain reaction. After BM-MSC treatment, the platelet (PLT) counts were significantly elevated. Meanwhile, cytokines (TGF-β1 and IL-10), the ratios of Treg cells, and the Foxp3 mRNA expression level were significantly higher in the BM-MSC group. Our results show that BM-MSCs can improve PLT counts mainly by secreting suppressive cytokines and upregulating Tregs, which may provide new therapeutic potential for human ITP.

Hemizygosity for the gene encoding glycoprotein Ibβ is not responsible for macrothrombocytopenia and bleeding in patients with 22q11 deletion syndrome

Essentials How thrombocytopenia relates to bleeding in 22q11 deletion syndrome (22q11DS) is not clear. Bleeding severity, platelet count and volume, and GPIBB were examined in patients with 22q11DS. Macrothrombocytopenia and bleeding typified imperfectly overlapping subsets of 22q11DS patients. GPIBB hemizygosity does not cause macrothrombocytopenia or bleeding in patients with 22q11DS. SUMMARY: Background and objectives Macrothrombocytopenia and bleeding are frequently associated with 22q11 deletion syndrome (22q11DS). GPIBB, which encodes the glycoprotein (GP) Ibβ subunit of GPIb-IX-V, is commonly deleted in patients with 22q11DS. Absence of functional GPIb-IX-V causes Bernard-Soulier syndrome, which is a severe bleeding disorder characterized by macrothrombocytopenia. Patients with 22q11DS are often obligate hemizygotes for GPIBB, and those with only a pathogenically disrupted copy of GPIBB present with Bernard-Soulier syndrome. The objective of this study was to determine how GPIBB hemizygosity and sequence variation relate to macrothrombocytopenia and bleeding in patients with 22q11DS who do not have Bernard-Soulier syndrome. Patients/methods We thoroughly characterized bleeding severity, mean platelet volume, platelet count and GPIBB copy number and sequence in patients with 22q11DS. Results and conclusions Macrothrombocytopenia and mild bleeding were observed in incompletely overlapping subsets of patients, and GPIBB copy number and sequence variation did not correlate with either macrothrombocytopenia or bleeding in patients with 22q11DS. These findings indicate that GPIBB hemizygosity does not result in either macrothrombocytopenia or bleeding in these patients. Alternative genetic causes of macrothrombocytopenia, potential causes of acquired thrombocytopenia and bleeding and ways in which platelet size, platelet count and GPIBB sequence information can be used to aid in the diagnosis and management of patients with 22q11DS are discussed.

A Narrative Approach to Describe QoL in Children With Chronic ITP

Objective: Primary immune thrombocytopenia (ITP) is a hemorrhagic disorder. Spontaneous recovery within 12 months occurs in the majority of pediatric patients. Nevertheless, in 20-30% of children the disease is chronic. The impact extends to the patients' families, whose everyday life, in terms of interpersonal relationships and financial status, is adversely affected. This study investigated the ability of a narrative instrument to improve the quality of life of pediatric chronic ITP patients and their families and quantified the familial burden imposed by the illness. Method: A quantitative survey and a narrative plot delivered through an online platform were adopted for the analysis. Results: Pediatricians of ten Italian Hematologic Centers explained the projects to patients and their family in the outpatient clinic. 70 caregivers of children with ITP filled the ad-hoc questionnaire. Data from 53 caregivers revealed the emotional impact of pediatric chronic ITP. The narrative approach highlighted the specific resources used by patients and their families to cope with the disease and its chronicity. Discussion: Caregivers underlined the need for "humaneness" in their interactions with clinical personnel. The majority of respondents provided positive feedback regarding the narrative project, defining the experience as "liberating" and improving their quality of life.

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.

Platelet-specific antibodies and differences in their expression in childhood immune thrombocytopenic purpura predicts clinical progression

IMPORTANCE

Immune thrombocytopenic purpura (ITP) is the most common bleeding disorder in children. Despite the highly spontaneously remission, still almost 20% of cases progress into chronic or refractory ITP, which seriously affects children's quality of life. Currently there is no method to predict the initial stage of childhood ITP.

OBJECTIVES

To evaluate platelet-specific antibodies and compare differences in their expression in childhood ITP to predict clinical progression.

METHODS

This is a single-center prospective cohort study from April 2014 to October 2015. We enrolled children initially diagnosed as ITP. Anti-GPIIb/IIIa and GPIb/IX antibodies were assayed by enzyme-linked immunoadsorbent assay (ELISA) and patients were followed up for 1 year. We also analyzed the relationship between the expression of the platelet-specific antibodies GPIIb/IIIa and GPIb/IX and their respective clinical prognoses.

RESULTS

Overall, 134 cases were enrolled including 77 boys and 57 girls with a median age of 19 months (range: 1 to 159). Positive rates of anti-platelet antibodies were 79.8%. After a 1-year observation period, 84.3% were diagnosed as newly diagnosed ITP and 13.4% were diagnosed as chronic ITP. Patients with anti-GPIIb/IIIa antibody had a higher risk for newly diagnosed ITP compared with patients who were anti-GPIb/IX antibody positive only (93% vs 25%, P = 0.005; 87% vs 25%, P = 0.014, respectively). There were more anti-GPIb/IX antibody positive only cases, diagnosed as chronic ITP, compared with anti-GPIIb/IIIa antibody positive only cases and double GPIIb/IIIa and GPIb/IX antibody positive cases (75% vs 7%, P = 0.005; 75% vs 13%, P = 0.014, respectively). Interpretation.

INTERPRETATION

Patients with anti-GPIIb/IIIa antibody (either single or double) were predicted to have a good prognosis, whereas anti-GPIb/ IX antibody only predicted a poor prognosis. These results should be confirmed via a larger cohort multicenter study.

Suprachoroidal Hemorrhage Simulating Melanoma in Idiopathic Thrombocytopenic Purpura

Background

We report a case of suprachoroidal hemorrhage simulating choroidal melanoma in a patient with idiopathic thrombocytopenic purpura (ITP).

Methods

Case report.

Results

A 79-year-old white male with a history of lung adenocarcinoma, ITP, and mild anemia noted blurred vision with photopsia and floaters in the right eye (OD) that worsened over 2 months. He was found to have a pigmented choroidal mass and was referred for evaluation of possible choroidal melanoma. Visual acuity was 20/30 in the affected right eye and 20/25 in the left eye (OS). There was mild vitreous hemorrhage and 2 pigmented peripheral choroidal tumors in the temporal and nasal fundus OD. B-scan ultrasonography confirmed 2 acoustically hollow tumors, and transillumination demonstrated no shadowing. Optical coherence tomography over the lesions revealed choroidal elevation with suprachoroidal scalloped surface. Fluorescein and indocyanine green angiography revealed normal choroidal fluorescence and cyanescence with no "double circulation" of melanoma and no dye blockage, suggesting a suprachoroidal location. These findings were suggestive of suprachoroidal hemorrhage rather than melanoma. The patient was managed conservatively, and the hemorrhages demonstrated spontaneous resolution.

Conclusion

Ocular manifestations of ITP are uncommon. Rarely, spontaneous suprachoroidal hemorrhage simulating melanoma can occur. A thorough clinical evaluation with multimodal imaging is critical to establishing the appropriate diagnosis.

Altered circulating T follicular helper cells in patients with chronic immune thrombocytopenia

The present study aimed to illuminate the role of circulating T follicular helper (TFH) cells in patients diagnosed with chronic immune thrombocytopenia (cITP). Fifty-four patients with cITP and 30 age-matched healthy control subjects were enrolled in the present study. TFH cell frequencies, expression of CD4⁺ TFH cell-associated cytokines, including interleukin (IL)-2, IL-4, IL-10 and IL-21 and associated regulatory mRNA expression levels including Bcl-6, c-Maf, Blimp-1 and PD-1 pre- and post-treatment with intravenous immunoglobulin and corticosteroids, were detected by flow cytometry, ELISA and reverse transcription-quantitative polymerase chain reaction, respectively. TFH cell frequencies of patients were significantly higher compared with healthy controls pre-treatment (P<0.05). Following treatment, significantly decreased percentages of TFH cells were present in cITP responders (P<0.05). Correlation analysis revealed that the number of TFH cells was negatively correlated with the platelet count in the peripheral blood. Furthermore, analysis of inflammatory cytokines indicated significant differences in serum interleukin (IL)-21 and IL-10 between pretreated patients and healthy controls (P<0.05). Additionally, transcription factor B-cell lymphoma (Bcl)-6, c-Maf and programmed death-ligand (PD)-1 mRNA expression levels were significantly different between cITP patients prior to treatment and the healthy controls (P<0.05). However, the expression levels of Bcl-6, C-Maf and PD-1 mRNA were significantly changed post-treatment (P<0.05). These data demonstrated that circulating TFH cells and CD4⁺ TFH cell-associated cytokines may serve a role in cITP. The findings suggest that the overactivation of TFH cells may contribute to the immunopathogenesis of cITP, thus blocking the pathway of TFH cells may be reasonable for therapeutic intervention.

Percentages of PD-1+CD4+T cells and PD-L1+DCs are increased and sPD-1 level is elevated in patients with immune thrombocytopenia

The present study is to measure the expression of programmed death (PD)-1 / programmed death ligand-1 (PD-L1) negative costimulatory molecules, soluble format sPD-1 in patients with immune thrombocytopenia (ITP), and to investigate their correlation with the secretion of cytokines. A total of 35 patients with ITP were included in the present study. Twenty healthy subjects who received physical examination at our hospital were included as control group. Peripheral blood was collected from all ITP patients and healthy subjects. Flow cytometry was performed to determine the percentages of PD-1+CD4+T cells and PD-L1+DCs in ITP patients and healthy subjects. Enzyme-linked immunosorbent assay was performed to measure the concentrations of interferon (IFN)-γ, interleukin (IL)-17 and sPD-1 in peripheral blood from ITP patients and healthy subjects. Percentages of PD-1+CD4+T cells and PD-L1+DCs in peripheral blood from ITP patients before treatment were significantly higher than that from healthy subjects, but were not different from those after treatment. Serum concentrations of IFN-γ, IL-17 and sPD-1 in ITP patients before treatment were significantly higher than those in healthy subjects, and these concentrations were significantly reduced after treatment. The concentration of sPD-1 was positively correlated with the concentration of IFN-γ, and negatively correlated with platelet count. Percentages of PD-1+CD4+T cells and PD-L1+DCs in ITP patients are higher than those in healthy subjects, but elevated sPD-1 concentration in the blood blocks PD-1/PD-L1 signaling pathway, leading to unaffected Th cell function. Elevated concentrations of IFN-γ and IL-17 in the blood may participate in the occurrence and development of ITP.

Circulating level of Th17 cells is associated with sensitivity to glucocorticoids in patients with immune thrombocytopenia

Glucocorticoids are a widely recognized first-line therapy for immune thrombocytopenia (ITP). However, some patients are unresponsive to glucocorticoid therapy for reasons that remain unclear. Accumulating evidence suggests that CD4⁺ T-cell abnormalities play a crucial role in the development of ITP. In the present study, we investigated peripheral blood CD4⁺ T cells, Th17-associated cytokines, and the mRNA expression level of Th17 transcription factor-RORγt-in patients with newly-diagnosed ITP before glucocorticoid therapy. The study involved 27 newly-diagnosed patients. Th17-cell levels in the peripheral blood of newly-diagnosed ITP patients were associated with responsiveness to glucocorticoid therapy. Newly-diagnosed ITP patients who were not sensitive to glucocorticoid treatment were found to have lower levels of Th17 cells. Quantifying Th17 cells may allow physicians to predict prognosis of glucocorticoid treatment and stratify therapy for those with ITP. This strategy may provide a new approach to the treatment of glucocorticoid-insensitive patients.

Development of a new knock-in mouse model and evaluation of pharmacological activities of lusutrombopag, a novel, nonpeptidyl small-molecule agonist of the human thrombopoietin receptor c-Mpl

Lusutrombopag (S-888711), an oral small-molecule thrombopoietin receptor (TPOR) agonist, has gained first approval as a drug to treat thrombocytopenia of chronic liver disease in patients undergoing elective invasive procedures in Japan. Preclinical studies were performed to evaluate its efficacy against megakaryopoiesis and thrombopoiesis. To investigate the proliferative activity and efficacy of megakaryocytic colony formation via human TPOR, lusutrombopag was applied to cultured human c-Mpl-expressing Ba/F3 (Ba/F3-hMpl) cells and human bone marrow-derived CD34-positive cells, respectively. Lusutrombopag caused a robust increase in Ba/F3-hMpl cells by activating pathways in a manner similar to that of thrombopoietin and induced colony-forming units-megakaryocyte and polyploid megakaryocytes in human CD34-positive cells. Because lusutrombopag has high species specificity for human TPOR, there was no suitable experimental animal model for drug evaluation, except for immunodeficient mouse-based xenograft models. Therefore, a novel genetically modified knock-in mouse, TPOR-Ki/Shi, was developed by replacing mouse Mpl with human-mouse chimera Mpl. In TPOR-Ki/Shi mice, lusutrombopag significantly increased circulating platelets in a dose-dependent manner during 21-day repeated oral administration. Histopathological study of the TPOR-Ki/Shi mice on day 22 also revealed a significant increase in megakaryocytes in the bone marrow. These results indicate that lusutrombopag acts on human TPOR to upregulate differentiation and proliferation of megakaryocytic cells, leading to platelet production.

Pathogenesis and Therapeutic Mechanisms in Immune Thrombocytopenia (ITP)

Immune thrombocytopenia (ITP) is a complex autoimmune disease characterized by low platelet counts. The pathogenesis of ITP remains unclear although both antibody-mediated and/or T cell-mediated platelet destruction are key processes. In addition, impairment of T cells, cytokine imbalances, and the contribution of the bone marrow niche have now been recognized to be important. Treatment strategies are aimed at the restoration of platelet counts compatible with adequate hemostasis rather than achieving physiological platelet counts. The first line treatments focus on the inhibition of autoantibody production and platelet degradation, whereas second-line treatments include immunosuppressive drugs, such as Rituximab, and splenectomy. Finally, third-line treatments aim to stimulate platelet production by megakaryocytes. This review discusses the pathophysiology of ITP and how the different treatment modalities affect the pathogenic mechanisms.