Thrombocytopenia and the effect of platelet transfusions on the occurrence of intracranial hemorrhage in patients with acute leukemia - a nested case-control study

Data mining and safety analysis of avatrombopag: a retrospective pharmacovigilance study based on the US food and drug administration's adverse event reporting system

With its increasing use in the treatment of thrombocytopenia, avatrombopag's associated adverse events (AEs) pose a major challenge to its clinical application. This study aims to comprehensively study AEs associated with avatrombopag by using real-world evidence. We curated AE reports for avatrombopag from the first quarter of 2018 to the fourth quarter of 2023 in the US Food and Drug Administration's Adverse Event Reporting System (FAERS) database. AEs were coded using the Medical Dictionary for Regulatory Activities of Preferred Terms and System Organ Classes. The reporting odds ratio, proportional reporting ratio, Bayesian confidence propagation neural network, and multi-item Gamma-Poisson Shrinker were used to investigate the relationship between avatrombopag and AE reports. Among 9,060,312 reported cases in the FAERS database, 1211 reports listed avatrombopag as "primary suspected" drug. Disproportionality analysis identified 44 preferred terms across 17 organ systems met the criteria for at least one of the four algorithms. The most commonly reported AEs were platelet count decreased (20.2%), headache (16.7%), platelet count increased (11.9%), platelet count abnormal (6.3%), contusion (2.7%), pulmonary embolism (2.3%), and deep vein thrombosis (2.1%). Unexpected AEs such as seasonal allergy, rhinorrhea, antiphospholipid syndrome, ear discomfort, and photopsia were also observed. Excluding the other serious outcomes, hospitalization (34.6%) was the most frequently reported serious outcome, followed by death (15.4%). Most reported AEs occurred within the first 2 days of initiating avatrombopag therapy, and the median onset time was 60 days. We identified new and unexpected AEs with clinical use of avatrombopag, and our results may provide valuable information for clinical monitoring and identifying risks associated with avatrombopag.

Middle Meningeal Artery Embolization in Acute Leukemia Patients Presenting With Subdural Hematoma

Intracerebral hemorrhage is a potentially fatal complication in patients with acute leukemia and contributing factors include thrombocytopenia and coagulopathy. Patients with acute leukemia may develop subdural hematoma (SDH) spontaneously or secondary to trauma. In patients with acute leukemia and SDH, the surgical evacuation of the hematoma causes significant morbidity and mortality. New approaches and strategies to reduce the need for surgical evacuation are needed to improve outcomes in patients with acute leukemia and intracerebral hemorrhage. We report two cases of acute SDH in patients with acute leukemia successfully treated with middle meningeal artery embolization, a minimally invasive interventional radiology technique, obviating the need for a surgical intervention. The first patient with acute promyelocytic leukemia (APL) presented with coagulopathy and developed an acute SDH after a fall. The second patient with acute myeloid leukemia presented with gum bleeding and also sustained an acute SDH after a fall. Both patients underwent middle meningeal artery embolization for treating their SDHs while actively receiving induction chemotherapy for acute leukemia. Both patients had resolution of their acute SDH and are in remission from their acute leukemia. Middle meningeal artery embolization is a very effective, and within the context of this setting, a novel, minimally invasive technique for management of SDH in acute leukemia patients, which can prevent the need for surgical interventions with its associated comorbidities and high risk of fatal outcomes in patients with acute leukemia and acute SDH.

Effect of decreased platelets on postoperative recurrence of chronic subdural hematoma

Introduction

Chronic subdural hematoma (CSDH) is commonly treated using simple burr hole surgery. However, postoperative recurrence occurs at a relatively high rate of 10-20%. A decrease in platelet count (PC) may be associated with recurrence via a hemostasis disorder; however, this association has not been well-studied. Therefore, this study aimed to investigate the association between PC and postoperative CSDH recurrence.

Methods

We retrospectively reviewed the data for CSDHs in 488 cerebral hemispheres of 431 patients who underwent burr hole surgery at our institution between January 2013 and December 2022. The association between preoperative PC and postoperative CSDH recurrence was investigated. We used the first quartile of PC, PC < 170 × 103/μL to define a threshold for decreased PC.

Results

In total, 459 cerebral hemispheres with CSDHs in 405 patients were followed up postoperatively for at least 3 months or until CSDH disappeared. CSDH recurred in 39 (8.5%) cerebral hemispheres. The recurrence rate was gradually increased in parallel with a decreasing PC. Among 109 CSDHs with a decreased PC (<170 × 103/μL), 15 (13.8%) recurred, whereas only 24 (6.9%) of 350 CSDHs without a decreased PC recurred (p = 0.03). In univariable logistic analysis, eosinophil-rich blood (≥100/μL eosinophils in peripheral blood) and a decreased PC were significant risk factors. Multivariable analysis showed that eosinophil-rich blood (adjusted odds ratio, 2.51; 95% confidence interval, 1.26-4.99; p = 0.009) and a decreased PC (adjusted odds ratio, 2.15; 95% confidence interval, 1.07-4.35; p = 0.03) were independent risk factors for recurrence.

Conclusion

Our study showed that a decrease in PC was associated with postoperative CSDH recurrence. Patients with CSDH and a decreased PC require careful postoperative follow-up.

Gilteritinib and the risk of intracranial hemorrhage: a case series of a possible, under-reported side effect

Gilteritinib is currently approved for patients with relapsed/refractory AML with FLT3 mutations, based on the positive results of the pivotal ADMIRAL study. In ADMIRAL trial, no increased risk of bleeding was reported, but in the previous dose finding study, a single event of intracranial hemorrhage (ICH) was registered after exposure to subtherapeutic doses of gilteritinib. Here, we report the first case series on five ICHs diagnosed in patients with FLT3-mutated AML, occurred within the first month of exposure to gilteritinib. Our cohort included 24 patients treated in three Italian centers. Most of these ICH cases were non-severe and self-limiting, while one was fatal. This link with ICHs remains in any case uncertain for the presence of active AML. We further reported that an analysis of the post-marketing surveillance data (EudraVigilance) retrieved other 11 cases of ICHs present in the database after gilteritinib treatment. A causality assessment was performed according to the Dx3 method to evaluate the possibility that ICHs might be an actual side effect of gilteritinib. In conclusion, further research is needed to elucidate the potential role of gilteritinib in the pathogenesis of ICHs.

A Rare Case of Relapsed Sarcoidosis Presenting As Severe Thrombocytopenia Associated With Intracerebral Hemorrhage Due to Bone Marrow Involvement

Sarcoidosis is a systemic granulomatous disease characterized by the hyperactivation of CD4 T cells, CD8 T cells, and macrophages. Clinical presentations of sarcoidosis are highly variable. Sarcoidosis is unknown in its etiology, but it suggests it may result from exposure to specific environmental agents in genetically susceptible people. Sarcoidosis commonly involves the lungs and lymphoid system. Bone marrow involvement in sarcoidosis is uncommon. Sarcoidosis rarely results in intracerebral hemorrhage due to severe thrombocytopenia secondary to bone marrow involvement. We present the case of a 72-year-old woman who has been in remission from sarcoidosis for 15 years and developed intracerebral hemorrhage secondary to severe thrombocytopenia due to sarcoidosis recurrence in the bone marrow. The patient presented to the emergency department with a generalized, non-blanching petechiae rash and nose and gum bleeding. Her labs showed a platelet count of less than 10.000/mcL, and computed tomography (CT) showed intracerebral hemorrhage. A bone marrow biopsy revealed a small, non-caseating granuloma indicative of a sarcoidosis relapse in the bone marrow.

Challenging Cases in Cerebrovascular Disease

Disorders involving the vascular system of the brain are numerous and sundry. Atherosclerotic thromboembolism of large vessels and lacunar infarctions of small vessel disease are well known. Brain infarction due to cardioembolism is common as well, and even more so when diligently sought. Rupture of intracranial blood vessels results in subarachnoid and intraparenchymal hemorrhage. We present four cases of stroke of uncommon cause and remind clinicians to be open minded to the many possible causes of stroke, in particular because early recognition and treatment is often critical. Case 1 discusses a patient with inflammatory cerebral amyloid angiopathy. The presentation, ability to recur, and current treatment considerations are reviewed. Case 2 discusses microangiopathic thrombotic angiopathy. Diagnosis and treatment are considered. An association with interferon therapy and the evolving terminology of this and related conditions are discussed. Case 3 discusses intracranial hemorrhage secondary to acute promyelocytic leukemia. Patients with acute leukemias require aggressive management of their coagulopathy, thrombocytopenia, and the disease itself. Finally, Case 4 discusses ischemic stroke due to a paradoxical embolism in the setting of a patent foramen ovale (PFO). Both medical and surgical management of a PFO for stroke prevention are considered.

Platelet-Acute Leukemia Interactions

Acute leukemia (AL) is a hematological malignancy with high morbidity and mortality that is caused by abnormal hematopoietic stem cells. AL can change the parameters, quality, and function of platelets through numerous mechanisms, resulting in bleeding and even death in AL patients. Hence, AL patients are often clinically treated using normal platelet transfusion. However, studies have found that platelets can also affect AL cells. This review discusses the changes occurring in platelet count, mean platelet volume, platelet distribution width, reticulated platelets, platelet membrane glycoprotein, platelet aggregation, and activation in AL patients, the causes of these changes, and the possible significance of these changes for patient prognosis. The effects of platelets on the proliferation and drug resistance of AL cells are also discussed.

Association between cardiovascular risk factors and intracranial hemorrhage in patients with acute leukemia

BACKGROUND

Intracranial hemorrhage is seen more frequently in acute leukemia patients compared to the general population. Besides leukemia related risk factors, also risk factors that are present in the general population might contribute to hemorrhagic complications in leukemia patients. Of those, cardiovascular risk factors leading to chronic vascular damage could modulate the occurrence of intracranial hemorrhage in these patients, as during their disease and treatment acute endothelial damage occurs due to factors like thrombocytopenia and inflammation.

OBJECTIVES

Our aim was to explore if cardiovascular risk factors can predict intracranial hemorrhage in acute leukemia patients.

METHODS

In a case control study nested in a cohort of acute leukemia patients, including 17 cases with intracranial hemorrhage and 55 matched control patients without intracranial hemorrhage, data on cardiovascular risk factors was collected for all patients. Analyses were performed via conditional logistic regression.

RESULTS

Pre-existing hypertension and ischemic heart disease in the medical history were associated with intracranial hemorrhage, with an incidence rate ratio of 12.9 (95% confidence interval (CI) 1.5 to 109.2) and 12.1 (95% CI 1.3 to110.7), respectively.

CONCLUSION

Both pre-existing hypertension and ischemic heart disease seem to be strong predictors of an increased risk for intracranial hemorrhage in leukemia patients.

Contribution of Various Types of Transfusion to Acute and Delayed Intracerebral Hemorrhage Injury

Intracerebral hemorrhage (ICH) is the second most prevalent type of stroke, after ischemic stroke, and has exceptionally high morbidity and mortality rates. After spontaneous ICH, one primary goal is to restrict hematoma expansion, and the second is to limit brain edema and secondary injury. Various types of transfusion therapies have been studied as treatment options to alleviate the adverse effects of ICH etiopathology. The objective of this work is to review transfusions with platelets, fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), and red blood cells (RBCs) in patients with ICH. Furthermore, tranexamic acid infusion studies have been included due to its connection to ICH and hematoma expansion. As stated, the first line of therapy is limiting bleeding in the brain and hematoma expansion. Platelet transfusion is used to promote recovery and mitigate brain damage, notably in patients with severe thrombocytopenia. Additionally, tranexamic acid infusion, FFP, and PCC transfusion have been shown to affect hematoma expansion rate and volume. Although there is limited available research, RBC transfusions have been shown to cause higher tissue oxygenation and lower mortality, notably after brain edema, increases in intracranial pressure, and hypoxia. However, these types of transfusion have varied results depending on the patient, hemostasis status/blood thinner, hemolysis, anemia, and complications, among other variables. Inconsistencies in published results on various transfusion therapies led us to review the data and discuss issues that need to be considered when establishing future guidelines for patients with ICH.

Expected individual benefit of prophylactic platelet transfusions in hemato-oncology patients based on bleeding risks

BACKGROUND

Prophylactic platelet transfusions prevent bleeding in hemato-oncology patients, but it is unclear how any benefit varies between patients. Our aim was to assess if patients with different baseline risks for bleeding benefit differently from a prophylactic platelet transfusion strategy.

STUDY DESIGN AND METHODS

Using the data from the randomized controlled TOPPS trial (Trial of Platelet Prophylaxis), we developed a prediction model for World Health Organization grades 2, 3, and 4 bleeding risk (defined as at least one bleeding episode in a 30 days period) and grouped patients in four risk-quartiles based on this predicted baseline risk. Predictors in the model were baseline platelet count, age, diagnosis, disease modifying treatment, disease status, previous stem cell transplantation, and the randomization arm.

RESULTS

The model had a c-statistic of 0.58 (95% confidence interval [CI] 0.54-0.64). There was little variation in predicted risks (quartiles 46%, 47%, and 51%), but prophylactic platelet transfusions gave a risk reduction in all risk quartiles. The absolute risk difference (ARD) was 3.4% (CI -12.2 to 18.9) in the lowest risk quartile (quartile 1), 7.4% (95% CI -8.4 to 23.3) in quartile 2, 6.8% (95% CI -9.1 to 22.9) in quartile 3, and 12.8% (CI -3.1 to 28.7) in the highest risk quartile (quartile 4).

CONCLUSION

In our study, generally accepted bleeding risk predictors had limited predictive power (expressed by the low c-statistic), and, given the wide confidence intervals of predicted ARD, could not aid in identifying subgroups of patients who might benefit more (or less) from prophylactic platelet transfusion.