Immune thrombocytopenia in children and adults: what's the same, what's different?

Knowledge map of thrombopoietin receptor agonists: A bibliometric analysis

Thrombopoietin receptor agonists (TPO-RAs) have been widely used to treat thrombocytopenia, however, a scientometric profile of TPO-RAs research is lacking. Methods: This study uses VOSviewer, CiteSpace, and R software to provide an overview of current research, highlight study hotspots, and predict future research directions of TPO-RAs. Results: One thousand seven hundred and nineteen relevant studies from 1993 to 2022 with 43962 citations were identified from the Web of Science Core Collection. Over three decades, the USA has been leading TPO-RAs publications. Industries and academic institutions have been actively involved in TPO-RAs research, with funding provided by pharmaceutical companies and public funding bodies. The most productive and cited journals are British Journal of Hematology and Blood, respectively. When author keywords were categorised into three clusters, i.e., cluster 1 (immune thrombocytopenic purpura (ITP)), cluster 2 (avatrombopag, lusutrombopag, and thrombocytopenia), and cluster 3 (TPO-RAs for ITP and off-label drug use), ITP was found to be the current research hotspot, while oral TPO-RAs and licensed or unlicensed drug indications of thrombocytopenic diseases require further investigation. Conclusion: This study has generated the knowledge map of TPO-RAs, which provides a dynamic roadmap for future research in this field.

Management of patients with immune thrombocytopenia in the Moscow region

Background. Idiopathic thrombocytopenic purpura (ITp) is an autoimmune disease characterized by antibody-mediated platelets destruction and impairment of their production, which manifests itself as: isolated thrombocytopenia, risk of spontaneous hemorrhage and bleeding of varying severity. ITp is a hematological, orphan disease with an incidence of 1–4 cases per 100,000 population. In modern literature, primary and secondary immune thrombocytopenias are distinguished. primary immune thrombocytopenia is a diagnosis of exclusion. To verify it, a certain diagnostic search is required.Aim. To evaluate clinical characteristics and treatment efficacy in patients with a confirmed primary immune thrombocytopenia in the Moscow region.Materials and methods. This article presents the results of an analysis of more than 2,400 outpatient records of patients diagnosed with thrombocytopenia (for the period from 2010 to 2022). Of these, about 400 confirmed clinical cases of various ITp forms were included in the ITp registry of the Moscow Region. All patients live in the Moscow region, receive treatment and are observed at the Center for Orphan diseases of the M.f. vladimirskiy Moscow Regional Research Clinical Institute.Results. There are 415 patients with a verified diagnosis of ITp in the register of the Moscow Region Center for Orphan diseases of the M.f. vladimirskiy Moscow Regional Research Clinical Institute (71 % (n = 294) are female). In 69.8 % (n = 290) of patients at the time of disease manifestation, hemorrhagic syndrome was recorded. As a first-line therapy, 92.8 % (n = 385) of patients received corticosteroids (prednisolone, methylprednisolone, dexamethasone), in the second-line therapy, 82 % (n = 340) of patients were recommended therapy with thrombopoietin receptor agonists (romiplostim, eltrombopag). The options for third-line therapy in patients with ITp are rituximab monotherapy, splenectomy, and intravenous immunoglobulin. Splenectomy was performed in 3.37 % (n = 14) of patients.Conclusion. when evaluating this register, the highest efficiency of thrombopoietin receptor agonists (romiplostim, eltrombopag) is observed – 84.1 % of the objective response.

Clinical Epidemiology, Treatment Outcome and Mortality Rate of Newly Diagnosed Immune Thrombocytopenia in Adult Multicentre Study in Malaysia

Background

Immune thrombocytopenia (ITP) is well characterized in Western, European and other Asia-Pacific countries. Nevertheless, the clinical epidemiology, treatment pattern and disease outcome of ITP in Malaysia are still limited and not well known.

Objective

This study aimed to describe the clinical epidemiology, treatment outcome and mortality of ITP patients in haematology tertiary multicentre in Malaysia.

Methods

Clinical and laboratory data of newly diagnosed adults with ITP by a platelet count <100 × 10⁹/L from January 2010 to December 2020 were identified and analyzed.

Results

Out of 500 incident ITP, 71.8% were females with a striking age preponderance of both genders among those aged 18–29 years. The median age was 36 years. The median platelet count was 17.5 × 10⁹/L, 23.0% had a secondary ITP, 34.6% had a Charlson’s score ≥1, 53.0% had bleeding symptoms including 2.2% intracranial bleedings (ICB). Helicobacter pylori screening was performed in <5% of cases. Persistency and chronicity rates were 13.6% and 41.8%, respectively. Most (80.6%) were treated at diagnosis onset and 31.2% needed second-line treatment. Throughout the course of ITP, 11.0% of patients died; 3.0% and 8.0% with bleeding and non-bleeding related ITP.

Conclusion

This study confirms the epidemiology of ITP is comparable with worldwide studies. Our incidence is high in the female, Malay ethnicity, primary ITP and events of cutaneous bleeding at ITP onset with 18–29 years predominance age group for both genders. The frequency of persistent and chronic ITP is inconsistent with published literature. Corticosteroids and immunotherapies are the most prescribed first-line and second-line pharmacological treatments. Thrombopoietin receptor agonist medications (TPO-RAs) usage is restricted and splenectomy is uncommon. Our mortality rate is similar but ITP related bleeding death is fourth-fold lower than previous studies. Mortality risks of our ITP patients include age ≥60 years, male, severe bleeding at presentation, CCI≥1 and secondary ITP.

Incidence of adult primary immune thrombocytopenia in England-An update

BACKGROUND

Adult primary immune thrombocytopenia (ITP) is a rare bleeding disorder of unknown cause. Recent estimates of its incidence and trend over time were acquired for England.

METHOD

The primary ITP population (using ICD 10 code D693 and excluding secondary ITP cases; positive predictive value: 82.6%) was sourced from NHS Digital inpatient and outpatient. Incidence rate (IR) for England and by age groups, sex, and regions were calculated and trends were assessed using average annual percent change (AAPC).

RESULTS

A total of 25 805 patients (mean age 59 years; females 57.8%) diagnosed between 2003 and 2014 was identified. IRs increased from 4.2/100 000 to 6.4/100 000 over this period (AAPC:4.3%). For all sex-specific age groups, the IRs significantly increased over time, except 18-29 years males. The greatest increase was among females aged 30-39 (AAPC:8.7%). In contrast, among ≥70 years, ITP was more common in males (highest IR among ≥80 years males: 23.9/100 000). England's average annual IR was 6.1/100 000 for 2010-14. An estimated 2.5/100 000 (based on UKITP Registry data) was estimated to require 1st line treatment whereas 2.4/100 000 would have 1st and 2nd line treatments within 6 months from diagnosis. IRs for London and East Midlands were the highest (6.5/100 000).

CONCLUSIONS

This study found a rising incidence of primary ITP, with sharp increases among young women and elderly men. These findings put in context the impact of ITP on patients' lives and the healthcare services in England, especially with 17%-50% who may develop chronic ITP and require long-term care.

A polygenic stacking classifier revealed the complicated platelet transcriptomic landscape of adult immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease with the typical symptom of a low platelet count in blood. ITP demonstrated age and sex biases in both occurrences and prognosis, and adult ITP was mainly induced by the living environments. The current diagnosis guideline lacks the integration of molecular heterogenicity. This study recruited the largest cohort of platelet transcriptome samples. A comprehensive procedure of feature selection, feature engineering, and stacking classification was carried out to detect the ITP biomarkers using RNA sequencing (RNA-seq) transcriptomes. The 40 detected biomarkers were loaded to train the final ITP detection model, with an overall accuracy 0.974. The biomarkers suggested that ITP onset may be associated with various transcribed components, including protein-coding genes, long intergenic non-coding RNA (lincRNA) genes, and pseudogenes with apparent transcriptions. The delivered ITP detection model may also be utilized as a complementary ITP diagnosis tool. The code and the example dataset is freely available on http://www.healthinformaticslab.org/supp/resources.php

HDAC3 single-nucleotide polymorphism rs2530223 is associated with increased susceptibility and severity of primary immune thrombocytopenia

INTRODUCTION

Primary immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disorder characterized by a low platelet count and increased risk of bleeding. We previously reported that low-dose chidamide, a histone deacetylase (HDAC) inhibitor, restores immune tolerance in patients with ITP. This study aimed to evaluate the association of a single-nucleotide polymorphism (SNP) rs2530223 in the HDAC3 gene with susceptibility to ITP and its clinical features.

METHODS

Patients with ITP and age-matched healthy participants were recruited for this case-control study. Genotyping of the HDAC3 rs2530223 polymorphism was performed using MassARRAY platform.

RESULTS

Individuals with T allele of HDAC3 rs2530223 exhibited a 1.472-fold increased risk of ITP susceptibility (OR 1.472; 95% CI 1.100-1.969; p = .009), while ones with the TT genotype under the codominant and recessive models, and the TC/TT genotypes under the dominant model all revealed increased risk of ITP susceptibility (dominant odds ratio[OR] 1.965; 95% CI: 1.046-3.656; p = .036; codominant OR 2.264; 95% CI 1.175-4.360; p = .015; and recessive OR 1.512; 95% CI 1.028-2.224; p = .036, respectively). Regarding platelet counts in ITP patients, we observed that the TC/TT genotypes exhibited a 3.932-fold increased risk for platelet (PLT) <30 × 10⁹ /L (OR 3.932; 95% CI 1.426-10.842; p = .008).

CONCLUSION

This study indicates that HDAC3 rs2530223 may be an important genetic factor related to ITP susceptibility and platelet count in ITP patients, providing new perspectives on disease progression, new therapeutic targets, and severity prediction.

Comparative efficacy of 19 drug therapies for patients with idiopathic thrombocytopenic purpura: a multiple-treatments network meta-analysis

Immune thrombocytopenia (ITP) is the most common clinical bleeding disorder with a high mortality rate and poor long-term survival quality in severe patients. There is controversy on how to choose the appropriate treatment. We systematically reviewed 19 randomized controlled trials (including 2615 participants) from January 1, 2015, to April 20, 2021. These investigations compared multiple drugs or their combinations in the therapeutic dose range for the treatment of ITP. The primary endpoint was based on the proportion of patients who responded to these therapies. The efficacy of eltrombopag plus rituximab, avatrombopag, dexamethasone plus anti-HP, and dexamethasone plus rhTPO was significantly higher than placebo (OR: 46.66, 29.44, 2.66, 1.86) or dexamethasone alone (OR: 46.22, 29.01, 2.22, 1.40). Placebo, oral immunosuppressants, and dexamethasone plus oseltamivir were less effective than the other ITP therapies tested. Eltrombopag plus rituximab may be the best choice when starting treatment for ITP.

Prevalence of primary immune thrombocytopenia and related healthcare resource utilization among Texas Medicaid beneficiaries

OBJECTIVE

To estimate the prevalence of primary immune thrombocytopenia (ITP) and describe ITP-associated healthcare resource utilization (HRU) among Texas Medicaid beneficiaries.

METHODS

A retrospective analysis using 2012-2015 Texas Medicaid claims data was conducted to estimate the annual prevalence of ITP. HRU was summarized for the 12-month period following initial ITP diagnosis. Logistic regression and generalized linear model were used to investigate predictors for all-cause and ITP-related HRU.

RESULTS

The average annual prevalence of ITP was 17.0 per 100,000 persons; higher among females vs males (17.4 vs 13.6 per 100,000) and highest among adults aged ≥ 65 years (36.7 per 100,000). Among 325 patients included in the HRU analyses, 49.2% received ITP therapies. More than half of patients had at least one all-cause emergency department (ED) visit (70.5%) and/or hospitalization (56.0%). One-third (32.6%) experienced at least one ITP-related ED visit and 40.3% had at least one ITP-related hospitalization. Compared to adults aged 18-49 with ITP, children aged 0-4 (odds ratio [OR] = 3.65, p = .0008) and aged 5-17 (OR = 2.68, p = .0074) were more likely to have an ITP-related hospitalization; children aged 0-4 (OR = 4.36, p = .0005) and children aged 5-17 (OR = 4.09, p = .0005) were more likely to have an ITP-related ED visit during the follow-up period.

CONCLUSION

There are 17 patients diagnosed with ITP for every 100,000 Texas Medicaid enrollees annually, with higher prevalence in females and the elderly. Children are more likely to experience hospitalizations and ED visits associated with ITP. ITP patients in Texas Medicaid utilize more healthcare resources compared to the general Medicaid population.

A modern reassessment of glycoprotein-specific direct platelet autoantibody testing in immune thrombocytopenia

Platelet autoantibody (PA) testing has previously shown poor sensitivity for immune thrombocytopenia (ITP) diagnosis, but no previous study used both 2011 American Society of Hematology (ASH) guidelines for ITP diagnosis and 2012 International Society on Thrombosis and Haemostasis (ISTH) PA testing recommendations. We therefore performed a comprehensive retrospective study of PA testing in adult patients with ITP strictly applying these criteria. Of 986 PA assays performed, 485 assays in 368 patients met criteria and were included. Sensitivity and specificity of a positive test result for diagnosis of active ITP (n = 228 patients) were 90% and 78%, respectively. Sensitivity and specificity of a negative test result for clinical remission (n = 61 assays) were 87% and 91%. Antibodies against both glycoprotein IIb (GPIIb)/IIIa and GPIb/IX were required for the presence of antibodies against GPIa/IIa in patients with ITP. Logistic regression analysis revealed that more positive autoantibodies predicted more severe disease (relative to nonsevere ITP, relative risk ratio for severe ITP and refractory ITP was 2.27 [P < .001] and 3.09 [P < .001], respectively, per additional autoantibody); however, serologic testing did not meaningfully predict treatment response to glucocorticoids, intravenous immunoglobulin, or thrombopoietin receptor agonists. Sixty-four patients with ITP had multiple PA assays performed longitudinally: all 10 patients achieving remission converted from positive to negative serologic results, and evidence for epitope spreading was observed in 35% of patients with ongoing active disease. In conclusion, glycoprotein-specific direct PA testing performed using ISTH recommendations in patients meeting ASH diagnostic criteria is sensitive and specific for ITP diagnosis and reliably confirms clinical remission. More glycoproteins targeted by autoantibodies predicts for more severe disease.

Clinical Phenotype and Response to Different Lines of Therapy in Elderly with Immune Thrombocytopenia: A Retrospective Study

Purpose

Insufficient knowledge of primary immune thrombocytopenia purpura (ITP) in the elderly, together with a lack of clinical trial data, has resulted in wide variation in treatments. Here, we present a study focused on clinical characteristics of ITP in older subjects at diagnosis integrated with the subsequent course of the disease and treatment history.

Methods

In a retrospective monoinstitutional study, we evaluated >65-year-old patients with primary ITP. Clinical characteristics at the time of diagnosis were described and analyzed. We aimed to delineate whether subsequent lines of therapy influenced the number of relapses. In addition to initial regimens, we reported subsequent treatments and the impact on relapse trends.

Results

A total of 50 patients (56% males, mean age 78 years) were included. With regard to clinical variables at diagnosis, statistical significance was found for Eastern Cooperative Oncology Group performance status 1 (46% of patients, p<0.0001), presence of three comorbidities (36% of patients, p<0.0001), World Health Organization grade 0 bleeding (46%, p=0.0001), and World Health Organization grade 1 bleeding (42%, p=0.0009). For bleeding sites, the most frequent were skin or mucosa (40%, p=0.0477). A decrease in platelet count was correlated with moderate or severe bleeding (ρ=-0.52, p=0.0001) and viscera or skin/mucosa + viscera site (ρ=-0.50, p=0.0002). Finally, a decreasing number of patients required treatment from first-line therapy to sixth (p<0.0001). Relapse was most frequent before second-line therapy (54%, p<0.0001) and less frequent before fivth and sixth (4%, p=0.0072; 2%, p=0.0027).

Conclusion

ITP in older age poses considerable challenges, so specific management strategies should be considered to optimize outcomes. Our findings provide evidence of an inverse relationship between lines of therapy and timing of relapses. This study does not exclude the possibility that agents used after first-line therapy may have an impact on the response and modify the unfavorable course of ITP.

Spleen: Development, anatomy and reactive lymphoid proliferations

The unique architecture of the spleen enables it to play a key role in the interactions between the circulatory, reticuloendothelial and immune systems. Response to circulating antigens in the setting of infection, autoimmune disease or other conditions may result in a range of benign lymphoid proliferations. Moreover, patients with underlying immune deficiency may also show abnormal lymphoid proliferations within the spleen. This review will highlight the histologic, immunophenotypic and clinical features of reactive lymphoid proliferations to aid in their recognition and provide a context for understanding their development in relation to normal splenic structure and function.

Comparative study between chronic immune thrombocytopenia patients and healthy population on Epstein-Barr virus infection status by polymerase chain reaction

BACKGROUND

Immune thrombocytopenia (ITP) has been known to be associated with assorted virus infections. This study aims to investigate the Epstein-Barr virus infection status in chronic ITP patients by real-time quantitative polymerase chain reaction.

METHODS

42 chronic ITP patients and 42 healthy donors were retrospectively included via propensity score matching with gender and age. EBV-DNA levels in whole blood of patients and donors were assessed by RT-qPCR, and correlations between virus load and platelet count were analyzed.

RESULTS

The positive rate of EBV-DNA in lymphocytes of chronic ITP patients was significantly higher than that in donors (52.4% vs 31.0%, p = 0.046). Platelet count [18(8-45)×10⁹/L] of patients with high virus load in lymphocytes was significantly lower than that [51(30-87)×10⁹/L] of patients with low virus load (p = 0.0001), whereas no difference was observed in platelet count between EBV-DNA-positive and negative subgroups of donors (p = 0.984). And a significant inverse correlation was observed between EBV-DNA levels in lymphocytes and platelet count (r = -0.4958, p = 0.019) in patients, which was independent from the presence of platelet-associated IgG.

CONCLUSIONS

EBV infection has a potential role in the development of chronic ITP. Identification and control of this underlying infection should be emphasized in the treatment of chronic ITP.

Delftia acidovorans pneumonia with lung cavities formation

Case Description

A 52-year-old female patient was admitted to our clinic with complaints of cough, sputum, fever and fatigue. The patient has been receiving immunosuppressive therapy for thrombocytopenic purpura for 5 years.

Clinical Finding

Inspiratory crackles were heard on both hemithorax. Oxygen saturation measured with the pulse oximeter was 97%. Chest X-ray showed diffuse reticular opacities that were more prominent in the upper zones of both lungs. WBC counts were 17,600 mm³ and Platelet counts were 29,000 mm³. Thorax CT showed that there were many thin-walled cavities and millimetric nodules accompanied by ground-glass infiltrates in the upper and middle lobes. Gram staining of bronchial fluid, taken by bronchoscopy, revealed Gram-negative bacilli and intense polymorphonuclear leukocytes. The bacteria were defined as Delftia acidovorans by BD Phoenix automated system.

Treatment and outcomes

The patient was hospitalized with suspicion of opportunistic pulmonary infections and cavitary lung disease. After the empirical treatment of intravenous piperacillin-tazobactam and oral clarithromycin, her clinical and radiological findings significantly regressed, and she was discharged with outpatient follow-up.

Clinical Relevance

This is the first example of cavitary pneumonia due to Delftia acidovorans in an immunocompromised patient. We would like to emphasize that Delftia pneumonia should be considered in the differential diagnosis of pulmonary cavitary involvement in such patients.

Platelet transfusion practices in immune thrombocytopenia related hospitalizations

BACKGROUND

The role of platelet transfusions in management of Immune Thrombocytopenia (ITP) remains controversial. Current guidelines recommend that platelet transfusions in ITP be reserved for catastrophic hemorrhage or invasive surgical procedures. This study assesses the nationwide platelet transfusion practices in hospitalized children and adults with ITP.

STUDY DESIGN AND METHODS

We studied hospitalizations with ITP as the primary admitting diagnosis from 2010-2014 in National Inpatient Sample (NIS), the largest all-payer inpatient database. Univariate and multivariable logistic regression analyses were used to determine factors predicting platelet transfusions. Sampling weights were applied to generate nationally representative estimates. Propensity score matching was used to perform sensitivity analyses.

RESULTS

From 2010 to 2014, there were 78,376 admissions with ITP as the primary admission diagnosis (mean ± SD age: 45 ± 27 years; females 56%, children [age < 18 years] 22%) and 282,285 with ITP as one of all the admission diagnoses. Overall, 27% admissions with ITP as primary (children 4%) and 15% admissions with ITP as one of all the diagnoses documented at least one platelet transfusion. On multivariable adjustment the following factors were associated with worsening disease severity and a higher odds of platelet transfusion, adult age (adjOR = 9.03, 95% CI = 7.40-11.02), male gender (adjOR = 1.21, 95% CI = 1.11-1.31), bleeding occurrence (intracranial/gastrointestinal/genitourinary/epistaxis) (adjOR = 1.78, 95% CI = 1.61-1.96), admission to rural non-teaching hospital (adjOR = 1.85, 95% CI = 1.52-2.22), and small bed-size hospital (adjOR = 1.23, 95% CI = 1.05-1.45). Of admissions reporting platelet transfusions, only 26% reported a bleeding complication, and 11% had a major operating-room surgery/procedure. Overall, 65% of transfused patients had neither bleeding nor a major operative procedure during the hospitalization. Admissions with platelet transfusions had a significantly longer mean length of hospitalization 2.2 days (95% CI = 1.96-2.41, p < 0.001), and accrued higher mean total hospital charges; $31,150 USD (95% CI = 27,644-34,656, p < 0.001). However, platelet transfusions were not associated with in-hospital mortality (adjOR = 1.02, 95% CI = 0.73-1.45, p = 0.892).

CONCLUSION

Platelets are administered to a small fraction of the hospitalized ITP patients. In a majority of these cases however, platelet usage does not appear to be concordant with the current guidelines or associated with improvement in clinical outcomes.

Clinical updates in adult immune thrombocytopenia

Immune thrombocytopenia (ITP) occurs in 2 to 4/100 000 adults and results in variable bleeding symptoms and thrombocytopenia. In the last decade, changes in our understanding of the pathophysiology of the disorder have led to the publication of new guidelines for the diagnosis and management of ITP and standards for terminology. Current evidence supports alternatives to splenectomy for second-line management of patients with persistently low platelet counts and bleeding. Long-term follow-up data suggest both efficacy and safety, in particular, for the thrombopoietin receptor agonists and the occurrence of late remissions. Follow-up of patients who have undergone splenectomy for ITP reveals significant potential risks that should be discussed with patients and may influence clinician and patient choice of second-line therapy. Novel therapeutics are in development to address ongoing treatment gaps.

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.

Case Reports of Idiopathic Thrombocytopenia Unresponsive to First-Line Therapies Treated With Traditional Herbal Medicines Based on Syndrome Differentiation

The objective of our study is to present two cases showing the effects of traditional Korean herbal medicines based on traditional Korean medicine (TKM) for the treatment of immune thrombocytopenic purpura (ITP). One patient showed no response to treatment with steroids and an immunosuppressive agent. Moreover, liver toxicity and side effects of steroids were evident. However, after he ceased conventional treatment and started to take an herbal medicine, his liver function normalized and the steroid side effects resolved. Ultimately, he achieved complete remission. Another patient with ITP had sustained remission after steroid therapy in childhood, but extensive uterine bleeding and thrombocytopenia recurred when she was 16 years old. She was managed with steroids again for 2 years, but severe side effects occurred, and eventually she ceased taking steroids. She refused a splenectomy, and was then treated with a herbal medicine for 7 months, ultimately leading to sustained remission again. Many patients with resistance to first-line treatments tend to be reluctant to undergo a splenectomy, considered a standard second-line treatment. In conclusion, herbal medicines, based on TKM, may offer alternative treatments for persistent or chronic ITP that is resistant to existing first-line treatments.