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SESSION TITLE: Problems in the Pleura Case Posters 1 SESSION TYPE: Case Report Posters PRESENTED ON: 10/17/2022 12:15 pm - 01:15 pm INTRODUCTION: Ibrutinib is an irreversible inhibitor of Bruton's tyrosine kinase (Btk), approved for treatment of a variety of B-cell malignancies, including chronic lymphocytic leukemia (CLL). There is an association of increased risk of bleeding with ibrutinib due to platelet dysfunction caused by the medication. Bleeding is usually non-life threating such as subcutaneous or mucosal bleeding, epistaxis, and ecchymosis. But major bleeding has been reported such as intracranial hemorrhage and gastrointestinal hemorrhage. Thoracic complications from ibrutinib are rare. Below is a case report discussing a hemorrhagic pleural effusion thought to be caused by Ibrutinib. CASE PRESENTATION: Patient is a 78-year-old male initially diagnosed with CLL on flow cytometry showing a low-grade B cell lymphoproliferative process. Patient was monitored by Hematology and when kappa light chain numbers began to rise, a bone marrow biopsy was performed showing 90% infiltration of the marrow with lymphoid cells. Patient was started on Ibrutinib therapy and responded well to treatment. A year after starting therapy, patient presented to the emergency room with increased shortness of breath and fatigue. Patient was found to be COVID-19 positive and chest x-ray showed a large right sided pleural effusion. Thoracentesis was performed draining 1650cc of bloody fluid. Fluid studies revealed a lymphocytic effusion with RBC count 1,185375, WBC of 1751. Cultures and cytology were negative. On further history, patient was without recent trauma or surgery, CTA chest was negative for pulmonary embolism. QuantiFERON Gold test was negative, indicating low likelihood of tuberculosis. Patient was not on any antiplatelet or systemic anticoagulation medications. Ibrutinib therapy was held during hospitalization and pleural effusion did not reaccumulate. Patient passed away during hospital stay secondary to respiratory failure due to COVID-19. DISCUSSION: Ibrutinib is an orally bioavailable bruton tyrosine kinase inhibitor (BTKi) and forms an irreversible covalent bound to BTK at the Cysteine-481 residue. Ibrutinib predisposes to bleeding by inhibiting BTK and Tec, which play a role in the inhibitory signaling pathway of platelet collagen receptors such as glycoprotein VI (GP VI) and C-type lectin-like receptor 2 (CLEC-2). Our patient had no other risk factors for developing a hemorrhagic effusion. CLL itself can cause malignant effusions, one study found the incidence of malignant effusions among patients with CLL to be 9%, but the effusion was noted to be serous or serosanguinous and there was pleural involvement in all patients which was not the case in our patient. CONCLUSIONS: There is currently a minimal amount of data to guide clinicians regarding the use of ibrutinib in patients at high risk of bleeding or on anticoagulant or antiplatelet therapy. It is important to realize bleeding complications related to ibrutinib therapy can occur. Reference #1: Shatzel JJ, Olson SR, Tao DL, McCarty OJT, Danilov AV, DeLoughery TG. Ibrutinib-associated bleeding: pathogenesis, management and risk reduction strategies. J Thromb Haemost. 2017;15(5):835-847. doi:10.1111/jth.13651 Reference #2: Burger JA, Tedeschi A, Barr PM, et al. Ibrutinib as Initial Therapy for Patients with Chronic Lymphocytic Leukemia. N Engl J Med. 2015;373(25):2425-2437. doi:10.1056/NEJMoa1509388 Reference #3: Paydas S. Management of adverse effects/toxicity of ibrutinib. Crit Rev Oncol Hematol. 2019;136:56-63. doi:10.1016/j.critrevonc.2019.02.001 DISCLOSURES: No relevant relationships by fatima ali No relevant relationships by Joan Wiley
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RATIONALE: The proteomic responses of hospitalized patients with SARS Co-V-2 infection may provide insight into risk, time course, and mechanisms associated with this infection. We used a high throughput proteomic platform to examine proteins that were differentially expressed relative to the length of hospital stay (LOS). METHOD:26 patients, hospitalized with SARS CoV-2 infection (mean age 48 yrs, 44% women) had blood samples obtained within 72 hours of admission. Initial plasma samples were analyzed from patients who were hospitalized for < 3 days (n=6), < 7days (n=12) and > 7 days (n=8) of LOS and compared to healthy controls (HC, n=8). Samples were analyzed with the modified aptamer-based array (SomaScan) that measures more than 7,000 human proteins representing different molecular pathways and gene families. Differentially regulated proteins with > 1.5 fold change and a false discovery rate of 5% were analyzed using the Ingenuity Pathway Analysis (IPA). Unique protein categories associated with LOS were assessed. RESULT: Compared to HC, differentially expressed proteins were detected among the 3 groups: 461 at < 3 days, 1,635 proteins at < 7 days and 1,738 proteins in >7 days. 407 proteins were common among all hospitalized COVID 19 individuals independent of LOS and 12, 250 and 361 proteins were uniquely present at < 3 days, < 7 days and > 7 days respectively compared to HC. The table below demonstrates the top highly enriched canonical pathway, molecular function and upstream regulator of differentially expressed proteins. The temporal sequence of these protein networks varied with LOS. Representative examples include early responses;platelet membrane glycoprotein GP6 signaling pathway that involves the FcR gamma-chain and the Src kinases linked to platelet aggregation, signaling involved in T cell receptor-mediated IL-2 production (TEC kinase). Less than 7 days include diacylglycerol associated with T cell activation, carnitine palmitoyltransferase associated with mitochondrial beta-oxidation of long chain fatty acids. CXCR4 a receptor for stromal -cell derived factor 1 and associated with COVID-19 prognosis. Late responses after 7 days include pathways involved in remodeling of epithelial adherens junctions. CONCLUSIONS : A high throughput proteomic approach provides insight into the dynamic regulation of protein pathways associated with the progression of SARS-Co-V2 infection. This may provide additional insight into risk and mechanisms associated with outcomes in COVID. (Table Presented).
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Background: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe prothrombotic complication of adenoviral vaccines including ChAdOx1 nCoV-19 (AstraZeneca) vaccine. The putative mechanism involves formation of pathological anti-PF4 antibodies that activate platelets via the FcγRIIa receptor to drive thrombosis and the associated thrombocytopenia. Functional assays are important in the VITT diagnostic pathway as not all detectable PF4 antibodies are pathogenic. Detection of procoagulant platelets (platelets supporting thrombin generation) in presence of PF4 has been proposed as a diagnostic assay for VITT (Althaus et al). Procoagulant platelets are not typically generated in response to low level agonist stimulation;however, combination of ligand binding of G-protein coupled receptors (GPCR) (eg. PAR1) and ITAM linked receptors (eg. GPVI, CLEC2 and FcγRIIa) synergistically induce procoagulant platelet formation. Here, we describe an alternative flow cytometric assay to diagnose VITT. We hypothesized that priming of platelets with a PAR1 agonist at a level sufficient to release PF4, but insufficient to generate a significant procoagulant response in donor platelets, would provide a platform in which procoagulant response would be dependent on presence of FcγRIIa dependent procoagulant antibodies in patient plasma, without requirement for additional PF4. Methods: Our previously established flow cytometry-based procoagulant platelet assay (using cell death marker GSAO and P-selectin) was modified to incorporate exogenous patient plasma and performed on whole blood from healthy donors screened for FcγRIIa responsiveness (aggregation response to anti-CD9 antibody, ALB6), primed with 5 μM SFLLRN. The assay was performed on Australian patients referred for confirmatory VITT testing with probable VITT (confirmed thrombosis within 4-42 days of ChAdOx1 nCov-19 vaccination, D-Dimer > 5x ULN, platelets < 150 x 10 9/L or falling platelet count) after screening on PF4/heparin ELISA (Asserachrom HPIA IgG Assay, Stago Diagnostics). Procoagulant response was also measured in presence of 0.5 U/mL and 100 U/mL heparin, monoclonal FcγRIIa blocking antibody, IV.3, and intravenous immunoglobulin, IVIg. Some plasmas were incubated with ChAdOx1 nCoV-19 or SARS-CoV-2 spike protein. Flow cytometry positive patients were also tested by serotonin release assay (SRA) and multiplate aggregometry. Clinical correlation was obtained. Results: Citrated plasma from 49 unique patients with suspected VITT are reported. Plasma from ELISA+ve patients with clinical picture consistent with VITT (n=31), significantly increased the procoagulant platelet proportions in healthy donors in presence of 5 μM SFLLRN (p<0.0001, Figure 1A). This increase was not seen with plasma from healthy donors (n=14);or individuals exposed to ChAdOx1 nCov-19 vaccine without VITT: thrombocytopenic thrombosis patients who were ELISA-ve and SRA-ve (n=14);or low-level ELISA+ve patients without thrombocytopenia who were negative by either multiplate or SRA (n=4). The procoagulant platelet response induced by VITT positive plasma was reduced with low dose heparin (0.5 U/mL, p<0.01) except for 3 patients who showed a heparin-enhancing effect (Figure 1B). High dose heparin (100 U/mL, p<0.0001), IV.3 (10 µg/mL, p<0.0001) or IVIg (10 mg/mL, p<0.0001) abolished the procoagulant response (Figures 1C-D). The in vitro effect of IVIg was predictive of the in vivo response to IVIg therapy (Figure 1E). Addition of SARS-CoV-2 spike protein had no effect on the procoagulant platelet response. ChAdOx1 nCov-19 had an inconsistent effect on procoagulant platelet formation in presence of VITT plasma. Use of donors without a robust aggregation response to ALB6 resulted in false negative results. Conclusion: Induction of FcγRIIa dependent procoagulant response by patient plasma, suppressible by high dose heparin and IVIg, is highly indicative of VITT in the correct clinical circumstance. This assay modification of priming donor platelets from known FcγRIIa responsive donors ith a GPCR agonist to potentiate the ITAM signaling from platelet activating immune complexes, results in a sensitive and specific assay. This may represent a functional platform that can be adopted into diagnostic laboratories to identify patients with platelet-activating antibodies and potentially predict treatment responses. [Formula presented] Disclosures: No relevant conflicts of interest to declare.