Risk factors for bleeding, including platelet count threshold, in newly diagnosed immune thrombocytopenia adults

Quercetin, a key active ingredient of Jianpi Zishen Xiehuo Formula, suppresses M1 macrophage polarization and platelet phagocytosis by inhibiting STAT3 activation based on network pharmacology

Primary immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disease, and abnormal M1 macrophage polarization participates in the pathogenesis of ITP. Jianpi Zishen Xiehuo (JZX) Formula has a good therapeutic effect on ITP. However, its key active ingredients and molecular mechanisms remain unclear. In this study, we explored the key active ingredients and potential targets of JZX in treating ITP using network pharmacology combined with in vitro experimental verification. A total of 157 active ingredients of JZX were identified from public databases, and quercetin was the most important one. One hundred sixty-five intersection targets of active ingredients in JZX, ITP, and macrophage polarization were obtained by Venn diagram. The top three potential targets were signal transducer and activator of transcription 3 (STAT3), protein kinase B (PKB/AKT) 1, and c-JUN through protein-protein interaction analysis. Molecular docking showed that quercetin had strong binding affinities with them all. In vitro experiment, CD16+ monocytes increased in ITP patients compared with healthy controls, which indicated a M1/M2 polarization imbalance in ITP. The expression levels of M1 polarization markers, CD86, CD80, and inducible nitric oxide synthase (iNOS), M1 polarization-associated cytokines, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), and antibody-opsonized platelet phagocytosis significantly increased in THP-1 macrophages stimulated with lipopolysaccharide (LPS). Quercetin markedly inhibited the expressions of M1 markers, decreased the levels of TNF-α and IL-6, and down-regulated the phosphorylated STAT3 (p-STAT3) protein, which confirmed the prediction by network pharmacology and molecular docking. Importantly, quercetin significantly reduced the phagocytosis of antibody opsonised platelet. In conclusion, quercetin suppressed platelet phagocytosis in M1 macrophages via its anti-inflammatory effects and may serve as a potential drug for the treatment of ITP. Quercetin could be a key ingredient for JZX against ITP.

Risk-based and individualised management of bleeding and thrombotic events in adults with primary immune thrombocytopenia (ITP)

Although bleeding is one of the main symptoms of primary immune thrombocytopenia (ITP), risk factors for bleeding have yet to be fully established. Low platelet count (PC; <20-30 × 109 /L) is generally indicative of increased risk of bleeding. However, PC and bleeding events cannot be fully correlated; many other patient- and disease-related factors are thought to contribute to increased bleeding risk. Furthermore, even though ITP patients have thrombocytopenia and are at increased risk of bleeding, ITP also carries higher risk of thrombotic events. Factors like older age and certain ITP treatments are associated with increased thrombotic risk. Women's health in ITP requires particular attention concerning haemorrhagic and thrombotic complications. Management of bleeding/thrombotic risk, and eventually antithrombotic therapies in ITP patients, should be based on individual risk profiles, using a tailored, patient-centric approach. Currently, evidence-based recommendations and validated tools are lacking to support decision-making and help clinicians weigh risk of bleeding against thrombosis. Moreover, evidence is lacking about optimal PC for achieving haemostasis in invasive procedures settings. Further research is needed to fully define risk factors for each event, enabling development of comprehensive risk stratification approaches. This review discusses risk-based and individualised management of bleeding and thrombosis risk in adults with primary ITP.

Difficult-to-treat primary immune thrombocytopenia in adults: Prevalence and burden. Results from the CARMEN-France registry

The aim of this study was to assess the prevalence and the burden of difficult-to-treat primary ITP (pITP), defined by the need for another ITP treatment after romiplostim and eltrombopag. Adult patients were selected in the prospective, real-world CARMEN-France registry up to December 2021. Out of 821 adult patients with pITP, 29 had difficult-to-treat ITP (3.5%; 95% confidence interval [CI]: 2.3%-4.8% in total; 7.6%; 95% CI: 4.9%-10.2% of patients needing ≥2nd line treatment). The 3-year cumulative incidence of bleeding, infection and thrombosis was 100%, 24.1% and 13.8% respectively. The median cumulative duration of hospital stays was 31 days (median follow-up: 30.3 months).

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.

How I diagnose and treat thrombocytopenia in geriatric patients

ABSTRACT

Thrombocytopenia in older individuals is a common but diagnostically challenging condition that has variable clinical impact to those who are affected. Diagnostic approach requires evaluation of the preexisting clinical conditions, detailed review of medications, and assessment for disorders that warrant urgent treatment. In this article, we describe a systematic approach to diagnosis of thrombocytopenia and present a schematic review for management strategies. Three clinical scenarios are presented that are relevant for their prevalence and management challenges in an older adult population. The first scenario addresses primary immune thrombocytopenia (ITP) and reviews different treatment options. The second one addresses complications of thrombocytopenia in management of the myelodysplastic syndrome. The last one reviews diagnostic challenges of drug-induced ITP.

Treatment of critical bleeding events in patients with immune thrombocytopenia: a protocol for a systematic review and meta-analysis

BACKGROUND

Critical bleeding events in adults and children with ITP are medical emergencies; however, evidence-based treatment protocols are lacking. Due to the severe thrombocytopenia, (typically platelet count less than 20 × 109/L), a critical bleed portends a high risk of death or disability. We plan to perform a systematic review and meta-analysis of treatments for critical bleeding in patients with ITP that will inform evidence-based recommendations.

METHODS

Literature searches will be conducted in four electronic databases: Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed. Eligible studies will be randomized controlled trials or observational studies that enrolled patients with ITP describing one or more interventions for the management of critical bleeding. Title and abstract screening, full-text screening, data extraction, and risk of bias evaluation will be conducted independently and in duplicate using Covidence and Excel. Outcomes will be pooled for meta-analysis where appropriate or summarized descriptively. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology will be used to evaluate the certainty of the evidence. Primary outcomes of interest will include frequency of critical bleeds, mortality and bleeding-related mortality, bleeding resolution, platelet count, and disability.

DISCUSSION

Evidence-based treatments for critical bleeding in patients with ITP are needed to improve patient outcomes and standardize care in the emergency setting.

SYSTEMATIC REVIEW REGISTRATION

CRD42020161206.

The many facets of immune-mediated thrombocytopenia: Principles of immunobiology and immunotherapy

Immune thrombocytopenia (ITP) is a rare autoimmune condition, due to peripheral platelet destruction through antibody-dependent cellular phagocytosis, complement-dependent cytotoxicity, cytotoxic T lymphocyte-mediated cytotoxicity, and megakaryopoiesis alteration. This condition may be idiopathic or triggered by drugs, vaccines, infections, cancers, autoimmune disorders and systemic diseases. Recent advances in our understanding of ITP immunobiology support the idea that other forms of thrombocytopenia, for instance, occurring after immunotherapy or cellular therapies, may share a common pathophysiology with possible therapeutic implications. If a decent pipeline of old and new agents is currently deployed for classical ITP, in other more complex immune-mediated thrombocytopenic disorders, clinical management is less harmonized and would deserve further prospective investigations. Here, we seek to provide a fresh overview of pathophysiology and current therapeutical algorithms for adult patients affected by this disorder with specific insights into poorly codified scenarios, including refractory ITP and post-immunotherapy/cellular therapy immune-mediated thrombocytopenia.

Immune thrombocytopenic purpura after influenza vaccine administration; a systematic review and meta-analysis

BACKGROUND

The American Society of Haematology defines immune thrombocytopenic purpura (ITP) as a common hematologic disorder characterized by a transient or long-term decrease in platelet counts (< 100 × 109/L.), purpura, and haemorrhagic episodes caused by antiplatelet autoantibodies, with the exclusion of other clinical conditions. We aimed to systematically determine the incidence of ITP in adults and children following influenza vaccination, the duration between vaccination and the occurrence of ITP, and to identify predictors of ITP after the vaccine.

METHODS

We searched PubMed, Cochrane Library, Google Scholar, Web of Science, Scopus, and Science Direct. We included primary studies that assessed the occurrence of immune thrombocytopenia in individuals who had received any influenza vaccine (primary or booster dose), regardless of the dosage, preparation, time of administration, or age of the participants. We excluded studies that were (a) Narrative, scoping, and umbrella reviews ;(b) studies with no accessible full text, abstract-only studies, or (c) Overlapping or unreliable data. The risk of bias in the included studies was assessed using the Joanna Briggs Institute (JBI) tool. We categorized studies for qualitative analysis based on study design. Descriptive statistics were used to summarize quantitative data, including the incidence of ITP after influenza vaccination.

RESULTS

Out of 729 articles retrieved from the database search, we included 24 studies. All patients identified and included in this systematic review presented with immune thrombocytopenia, determined by their platelet count. The period between vaccination and the occurrence of ITP ranged from (2:35 days). The mean duration was 13.5 days. The analysis revealed a statistically significant incidence rate ratio (IRR) = 1.85,95% CI [1.03-3.32] of ITP occurrence after 42 days.

CONCLUSIONS

Influenza-associated ITP is uncommon, self-limiting, non-life-threatening, and curable. None of the patients reported having severe adverse events or death. Further studies are required to confirm the exact incidence of the ITP to better understand the pathophysiology of ITP development post-influenza vaccination.

A fatal eosinophilic granulomatosis with polyangiitis case presenting intracerebral hemorrhage and thrombocytopenia

We report the case of a patient with eosinophilic granulomatosis with polyangiitis and unexplained thrombocytopenia that culminated in a fatal intracerebral hemorrhage. Because vessel damage associated with thrombocytopenia could be the leading cause of fatal hemorrhage, more urgent treatment of thrombocytopenia should be performed in such cases.

Hemostasis without clot formation: how platelets guard the vasculature in inflammation, infection, and malignancy

Platelets are key vascular effectors in hemostasis, with activation signals leading to fast recruitment, aggregation, and clot formation. The canonical process of hemostasis is well-characterized and shares many similarities with pathological thrombus formation. However, platelets are also crucially involved in the maintenance of vascular integrity under both steady-state and inflammatory conditions by ensuring blood vessel homeostasis and preventing microbleeds. In these settings, platelets use distinct receptors, signaling pathways, and ensuing effector functions to carry out their deeds. Instead of simply forming clots, they mainly act as individual sentinels that swiftly adapt their behavior to the local microenvironment. In this review, we summarize previously recognized and more recent studies that have elucidated how anucleate, small platelets manage to maintain vascular integrity when faced with challenges of infection, sterile inflammation, and even malignancy. We dissect how platelets are recruited to the vascular wall, how they identify sites of injury, and how they prevent hemorrhage as single cells. Furthermore, we discuss mechanisms and consequences of platelets' interaction with leukocytes and endothelial cells, the relevance of adhesion as well as signaling receptors, in particular immunoreceptor tyrosine-based activation motif receptors, and cross talk with the coagulation system. Finally, we outline how recent insights into inflammatory hemostasis and vascular integrity may aid in the development of novel therapeutic strategies to prevent hemorrhagic events and vascular dysfunction in patients who are critically ill.

Can Pseudothrombocytopenia be recognised at first look?

Our aim was to determine the laboratory parameters that distinguish pseudothrombocytopenia from true thrombocytopenia. A total of 107 patients who were referred to the adult hematology outpatient clinic with thrombocytopenia and subsequently diagnosed with acute myeloid leukaemia, immune thrombocytopenia and pseudothrombocytopenia were included in our study. Hemogram parameters on admission, platelet value in the control hemogram and peripheral smear findings were recorded. Forty three (40.2%) males and 64 (59.8%) females, were included in our study. There were 25 patients in the leukaemia group, 39 in the immune thrombocytopenia group and 43 in the pseudothrombocytopenia group. Control platelet value and red cell distribution width/platelet ratio were found to be statistically significantly different between the 3 groups. Receiver operating characteristic analysis based on platelet values showed that platelet value ≤ 38,000/µL (86% sensitivity, 78.1% specificity, P < .001), difference between 2 consecutively measured platelet levels ≤ 11. 000/µL (79.1% sensitivity, 79.7% specificity, P < .001), red cell distribution width/platelet ratio ≥ 0.413 (90.7% sensitivity, 78.1% specificity, P < .001) were found to be in favor of true thrombocytopenia. In the differentiation of pseudothrombocytopenia and true thrombocytopenia, the difference between the hemogram parameters at the time of admission and the platelet count in the control blood count may be guiding. This result may reduce patient and physician anxiety and prevent patient referral.

Insidious onset of spontaneous spinal epidural hematoma in immune thrombocytopenic purpura: a case-based review

INTRODUCTION

Spontaneous spinal epidural hematoma (SSEH) can result from various etiologies with a variable degree of neurological deficits. Here, we describe a rare case of SEH secondary to immune thrombocytopenic purpura (ITP) in a child and review the literature of SSEH caused by ITP.

CASE REPORT

A 9-year-old female who presented with rapid neurological decline, including bowel and bladder incontinence and paraparesis. A SSEH was observed extending from C2 to T6, causing a mass effect on the spinal cord. Her platelet count was only 7000/µL. Multidisciplinary care was established with neurosurgery, pediatric hematology, and pediatric surgery. The patient was managed emergently with splenectomy and surgical evacuation, with multilevel laminectomy and laminoplasty for evacuation of the hematoma. After a short course of rehabilitation, the patient regained all neurological function.

CONCLUSION

We report the first case of cervicothoracic SSEH secondary to ITP in a child managed with emergent splenectomy and surgical evacuation with multilevel lamoplasty. We also described the methods of timely diagnosis, urgent management, and overall prognosis of patients with this condition.

Risk of thrombotic events in immune thrombocytopenia patients treated with thrombopoietic agents: a systematic review and meta-analysis

BACKGROUND

Immune thrombocytopenia (ITP), which is a well-known hemorrhagic disorder characterized by low platelet counts, has been shown to be associated with the risk of thrombosis. Thrombopoietic agents (TAs) are extensively used as second-line treatments for ITP, effectively reducing the risk of hemorrhage. However, thrombosis, a potential adverse effect of TAs, raises clinical challenges.

METHODS

The MEDLINE(PubMed), Embase, and the Cochrane Library databases were systematically searched for relevant studies, including both single-arm trials and randomized controlled trials (RCTs), without language restrictions.

RESULTS

A total of 17 RCTs comprising 2,105 patients and 29 single-arm trials comprising 3,227 patients were included. In the single-arm meta-analysis, the pooled rate of overall thrombotic events in ITP patients receiving TAs was 2.2% (95% CI 1.0% - 3.7%). In RCTs, a higher incidence of thrombosis (33/1425 vs. 4/680) and higher risk ratios (RR) of overall, arterial, and venous thrombotic events (1.73, 95% CI [0.88, 3.39], P = 0.113; RR 1.98, 95% CI [0.80, 4.92], P = 0.141; RR 1.06, 95% CI [0.46, 2.41], P = 0.895, respectively) were observed in the TAs group than in the control group, although the differences were not significant. Subgroup analysis demonstrated that hetrombopag was the only TA with no increased thrombotic risk (rate 0.3% 95% CI [0.0 - 1.5%]; RR 0.76, 95% CI [0.03, 18.41], P = 0.864) compared to eltrombopag, avatrombopag, romiplostim, and rhTPO. Subgroup analyses also revealed that ITP patients with advanced age (3.7% vs. 1.3%, P = 0.132) or with a thrombotic history (3.0% vs. 1.4%, P = 0.257), and patients who received TAs therapy for a long duration (4.7% vs. 0.1%, P < 0.001) had an increased risk of thrombosis.

CONCLUSION

Our findings suggest ITP patients treated with TAs have a nonsignificantly higher risk of overall, arterial, and venous thrombotic events. Furthermore, hetrombopag is the recommended TA to avoid thrombophilia. Patients receiving long-term TAs, as well as elderly ITP patients or those with a history of thrombosis, face an increased thrombotic risk. In general, clinicians should consider potential thrombotic risks, address underlying risk factors, and ensure ongoing monitoring and follow-up when treating ITP patients with TAs.

Efficacy and Safety Analysis of Combination Therapy Consisting of Intravenous Immunoglobulin and Corticosteroids versus Respective Monotherapies in the Treatment of Relapsed ITP in Adults

Objective  In this study, we aimed to evaluate the efficacy and safety of combination therapy, consisting of intravenous immunoglobulin (IVIg) and corticosteroids, in comparison to respective monotherapies in the treatment of relapsed immune thrombocytopenia (ITP) in adults. Methods  A retrospective analysis of clinical data was conducted on 205 adult patients with relapsed ITP who received first-line combination therapy or monotherapy in multiple centers across China from January 2010 to December 2022. The study evaluated the patients' clinical characteristics, efficacy, and safety. Results  We found that the proportion of patients with platelet counts in complete response was significantly higher in the combination group (71.83%) compared with the IVIg group (43.48%) and the corticosteroids group (23.08%). The mean PLT _max in the combination group (178 × 10 ⁹ /L) was significantly higher than that in the IVIg group (109 × 10 ⁹ /L) and the corticosteroids group (76 × 10 ⁹ /L). Additionally, the average time for platelet counts to reach 30 × 10 ⁹ /L, 50 × 10 ⁹ /L, and 100 × 10 ⁹ /L in the combination group was significantly shorter than in the monotherapy groups. The proportion curves for reaching these platelet counts during treatment were also significantly different from those in the monotherapy groups. However, there were no significant differences in the effective rate, clinical characteristics, and adverse events among the three groups. Conclusion  We concluded that combining IVIg and corticosteroids was a more effective and faster treatment for relapsed ITP in adults than using either therapy alone. The findings of this study provided clinical evidence and reference for the use of first-line combination therapy in the treatment of relapsed ITP in adults.

Drug-Induced Thrombocytopenia Due to Nintedanib during Treatment of Idiopathic Pulmonary Fibrosis

Nintedanib is a tyrosine kinase inhibitor that was approved for the treatment of patients with idiopathic pulmonary fibrosis in 2014. The most common side effect of Nintedanib is diarrhea, and thrombocytopenia is a rare side effect of Nintedanib. The exact mechanism is unknown, and the literature lacks case reports of this phenomenon. Here, we report the case of a patient who developed thrombocytopenia 12 weeks after starting treatment with Nintedanib. The patient underwent an extensive work up for infectious, hematological, autoimmune, and neoplastic diseases. The patient's thrombocytopenia resolved following cessation of Nintedanib. This case is significant as it reports a rare side effect that might have detrimental consequences if not recognized and treated timely. Additionally, the onset of thrombocytopenia was delayed, 3 months after the initiation of Nintedanib. We also highlight the various literature regarding drug-induced thrombocytopenia and explore the necessary work-up needed to exclude other potential diagnoses. We hope to advocate for multidisciplinary teams to be aware of patients with pulmonary fibrosis on Nintedanib so that this adverse effect can be recognized promptly.

Predictive value of bone marrow megakaryocyte count for immunotherapeutic response in primary Sjögren's syndrome patients with severe immune thrombocytopenia: A single-center case-control study in China

OBJECTIVES

To investigate potential predictors of treatment response in primary Sjögren's syndrome (pSS) patients with severe immune thrombocytopenia (ITP), with a focus on bone marrow megakaryocyte (MK) count.

METHODS

This case-control study included patients with pSS and severe ITP who were admitted to Peking Union Medical College Hospital and met the 2002 AECG or 2016 American College of Rheumatology / European League Against Rheumatism criteria for SS. Patients who had overlap other connective tissue diseases and with thrombocytopenia that could be explained by other causes were excluded. Severe ITP was defined as platelet count <20 × 10⁹ /L. Response was evaluated at 3 months after treatment.

RESULTS

Sixty-eight eligible patients were included: 34 (50%) achieved complete remission (CR), 18 (26%) partial remission (PR) and 16 (24%) were non-responders (NRs). Fewer infections were found in the CR group (24%) than in the PR (50%) and NR (56%) groups (P = 0.04). The MK count (CR 32 vs PR 36 vs NR 4 per slide, P < 0.001) in the NR group was significantly lower than in the other groups. MK count >6.5 per slide predicted good treatment response, with 85.7% sensitivity, 88.1% specificity and 0.866 area under the curve. Logistic regression indicated that patients with more MKs were more likely to respond to immunotherapy (crude odds ratio [OR] 1.45, 95% CI 1.2-2.0, adjusted OR 1.68, 95% CI 1.2-2.7).

CONCLUSIONS

MK count predicted response to immunosuppressive treatment in pSS patients with severe ITP. These patients are recommended to have bone marrow aspiration before treatment initiation. Clinicians should be aware of screening for infections during clinical practice.

Assessment of circulating blood lymphocytes in adult patients on rituximab to treat immune thrombocytopenia: Circulating number of NK cells is associated with the response at 6 months

Immune thrombocytopenia (ITP) is defined by a low platelet count that can trigger potentially life-threatening haemorrhages. Three-quarters of adult patients exhibit persistent or chronic disease and require second-line treatments. Among these, rituximab, an anti-CD20 antibody, has yielded valuable results, with global responses in 60% of patients at 6 months and complete responses in 30% at 5 years. Factors predictive of response to ITP therapy would help physicians choose optimal treatments. We retrospectively analysed clinical courses, biological markers and blood lymphocyte subset numbers of 72 patients on rituximab to treat persistent/chronic ITP followed-up in our department between 2007 and 2021, divided into three groups according to the platelet count at 6 months: complete, partial or no response. Among all studied parameters, a low number of CD3^- CD16⁺ CD56⁺ circulating NK cells was associated with the complete response to rituximab. We also found that, after rituximab therapy, complete responders exhibited increased NK and decreased activated CD8⁺ T cell percentages. These results emphasize that the role played by NK cells in ITP remains incompletely known but that factors predictive of response to rituximab can be easily derived using blood lymphocyte subset data.

Sovleplenib (HMPL-523), a novel Syk inhibitor, for patients with primary immune thrombocytopenia in China: a randomised, double-blind, placebo-controlled, phase 1b/2 study

BACKGROUND

Spleen tyrosine kinase (Syk) inhibitor is a treatment option for primary immune thrombocytopenia. We aimed to evaluate the safety, tolerability, pharmacokinetics, preliminary activity, and recommended phase 2 dose of sovleplenib in patients with primary immune thrombocytopenia.

METHODS

This randomised, double-blind, placebo-controlled, phase 1b/2 study was conducted at nine hospitals in China. Eligible patients were aged 18-75 years, had an ECOG performance score of 0-1, had primary immune thrombocytopenia for more than 6 months, and did not respond or relapsed after previous first-line treatment or had poor response or postoperative relapse after a splenectomy. Dose-escalation (100 mg, 200 mg, or 300 mg given orally once a day) and dose-expansion phases (recommended phase 2 dose) each consisted of an 8-week, double-blind, placebo-controlled period in which patients were randomly assigned (3:1) to receive sovleplenib or placebo with an interactive web response system followed by a 16-week, open-label period with sovleplenib. Patients, investigators, and the sponsor were masked to treatment allocation during the first 8 weeks. The main efficacy endpoint was the proportion of patients whose platelet count reached 30 × 10⁹ platelets per L or higher and was double of the baseline at two consecutive visits during 0-8 weeks without rescue therapy. Efficacy was evaluated by intention-to-treat. This study is registered with ClinicalTrials.gov, NCT03951623.

FINDINGS

Between May 30, 2019, and April 22, 2021, 62 patients were assessed for eligibility and 45 (73%) were randomly assigned. Patients received at least one dose of the study drug during the 8-week double-blind period (placebo [n=11] and sovleplenib 100 mg [n=6], 200 mg [n=6], 300 mg [n=16], and 400 mg [n=6]; this group was added following the observation of no protocol-specified safety events at the previous doses). All participants were Asian; 18 (40%) of 45 were male and 27 (60%) were female. The median age was 40·0 years (IQR 33·0-50·0). Ten (29%) of 34 patients in sovleplenib groups versus five (45%) of 11 in the placebo group received concomitant anti-primary immune thrombocytopenia therapy. The recommended phase 2 dose was determined as 300 mg once a day. The proportion of patients who met the main efficacy endpoint were three (50%; 95% CI 12-88) in the 100 mg group, three (50%; 12-88) in the 200 mg group, ten (63%; 35-85) in the 300 mg group, and two (33%; 4-78) in the 400 mg group compared with one (9%; 0-41) in the placebo group. The overall response rate in the 300 mg group was 80% (16 of 20 who received continuous sovleplenib plus those who crossed over from placebo) and the durable response rate was 31% (11-59; five of 16) in the continuous sovleplenib 300 mg and 75% (19-99; three of four) crossed from placebo to sovleplenib during 0-24 weeks. During the 28-day safety evaluation period, two grade 2 or worse treatment-related treatment-emergent adverse events occurred in the sovleplenib groups (hypertriglyceridaemia and anaemia). During 0-8 weeks, the most frequent treatment-emergent adverse events were an increase in blood lactate dehydrogenase, haematuria, and urinary tract infection (seven [21%] of 34 in sovleplenib groups vs one [9%] of 11 in the placebo group); and occult blood-positive and hyperuricaemia (four [12%] vs three [27%] for each). No fatal treatment-emergent adverse events were recorded.

INTERPRETATION

Sovleplenib was well tolerated, and the recommended phase 2 dose showed a promising durable response in patients with primary immune thrombocytopenia, which provides evidence for future investigations. A phase 3 trial is ongoing (NCT05029635) to confirm the efficacy and safety of sovleplenib in patients with primary immune thrombocytopenia.

FUNDING

HUTCHMED.

Platelet function and soluble P-selectin in patients with primary immune thrombocytopenia

BACKGROUND

The bleeding phenotype in immune thrombocytopenia (ITP) is heterogeneous, but usually mild and only partly dependent on the severity of thrombocytopenia. Platelet reactivity has previously been suggested to underly the mild phenotype.

METHODS

Platelet function was assessed as basal and agonist-induced surface expression of P-selectin and activation of GPIIb/IIIa via flow cytometry, and soluble (s)P-selectin levels were assessed in plasma of 77 patients with primary ITP, 19 hemato-oncologic thrombocytopenic controls (TC) and 20 healthy controls (HC). The association of platelet function with laboratory and clinical parameters such as bleeding manifestations at inclusion and previous thrombosis was analyzed.

RESULTS

ITP patients showed tendency towards increased surface P-selectin and elevated levels of activated GPIIb/IIIa. Platelet activation after stimulation with all agonists including TRAP-6, ADP, arachidonic acid and CRP was decreased compared to HC. Compared to TC, only GPIIb/IIIa activation but not surface P-selectin was higher in ITP. Levels of soluble (s)P-selectin were significantly higher in ITP patients compared to TC, but similar to HC. Higher sP-selectin levels were associated with blood group O and current therapy, with highest levels in TPO-RA treated patients. Platelet reactivity was not associated with platelet count or size, platelet antibodies, treatment regime, or blood group. No correlation between platelet activation with the bleeding phenotype or previous thrombotic events could be observed.

CONCLUSION

ITP patients did not have hyper-reactive platelets compared to HC, but partly higher reactivity compared to TC. Further studies are needed to understand the underlying mechanism behind the bleeding and pro-thrombotic phenotype in ITP. 250/250.

Current approaches for the diagnosis and management of immune thrombocytopenia

Immune thrombocytopenia (ITP), is an acquired autoimmune disorder characterized by the destruction of platelets and megakaryocytes, resulting in thrombocytopenia (platelet count <100 × 10⁹/L). This review focuses on the diagnosis and current management of ITP. The diagnosis of ITP is based principally on the exclusion of other causes of isolated thrombocytopenia using patient history, physical examination, blood count, and evaluation of the peripheral blood film. The clinical treatment goals should be to resolve bleeding events and to prevent severe bleeding episodes. The platelet count should be improved to attain a minimum of > 20-30 × 10⁹/L. Therapy should be given as an inpatient in newly diagnosed ITP with a platelet count of > 20 × 10⁹/L or if there is active bleeding. Corticosteroids are considered the standard initial treatment for newly diagnosed patients. Subsequent medical therapies with robust evidence include thrombopoietin receptor agonists (TPO-RAs), rituximab and fostamatinib. Surgical therapy with splenectomy may be considered for patients failing medical therapy. The choice between therapy options is highly dependent upon patient values and preferences.

Older Adults and Immune Thrombocytopenia: Considerations for the Clinician

Many epidemiological studies have shown that the incidence of immune thrombocytopenia (ITP) increases after age 60 years and peaks in patients over age 80 years. Therefore, ITP is a concern for physicians taking care of older patients, especially regarding its diagnosis and management. The diagnostic work-up should exclude other causes of thrombocytopenia and secondary ITP, including myelodysplastic syndrome and drug-induced ITP. The treatment decision is influenced by an increased risk of bleeding, infectious diseases and thrombosis in this population and should take into account comorbidities and concomitant medications such as anticoagulant drugs. First-line treatment is based on short corticosteroids courses and intravenous immunoglobulin, which should be reserved for patients with more severe bleeding complications, with their higher risk of toxic effects as compared with younger patients. Second-line treatment should be tailored to the patient's history, comorbidities and preferences. Preferred second-line treatments are thrombopoietin receptor agonists for most groups and guidelines given their good efficacy/tolerance ratio, but the thrombotic risk is increased in older people. Other second-line options that can be good alternatives depending on the clinical context include rituximab, dapsone, fostamatinib or immunosuppressive drugs. Splenectomy is less often performed but remains an option for fit patients with chronic refractory disease. Emerging treatments such as Syk or Bruton tyrosine kinase inhibitors and FcRn antagonists are becoming available for ITP and may modify the treatment algorithm in the near future. The aim of this review is to describe the particularities of the diagnosis and treatment of ITP in older people, including the response and tolerance to the currently available drugs. We also discuss some situations related to co-morbidities that can frequently lead to adapt the management strategy in older patients.

How we treat primary immune thrombocytopenia in adults

Primary immune thrombocytopenia (ITP) is an immune-mediated bleeding disorder characterized by decreased platelet counts and an increased risk of bleeding. Multiple humoral and cellular immune abnormalities result in accelerated platelet destruction and suppressed platelet production in ITP. The diagnosis remains a clinical exclusion of other causes of thrombocytopenia. Treatment is not required except for patients with active bleeding, severe thrombocytopenia, or cases in need of invasive procedures. Corticosteroids, intravenous immunoglobulin, and anti-RhD immunoglobulin are the classical initial treatments for newly diagnosed ITP in adults, but these agents generally cannot induce a long-term response in most patients. Subsequent treatments for patients who fail the initial therapy include thrombopoietic agents, rituximab, fostamatinib, splenectomy, and several older immunosuppressive agents. Other potential therapeutic agents, such as inhibitors of Bruton's tyrosine kinase and neonatal Fc receptor, are currently under clinical evaluation. An optimized treatment strategy should aim at elevating the platelet counts to a safety level with minimal toxicity and improving patient health-related quality of life, and always needs to be tailored to the patients and disease phases. In this review, we address the concepts of adult ITP diagnosis and management and provide a comprehensive overview of current therapeutic strategies under general and specific situations.

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.

Developing and validating a mortality prediction model for ICH in ITP: a nationwide representative multicenter study

Intraparenchymal hemorrhage, platelet count, serious infections, severe bleeding events, and Glasgow coma scale predict poor prognosis.

A prognostic model was developed and validated, and an application was established.

Intracranial hemorrhage (ICH) is a rare and life-threatening hemorrhagic event in patients with immune thrombocytopenia (ITP). However, its mortality and related risk factors remain unclear. Herein, we conducted a nationwide multicenter real-world study of ICH in adult ITP patients. According to data from 27 centers in China from 2005 to 2020, the mortality rate from ICH was 33.80% (48/142) in ITP adults. We identified risk factors by logistic univariate and multivariate logistic regression for 30-day mortality in a training cohort of 107 patients as follows: intraparenchymal hemorrhage (IPH), platelet count ≤10 × 10⁹/L at ICH, a combination of serious infections, grade of preceding bleeding events, and Glasgow coma scale (GCS) level on admission. Accordingly, a prognostic model of 30-day mortality was developed based on the regression equation. Then, we evaluated the performance of the prognostic model through a bootstrap procedure for internal validation. Furthermore, an external validation with data from a test cohort with 35 patients from 11 other centers was conducted. The areas under the receiver operating characteristic (ROC) curves for the internal and external validation were 0.954 (95% confidence interval [CI], 0.910-0.998) and 0.942 (95% CI, 0.871-1.014), respectively. Both calibration plots illustrated a high degree of consistency in the estimated and observed risk. In addition, the decision curve analysis showed a considerable net benefit for patients. Thus, an application (47.94.162.105:8080/ich/) was established for users to predict 30-day mortality when ICH occurred in adult patients with ITP.

Diagnostic workup of inherited platelet disorders

Inherited platelet disorders (IPDs) can cause mucocutaneous bleeding due to impaired primary hemostatic function of platelets, thrombocytopenia, or both. Recent advances in molecular technology can help identify many genes related to platelet biology, control the overall steps of megakaryopoiesis, and cause IPD. In this article, currently available laboratory tools for diagnosing IPDs with the characteristic laboratory features of each IPD are reviewed, and a general diagnostic approach for the evaluation of IPD patients is presented.

Avatrombopag for the Treatment of Adult Patients with Chronic Immune Thrombocytopenia (cITP): Focus on Patient Selection and Perspectives

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by a reduced number of circulating platelets due to immune-mediated destruction and decreased platelet production in the bone marrow. Thrombopoietin receptor agonists (TPO-RAs) are highly effective and widely used in the treatment of patients with steroid treatment failure or dependency. Avatrombopag represents a new supplement to the TPO-RAs family. It was originally approved for the treatment of thrombocytopenia in patients with chronic liver disease who are scheduled to undergo an invasive procedure. However, labeled indications for avatrombopag have been relatively recently expanded to include treatment of chronic ITP in adults with insufficient response to the previous treatments. In this article, we provide an overview of pharmacodynamics and pharmacokinetics of avatrombopag as well as results of the clinical trials related to safety and efficacy of avatrombopag with a perspective on current clinical use. Available data so far suggests that avatrombopag can be effectively used in ITP patients and has a favorable safety profile. Though further studies are needed to affirm the efficacy and safety, avatrombopag has the potential to become a TPO agonist of choice for many patients with ITP.

The Extensive Regulation of MicroRNA in Immune Thrombocytopenia

MicroRNA (miRNA) is a small, single-stranded, non-coding RNA molecule that plays a variety of key roles in different biological processes through post-transcriptional regulation of gene expression. MiRNA has been proved to be a variety of cellular processes involved in development, differentiation, signal transduction, and is an important regulator of immune and autoimmune diseases. Therefore, it may act as potent modulators of the immune system and play an important role in the development of several autoimmune diseases. Immune thrombocytopenia (ITP) is an autoimmune systemic disease characterized by a low platelet count. Several studies suggest that like other autoimmune disorders, miRNAs are deeply involved in the pathogenesis of ITP, interacting with the function of innate and adaptive immune responses. In this review, we discuss emerging knowledge about the function of miRNAs in ITP and describe miRNAs in terms of their role in the immune system and autoimmune response. These findings suggest that miRNA may be a useful therapeutic target for ITP by regulating the immune system. In the future, we need to have a more comprehensive understanding of miRNAs and how they regulate the immune system of patients with ITP.

Method article: an in vitro blood flow model to advance the study of platelet adhesion utilizing a damaged endothelium

In vitro flow assays utilizing microfluidic devices are often used to study human platelets as an alternative to the costly animal models of hemostasis and thrombosis that may not accurately represent human platelet behavior in vivo. Here, we present a tunable in vitro model to study platelet behavior in human whole blood flow that includes both an inflamed, damaged endothelium and exposed extracellular matrix. We demonstrate that the model is adaptable across various anticoagulants, shear rates, and proteins for endothelial cell culture without the need for a complicated, custom-designed device. Furthermore, we verified the ability of this 'damaged endothelium' model as a screening method for potential anti-platelet or anti-thrombotic compounds using a P2Y₁₂ receptor antagonist (ticagrelor), a pan-selectin inhibitor (Bimosiamose), and a histamine receptor antagonist (Cimetidine). These compounds significantly decreased platelet adhesion to the damaged endothelium, highlighting that this model can successfully screen anti-platelet compounds that target platelets directly or the endothelium indirectly.

Development and validation of a nomogram for steroid-resistance prediction in immune thrombocytopenia patients

OBJECTIVES

Corticosteroid is first-line therapy in immune thrombocytopenia. However, nearly 30% of patients appear in steroid-resistance. Our research analyses the relevant indicators of patients and develops a risk prediction model to predict the poor response to steroid-therapy in ITP patients.

METHODS

We collected data from 111 ITP patients admitted to Xiamen University Zhongshan Hospital from 2013 to 2019 as the training cohort and 65 ITP patients during 2019-2020 as the external validation cohort. Screening significant factors(P < 0.05) in univariate analysis, and further identified to be independent variables in multivariable logistic regression analysis. Incorporated the significant risk factors in and presented them with a nomogram based on independent risk predictors. The nomogram was assessed by receiver operating characteristics curves and decision curve analysis.

RESULTS

We constructed a steroid-resistance prediction model based on the potential predictors including age, serum ferritin and expression of HBsAg. As a result, based on the area under the ROC curves, the training cohort (AUC: 0.718, 95% CI: 0.615-0.821) and the external validation cohort (AUC:0.799,95%CI:0.692-0.905), which displayed good discrimination. The decision curve showed that predicting the steroid-refractory risk in ITP patients using this nomogram with a range of the threshold probability between >16% and <70%. The nomogram appears good performance in predicting steroid-refractory ITP patients.

CONCLUSION

Prediction model shows that elder patients with a high level of ferritin and positive expression of HBsAg may appear a high possibility of steroid-resistance. For these patients, TPO-RAs can be considered to help patients to get better treatment effects and develop a better health-related quality of life.

Primary immune thrombocytopenia in very elderly patients: particularities in presentation and management: results from the prospective CARMEN-France Registry

Data about the presentation and the management of primary immune thrombocytopenia (ITP) in very elderly patients (VEPs; aged ≥80 years) are lacking. The aim of the present study was to describe ITP in this subgroup. The data source was the prospective CARMEN-France registry. Patients included between 2013 and 2018 were selected. ITP presentation and management in VEPs was compared to elderly patients (EPs; aged 65-79 years). We assessed factors associated with bleeding at ITP onset in VEPs. Of 541 patients, 184 were included: 87 in the VEP group and 97 in the EP group. The mean age was 85·7 years in the VEP group. Comorbidities were more frequent in the VEP group (67·4% vs. 47·9%). The median platelet count at ITP onset was similar but severe bleeding tended to be more frequent in VEPs (10·3% vs. 4·1%, P = 0·1) as well as mortality. Exposure to ITP drugs, response to first-line treatment, need of second-line treatment, evolution towards persistency, occurrence of bleeding, infection and thrombosis did not differ between groups. In VEPs, factors associated to bleeding were female sex [odds ratio (OR) 4·75, 95% confidence interval (CI) 1·31-17·32] and platelet count of <20 × 10⁹ /l (OR 10·05, 95% CI 4·83-67·39). Exposure to anticoagulants was strongly associated with severe bleeding (OR 7·61, 95% CI 1·77-32·83).

Consensus guidelines for the management of adult immune thrombocytopenia in Australia and New Zealand

Introduction

The absence of high quality evidence for basic clinical dilemmas in immune thrombocytopenic purpura (ITP) underlines the need for contemporary guidelines relevant to the local treatment context. ITP is diagnosed by exclusions, with a hallmark laboratory finding of isolated thrombocytopenia.

Main recommendations

Bleeding, family and medication histories and a review of historical investigations are required to gauge the bleeding risk and possible hereditary syndromes. Beyond the platelet count, the decision to treat is affected by individual bleeding risk, disease stage, side effects of treatment, concomitant medications, and patient preference. Treatment is aimed at achieving a platelet count > 20 × 10⁹/L, and avoidance of severe bleeding. Steroids are the standard first line treatment, with either 6‐week courses of tapering prednisone or repeated courses of high dose dexamethasone providing equivalent efficacy. Intravenous immunoglobulin can be used periprocedurally or as first line therapy in combination with steroids.

Changes in management as a result of this statement

There is no consensus on choice of second line treatments. Options with the most robust evidence include splenectomy, rituximab and thrombopoietin receptor agonists. Other therapies include azathioprine, mycophenolate mofetil, dapsone and vinca alkaloids. Given that up to one‐third of patients achieve a satisfactory haemostatic response, splenectomy should be delayed for at least 12 months if possible. In life‐threatening bleeding, we recommend platelet transfusions to achieve haemostasis, along with intravenous immunoglobulin and high dose steroids.

Comparative study between two bleeding grading systems of immune thrombocytopenia purpura

OBJECTIVE

To explore the relationship between platelet count and bleeding score in immune thrombocytopenia purpura (ITP) and compare the clinical practicability of two bleeding grading systems with adult patients with ITP.

METHODS

A total of 204 patients were retrospectively analyzed with the ITP bleeding scale (IBLS) and the ITP bleeding assessment tool (version 2016) (ITP-2016). The correlation between the two bleeding score systems and the relations among the platelet counts were respectively analyzed.

RESULTS

(1) There is a linear relationship between platelet count and bleeding score, no matter which scoring system it is based on (rs = -0.429, p < 0.001; rs = -0.331, p < 0.001, the analysis of the number of sites of Grade 1/2 bleeding were done; and rs = -0.466, p < 0.05, the analysis between platelet count and bleeding score by ITP-2016 respectively). (2) Platelet count and bleeding scores are negatively correlated in those with extremely low platelet counts ( < 10*10⁹/L). The number of sites of Grade 2 bleeding and the ITP-2016 scores are negatively correlated with platelet counts (rs = -0.15 and rs = -0.244, p < 0.05, respectively). Significantly, there is no correlation between the platelet count and bleeding scores when the platelet count is more than 10*10⁹/L. (3) It takes less time to score with ITP-2016 than IBLS (z = -3.825, P < 0.001).

CONCLUSIONS

There is good responsiveness, strong assessment consistency, close correlation between ITP-2016 and IBLS. ITP-2016 takes less time-consuming in clinical application. It can be used as an effective tool of condition judgement, risk assessment and efficacy evaluation of patients with ITP.

Diagnostic approach to the patient with a suspected inherited platelet disorder: Who and how to test

Bleeding and thrombocytopenia are common referrals to the pediatric and adult hematology practice. The differential diagnosis encompasses a wide spectrum of entities that vary in acuity, severity, and etiology. Most will be acquired (especially in adult patients), but many can be inherited, and some may have manifestations affecting other organ systems. The first step: defining whether the symptoms and/or laboratory findings are clinically significant and warrant additional work-up, can be equally as challenging as reaching the diagnosis itself. How much bleeding is too much to be considered normal? How low of a platelet count is too low? Once the decision has been made to pursue additional studies, considering the increasing number of laboratory tests available, the diagnostic process can be complex. In this article, we outline a general approach for the evaluation of patients in whom an inherited platelet disorder is being considered. We present two clinical vignettes as introduction to the diagnostic approach to inherited platelet disorders. We describe the rationale for the different types of tests that are clinically available, their limitations, and finally the challenges that are frequently encountered in the interpretation of results. We also intend to provide some guidance on the expected phenotype in terms of severity of bleeding and/or thrombocytopenia according to the etiology of the inherited disorder. Our goal is to provide the practicing hematologist with a practical framework that is clinically applicable in their daily practice.

Definition of a critical bleed in patients with immune thrombocytopenia: Communication from the ISTH SSC Subcommittee on Platelet Immunology

BACKGROUND

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by low platelet counts and increased risk of bleeding. In preparation for an upcoming guideline, the ITP Emergency Management Guideline Panel, including clinical experts in hematology, emergency medicine, research methodology, and patient representatives, identified the need for a standardized definition of a critical ITP bleed. The goal of the definition was to distinguish critical bleeds from bleeds that may not require urgent treatment, typically in the context of severe thrombocytopenia.

METHODS

The panel met in person and virtually to achieve consensus on the criteria for critical bleeding events among patients with ITP. Existing ITP bleeding scores and published definitions of major bleeds in patients receiving anticoagulation informed the definition of a critical ITP bleed. The Platelet Immunology Scientific Standardization Committee (SSC) of the International Society on Thrombosis and Haemostasis endorsed the definition.

RESULTS

A critical ITP bleed was defined as: (a) a bleed in a critical anatomical site including intracranial, intraspinal, intraocular, retroperitoneal, pericardial, or intramuscular with compartment syndrome; or (2) an ongoing bleed that results in hemodynamic instability or respiratory compromise.

CONCLUSION

The definition of a critical ITP bleed was developed by the ITP Emergency Management Guideline Panel and endorsed by the Platelet Immunology SSC. It incorporates both anatomic and physiologic risk and pertains to patients with confirmed or suspected ITP who typically have severe thrombocytopenia (platelet count below 20 × 109 /L).

Management of Adult Patients with Immune Thrombocytopenia (ITP): A Review on Current Guidance and Experience from Clinical Practice

Immune thrombocytopenia (ITP) is an autoimmune process resulting in increased destruction and inadequate production of platelets that can result in bleeding, fatigue, and reduced health-related quality of life. While treatment is not required for many patients with ITP, the occurrence of bleeding manifestations, severe thrombocytopenia, and requirement for invasive procedures are among the reasons necessitating initiation of therapy. Corticosteroids, intravenous immunoglobulin, and anti-RhD immune globulin are typical first-line and rescue treatments, but these agents typically do not result in a durable remission in adult patients. Most patients requiring treatment therefore require subsequent line therapies, such as thrombopoietin receptor agonists (TPO-RAs), rituximab, fostamatinib, splenectomy, or a number of other immunosuppressive agents. In this focused review, we discuss management of adult ITP in the acute and chronic settings.

Perioperative thrombocytopenia

PURPOSE OF REVIEW

In this review, we discuss recent developments and trends in the perioperative management of thrombocytopenia.

RECENT FINDINGS

Large contemporary data base studies show that preoperative thrombocytopenia is present in about 8% of asymptomatic patients, and is associated with increased risks for bleeding and 30-day mortality. Traditionally specific threshold platelet counts were recommended for specific procedures. However, the risk of bleeding may not correlate well with platelet counts and varies with platelet function depending on the underlying etiology. Evidence to support prophylactic platelet transfusion is limited and refractoriness to platelet transfusion is common. A number of options exist to optimize platelet counts prior to procedures, which include steroids, intravenous immunoglobulin, thrombopoietin receptor agonists, and monoclonal antibodies. In addition, intraoperative alternatives and adjuncts to transfusion should be considered. It appears reasonable to use prophylactic desmopressin and antifibrinolytic agents, whereas activated recombinant factor VII could be considered in severe bleeding. Other options include enhancing thrombin generation with prothrombin complex concentrate or increasing fibrinogen levels with fibrinogen concentrate or cryoprecipitate.

SUMMARY

Given the lack of good quality evidence, much research remains to be done. However, with a multidisciplinary multimodal perioperative strategy, the risk of bleeding can be decreased effectively.

How I treat primary ITP in adult patients who are unresponsive to or dependent on corticosteroid treatment

Approximately 80% of adult patients with immune thrombocytopenia (ITP) have treatment failure with corticosteroids or become dependent on them and require second-line therapy. Several new and effective therapies have been introduced during the past decade and our understanding of disease burden and its effect on quality of life has expanded. It is now recommended that splenectomy, the standard second-line therapy for decades, be delayed for at least 12 to 24 months, allowing for more patients to achieve remission on medical therapies before considering surgery. It is highly recommended that medical therapies be used that have abundant clinical trial evidence, such as the thrombopoietin receptor agonists (TPO-RAs) rituximab and fostamatinib. Unfortunately, there are no reliable biomarkers that help in treatment selection. These therapeutic medical options have variable efficacy, safety profiles, mechanisms of action, and modes of administration. This enables and mandates an individualized approach to treatment, where patient involvement, preferences and values have become central to the process of choosing the appropriate therapy. Both TPO-RAs and fostamatinib are maintenance therapies, whereas rituximab is given for a limited number of doses. Although the response is usually maintained while receiving a TPO-RA or fostamatinib therapy, half of rituximab responders will no longer respond 1 to 2 years after administration and require retreatment or other therapy.

Risk factors for skin, mucosal, and organ bleeding in adults with primary ITP: a nationwide study in Japan

Bleeding manifestations in primary immune thrombocytopenia (ITP) range from skin petechiae to life-threatening intracranial hemorrhage (ICH). However, the relation between these various bleeding manifestations and the platelet count in ITP remains poorly characterized. Using a nationwide database of patients with ITP during the years 2005 to 2014 (10 years) in Japan, we analyzed 19 415 adult patients newly diagnosed with ITP, including 222 with ICH. The frequency of skin purpura was 64.8%, and this increased linearly with thrombocytopenia without a specific platelet count threshold. In contrast, mucosal bleeding (epistaxis and gingival bleeding) and organ bleeding (melena, hematuria, and ICH) increased exponentially with thrombocytopenia at a platelet count threshold of 10 to 15 × 109/L. Age showed a much weaker correlation than platelet count with skin and mucosal bleeding. However, the incidence of organ bleeding increased exponentially above 60 years of age. Multivariate analysis showed that the presence of mucosal bleeding was a risk factor for occurrence of melena and hematuria but not for ICH. The frequency of ICH was 1.1% and risk factors for ICH were age ≥60 years (odds ratio [OR], 3.09; 95% confidence interval [CI], 2.13-4.47; P < .001), platelet count <10 × 109/L (OR, 2.96; 95% CI, 2.11-4.15; P < .001), and the presence of hematuria (OR, 1.56; 95% CI, 1.04-2.35; P = .033). The relation between ICH and platelet count varied with age. This large-scale analysis of risk factors for bleeding in ITP has revealed distinct characteristics of skin, mucosal, and organ bleeding in adult patients with newly diagnosed ITP, thus indicating those who are at a high risk of severe organ bleeding.

Identification of occult cerebral microbleeds in adults with immune thrombocytopenia

Management of symptoms and prevention of life-threatening hemorrhage in immune thrombocytopenia (ITP) must be balanced against adverse effects of therapies. Because current treatment guidelines based on platelet count are confounded by variable bleeding phenotypes, there is a need to identify new objective markers of disease severity for treatment stratification. In this cross-sectional prospective study of 49 patients with ITP and nadir platelet counts <30 × 109/L and 18 aged-matched healthy controls, we used susceptibility-weighted magnetic resonance imaging to detect cerebral microbleeds (CMBs) as a marker of occult hemorrhage. CMBs were detected using a semiautomated method and correlated with clinical metadata using multivariate regression analysis. No CMBs were detected in health controls. In contrast, lobar CMBs were identified in 43% (21 of 49) of patients with ITP; prevalence increased with decreasing nadir platelet count (0/4, ≥15 × 109/L; 2/9, 10-14 × 109/L; 4/11, 5-9 × 109/L; 15/25 <5 × 109/L) and was associated with longer disease duration (P = 7 × 10-6), lower nadir platelet count (P = .005), lower platelet count at time of neuroimaging (P = .029), and higher organ bleeding scores (P = .028). Mucosal and skin bleeding scores, number of previous treatments, age, and sex were not associated with CMBs. Occult cerebral microhemorrhage is common in patients with moderate to severe ITP. Strong associations with ITP duration may reflect CMB accrual over time or more refractory disease. Further longitudinal studies in children and adults will allow greater understanding of the natural history and clinical and prognostic significance of CMBs.

Insights on chronic immune thrombocytopenia pathogenesis: A bench to bedside update

Immune thrombocytopenia (ITP) is a heterogeneous disease with an unpredictable course. Chronicity can develop in up to two-thirds of adults and 20-25% of children, representing a significant burden on patients' quality of life. Despite acceptable responses to treatment, precise etiology and pathophysiology phenomena driving evolution to chronicity remain undefined. We analyzed reported risk factors for chronic ITP and associated them with proposed underlying mechanisms in its pathogenesis, including bone marrow (BM) microenvironment disturbances, clinical features, and immunological markers. Their understanding has diagnostic implications, such as screening for the presence of specific antibodies or BM examination employing molecular tools, which could help predict prognosis and recognize main pathogenic pathways in each patient. Identifying these underlying mechanisms could guide the use of personalized therapies such as all-trans retinoic acid, mTor inhibitors, FcRn inhibitors, oseltamivir, and others. Further research should lead to tailored treatments and chronic course prevention, improving patients' quality of life.

Primary Immune Thrombocytopenia: Novel Insights into Pathophysiology and Disease Management

Immune thrombocytopenia (ITP) is an autoimmune disorder defined by a significantly reduced number of platelets in blood circulation. Due to low levels of platelets, ITP is associated with frequent bruising and bleeding. Current evidence suggests that low platelet counts in ITP are the result of multiple factors, including impaired thrombopoiesis and variations in immune response leading to platelet destruction during pathological conditions. Patient outcomes as well as clinic presentation of the disease have largely been shown to be case-specific, hinting towards ITP rather being a group of clinical conditions sharing common symptoms. The most frequent characteristics include dysfunction in primary haemostasis and loss of immune tolerance towards platelet as well as megakaryocyte antigens. This heterogeneity in patient population and characteristics make it challenging for the clinicians to choose appropriate therapeutic regimen. Therefore, it is vital to understand the pathomechanisms behind the disease and to consider various factors including patient age, platelet count levels, co-morbidities and patient preferences before initiating therapy. This review summarizes recent developments in the pathophysiology of ITP and provides a comprehensive overview of current therapeutic strategies as well as potential future drugs for the management of ITP.

Risk factors and predictors of treatment responses and complications in immune thrombocytopenia

Management of adult patients with immune thrombocytopenia (ITP) is often unsatisfactory, due to variable efficacy of treatment, risk of life-threatening bleeding if disease control is poor, and side effects associated with treatment. Lack of data on the platelet count threshold associated with bleeding and infection risk associated with ITP treatment limits risk/benefit clinical decision making. We reviewed medical records of all ITP patients who were admitted to our hospital between 2012 and 2017 to evaluate the platelet count threshold for bleeding, infection burden associated with treatment, and real-world efficacy of second-line treatment. We demonstrated fair discrimination between platelet count and occurrence of bleeding, with 15 × 10⁹/L being the optimal cut-off for predicting any bleeding while 20 × 10⁹/L had the highest negative predictive value for severe bleeding. In multivariable analyses, patients who were treated with corticosteroids for at least 2 months were 5.3 times as likely to have an infection. In addition, rituximab response was strongly associated with response to frontline corticosteroids and infection was associated with older age ≥ 65 years and corticosteroid dependence. If corticosteroids are initiated, physicians should aim for the shortest duration of treatment before switching to effective second-line agents for hemostatic platelet counts.

Perioperative outcomes for benign hysterectomy among women with thrombocytopenia

OBJECTIVE

To determine whether mild or moderate thrombocytopenia is associated with postoperative complications after benign hysterectomy.

METHODS

A retrospective study of data from women who underwent benign hysterectomy included in the American College of Surgeons National Surgical Quality Improvement Project Database. The data were stratified by normal platelet count, mild thrombocytopenia (100-149 × 10³ platelets/µl), and moderate thrombocytopenia (50-99 × 10³ platelets/µl). Multivariable logistic regression was used to determine the relationship between mild or moderate thrombocytopenia and the main outcome measures.

RESULTS

Moderate thrombocytopenia was associated with an increased risk of perioperative transfusion (adjusted odds ratio [aOR], 2.87; 95% confidence interval [CI], 1.96-4.21) and reoperation (aOR, 4.03; 95% CI, 1.94-17.33), but mild thrombocytopenia was not. There was an increased risk of infection among women with both mild (aOR, 1.38; 95% CI, 1.12-1.69) and moderate (aOR, 2.00; 95% CI,1.23-3.22) thrombocytopenia. There was no association between either mild or moderate thrombocytopenia and readmission, prolonged hospital stay, or longer surgical time.

CONCLUSION

Thrombocytopenia was found to be associated with increased infectious morbidity after hysterectomy, and moderate thrombocytopenia was associated with an increased risk of perioperative transfusion and reoperation.

New Developments in the Pathophysiology and Management of Primary Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease that is characterized by a significant reduction in the number of circulating platelets and frequently associated with bleeding. Although the pathogenesis of ITP is still not completely elucidated, it is largely recognized that the low platelet count observed in ITP patients is due to multiple alterations of the immune system leading to increased platelet destruction as well as impaired thrombopoiesis. The clinical manifestations and patients' response to different treatments are very heterogeneous suggesting that ITP is a group of disorders sharing common characteristics, namely, loss of immune tolerance toward platelet (and megakaryocyte) antigens and dysfunctional primary hemostasis. Management of ITP is challenging and requires intensive communication between patients and caregivers. The decision to initiate treatment should be based on the platelet count level, age of the patient, bleeding manifestation, and other factors that influence the bleeding risk in individual patients. In this review, we present recent data on the mechanisms that lead to platelet destruction in ITP with a particular focus on current findings concerning alterations of thrombopoiesis. In addition, we give an insight into the efficacy and safety of current therapies and management of ITP bleeding emergencies.

New insights into the epidemiology of immune thrombocytopenia in adult patients: Impact for clinical practice

New insights into immune thrombocytopenia (ITP) epidemiology in adult patients highlight three main outcomes of morbidity and mortality: bleeding, infection and thrombosis. This review depicts current evidence about incidence and risk factors of bleeding, infection and thrombosis as well as predictors of chronicity, and shows how this assessment impacts the choice of ITP second-line treatment at the individual-level basis.

Risk stratification and outcomes of intracranial hemorrhage in patients with immune thrombocytopenia under 60 years of age

Intracranial hemorrhage (ICH) is a devastating complication of immune thrombocytopenia (ITP). However, information on ICH in ITP patients under the age of 60 years is limited, and no predictive tools are available in clinical practice. A total of 93 adult patients with ITP who developed ICH before 60 years of age were retrospectively identified from 2005 to 2019 by 27 centers in China. For each case, 2 controls matched by the time of ITP diagnosis and the duration of ITP were provided by the same center. Multivariate analysis identified head trauma (OR = 3.216, 95%CI 1.296-7.979, P =.012), a platelet count ≤ 15,000/μL at the time of ITP diagnosis (OR = 1.679, 95%CI 1.044-2.698, P =.032) and severe/life-threatening bleeding (severe bleeding vs. mild bleeding, OR = 1.910, 95%CI 1.088-3.353, P =.024; life-threatening bleeding vs. mild bleeding, OR = 2.620, 95%CI 1.360-5.051, P =.004) as independent risk factors for ICH. Intraparenchymal hemorrhage (OR = 5.191, 95%CI 1.717-15.692, P =.004) and a history of severe bleeding (OR = 4.322, 95%CI 1.532-12.198, P =.006) were associated with the 30-day outcome of ICH. These findings may facilitate ICH risk stratification and outcome prediction in patients with ITP.

Management of major bleeds in patients with immune thrombocytopenia

BACKGROUND

A standard approach to the recognition and management of major bleeding in immune thrombocytopenia (ITP) is lacking.

METHODS

Retrospective cohort study of ITP patients presenting to the emergency department (ED) with severe thrombocytopenia (platelet count <20 × 109 /L) and bleeding in four academic hospitals from 2008 to 2016. We defined a major ITP bleed as a bleed at a critical site or causing hemodynamic instability.

RESULTS

We identified 112 ITP patients (n = 141 visits) who presented to the ED with platelets <20 × 109 /L and bleeding. Twenty--nine patients (26%) had 32 ED visits with major bleeds. Risk factors for major bleeds were older age (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.06), male sex (OR 3.25, 95% CI 1.22-9.32), and more prior ITP therapies (OR 1.42, 95% CI 1.10-1.87). Acute treatment of major bleeds required a median of three treatments (interquartile range [IQR] 2--4), which included intravenous immune globulin (91% of visits), corticosteroids (78% of visits), and platelet transfusions (75% of visits). Three patients (10%) died, nine (31%) developed recurrent bleeds, one (3%) developed arterial thrombosis, and one (3%) had permanent neurological disability. Six patients presented with minor bleeding and subsequently developed a major bleed after a median of 2 days (IQR 1-3). All six patients had oral purpura and four of six had gross hematuria preceding the major bleed.

CONCLUSIONS

Major ITP bleeds are associated with significant morbidity and mortality. Oral purpura and hematuria often preceded major bleeds. Further research is needed to refine the definition of a major ITP bleed and develop evidence-based treatment strategies.