Platelets are among the most abundant cells in the body and play important roles in coagulation and immunity. Platelets are formed when hematopoietic stem cells proliferate and differentiate into megakaryocytes via the regulation of various cytokines. After the megakaryocytes mature in the bone marrow cavity, proplatelets are released into the blood circulation where they eventually remodel into mature platelets. Given that the production and functions of platelets involve the regulation of many factors-such as hematopoietic stem cells, the hematopoietic microenvironment, and cytokines-the causes and mechanisms of platelet-related diseases are diverse, often involving platelet production, clearance, and distribution. In this review, we examined the regulation of platelet production and summarized common disorders affecting platelet quantity, namely, thrombocytopenia and thrombocytosis. In addition, we reviewed previous clinical studies and summarized the medication strategies commonly used for the treatment of different platelet disorders in different clinical scenarios.

Objective Lusutrombopag is recommended for severe thrombocytopenia (<5.0×104/μL) in patients with chronic liver disease who are scheduled to undergo invasive procedures. However, reports on the efficacy of repeated lusutrombopag dosing are scarce. It is also not known whether lusutrombopag causes the platelet count to exceed 5.0×104/μL. We evaluated the efficacy of repeated lusutrombopag dosing and the efficacy of the platelet prediction simulation software program. Methods We evaluated the number of platelet elevations according to the number of lusutrombopag administrations. We also evaluated the correlation between the highest software-predicted platelet count and the platelet count measured in actual clinical practice. Patients This retrospective study included 236 patients treated with lusutrombopag at 11 medical institutions in Japan. Results The platelet count increased with the number of lusutrombopag administrations (1, 2, 3, 4, >4) in all groups, and no significant difference was found among the groups (p = 0.169). In all groups, the platelet counts reached their highest levels at 8-14 days after treatment with lusutrombopag (p = 0.243). There was a correlation between the highest software-predicted platelet count and the platelet count measured in actual clinical practice in all dose frequency groups; however, the correlation was the strongest in the one-dose group (r = 0.74, p <0.0001). Conclusion Frequent lusutrombopag administration is therefore both effective and safe, and a platelet prediction simulation software program is thus considered to be useful in practice.

Autoimmune liver diseases (AiLDs), including autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC), are immune-mediated conditions associated with significant hepatic and systemic manifestations. Among these, cytopenias-defined as reductions in blood cell counts affecting single or multiple lineages-represent a clinically important, though often under-recognized, complication. Cytopenias in AiLDs arise from diverse mechanisms, including immune-mediated destruction, hypersplenism due to portal hypertension, bone marrow suppression, and nutritional deficiencies. These abnormalities can exacerbate bleeding, infections, or fatigue, complicating the disease course and impacting therapeutic strategies. Immune-mediated cytopenias, such as autoimmune hemolytic anemia (AIHA), immune thrombocytopenic purpura (ITP), and autoimmune neutropenia (AIN), are more frequently associated with AIH, whereas cytopenias in PBC and PSC are largely attributed to hypersplenism. Diagnostic evaluation involves a systematic approach combining clinical history, laboratory testing (e.g., complete blood counts, Coombs tests, and nutritional assessments), imaging studies, and bone marrow evaluation in complex cases. Treatment strategies aim to address the underlying cause of cytopenias, including immunosuppressive therapy for autoimmune mechanisms, beta-blockers or splenectomy for hypersplenism, and supplementation for nutritional deficiencies. Challenges include distinguishing between immune- and hypersplenism-related cytopenias, managing drug-induced cytopenias, and optimizing care in transplant candidates. The recently recognized IgG4-related disease, often mimicking cholestatic AiLDs, adds another layer of complexity, given its association with autoimmune cytopenias and hypersplenism. This review aims to act as a guide for the clinician dealing with patients with AiLDs with respect to the occurrence of cytopenias, with a specific focus on pathophysiology and management of these cytopenias. Furthermore, there need to be enhanced multidisciplinary discussions about those patients between the hematologists and hepatologists, with a maintenance of a high index of suspicion for the rarer causes of cytopenias in AiLDs on the part of the treating physician, and there is a need for further studies to elucidate the mechanisms behind the occurrence of cytopenias in AiLDs.

Cancer therapy-induced thrombocytopenia (CT-IT) is one of the most common hematological toxicities of anti-cancer therapy, often leading to treatment dose reduced, postponed, or treatment plans altered or even discontinued. Thrombopoietin (TPO) is the only key regulatory factor in platelet production, and TPO receptor is considered an ideal target for the treatment of thrombocytopenia. Thrombopoietic agents, including recombinant human thrombopoietin (rhTPO) and thrombopoietin receptor agonists (TPO-RAs), bind to different regions of the TPO receptor, activating downstream signaling pathways to increase platelet levels. In recent years, numerous studies have demonstrated the effectiveness of thrombopoietic agents in the management of CT-IT. These agents can reduce bleeding risk, decrease platelet transfusions, and maintain relative dose intensity (RDI) of anti-cancer treatments. This article provides a review of the current progress in the application of thrombopoietic agents for CT-IT management.

Hepatopathy-related thrombocytopenia refers to a reduction in platelet count caused by liver disease or its treatment. The incidence of this condition is correlated with the duration and severity of liver disease. The direct impact of thrombocytopenia on the clinical outcome of patients with liver disease is an increased risk of bleeding. In addition, the indirect effect involves delays or discontinuation of treatment due to the potential risk of bleeding. The pathophysiological mechanisms of hepatopathy-related thrombocytopenia include reduced platelet production, abnormal distribution, increased destruction or consumption, and so on. Current treatment strategies targeting different mechanisms include thrombopoietic agents, surgery, immunosuppressants, and platelet transfusion. However, their clinical application lacks standardization. The National Clinical Research Center for Infectious Diseases organized experts to discuss and develop this consensus to enhance the clinical management level of hepatopathy-related thrombocytopenia in China. The experts focused on aspects of diagnosis, classification, and choosing the best treatment plans based on the most recent research in the field.

To determine the rate of platelet transfusion in patients with cirrhosis and severe thrombocytopenia (platelet counts <50 × 109/L) undergoing high-risk invasive procedures when prescribed by thromboelastography (TEG) compared with empirical and on-demand transfusion strategies.

This was a single-center, single-blinded, randomized controlled trial. Patients with cirrhosis and severe thrombocytopenia undergoing high-risk invasive procedures were randomized into 3 groups: TEG group, transfusions based on TEG parameters; standard of care (SOC) group, 3 units of random donor platelets before procedure; and on-demand group, transfusions based on procedural adverse events/clinician's discretion. The primary outcome was periprocedural platelet transfusion in each arm.

Eighty-seven patients were randomized (29 in each group) with no significant differences in demographics/coagulation profile/procedures. The median platelet count was 33 × 109/L (interquartile range, 26-43 × 109/L). Percutaneous liver biopsy was the most common procedure (46, 52.9%). Significantly lower number of patients in the TEG group received platelets (4 cases, 13.8%; 95% CI, 3.9-31.7) compared with SOC group (100%; 95% CI, 88.1-100; P < .001). Four patients in the on-demand group received platelets (13.8%; 95% CI, 3.9-31.7). Minor (World Health Organization [WHO] Grade 2) procedure-related bleeding occurred in 3 (10%; 95% CI, 2.2-27.4) patients in the TEG-guided transfusion group compared with 1 (3.4%; 95% CI, 0.1-17.8) patient each in the SOC and on-demand groups (P = .43), although the study was not powered for comparison of bleeding rates. No bleeding-related mortality was observed in any of the 3 groups.

TEG-prescribed transfusion reduced prophylactic transfusions in patients with cirrhosis and severe thrombocytopenia undergoing high-risk invasive procedures. The study was not powered for comparison of bleeding rates.

Eltrombopag (EPAG), a thrombopoietin receptor agonist, was approved for the treatment of severe aplastic anemia (SAA) combined with immunosuppressive therapy (IST). However, EPAG contains a typical biphenyl structure, which causes liver function damage.

Twenty patients with SAA who were intolerant or refractory to EPAG were enrolled in a multicenter prospective registry of the Chinese Eastern Collaboration Group of Anemia (ChiCTR2100045895) from October 2020 to June 2023.

Eight patients who were ineffective to EPAG, six with kidney impairment, and nine with abnormal liver function (two with concomitant liver and kidney impairment) were converted to avatrombopag (AVA) therapy with the median duration of AVA treatment was 6 (3-24) months. 17 cases (85%) achieved trilineage hematological response (HR): complete remission (CR) in 3 cases (15%), good partial remission (GPR) in 4 cases (20%), partial remission (PR) in 10 cases (50%), and no response (NR) in 3 cases (15%). The median time to response was 1.7 (0.5-6.9) months, with 16 cases (94%) achieving response within six months and 17 cases (100%) within 12 months. 9 cases (50%) achieved transfusion independence. AVA converted treatment was associated with higher neutrophil counts (0.8×109/L vs 2.2×109/L, p=0.0003), platelet counts (11×109/L vs 39×109/L, p=0.0008), hemoglobin count (59g/L vs 98g/L, p=0.0002), red cell count (1.06×1012/L vs 2.97×1012/L, p=0.001), and absolute reticulocyte count (31.99 ×109/L vs 67.05×109/L p=0.0004) were all significantly elevated compared with the pre-treatment level. After the conversion to AVA therapy, liver and kidney function indexes were maintained within the normal range, no AVA related grade 2 or higher adverse events occurred, and no thrombotic events occurred.

The conversion to AVA was an optimal choice for patients with SAA who were EPAG intolerant or refractory.

http://www.chictr.org.cn/showproj.html?proj=125480, identifier ChiCTR2100045895.

Background and aims: Management of severe thrombocytopenia poses significant challenges in patients with chronic liver disease. Here, we aimed to evaluate the first real-world European post-marketing cohort of cirrhotic patients treated with lusutrombopag, a thrombopoietin receptor agonist, verifying the efficacy and safety of the drug. Methods: In the REAl-world Lusutrombopag treatment in ITalY (REALITY) study, we collected data from consecutive cirrhotic patients treated with lusutrombopag in 19 Italian hepatology centers, mostly joined to the "Club Epatologi Ospedalieri" (CLEO). Primary and secondary efficacy endpoints were the ability of lusutrombopag to avoid platelet transfusions and to raise the platelet count to ≥50,000/μL, respectively. Treatment-associated adverse events were also collected. Results: A total of 66 patients and 73 cycles of treatment were included in the study, since 5 patients received multiple doses of lusutrombopag over time for different invasive procedures. Fourteen patients (19%) had a history of portal vein thrombosis (PVT). Lusutrombopag determined a significant increase in platelet count [from 37,000 (33,000-44,000/μL) to 58,000 (49,000-82,000), p < 0.001]. The primary endpoint was met in 84% of patients and the secondary endpoint in 74% of patients. Baseline platelet count was the only independent factor associated with response in multivariate logistic regression analysis (OR for any 1000 uL of 1.13, CI95% 1.04-1.26, p 0.01), with a good discrimination power (AUROC: 0.78). Notably, a baseline platelet count ≤ 29,000/μL was identified as the threshold for identifying patients unlikely to respond to the drug (sensitivity of 91%). Finally, de novo PVT was observed in four patients (5%), none of whom had undergone repeated treatment, and no other safety or hemorrhagic events were recorded in the entire population analyzed. Conclusions: In this first European real-world series, lusutrombopag demonstrated efficacy and safety consistent with the results of registrational studies. According to our results, patients with baseline platelet counts ≤29,000/μL are unlikely to respond to the drug.

Partial splenic embolization (PSE) has been proposed to treat the consequences of hypersplenism in the context of portal hypertension, especially thrombocytopenia. However, a high morbidity/mortality rate has made this technique unpopular. We conducted a multicenter retrospective nationwide French study to reevaluate efficacy and tolerance.

All consecutive patients who underwent PSE for hypersplenism and portal hypertension in 7 tertiary liver centers between 1998 and 2023 were included.

The study population consisted of 91 procedures in 90 patients, with a median age of 55.5 years [range 18-83]. The main cause of portal hypertension was cirrhosis (84.6 %). The main indications for PSE were (1) an indication of medical treatment or radiological/surgical procedure in the context a severe thrombocytopenia (59.3 %), (2) a chronic hemorrhagic disorder associated with a severe thrombocytopenia (18.7 %), and (3) a chronic pain associated with a major splenomegaly (9.9 %). PSE was associated with a transjugular intrahepatic portosystemic shunt in 20 cases. Median follow-up after PSE was 41.9 months [0.5-270.5]. Platelet count increased from a median of 48.0 G/L [IQR 37.0; 60.0] to 100.0 G/L [75.0; 148]. Forty-eight patients (52.7 %) had complications after PSE; 25 cases were considered severe (including 7 deaths). A Child-Pugh B-C score (p < 0.02) was significantly associated with all complications, a history of portal vein thrombosis (p < 0.01), and the absence of prophylactic antibiotherapy (p < 0.05) with severe complications.

Our results strongly confirm that PSE is very effective, for a long time, although a quarter of the patients experienced severe complications. Improved patient selection (exclusion of patients with portal vein thrombosis and decompensated cirrhosis) and systematic prophylactic antibiotherapy could reduce morbidity and early mortality in the future.

Immune thrombocytopenia (ITP) management with co-existing acute coronary syndrome (ACS) remains challenging as it requires a clinically relevant balance between the risk and outcomes of thrombosis and the risk of bleeding. However, the literature evaluating the treatment approaches in this high-risk population is scarce.

In this review, we aimed to summarize the available literature on the safety of ITP first- and second-line therapies to provide a practical guide on the management of ITP co-existing with ACS. We recommend holding antithrombotic therapy, including antiplatelet agents and anticoagulation, in severe thrombocytopenia with a platelet count < 30 × 109/L and using a single antiplatelet agent when the platelet count falls between 30 and 50 × 109/L. We provide a stepwise approach according to platelet count and response to initial therapy, starting with corticosteroids, with or without intravenous immunoglobulin (IVIG) with a dose limit of 35 g, followed by thrombopoietin receptor agonists (TPO-RAs) to a target platelet count of 200 × 109/L and then rituximab.

Our review may serve as a practical guide for clinicians in the management of ITP co-existing with ACS.

Patients with cirrhosis develop complex alterations in primary hemostasis that include both hypocoagulable and hypercoagulable features. This includes thrombocytopenia, multiple alterations of platelet function, and increased plasma levels of von Willebrand factor. Contrary to the historical view that platelet dysfunction in cirrhosis might be responsible for an increased bleeding tendency, the current theory posits a rebalanced hemostasis in patients with cirrhosis. Severe thrombocytopenia is not indicative of the bleeding risk in patients undergoing invasive procedures and does not dictate per se the need for pre-procedural prophylaxis. A more comprehensive and individualized risk assessment should combine hemostatic impairment, the severity of decompensation and systemic inflammation, and the presence of additional factors that may impair platelet function, such as acute kidney injury and bacterial infections. Although there are multiple, complex alterations of platelet function in cirrhosis, their net effect is not yet fully understood. More investigations evaluating the association between alterations of platelet function and bleeding/thrombosis may improve risk stratification in patients with decompensated cirrhosis. Besides hemostasis, the assessment of von Willebrand factor Ag and ADP-induced, whole-blood platelet aggregation normalized by platelet count (VITRO score and PLT ratio) are promising biomarkers to predict the risk of hepatic decompensation and survival in both compensated and decompensated patients. Further investigations into the in vivo interplay between platelets, circulating blood elements, and endothelial cells may help advance our understanding of cirrhotic coagulopathy. Here, we review the complex changes in platelets and primary hemostasis in cirrhosis and their potential clinical implications.

Chemotherapy-induced thrombocytopenia (CIT) is a common complication of antineoplastic therapy, resulting in antineoplastic therapy dose reductions, treatment delays, treatment discontinuation, and morbid bleeding events. Despite several decades of research into thrombopoietic growth factors in CIT, there are presently no available U.S. FDA- or EMA-approved agents to treat CIT. However, a respectable body of evidence has been published evaluating the thrombopoietin receptor agonists (TPO-RAs) for the management and prevention of CIT in patients with solid tumors, and critical studies are ongoing with the TPO-RAs romiplostim and avatrombopag. When employed in the appropriate patient population and used properly, TPO-RAs can successfully and safely manage CIT for extended periods of time with minimal apparent risks. This comprehensive review discusses the evidence for TPO-RAs in CIT in patients with solid tumors, provides detailed guidance for their use in the clinic, and discusses ongoing essential clinical trials in management of CIT.

Patients with advanced chronic liver disease (CLD) often need procedures to both treat and prevent complications of portal hypertension such as ascites or gastrointestinal bleeding. Abnormal results for hemostatic tests, such as prolonged prothrombin time, international normalized ratio, and/or thrombocytopenia, are commonly encountered, raising concerns about increased bleeding risk and leading to transfusion to attempt to correct prior to interventions. However hemostatic markers are poor predictors of bleeding risk in CLD, and routine correction, particularly with fresh frozen plasma and routine platelet transfusions, should be avoided. This narrative review discusses the hemostatic management of patients with CLD using 2 case descriptions.

Early stages of hepatitis B virus (HBV) infection usually involve inflammation of the liver. Patients with chronic infection have an increased risk of progressive liver fibrosis, cirrhosis, and life-threatening clinical complications of end-stage hepatocellular carcinoma (HCC).

Early diagnosis of hepatic fibrosis and timely clinical management are critical to controlling disease progression and decreasing the burden of end-stage liver cancer. Fibrosis staging, through its current gold standard, liver biopsy, improves patient outcomes, but the clinical procedure is invasive with unpleasant post-procedural complications. Routine blood test markers offer promising diagnostic potential for early detection of liver disease without biopsy. There is a plethora of candidate routine blood test markers that have gone through phases of biomarker validation and have shown great promise, but their current limitations include a predictive ability that is limited to only a few stages of fibrosis. However, the advent of machine learning, notably pattern recognition, presents an opportunity to refine blood-based non-invasive models of hepatic fibrosis in the future.

In this review, we highlight the current landscape of routine blood-based non-invasive models of hepatic fibrosis, and appraise the potential application of machine learning (pattern recognition) algorithms to refining these models and optimising clinical predictions of HBV-associated liver disease.

Machine learning via pattern recognition algorithms takes data analytics to a new realm, and offers the opportunity for enhanced multi-marker fibrosis stage prediction using pathology profile that leverages information across patient routine blood tests.

The phase 4 observational cohort study assessed the effectiveness and safety of the thrombopoietin receptor agonist avatrombopag in patients with chronic liver disease (CLD) and thrombocytopenia undergoing a procedure. Patients with CLD may have thrombocytopenia, increasing the risk of periprocedural bleeding. Prophylactic platelet transfusions used to reduce this risk have limitations including lack of efficacy and transfusion-associated reactions. Prophylactic thrombopoietin receptor agonists have been shown to increase platelet counts and decrease platelet transfusions. Effectiveness was assessed by change from baseline in platelet count and proportion of patients needing a platelet transfusion. Safety was assessed by monitoring adverse events (AEs). Of 50 patients enrolled, 48 were unique patients and 2 patients were enrolled twice for separate procedures. The mean (standard deviation) change in platelet count from baseline to procedure day was 41.1 × 109/L (33.29 × 109/L, n = 38), returning to near baseline at the post-procedure visit (change from baseline -1.9 × 109/L [15.03 × 109/L], n = 11). The proportion of patients not requiring a platelet transfusion after baseline and up to 7 days following the procedure was 98% (n = 49). Serious AEs were infrequent (n = 2 [4%]). No treatment-emergent AEs were considered related to avatrombopag. There were 2 mild bleeding events, no thromboembolic events or deaths, and no patients received rescue procedures (excluding transfusions). This study found that in a real-world setting, treatment with avatrombopag was well tolerated, increased the mean platelet count by procedure day, and reduced the need for intraoperative platelet transfusions in patients with CLD and thrombocytopenia.

Advanced chronic liver disease is accompanied with relevant changes in the corpuscular and plasmatic coagulation system. Due to thrombocytopenia that is regularly observed in these patients, platelet transfusions are often performed prior invasive procedures to prevent possible bleeding complications. However, platelet transfusions are associated with clinically significant adverse events and economically relevant health care costs. Thus, avoiding unnecessary platelet transfusions remains pivotal in daily clinical practice. The first step is to carefully check if increasing platelet counts prior to a planned invasive procedure is really necessary. Nowadays, two well-tolerated thrombopoetin-receptor agonists (TPO-RAs), Avatrombopaq and Lusutrombopaq, to treat thrombocytopenia preemptively before an invasive procedure in patients with liver cirrhosis are available. This review provides a guide for clinician when to increase platelet counts prior an invasive procedure in patients with liver cirrhosis and helps to identify situations in which the use of TPO-RA may be reasonable.

There are not many publications that provide a holistic view of the management of primary and secondary ITP as a whole, reflecting the similarities and differences between the two. Given the lack of major clinical trials, we believe that comprehensive reviews are much needed to guide the diagnosis and treatment of ITP today. Therefore, our review addresses the contemporary diagnosis and treatment of ITP in adult patients. With respect to primary ITP we especially focus on establishing the management of ITP based on the different and successive lines of treatment. Life-threatening situations, "bridge therapy" to surgery or invasive procedures and refractory ITP are also comprehensively reviewed here. Secondary ITP is studied according to its pathogenesis by establishing three major differential groups: Immune Thrombocytopenia due to Central Defects, Immune Thrombocytopenia due to Blocked Differentiation and Immune Thrombocytopenia due to Defective Peripheral Immune Response. Here we provide an up-to-date snapshot of the current diagnosis and treatment of ITP, including a special interest in addressing rare causes of this disease in our daily clinical practice. The target population of this review is adult patients only and the target audience is medical professionals.

Patients with JAK2V617F-positive myeloproliferative neoplasms (MPNs) and clonal hematopoiesis of indeterminate potential (CHIP) are at a significantly higher risk of cardiovascular diseases (CVDs). Endothelial cells (ECs) carrying the JAK2V617F mutation can be detected in many MPN patients. Here, we investigated the impact of endothelial JAK2V617F mutation on CVD development using both transgenic murine models and human induced pluripotent stem cell lines. Our findings revealed that JAK2V617F mutant ECs promote CVDs by impairing endothelial function and undergoing endothelial-to-mesenchymal transition (EndMT). Importantly, we found that inhibiting the endothelial thrombopoietin receptor MPL suppressed JAK2V617F-induced EndMT and prevented cardiovascular dysfunction caused by mutant ECs. These findings propose that targeting the endothelial MPL receptor could be a promising therapeutic approach to manage CVD complications in patients with JAK2V617F-positive MPNs and CHIP. Further investigations into the impact of other CHIP-associated mutations on endothelial dysfunction are needed to improve risk stratification for individuals with CHIP.

Liver cirrhosis remains a major public health issue. Liver fibrosis leading to cirrhosis is the terminal stage of various chronic liver diseases. Inflammatory cytokines are involved in the pathogenesis. Patients with cirrhosis often have hematological abnormalities, such as anemia and thrombocytopenia, which have multifactorial etiologies. Anemia in cirrhosis could be related to bleeding leading to iron deficiency anemia or other nutritional anemia such as vitamin B12 and folate deficiency. The pathophysiology of thrombocytopenia in liver cirrhosis has been postulated to range from splenic sequestration to bone marrow suppression from toxic agents, such as alcohol. It often complicates management due to the risk of bleeding with severely low platelets. This review aimed to highlight pathogenesis of liver cirrhosis, hematological abnormalities in liver cirrhosis, and their clinical significance.

There are currently three thrombopoietin receptor agonists (TPO-RAs) approved in Europe for treating patients with immune thrombocytopenia (ITP): romiplostim (Nplate®), eltrombopag (Revolade®), and avatrombopag (Doptelet®). However, comparative clinical data between these TPO-RAs are limited. Therefore, the purpose of this study was to perform a literature review and seek expert opinion on the relevance and strength of the evidence concerning the use of TPO-RAs in adults with ITP. A systematic search was conducted in PubMed and Embase within the last 10 years and until June 20, 2022. A total of 478 unique articles were retrieved and reviewed for relevance. The expert consensus panel comprised ITP senior hematologists from eight countries across Central Europe. The modified Delphi method, consisting of two survey rounds, a teleconference and email correspondence, was used to reach consensus. Forty articles met the relevancy criteria and are included as supporting evidence, including five meta-analyses analyzing all three European-licensed TPO-RAs and comprising a total of 31 unique randomized controlled trials (RCTs). Consensus was reached on seven statements for the second-line use of TPO-RAs in the management of adult ITP patients. In addition, the expert panel discussed TPO-RA treatment in chronic ITP patients with mild/moderate COVID-19 and ITP patients in the first-line setting but failed to reach consensus. This work will facilitate informed decision-making for healthcare providers treating adult ITP patients with TPO-RAs. However, further studies are needed on the use of TPO-RAs in the first-line setting and specific patient populations.

Abnormal bleeding in patients with liver disease may result from elevated portal pressure and varix formation, reduced hepatic synthesis of coagulation proteins, qualitative platelet dysfunction, and/or thrombocytopenia. Major mechanisms of thrombocytopenia in liver disease include splenic sequestration and impaired platelet production due to reduced thrombopoietin production. Alcohol and certain viruses may induce marrow suppression. Immune thrombocytopenia (ITP) may co-occur in patients with liver disease, particularly those with autoimmune liver disease or chronic hepatitis C. Drugs used for the treatment of liver disease or its complications, such as interferon, immunosuppressants, and antibiotics, may cause thrombocytopenia. Periprocedural management of thrombocytopenia of liver disease depends on both individual patient characteristics and the bleeding risk of the procedure. Patients with a platelet count higher than or equal to 50 000/µL and those requiring low-risk procedures rarely require platelet-directed therapy. For those with a platelet count below 50 000/µL who require a high-risk procedure, platelet-directed therapy should be considered, especially if the patient has other risk factors for bleeding, such as abnormal bleeding with past hemostatic challenges. We often target a platelet count higher than or equal to 50 000/µL in such patients. If the procedure is elective, we prefer treatment with a thrombopoietin receptor agonist; if it is urgent, we use platelet transfusion. In high-risk patients who have an inadequate response to or are otherwise unable to receive these therapies, other strategies may be considered, such as a trial of empiric ITP therapy, spleen-directed therapy, or transjugular intrahepatic portosystemic shunt placement.

Patients with cirrhosis are at risk of both thrombotic and hemorrhagic events. Traditional hemostatic tests are inadequate to assess the complex and fragile balance of hemostasis in this setting, especially in advanced stages of disease such as decompensated cirrhosis or acute on chronic liver failure (ACLF). Furthermore, the indiscriminate use of pro-hemostatic agents for prophylaxis and treatment of bleeding episodes is still debated and often contraindicated. Alongside, splanchnic, and peripheral thrombotic events are frequent in this population and require management that involves a careful balance between risks and benefits of antithrombotic therapy.

This review aims to address the state of the art on the clinical management of the hemostatic balance of cirrhosis in terms of established knowledge and future challenges.

The old paradigm of cirrhosis as a naturally anticoagulated condition has been challenged by more sophisticated global tests of hemostasis. Integrating this information in the clinical decision-making is still challenging for physicians and experts in hemostasis.

Patients with myelofibrosis (MF) frequently develop thrombocytopenia as a consequence of bone marrow fibrosis, splenic sequestration, and myelosuppression from an inflammatory microenvironmental milieu. Thrombocytopenia occurs frequently at diagnosis, worsens with disease progression, is an independent adverse prognostic factor, and limits effective dosing of JAK2 inhibitors. Recently, pacritinib was approved for patients with MF and extreme thrombocytopenia. However, this JAK2/IRAK1 inhibitor is not primarily used to attain improvement in platelet count. In this narrative review, we discuss strategies to specifically address thrombocytopenia in MF patients including immunomodulatory drugs, synthetic androgens, hypomethylating agents and splenectomy, all of which have only modest efficacy in alleviating thrombocytopenia. We also detail transfusion approaches, including diagnostic and therapeutic consideration for platelet transfusion refractoriness. We end by discussing novel therapies, including TGFβ traps and recombinant pentraxin-2, which may increase platelet counts in MF patients. Despite recent therapeutic advancements in MF, there remains a near paucity of agents that can effectively alleviate thrombocytopenia.

Chronic liver disease (CLD) related thrombocytopenia increases the risk of bleeding and poor prognosis. Many liver disease patients require invasive procedures or surgeries, such as liver biopsy or endoscopic variceal ligation, and most of them have lower platelet counts, which could aggravate the risk of bleeding due to liver dysfunction and coagulation disorders. Unfortunately, there is no defined treatment modality for CLD-induced thrombocytopenia. Recombinant human thrombopoietin (rhTPO) is commonly used to treat primary immune thrombocytopenic purpura and thrombocytopenia caused by solid tumor chemotherapy; however, there are few reports on the use of rhTPO in the treatment of CLD-related thrombocytopenia.

To evaluate the efficacy of rhTPO in the treatment of patients with CLD-associated thrombocytopenia undergoing invasive procedures.

All analyses were based on the retrospective collection of clinical data of patients with CLD who were treated in the Department of Infectious Diseases at The First Affiliated Hospital of Soochow University between June 2020 and December 2021. Fifty-nine male and 41 female patients with liver disease were enrolled in this study to assess the changes in platelet counts and parameters before and after the use of rhTPO for thrombocytopenia. Adverse events related to treatment, such as bleeding, thrombosis, and disseminated intravascular coagulation, were also investigated.

Among the enrolled patients, 78 (78%) showed a platelet count increase after rhTPO use, while 22 (22%) showed no significant change in platelet count. The mean platelet count after rhTPO treatment in all patients was 101.53 ± 81.81 × 109/L, which was significantly improved compared to that at baseline (42.88 ± 16.72 × 109/L), and this difference was statistically significant (P < 0.001). In addition, patients were further divided into three subgroups according to their baseline platelet counts (< 30 × 109/L, 30-50 × 109/L, > 50 × 109/L). Subgroup analyses showed that the median platelet counts after treatment were significantly higher (P < 0.001, all). Ninety (90%) patients did not require platelet transfusion partially due to an increase in platelet count after treatment with rhTPO. No serious adverse events related to rhTPO treatment were observed. Overall, rhTPO demonstrated good clinical efficacy for treating CLD-associated thrombocytopenia.

rhTPO can improve platelet count, reduce the risk of bleeding, and decrease the platelet transfusion rate, which may promote the safety of invasive procedures and improve overall survival of patients with CLD.

Blood transfusion, splenectomy, and partial splenic embolization (PSE) are generally performed for thrombocytopenia in patients with cirrhosis. Recently, thrombopoietin (TPO) agonists have become available, and investigations of patients who would benefit from them are necessary. Therefore, it is important to understand the fluctuations in cytokine levels associated with PSE. Therefore, fluctuations in platelet-associated immunoglobulin G (PAIgG), interleukin 6 (IL-6), and TPO levels with PSE were analyzed in this study. The study included 110 patients with liver cirrhosis and thrombocytopenia, with the aim of improving platelet counts. Fluctuations in PAIgG, IL-6, and TPO levels were investigated. The average splenic embolization ratio was 58.0% in patients with PSE. The platelet count rose significantly from 6.95 [5.40, 8.60] × 104/mL to 14.05 [10.43, 18.05] × 104/mL (P < .01), IL-6 rose significantly from 3.56 [2.53, 7.33] pg/mL to 18.90 [9.17, 32.95] pg/mL (P < .01), TPO rose significantly from 0.82 [0.52, 1.21] fmol/mL to 1.58 [0.97, 2.26] fmol/mL (P < .01), and PAIgG decreased significantly from 64.20 [38.33, 118.75] ng/107 cells to 37.50 [22.25, 70.00] ng/107 cells (P < .01). On multivariate analysis of factors related to the rate of platelet increase with PSE, primary biliary cholangitis (B = 0.475, P < .01), splenic embolization ratio (B = 0.75, P < .01), IL-6 change ratio (B = 0.019, P < .01), and PAIgG change ratio (B = -0.325, P < .01) were significant. When attempting to improve thrombocytopenia with PSE, adequate splenic embolization needs to be obtained together with improvements in IL-6, PAIgG, and TPO levels. With unsatisfactory improvement in thrombocytopenia, TPO agonist administration was considered.

Lusutrombopag is an oral thrombopoietin receptor agonist (TPO-RA). Clinical trials have shown lusutrombopag's efficacy in reducing need for preoperative platelet transfusion in patients with chronic liver disease (CLD) and severe thrombocytopenia. This analysis assessed efficacy and safety of lusutrombopag in patients with severe thrombocytopenia and CLD undergoing planned invasive procedures.

An electronic database search (through 1 December 2020) identified three randomised, placebo-controlled, double-blind clinical trials comparing lusutrombopag with placebo in patients with CLD and platelet count below 50 × 109/L scheduled to undergo a procedure with a perioperative bleeding risk. A random-effects meta-analysis examined treatment effect, with Cochrane Collaboration's tool assessing risk of bias.

The meta-analysis included 343 (lusutrombopag 3 mg, n = 173; placebo, n = 170) patients. More patients met the criteria for treatment response (platelet count at least 50 × 109/L and increase of at least 20 × 109/L from baseline anytime during the study) with lusutrombopag versus placebo (risk ratio [RR] 6.39; 95% confidence interval [CI] 3.69, 11.07; p < 0.0001). The primary efficacy outcome, proportion of patients requiring no platelet transfusion and no rescue therapy for bleeding for at least 7 days post procedure, was achieved by more patients treated with lusutrombopag versus placebo (RR 3.42; 95% CI 1.86, 6.26; p = 0.0001). The risk of any bleeding event was significantly lower with lusutrombopag compared to placebo (RR 0.55; 95% CI 0.32, 0.95; p = 0.03); conversely, thrombosis event rates were similar between lusutrombopag and placebo (RR 0.79; 95% CI 0.19, 3.24; p = 0.74).

This meta-analysis showed that treatment of severe thrombocytopenia with lusutrombopag in patients with CLD prior to a planned invasive procedure was efficacious and safe in increasing platelet counts, avoiding the need for platelet transfusions, and reducing risk of bleeding, thereby enhancing the certainty of evidence supporting the efficacy and safety of lusutrombopag.

Our understanding of nonalcoholic steatohepatitis (NASH) pathophysiology continues to advance rapidly. Given the complexity of the pathogenesis of NASH, the field has moved from describing the single pathogenesis of NASH to deeply phenotyping with a description of the multi-mechanism and multi-target pathogenesis that includes glucose, lipid and cholesterol metabolism, fibrotic progression, inflammation, immune reaction and apoptosis. To make the picture more complex, the pathogenesis of NASH involves pathological connections between the liver and several organs such as the adipose, pancreas, kidney and gut. Numerous pharmacologic candidates have been tested in clinical trials and have generated some positive results. Importantly, PPAR as triglyceride synthesis inhibitor and FXR as bile acids synthesis inhibitor have displayed beneficial effects on candidates for lipid and cholesterol metabolism. Although the efficacy of these drugs has been affirmed, serious side effects hinder their further development. It is a particularly important task to carry out the in-depth long-term research. Additionally, drug combination increases response rate and reduces side effects of a single drug. Mastering the advantages and limitations of clinical candidate drugs and continuous improvement and innovation are necessary to formulate a new strategy for the future treatment of NASH.

Chronic liver disease is characterized by several hematological derangements resulting in a complex and barely rebalanced haemostatic environment. Thrombocytopenia is the most common abnormality observed in these patients and recent advances have led to researchers focus the attention on the multifactorial origin of thrombocytopenia and on the key role of thrombopoietin (TPO) in its physiopathology. Severe thrombocytopenia (platelet count < 50000/μL) complicates the management of patients with chronic liver disease by increasing the potential risk of bleeding for invasive procedures, which may be therefore delayed or canceled even if lifesaving. In the very last years, the development of new drugs which exceed the limits of the current standard of care (platelet transfusions, either immediately before or during the procedure) paves the way to a new scenario in the management of this population of patients. Novel agents, such as the TPO-receptor agonists avatrombopag and lusutrombopag, have been developed in order to increase platelet production as an alternative to platelet transfusions. These agents have demonstrated a good profile in terms of efficacy and safety and will hopefully allow reducing limitations and risks associated with platelet transfusion, without any delay in scheduled interventions. Altogether, it is expected that patients with chronic liver disease will be able to face invasive procedures with one more string in their bow.

Multiple agents are available for the management of chronic immune thrombocytopenia (ITP), including thrombopoietin-receptor agonists (TPO-RAs), rituximab, and fostamatinib. Although TPO-RAs are often selected as treatments for chronic ITP, when choosing between the TPO-RAs, clinicians must balance safety profile, dosing restrictions, and method of administration incorporating patient preference.

We provide an overview of the thrombopoietin receptor agonists with a particular focus on avatrombopag, the newest agent in this class. In phase II and III clinical trials, avatrombopag was shown to offer durable improvement in platelet counts. We also include recent real-world evidence describing avatrombopag effectiveness in patients with poor response to prior treatments (including other TPO-RAs).

Compared with other TPO-RAs used to treat ITP, avatrombopag offers practical oral dosing with a single pill strength, does not require long-term dietary restrictions, and has no warning for hepatotoxicity. It is frequently effective after use of other TPO-RAs in ITP. The primary downside with avatrombopag use at present is the lack of longer-term safety data in ITP that presently exists for romiplostim and eltrombopag.

Patients with hepatitis B-related cirrhosis complicated with thrombocytopenia have a higher risk of bleeding, which may lead to higher mortality. We aimed to explore the efficacy and safety of recombinant human thrombopoietin (rhTPO) in the treatment of hepatitis B-related cirrhosis complicated with severe thrombocytopenia. Patients with hepatitis B-related compensated liver cirrhosis complicated with severe thrombocytopenia were divided into four groups according to the treatment method for thrombocytopenia. Platelet counts, the appearance of bleeding symptoms and adverse events were evaluated during the observation period. Also during the observational period, the platelet counts in the prednisone group, rhTPO group and prednisone plus rhTPO group were higher than those in the no treatment group. Patients without splenomegaly reacted better to rhTPO. Fewer bleeding events of grade 2 or worse were observed in the three treatment groups compared to the no treatment group. The platelet counts at baseline and treatment with rhTPO and/or prednisone were factors associated with bleeding events of grade 2 or worse in multivariate analysis. There could be a potential advantage for the use of rhTPO plus prednisone based on higher platelet counts and fewer bleeding events. Treatment with rhTPO was more effective in patients without splenomegaly.

Avatrombopag, a thrombopoietin receptor agonist, can reduce the need for platelet transfusions or rescue interventions for bleeding in patients with chronic liver disease (CLD) and thrombocytopenia undergoing scheduled procedures. A model analysis indicated that the effect of avatrombopag on platelet production was reduced in East Asian versus non-East Asian patients; however, the difference was deemed not clinically significant. Furthermore, a subgroup analysis of pooled Phase 3 trials showed similar avatrombopag efficacy across racial subgroups. The aim of this Phase 2 study was to corroborate the efficacy and safety of avatrombopag in Japanese patients with thrombocytopenia due to CLD.

Japanese patients with CLD and thrombocytopenia were randomized to receive placebo or avatrombopag 20, 40, or 60 mg daily for 5 days. The primary endpoint was responder rate in platelet counts at Visit 4 (10-13 days after treatment initiation), defined as the proportion of patients with platelet count ≥50 × 10⁹ /L and ≥20 × 10⁹ /L increase from baseline.

Thirty-nine patients were randomized and completed the study (placebo, n = 11; avatrombopag 20 mg, n = 7; 40 mg, n = 11; 60 mg, n = 10). Avatrombopag treatment was associated with significant increases in responder rate at Visit 4 in the 40 mg (63.6%; p = 0.004) and 60 mg (40%; p = 0.024) groups versus placebo (9.1%). Avatrombopag was well tolerated and no new safety signals were detected.

Efficacy and safety results from this study were consistent with previous studies in patients with CLD and thrombocytopenia undergoing elective procedures, supporting treatment with avatrombopag in the Japanese population.

gov identifier: NCT02227693.

Liver fibrosis results from an imbalance between extracellular matrix formation and degradation. The background of liver fibrosis is chronic inflammation and subsequent microcirculation disturbance including microthrombosis. Platelets actively participate in liver fibrosis not only as a part of the clotting system but also by releasing granules containing important mediators. In fact, platelets may play a dual role in the pathophysiology of liver fibrosis as they are able to stimulate regeneration as well as aggravate the destruction of the liver. Recent studies revealed that antiplatelet therapy correlates with inhibition of liver fibrosis. However, liver impairment is associated with extensive coagulation disorders thus the safety of antiplatelet therapy is an area for detailed exploration. In this review, the role of platelets in liver fibrosis and accompanying hemostatic disorders are discussed. Additionally, results of animal and human studies on antiplatelet drugs in liver disorders and their potential therapeutic utility are presented.

Management of coagulopathy in patients with advanced liver disease undergoing therapeutic endoscopic procedures is complex. Improvements in the understanding of hemostasis at a physiologic level have highlighted the inaccuracy of currently available clinical tests, like platelet count and prothrombin time, in estimating hemostasis in patients with cirrhosis. With identification of novel factors that contribute to bleeding risk in patients with cirrhosis, there is a dearth of clinical trial data that account for all potentially relevant factors and that examine interventions to reduce bleeding risk. Precise recommendations regarding transfusion strategies based on hemostatic test results in patients with cirrhosis are impractical.

In patients with cirrhosis with severe thrombocytopenia (platelet count [PC] <50 × 109 /L) and undergoing invasive procedures, it is common clinical practice to increase the PC with platelet transfusions or thrombopoietin receptor agonists to reduce the risk of major periprocedural bleeding. The aim of our study was to investigate the association between native PC and perioperative bleeding in patients with cirrhosis undergoing surgical procedures for the treatment of hepatocellular carcinoma (HCC). We retrospectively evaluated 996 patients with cirrhosis between 1996 and 2018 who underwent surgical treatments of HCC by liver resection (LR) or radiofrequency ablation (RFA) without prophylactic platelet transfusions. Patients were allocated to the following three groups based on PC: high (>100 × 109 /L), intermediate (51-100 × 109 /L), and low (≤50 × 109 /L). PC was also analyzed as a continuous covariate on multivariable analysis. The primary endpoint was major perioperative bleeding. The overall event rate of major perioperative bleeding was 8.9% and was not found to differ significantly between the high, intermediate, and low platelet groups (8.1% vs. 10.2% vs. 10.8%, P = 0.48). On multivariable analysis, greater age, aspartate aminotransferase, lower hemoglobin, and treatment with LR (vs. RFA) were found to be significant independent predictors of major perioperative bleeding, with associations with disease etiology and year of surgery also observed. After adjusting for these factors, the association between PC and major perioperative bleeding remained nonsignificant. Conclusion: Major perioperative bleeding was not significantly associated with PC in patients with cirrhosis undergoing surgical treatment of HCC, even when their PC was <50 × 109 /L. With the limit of a retrospective analysis, our data do not support the recommendation of increasing PC in patients with severe thrombocytopenia in order to decrease their perioperative bleeding risk.

Thrombopoietin receptor agonists (TPO-RAs) can mitigate preprocedural thrombocytopenia in patients with chronic liver disease (CLD) however their effects on procedural outcomes is unclear. In this meta-analysis, we aimed to better define the efficacy, thrombotic risk and bleeding mitigation associated with the use of preoperative TPO-RAs in patients with CLD. We performed a systematic review and meta-analysis of randomized placebo-controlled clinical trials to assess the use of preprocedural TPO-RAs in patients with CLD, searching MEDLINE, EMBASE and the Cochrane library database. Six publications comprising eight randomized trials (1229 patients; 717 received TPO-RAs, 512 received placebo) and three unique TPO-RAs were retrieved. The majority of the included procedures were endoscopic. TPO-RAs were significantly more likely to result in a preoperative platelet count greater than 50 x 109/L (72.1% vs 15.6%, RR 4.8, 95% CI 3.6-6.4 p < .00001. NNT 1.8) and reduced the incidence of platelet transfusions (22.5% vs 67.8%, RR 0.33, 95% CI 0.3-0.4 p < .00001. NNT 2.2). Total periprocedural bleeding was decreased in patients who received TPO-RAs (11.6% vs 15.6%, RR 0.64, 95% CI 0.5-0.9 p = .01. NNT 24.7) and there was no increase in the rate of thrombosis (2.2% vs 1.8% RR 1.25, 95% CI 0.6-2.9 p = .60. NNH 211.1). In patients with CLD the use of preprocedural TPO-RAs resulted in significant increased platelet counts, and decreased the incidence of platelet transfusions as compared to placebo. TPO use likewise decreased the incidence of total periprocedural bleeding without increasing the rate of thrombosis.