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Mukherjee A, Gentille C, Patel A, Ensor J, Rice L. Heparin-induced thrombocytopenia with very high antibody titer is associated with slower platelet recovery and higher risk of thrombosis. Int J Hematol 2024; 120:290-296. [PMID: 38976179 DOI: 10.1007/s12185-024-03811-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 06/06/2024] [Accepted: 06/24/2024] [Indexed: 07/09/2024]
Abstract
Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder mediated by platelet-activating antibodies targeting platelet factor 4 (PF4) and heparin complex. A higher antibody titer is reflected in a higher optical density (OD) by enzyme-linked immunosorbent assay for heparin-PF4 antibodies. This single-institution retrospective study of 116 HIT patients examined the effect of heparin-PF4 OD on time to platelet recovery, vascular thrombosis, and in-hospital mortality. Patients were divided into 3 cohorts based on heparin-PF4 OD: cohort 1 had an OD ≥ 2 and ≤ 2.4, cohort 2 had an OD > 2.4 and ≤ 2.8, and cohort 3 had an OD > 2.8. A higher OD titer was associated with significantly increased time to platelet recovery when compared between cohorts 1 versus 2 (HR = 0.599, p = 0.0221) and 1 versus 3 (HR = 0.515, p = 0.0014), as well as an increased risk of thrombosis (79.4%-cohort 3 vs 53.8%-cohort 2 vs 46.1%-cohort 1, p = 0.04), but had no impact on mortality (2.62-alive vs 2.65-deceased, p = 0.7432). A higher OD titer can inform risk assessment and support decision-making in HIT patients; however, prospective studies are needed to further clarify the impact of heparin-PF4 OD on outcomes.
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Affiliation(s)
- Akash Mukherjee
- Department of Hematology and Oncology, Houston Methodist Hospital, Houston, TX, USA
| | - Cesar Gentille
- Department of Hematology and Oncology, Houston Methodist Hospital, Houston, TX, USA.
| | - Asmita Patel
- Department of Hematology and Oncology, Global Cancer Research Institute, San Jose, CA, USA
| | - Joe Ensor
- Department of Hematology and Oncology, Houston Methodist Hospital, Houston, TX, USA
| | - Lawrence Rice
- Department of Hematology and Oncology, Houston Methodist Hospital, Houston, TX, USA
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2
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Sugraliyev AB. [Heparin-Induced Thrombocytopenia]. KARDIOLOGIIA 2024; 64:18-25. [PMID: 38841785 DOI: 10.18087/cardio.2024.5.n2186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 10/28/2022] [Indexed: 06/07/2024]
Abstract
The extensive use of therapeutic doses of heparin to prevent thrombosis in critically ill patients with COVID-19 during the pandemic has led to an increased incidence of bleeding and heparin-induced thrombocytopenia (HIT). In addition, the introduction of the AstraZeneca and Johnson&Johnson vaccines against COVID-19 into clinical practice was associated with the development of a rare but very severe, adverse thrombotic complication, vaccine-induced immune thrombotic thrombocytopenia (VITT). Thrombotic complications of VITT turned out to be similar to HIT both clinically and pathophysiologically. HIT is a potentially fatal immune-mediated adverse drug response that results in emergence of antibodies that activate platelets in the presence of heparin. HIT is characterized by a high incidence of venous and arterial thromboses, often with fatal outcomes. Currently, there are clearly defined international guidelines for the diagnosis, treatment and prevention of HIT. In case of thrombotic complications, non-heparin anticoagulants should be used.
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Abdelouahed M, Yateem D, Fredericks S. Fc γRIIa - dependent platelet activation identified in COVID-19 vaccine-induced immune thrombotic thrombocytopenia-, heparin-induced thrombocytopenia, streptokinase- and anisoylated plasminogen-streptokinase activator complex-induced platelet activation. Front Cardiovasc Med 2023; 10:1282637. [PMID: 38034388 PMCID: PMC10684751 DOI: 10.3389/fcvm.2023.1282637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19), which was caused by the coronavirus - severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was globally responsible for remarkable morbidity and mortality. Several highly effective vaccines for COVID-19 were developed and disseminated worldwide within an unprecedented timescale. Rare but dangerous clotting and thrombocytopenia events, and subsequent coagulation abnormalities, have been reported after massive vaccination against SARS-CoV-2. Soon after their global rollout, reports of a morbid clinical syndrome following vaccination with adenovirus-DNA-based vaccines appeared. In the spring of 2021, reports of a novel, rare and morbid clinical syndrome, with clinically devastating and fatal complication after vaccination with adenovirus-based coronavirus vaccines (Janssen/Johnson & Johnson and Astra-Zeneca vaccines) led to a brief suspension of their use by several countries. Those complications were associated with unusual cerebral and splanchnic venous thrombosis, and circulating autoantibodies directed against anti-platelet factor 4 (PF4), a protein secreted from platelets, leading to the designation: Vaccine-Induced Immune Thrombotic Thrombocytopenia (VITT). The reported VITT incidence remains very low and does not affect the overall benefit of immunization, however, if left untreated, VITT can be debilitating or even fatal. VITT resembled specific adverse drugs' reactions that also involved the production of autoantibodies and subsequent abnormal platelet activation through platelet FcγRIIa. These unusual but well-documented drug reactions were heparin-induced thrombocytopenia (HIT), streptokinase- (SK), and anisoylated plasminogen-streptokinase activator complex- (APSAC) associated with platelet-activating antibodies. There was considerable overlapping of clinical features between VITT, COVID-19 and these adverse drugs' reactions. We review the phenomenon of VITT against the backdrop of shared and common mechanisms that underlie HIT-, SK-, and APSAC-platelet FcγRIIa-dependent platelet activation. An understanding of VITT's pathogenesis may be achieved by comparing and contrasting VITT-, HIT-, SK- and APSAC-induced platelet activation mechanisms, their respective physiopathology and similarities. Discussing these conditions in parallel provides insight into complex immunological disorders and diseases associated with abnormal hemostasis and thrombosis in particular.
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Affiliation(s)
- Mustapha Abdelouahed
- Department of Medical Sciences and Education, Boston University School of Medicine, Boston, MA, United States
| | - Dana Yateem
- School of Medicine, The Royal College of Surgeons in Ireland, Medical University of Bahrain, Al Sayh, Muharraq Governorate, Bahrain
| | - Salim Fredericks
- School of Medicine, The Royal College of Surgeons in Ireland, Medical University of Bahrain, Al Sayh, Muharraq Governorate, Bahrain
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4
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Rollin J, Charuel N, Gruel Y, Billy S, Guéry E, May M, Pouplard C, Vayne C. Variable serotonin release assay pattern and specificity of PF4-specific antibodies in HIT, and clinical relevance. J Thromb Haemost 2022; 20:2646-2655. [PMID: 35971886 PMCID: PMC9826218 DOI: 10.1111/jth.15848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 01/11/2023]
Abstract
BACKGROUND The diagnosis of heparin-induced thrombocytopenia (HIT) requires functional assays to demonstrate that platelet factor 4 (PF4)-specific antibodies activate platelets, typically when therapeutic heparin (H) concentrations are tested ("classical" pattern). Some HIT samples also activate platelets without heparin ("atypical" pattern), but with unclear clinical significance. OBJECTIVES We aimed to assess whether platelet activation pattern and some characteristics of PF4-specific antibodies were associated with the severity of HIT. PATIENTS/METHODS Serotonin release assay (SRA) pattern of 81 HIT patients were analyzed and compared with their clinical and biological data, including levels of anti-PF4/H immunoglobulin G (IgG) and anti-PF4 IgG in 47 of them. RESULTS Higher anti-PF4/H IgG titers were measured in patients with an "atypical" SRA (optical density 2.52 vs. 1.94 in those with a "classical" pattern, p < .001). Patients of both groups had similar platelet count (PC) nadir and time to recovery, but those with an "atypical" SRA more frequently developed thrombotic events (69% vs. 34%, p = .037). Significant levels of anti-PF4 IgG were detected in both groups (38% and 61%, respectively). Whatever the SRA pattern, a lower PC nadir (35 vs. 53 G/L, p = .006) and a longer PC recovery time (6 vs. 3 days, p = .015) were evidenced in patients with anti-PF4 antibodies, compared with those with anti-PF4/H IgG only. CONCLUSIONS An atypical SRA pattern with elevated anti-PF4/H IgG titers seems associated with an increased risk of thrombosis in HIT. IgG antibodies to native PF4 may contribute to more severe and persistent thrombocytopenia, and their detection could be useful in clinical practice.
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Affiliation(s)
- Jérôme Rollin
- University of ToursToursFrance
- Department of HaemostasisRegional University Hospital Centre ToursToursFrance
| | | | - Yves Gruel
- University of ToursToursFrance
- Department of HaemostasisRegional University Hospital Centre ToursToursFrance
| | | | - Eve‐Anne Guéry
- Department of HaemostasisRegional University Hospital Centre ToursToursFrance
| | - Marc‐Antoine May
- Department of Cardiovascular SurgeryRegional University Hospital Centre ToursToursFrance
- Department of AnesthesiologyRegional University Hospital Centre ToursToursFrance
| | - Claire Pouplard
- University of ToursToursFrance
- Department of HaemostasisRegional University Hospital Centre ToursToursFrance
| | - Caroline Vayne
- University of ToursToursFrance
- Department of HaemostasisRegional University Hospital Centre ToursToursFrance
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5
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Aguiar de Sousa D, Romoli M, Sánchez Van Kammen M, Heldner MR, Zini A, Coutinho JM, Arnold M, Ferro JM. Cerebral Venous Thrombosis in Patients With Heparin-Induced Thrombocytopenia a Systematic Review. Stroke 2022; 53:1892-1903. [PMID: 35240862 DOI: 10.1161/strokeaha.121.036824] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Cerebral venous thrombosis (CVT) has recently been reported as a common thrombotic manifestation in association with vaccine-induced thrombotic thrombocytopenia, a syndrome that mimics heparin-induced thrombocytopenia (HIT) and occurs after vaccination with adenovirus-based SARS-CoV-2 vaccines. We aimed to systematically review the incidence, clinical features, and prognosis of CVT occurring in patients with HIT. METHODS The study protocol was registered with PROSPERO (CRD42021249652). MEDLINE, EMBASE and Cochrane CENTRAL were searched up to June 1, 2021 for HIT case series including >20 patients, or any report of HIT-related CVT. Demographic, neuroradiological, clinical, and mortality data were retrieved. Meta-analysis of proportions with random-effect modeling was used to derive rate of CVT in HIT and in-hospital mortality. Pooled estimates were compared with those for CVT without HIT and HIT without CVT, to determine differences in mortality. RESULTS From 19073 results, we selected 23 case series of HIT (n=1220) and 27 cases of HIT-related CVT (n=27, 71% female). CVT developed in 1.6% of 1220 patients with HIT (95% CI,1.0%-2.5%, I2=0%). Hemorrhagic brain lesions occurred in 81.8% of cases of HIT-related CVT and other concomitant thrombosis affecting other vascular territory was reported in 47.8% of cases. In-hospital mortality was 33.3%. HIT-related CVT carried a 29% absolute increase in mortality rate compared with historical CVT controls (33.3% versus 4.3%, P<0.001) and a 17.4% excess mortality compared with HIT without CVT (33.3% versus 15.9%, P=0.046). CONCLUSIONS CVT is a rare thrombotic manifestation in patients with HIT. HIT-related CVT has higher rates of intracerebral hemorrhage and a higher mortality risk, when compared with CVT in historical controls. The recently reported high frequency of CVT in patients with vaccine-induced thrombotic thrombocytopenia was not observed in HIT, suggesting that additional pathophysiological mechanisms besides anti-platelet factor-4 antibodies might be involved in vaccine-induced thrombotic thrombocytopenia-related CVT.
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Affiliation(s)
- Diana Aguiar de Sousa
- Department of Neurology, Centro Hospitalar Universitário de Lisboa Norte - Hospital de Santa Maria, Lisbon, Portugal (D.A.d.S., J.M.F.).,Faculdade de Medicina, Universidade de Lisboa, Portugal (D.A.d.S., J.M.F.)
| | - Michele Romoli
- Neurology and Stroke Unit, "Maurizio Bufalini" Hospital, Cesena, Italy (M.R.).,Neurology Clinic, University of Perugia - S. Maria della Misericordia Hospital, Italy (M.R.)
| | - Mayte Sánchez Van Kammen
- Department of Neurology, Amsterdam University Medical Center, the Netherlands (M.S.V.K., J.M.C.)
| | - Mirjam R Heldner
- Department of Neurology, University hospital and University of Bern, Switzerland (M.R.H., M.A.)
| | - Andrea Zini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Neurologia e Rete Stroke Metropolitana, Ospedale Maggiore, Bologna, Italy (A.Z.)
| | - Jonathan M Coutinho
- Department of Neurology, Amsterdam University Medical Center, the Netherlands (M.S.V.K., J.M.C.)
| | - Marcel Arnold
- Department of Neurology, University hospital and University of Bern, Switzerland (M.R.H., M.A.)
| | - José M Ferro
- Department of Neurology, Centro Hospitalar Universitário de Lisboa Norte - Hospital de Santa Maria, Lisbon, Portugal (D.A.d.S., J.M.F.).,Faculdade de Medicina, Universidade de Lisboa, Portugal (D.A.d.S., J.M.F.)
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6
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Arepally GM, Ortel TL. Vaccine-induced immune thrombotic thrombocytopenia: what we know and do not know. Blood 2021; 138:293-298. [PMID: 34323940 PMCID: PMC8172307 DOI: 10.1182/blood.2021012152] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 05/27/2021] [Indexed: 02/08/2023] Open
Abstract
The development of vaccines to fight COVID-19 has been a remarkable medical achievement. However, this global immunization effort has been complicated by a rare vaccine-related outcome characterized by thrombocytopenia and thrombosis in association with platelet-activating anti-platelet factor 4 antibodies. In this Spotlight, we will discuss the recently described complication of vaccine-induced immune thrombotic thrombocytopenia (VITT) occurring in response to certain COVID-19 vaccines. Although information about this clinical condition is rapidly evolving, we will summarize our current understanding of VITT.
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Affiliation(s)
| | - Thomas L Ortel
- Division of Hematology, Duke University Medical Center, Durham, NC
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7
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Zaydman MA, Brestoff JR, Jackups R. Using information theory to optimize a diagnostic threshold to match physician-ordering practice. J Biomed Inform 2021; 117:103756. [PMID: 33766781 DOI: 10.1016/j.jbi.2021.103756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Clinicians order laboratory tests in an effort to reduce diagnostic or therapeutic uncertainty. Information theory provides the opportunity to quantify the degree to which a test result is expected to reduce diagnostic uncertainty. We sought to apply information theory toward the evaluation and optimization of a diagnostic test threshold and to determine if the results would differ from those of conventional methodologies. We used a heparin/PF4 immunoassay (PF4 ELISA) as a case study. MATERIALS AND METHODS The laboratory database was queried for PF4 ELISA and serotonin release assay (SRA) results during the study period, with the latter serving as the gold standard for the disease heparin-induced thrombocytopenia (HIT). The optimized diagnostic threshold of the PF4 ELISA test was compared using conventional versus information theoretic approaches under idealized (pretest probability = 50%) and realistic (pretest probability = 2.4%) testing conditions. RESULTS Under ideal testing conditions, both analyses yielded a similar optimized optical density (OD) threshold of OD > 0.79. Under realistic testing conditions, information theory suggested a higher threshold, OD > 1.5 versus OD > 0.6. Increasing the diagnostic threshold improved the global information value, the value of a positive test and the noise content with only a minute change in the negative test value. DISCUSSION Our information theoretic approach suggested that the current FDA approved cutoff (OD > 0.4) is overly permissive leading to loss of test value and injection of noise into an already complex diagnostic dilemma. Because our approach is purely statistical and takes as input data that are readily accessible in the clinical laboratory it offers a scalable and data-driven strategy for optimizing test value that may be widely applicable in the domain of laboratory medicine. CONCLUSION Information theory provides more meaningful measures of test value than the widely used accuracy-based metrics.
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Affiliation(s)
- Mark A Zaydman
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, USA.
| | - Jonathan R Brestoff
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, USA
| | - Ronald Jackups
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, USA
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8
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Abstract
Heparin-induced thrombocytopenia is an immune-mediated disorder caused by antibodies that recognize complexes of platelet factor 4 and heparin. Thrombosis is a central and unpredictable feature of this syndrome. Despite optimal management, disease morbidity and mortality from thrombosis remain high. The hypercoagulable state in heparin-induced thrombocytopenia is biologically distinct from other thrombophilic disorders in that clinical complications are directly attributable to circulating ultra-large immune complexes. In some individuals, ultra-large immune complexes elicit unchecked cellular procoagulant responses that culminate in thrombosis. To date, the clinical and biologic risk factors associated with thrombotic risk in heparin-induced thrombocytopenia remain elusive. This review will summarize our current understanding of thrombosis in heparin-induced thrombocytopenia with attention to its clinical features, cellular mechanisms, and its management.
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Affiliation(s)
| | - Anand Padmanabhan
- Divisions of Hematopathology, Transfusion Medicine, and Experimental Pathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN (A.P.)
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9
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Ezelsoy M, Saracoglu KT, Oral K, Saracoglu A, Akpinar B. Positive Heparin/PF4 Antibodies and High Mortality Rate: a Retrospective Case-Series Analysis. Braz J Cardiovasc Surg 2020; 35:950-957. [PMID: 33306320 PMCID: PMC7731847 DOI: 10.21470/1678-9741-2019-0360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Introduction Heparin-induced thrombocytopenia (HIT) is a potentially lethal complication of unfractionated or low-molecular weight heparin therapy. We aimed to determine the incidence and mortality rate of patients with positive heparin/platelet factor 4 (PF4) antibodies, which is a rapid detection test of HIT. Methods Coronary artery bypass grafting and mitral and aortic valve surgeries were evaluated. Cardiopulmonary bypass was employed in all patients. The diagnosis of HIT was based on immunological assays. Postoperative complications, mortality rates, and the causes of death were specified in patients with positive heparin/PF4 antibodies. Results Postoperative thrombocytopenia was detected in 257 patients. Twenty of these patients undergoing open heart surgery were included in the final analysis. Antibodies against heparin/PF4 complex were positive in 20 patients. The mean body mass index was 28.8±2.3 kg/m2, mean value of left ventricular ejection fraction was 48.3±6.7%, cardiopulmonary bypass time was 113.0±35.0 min, aortic cross-clamping time was 88.0±32.7 min, mean intensive care unit length of stay was 10.9±4.9 days, mean preoperative platelet count was 307.250±88528 platelets/microliter, and mean postoperative platelet count was 243.050±89.354 platelets/microliter. The mean duration of heparin exposure was 6.9±2.9 days. The mortality rate was 45% (nine patients) and 1.2% (three patients) in heparin/PF4 complex positive and negative patients, respectively. Conclusion Although the incidence of HIT was low in patients undergoing open heart surgery, an increased rate of early mortality was observed in patients with positive heparin/PF4 antibodies.
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Affiliation(s)
- Mehmet Ezelsoy
- Department of Cardiovascular Surgery, Istanbul Demiroglu Bilim University Medical School, Istanbul, Turkey
| | - Kemal Tolga Saracoglu
- Department of Anesthesiology and Intensive Care, Health Sciences University Medical School, Istanbul, Turkey
| | - Kerem Oral
- Department of Cardiovascular Surgery, Istanbul Demiroglu Bilim University Medical School, Istanbul, Turkey
| | - Ayten Saracoglu
- Department of Anesthesiology and Intensive Care, Istanbul Marmara University Medical School, Istanbul, Turkey
| | - Belhan Akpinar
- Department of Cardiovascular Surgery, Istanbul Demiroglu Bilim University Medical School, Istanbul, Turkey
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10
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Arepally GM, Cines DB. Pathogenesis of heparin-induced thrombocytopenia. Transl Res 2020; 225:131-140. [PMID: 32417430 PMCID: PMC7487042 DOI: 10.1016/j.trsl.2020.04.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/15/2020] [Accepted: 04/21/2020] [Indexed: 01/19/2023]
Abstract
There are currently no effective substitutes for high intensity therapy with unfractionated heparin (UFH) for cardiovascular procedures based on its rapid onset of action, ease of monitoring and reversibility. The continued use of UFH in these and other settings requires vigilance for its most serious nonhemorrhagic complication, heparin induced thrombocytopenia (HIT). HIT is an immune prothrombotic disorder caused by antibodies that recognize complexes between platelet factor 4 (PF4) and polyanions such as heparin (H).The pathogenicity of anti-PF4/H antibodies is likely due to the formation of immune complexes that initiate intense procoagulant responses by vascular and hematopoietic cells that lead to the generation of platelet microparticles, monocyte and endothelial cell procoagulant activity, and neutrophil extracellular traps, among other outcomes. The development of anti-PF4/H antibodies after exposure to UFH greatly exceeds the incidence of clinical disease, but the biochemical features that distinguish pathogenic from nonpathogenic antibodies have not been identified. Diagnosis relies on pretest clinical probability, screening for anti-PF4/H antibodies and documentation of their platelet activating capacity. However, both clinical algorithms and test modalities have limited predictive values making diagnosis and management challenging. Given the unacceptable rates of recurrent thromboembolism and bleeding associated with current therapies, there is an unmet need for novel rational nonanticoagulant therapeutics based on the pathogenesis of HIT. We will review recent developments in our understanding of the pathogenesis of HIT and its implications for future approaches to diagnosis and management.
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Affiliation(s)
- Gowthami M Arepally
- Division of Hematology, Duke University Medical Center, Durham, North Carolina.
| | - Douglas B Cines
- Department of Pathology and Laboratory Medicine, Perelman-University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
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11
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Association between the HLA-DRB1*03:01-DQB1*02:01 haplotype and PF4/heparin antibodies. Blood Adv 2020; 3:3136-3142. [PMID: 31648318 DOI: 10.1182/bloodadvances.2019000311] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 09/13/2019] [Indexed: 12/26/2022] Open
Abstract
Key Points
HLA-DRB1*03:01-DQB1*02:01 haplotype patients develop higher anti–platelet factor 4/heparin (PF4/H) levels following IV heparin exposure. HLA-restricted antigen presentation may play a role in the formation of anti-PF4/H antibodies.
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12
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Sahu KK, Jindal V, Anderson J, Siddiqui AD, Jaiyesimi IA. Current Perspectives on Diagnostic Assays and Anti-PF4 Antibodies for the Diagnosis of Heparin-Induced Thrombocytopenia. J Blood Med 2020; 11:267-277. [PMID: 32884385 PMCID: PMC7443028 DOI: 10.2147/jbm.s232648] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 07/27/2020] [Indexed: 12/12/2022] Open
Abstract
Heparin-induced thrombocytopenia (HIT) is a recognized clinical entity in patients receiving unfractionated heparin and low–molecular weight heparin. Currently, diagnosing HIT includes the combination of a physician’s clinical suspicion based on a clinical scoring system and a series of laboratory tests. In the present article, we discuss challenges in suspecting and diagnosing HIT in consideration of the turnaround time of available tests and recent advances in techniques and methodologies of newer immunoassays and functional assays.
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Affiliation(s)
- Kamal K Sahu
- Hemato-oncology Division, Department of Internal Medicine, Saint Vincent Hospital, Worcester, MA 01608, USA
| | - Vishal Jindal
- Department of Hematology and Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, MI 48073, USA
| | - Joseph Anderson
- Department of Hematology and Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, MI 48073, USA
| | - Ahmad D Siddiqui
- Hemato-oncology Division, Department of Internal Medicine, Saint Vincent Hospital, Worcester, MA 01608, USA
| | - Ishmael A Jaiyesimi
- Department of Hematology and Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, MI 48073, USA
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13
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Guzman AK, Balagula Y. Drug-induced cutaneous vasculitis and anticoagulant-related cutaneous adverse reactions: insights in pathogenesis, clinical presentation, and treatment. Clin Dermatol 2020; 38:613-628. [PMID: 33341196 DOI: 10.1016/j.clindermatol.2020.06.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Drug-induced vasculitis and anticoagulant-related skin reactions are commonly encountered in the inpatient and outpatient settings. The spectrum of clinical presentation is broad and ranges from focal, skin-limited disease, to more extensive cutaneous and soft tissue necrosis, to potentially fatal systemic involvement. The prompt recognition of these adverse events can have a significant impact on patient morbidity and mortality. We highlight the key features of the clinical presentation with an emphasis on primary lesion morphology, distribution, and epidemiology of purpuric drug reactions. The proposed pathophysiology, histologic findings, and therapeutic interventions of these potentially life-threatening diseases are discussed.
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Affiliation(s)
- Anthony K Guzman
- Division of Dermatology, Department of Internal Medicine, Albert Einstein College of Medicine, Bronx, New York, USA.
| | - Yevgeniy Balagula
- Division of Dermatology, Department of Internal Medicine, Albert Einstein College of Medicine, Bronx, New York, USA
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14
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Dhakal B, Kreuziger LB, Rein L, Kleman A, Fraser R, Aster RH, Hari P, Padmanabhan A. Disease burden, complication rates, and health-care costs of heparin-induced thrombocytopenia in the USA: a population-based study. LANCET HAEMATOLOGY 2018; 5:e220-e231. [PMID: 29703336 DOI: 10.1016/s2352-3026(18)30046-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/16/2018] [Accepted: 03/19/2018] [Indexed: 01/19/2023]
Abstract
BACKGROUND Heparin-induced thrombocytopenia can be a life-threatening and limb-threatening complication of heparin therapy. Incidence and complication rates of this condition have been extrapolated from studies with modest sample sizes, and despite the availability of therapeutic interventions the outcomes of heparin-induced thrombocytopenia are not well understood. We aimed to estimate disease burden, complication rates, and costs of heparin-induced thrombocytopenia in the USA. METHODS In this population-based study we analysed data from 2009 to 2013 from the Nationwide (National) Inpatient Sample (NIS), a large, all-payer inpatient health-care database in the USA. To validate the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code for heparin-induced thrombocytopenia (289.84), we defined the sensitivity and specificity of this code using patient data from 2013 from a local hospital (Froedtert Memorial Lutheran Hospital, Milwaukee, WI, USA). The primary outcomes assessed were the incidence of hospital discharges with codes for heparin-induced thrombocytopenia and of discharges for heparin-induced thrombocytopenia associated with cardiopulmonary bypass, haemodialysis, hip or knee arthroplasty, trauma or injury (or both), and gingival or periodontal disease (or both). We also assessed the incidence of thrombosis, bleeding, limb or digit amputation, mortality, length of hospital stay, and associated hospital charges. FINDINGS Between 2009 and 2013, 97 566 discharges from the NIS assigned the ICD-9-CM code for heparin-induced thrombocytopenia, and 149 911 247 discharges coded for non-heparin-induced thrombocytopenia, were analysed. Overall, heparin-induced thrombocytopenia was identified in 97 566 (0·065%; SE 0·0012) of 150 008 813 discharges, corresponding to approximately one in 1500 hospital admissions. Patients undergoing cardiopulmonary bypass had the highest rates of heparin-induced thrombocytopenia (7702 [0·63%; SE 0·03] of 1 230 362), followed by those undergoing haemodialysis (23 012 [0·47%; 0·01] of 4 908 100), those with gingival or periodontal disease, or both (106 [0·12%; 0·03] of 88 621), and those with trauma or injury, or both (541 [0·09%; 0·01] of 602 944); patients with hip (845 [0·04%; 0·004] of 1 943 353) and knee (676 [0·02%; 0·002] of 3 022 602) arthroplasty had the lowest rates of heparin-induced thrombocytopenia. Thrombosis (29 079 [29·8%; SE 0·4] of 97 566) and bleeding (6044 [6·2%; 0·2] of 97 566) were common complications in heparin-induced thrombocytopenia, and 1446 (23·9%; 1·2) of 6044 patients with heparin-induced thrombocytopenia who had haemorrhage died. 742 (0·76%; SE 0·06) of 97 566 patients with heparin-induced thrombocytopenia discharges underwent amputations compared with 173 043 (0·12%; 0·001) of 149 911 247 with non-heparin-induced thrombocytopenia discharges (adjusted odds ratio 5·095 [95% CI 4·309-6·023]; p<0·0001). Overall, in-hospital mortality was 9842 (10·1%; SE 0·2) of 97 508 in discharge summaries coded for heparin-induced thrombocytopenia compared with 3 206 700 (2·1%; 0·01) of 149 811 891 in discharges for non-heparin-induced thrombocytopenia (adjusted odds ratio 4·075 [95% CI 3·846-4·317]; p<0·0001). The median length of stay among live discharges was 8·9 days (IQR 4·6-17·1) and total hospital charges were US$83 072 (IQR 37 240-188 419) for heparin-induced thrombocytopenia discharges compared with 2·6 days (1·4-4·8) and $21 360 (11 426-41 917) for non-heparin-induced thrombocytopenia discharges (p<0·0001 for both). 333 discharges from a local hospital were analysed to assess the diagnostic sensitivity and specificity of the heparin-induced thrombocytopenia ICD-9-CM code; sensitivity was 90·9% (95% CI 57·1-99·5) and specificity was 94·4% (91·1-96·6). INTERPRETATION Complication rates for heparin-induced thrombocytopenia remain high and more effective preventive and treatment interventions are needed. FUNDING None.
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Affiliation(s)
- Binod Dhakal
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Lisa Baumann Kreuziger
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA; Medical Sciences Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA; Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA
| | - Lisa Rein
- Department of Biostatistics, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Ariel Kleman
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Raphael Fraser
- Department of Biostatistics, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Richard H Aster
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA; Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA
| | - Parameswaran Hari
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Anand Padmanabhan
- Department of Pathology, Medical College of Wisconsin, Milwaukee, WI, USA; Medical Sciences Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA; Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA.
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Rauova L, Arepally G, Poncz M, Cines DB. Molecular and cellular pathogenesis of heparin-induced thrombocytopenia (HIT). Autoimmun Rev 2018; 17:1046-1052. [PMID: 30103043 DOI: 10.1016/j.autrev.2018.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 05/09/2018] [Indexed: 01/19/2023]
Affiliation(s)
- Lubica Rauova
- Division of Hematology, Department of Pediatrics, Childrens Hospital of Philadelphia, USA; Department of Pediatrics, University of Pennsylvania, Perelman School of Medicine, USA
| | - Gowthami Arepally
- Division of Hematology, Department of Medicine, Duke University School of Medicine, USA
| | - Mortimer Poncz
- Division of Hematology, Department of Pediatrics, Childrens Hospital of Philadelphia, USA; Department of Pediatrics, University of Pennsylvania, Perelman School of Medicine, USA
| | - Douglas B Cines
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, USA; Department of Medicine, University of Pennsylvania, Perelman School of Medicine, USA.
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McKenzie DS, Anuforo J, Morgan J, Neculiseanu E. Successful Use of Intravenous Immunoglobulin G to Treat Refractory Heparin-Induced Thrombocytopenia With Thrombosis Complicating Peripheral Blood Stem Cell Harvest. J Investig Med High Impact Case Rep 2018; 6:2324709618755414. [PMID: 29404376 PMCID: PMC5791472 DOI: 10.1177/2324709618755414] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Revised: 12/10/2017] [Accepted: 12/14/2017] [Indexed: 12/13/2022] Open
Abstract
Heparin-induced thrombocytopenia is a well-known, life-threatening complication that occurs in 5% of patients exposed to heparin. It causes thrombocytopenia in roughly 85% to 90% of affected individuals, with expected recovery in approximately 4 to 10 days following heparin withdrawal. However, there is an entity known as refractory heparin-induced thrombocytopenia with thrombosis in which patients have prolonged thrombocytopenia, refractory to the current standard of care. We present one such case of a 48-year-old male with R-ISS (Revised International Staging System) stage II kappa light chain multiple myeloma in stringent complete response status postinduction therapy. He developed heparin-induced thrombocytopenia with thrombosis during peripheral blood stem cell harvesting, manifesting as acute right coronary artery thrombus and severe thrombocytopenia. Although his clinical course was prolonged, he was ultimately successfully treated with intravenous immunoglobulin G 500 mg/kg/day over 4 days.
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17
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Wong M, Oo TH, Qiao W, Garg N, Rojas-Hernandez CM. Performance of 4T score and heparin-platelet factor 4 antibody in the diagnosis of heparin-induced thrombocytopenia (HIT) in cancer. J Thromb Thrombolysis 2017; 44:261-266. [PMID: 28677022 DOI: 10.1007/s11239-017-1523-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Cancer patients have characteristics which significantly influence the 4T score and heparin-platelet factor 4 antibody (H-PF4 ab). Our aim was to determine among cancer patients the correlation of the 4T score and H-PF4 ab with the serotonin release assay (SRA). We performed a retrospective analysis of records of cancer patients in whom H-PF4 polyclonal (IgG, IgM and IgA) enzyme-linked immunosorbent assay (ELISA) and SRA were evaluated. Cases were defined as heparin induced thrombocytopenia (HIT) when SRA confirmed the diagnosis. Logistic regression model and the receiver operating characteristic curves were conducted to identify the optimal cutting point for the optical density (OD) and 4T score to discriminate the SRA status. Among 246 patients, the optimal cutoff of 4T score for HIT diagnosis was 5 (sensitivity 90.0%, specificity 73.6%), and the optimal cutoff of H-PF4 polyclonal ELISA OD was 1.004 (sensitivity 81.8%, specificity 97.0%). Our findings suggest that cancer patients may need higher cutoff values for the 4T score. Conventional H-PF4 ab testing seem to perform similarly for the diagnosis of HIT when compared to published data from non-cancer cohorts. Additional studies are necessary to confirm our findings.
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Affiliation(s)
- Myra Wong
- Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Thein Hlaing Oo
- Section of Benign Hematology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX, 77030, USA
| | - Wei Qiao
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX, 77030, USA
| | - Naveen Garg
- Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX, 77030, USA
| | - Cristhiam M Rojas-Hernandez
- Section of Benign Hematology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX, 77030, USA.
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18
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Salter BS, Weiner MM, Trinh MA, Heller J, Evans AS, Adams DH, Fischer GW. Heparin-Induced Thrombocytopenia: A Comprehensive Clinical Review. J Am Coll Cardiol 2017; 67:2519-32. [PMID: 27230048 DOI: 10.1016/j.jacc.2016.02.073] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/03/2016] [Accepted: 02/08/2016] [Indexed: 12/13/2022]
Abstract
Heparin-induced thrombocytopenia is a profoundly dangerous, potentially lethal, immunologically mediated adverse drug reaction to unfractionated heparin or, less commonly, to low-molecular weight heparin. In this comprehensive review, the authors highlight heparin-induced thrombocytopenia's risk factors, clinical presentation, pathophysiology, diagnostic principles, and treatment. The authors place special emphasis on the management of patients requiring procedures using cardiopulmonary bypass or interventions in the catheterization laboratory. Clinical vigilance of this disease process is important to ensure its recognition, diagnosis, and treatment. Misdiagnosis of the syndrome, as well as misunderstanding of the disease process, continues to contribute to its morbidity and mortality.
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Affiliation(s)
- Benjamin S Salter
- Department of Anesthesiology, Mount Sinai Medical Center, New York, New York.
| | - Menachem M Weiner
- Department of Anesthesiology, Mount Sinai Medical Center, New York, New York
| | - Muoi A Trinh
- Department of Anesthesiology, Mount Sinai Medical Center, New York, New York
| | - Joshua Heller
- Department of Anesthesiology, Mount Sinai Medical Center, New York, New York
| | - Adam S Evans
- Department of Anesthesiology, Mount Sinai Medical Center, New York, New York
| | - David H Adams
- Department of Cardiac Surgery, Mount Sinai Medical Center, New York, New York
| | - Gregory W Fischer
- Department of Anesthesiology, Mount Sinai Medical Center, New York, New York
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Bolbrinker J, Garbe E, Douros A, Huber M, Bronder E, Klimpel A, Andersohn F, Meyer O, Salama A, Kreutz R. Immobilization and high platelet count are associated with thromboembolic complications in heparin-induced thrombocytopenia. Pharmacoepidemiol Drug Saf 2017; 26:1149-1155. [DOI: 10.1002/pds.4235] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 03/24/2017] [Accepted: 04/23/2017] [Indexed: 01/22/2023]
Affiliation(s)
- Juliane Bolbrinker
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Edeltraut Garbe
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
- Department of Clinical Epidemiology; Leibniz Institute for Prevention Research and Epidemiology - BIPS; Bremen Germany
| | - Antonios Douros
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Matthias Huber
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Elisabeth Bronder
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Andreas Klimpel
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Frank Andersohn
- Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin; Berlin Germany
- Frank Andersohn Consulting & Research Services; Berlin Germany
| | - Oliver Meyer
- Institute of Transfusion Medicine, Charité - Universitätsmedizin Berlin; Germany
| | - Abdulgabar Salama
- Institute of Transfusion Medicine, Charité - Universitätsmedizin Berlin; Germany
| | - Reinhold Kreutz
- Institute of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin; Berlin Germany
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20
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Abstract
Heparin-induced thrombocytopenia (HIT) is an immune complication of heparin therapy caused by antibodies to complexes of platelet factor 4 (PF4) and heparin. Pathogenic antibodies to PF4/heparin bind and activate cellular FcγRIIA on platelets and monocytes to propagate a hypercoagulable state culminating in life-threatening thrombosis. It is now recognized that anti-PF4/heparin antibodies develop commonly after heparin exposure, but only a subset of sensitized patients progress to life-threatening complications of thrombocytopenia and thrombosis. Recent scientific developments have clarified mechanisms underlying PF4/heparin immunogenicity, disease susceptibility, and clinical manifestations of disease. Insights from clinical and laboratory findings have also been recently harnessed for disease prevention. This review will summarize our current understanding of HIT by reviewing pathogenesis, essential clinical and laboratory features, and management.
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21
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Is low serum albumin level a significant predictor for the development of heparin-induced thrombocytopenia-thrombosis? Ann Hematol 2017; 96:1033-1036. [PMID: 28289828 DOI: 10.1007/s00277-017-2971-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 03/04/2017] [Indexed: 10/20/2022]
Abstract
The present study investigates the effect of albumin levels in patients who have developed heparin-induced thrombocytopenia (HIT) and heparin-induced thrombocytopenia-thrombosis (HITT). A retrospective observational cohort study was conducted at King Abudlaziz Medical City (KAMC), a university teaching hospital, on patients diagnosed with HIT between June 2013 and December 2014. Clinical and laboratory findings were used to confirm HIT. Albumin levels were reported on admission as baseline and during HIT occurrence. Twenty-eight patients were identified as HIT positive by enzyme-linked immunosorbent assay (ELISA), with a cutoff value of ≥1 optical density units and pretest probability "4Ts" score of ≥4. Of the 28 patients, nine (32%) developed HITT. Demographic characteristics of the patients who developed HIT and HITT were similar. The mean albumin level for patients who developed HITT was significantly lower than that for patients who developed HIT (p < 0.001). Our findings suggest that patients with low serum albumin levels are at greater risk of developing HITT. This finding awaits confirmation in larger prospective clinical trials.
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22
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Onwuemene O, Arepally GM. Heparin-induced thrombocytopenia: research and clinical updates. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2016; 2016:262-268. [PMID: 27913490 PMCID: PMC6142447 DOI: 10.1182/asheducation-2016.1.262] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Heparin-induced thrombocytopenia (HIT) remains an important diagnosis to consider in hospitalized patients developing thrombocytopenia. HIT is an immune-mediated prothrombotic disorder caused by antibodies to platelet factor 4 (PF4) and heparin. Recent basic scientific studies have advanced our understanding of disease pathogenesis through studies of the PF4/heparin structure, immune mechanisms, and cellular basis of thrombosis. Clinical advances have also occurred in areas of HIT prevention, description of disease variants, and diagnostic strategies. Emerging anticoagulants with the potential to change HIT treatment are evolving, although with limited data. This review will provide a current perspective on HIT pathogenesis, disease features, diagnostic strategies, and role of emerging therapies for the management of HIT.
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Affiliation(s)
- Oluwatoyosi Onwuemene
- Division of Hematology, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Gowthami M Arepally
- Division of Hematology, Department of Medicine, Duke University Medical Center, Durham, NC
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23
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Bakchoul T. An update on heparin-induced thrombocytopenia: diagnosis and management. Expert Opin Drug Saf 2016; 15:787-97. [DOI: 10.1517/14740338.2016.1165667] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Tamam Bakchoul
- Institute for Immunology and Transfusion Medicine, Universitätsmedizin Greifswald, Greifswald, Germany
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24
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Kerényi A, Beke Debreceni I, Oláh Z, Ilonczai P, Bereczky Z, Nagy B, Muszbek L, Kappelmayer J. Evaluation of flow cytometric HIT assays in relation to an IgG-Specific immunoassay and clinical outcome. CYTOMETRY PART B-CLINICAL CYTOMETRY 2016; 92:389-397. [PMID: 26860978 DOI: 10.1002/cyto.b.21362] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 01/06/2016] [Accepted: 02/01/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND Heparin-induced thrombocytopenia (HIT) is a severe side effect of heparin treatment caused by platelet activating IgG antibodies generated against the platelet factor 4 (PF4)-heparin complex. Thrombocytopenia and thrombosis are the leading clinical symptoms of HIT. METHODS The clinical pretest probability of HIT was evaluated by the 4T score system. Laboratory testing of HIT was performed by immunological detection of antibodies against PF4-heparin complex (EIA) and two functional assays. Heparin-dependent activation of donor platelets by patient plasma was detected by flow cytometry. Increased binding of Annexin-V to platelets and elevated number of platelet-derived microparticles (PMP) were the indicators of platelet activation. RESULTS EIA for IgG isotype HIT antibodies was performed in 405 suspected HIT patients. Based on negative EIA results, HIT was excluded in 365 (90%) of cases. In 40 patients with positive EIA test result functional tests were performed. Platelet activating antibodies were detected in 17 cases by Annexin V binding. PMP count analysis provided nearly identical results. The probability of a positive flow cytometric assay result was higher in patients with elevated antibody titer. 71% of patients with positive EIA and functional assay had thrombosis. CONCLUSIONS EIA is an important first line laboratory test in the diagnosis of HIT; however, HIT must be confirmed by a functional test. Annexin V binding and PMP assays using flow cytometry are functional HIT tests convenient in a clinical diagnostic laboratory. The positive results of functional assays may predict the onset of thrombosis. © 2016 International Clinical Cytometry Society.
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Affiliation(s)
- Adrienne Kerényi
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Hungary
| | - Ildikó Beke Debreceni
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Hungary
| | - Zsolt Oláh
- Department of Medicine, Faculty of Medicine, University of Debrecen, Hungary
| | - Péter Ilonczai
- Department of Medicine, Faculty of Medicine, University of Debrecen, Hungary
| | - Zsuzsanna Bereczky
- Division of Clinical Laboratory Science, Faculty of Medicine, University of Debrecen, Hungary
| | - Béla Nagy
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Hungary
| | - László Muszbek
- Division of Clinical Laboratory Science, Faculty of Medicine, University of Debrecen, Hungary
| | - János Kappelmayer
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Hungary
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25
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Laverdure F, Louvain-Quintard V, Kortchinsky T, Rezaiguïa-Delclaux S, Imbert A, Stéphan F. PF4-heparin antibodies during ECMO: incidence, course, and outcomes. Intensive Care Med 2016; 42:1082-3. [PMID: 26903478 DOI: 10.1007/s00134-016-4262-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2016] [Indexed: 11/25/2022]
Affiliation(s)
- Florent Laverdure
- Cardiothoracic Intensive Care Unit, Service de Réanimation Adulte, Hôpital Marie Lannelongue, 133 Avenue de la Résistance, 92350, Le Plessis Robinson, France
| | - Virginie Louvain-Quintard
- Hemostasis Laboratory, Hôpital Marie Lannelongue, 133 Avenue de la Résistance, 92350, Le Plessis Robinson, France
| | - Talna Kortchinsky
- Cardiothoracic Intensive Care Unit, Service de Réanimation Adulte, Hôpital Marie Lannelongue, 133 Avenue de la Résistance, 92350, Le Plessis Robinson, France
| | - Saïda Rezaiguïa-Delclaux
- Cardiothoracic Intensive Care Unit, Service de Réanimation Adulte, Hôpital Marie Lannelongue, 133 Avenue de la Résistance, 92350, Le Plessis Robinson, France
| | - Audrey Imbert
- Cardiothoracic Intensive Care Unit, Service de Réanimation Adulte, Hôpital Marie Lannelongue, 133 Avenue de la Résistance, 92350, Le Plessis Robinson, France
| | - François Stéphan
- Cardiothoracic Intensive Care Unit, Service de Réanimation Adulte, Hôpital Marie Lannelongue, 133 Avenue de la Résistance, 92350, Le Plessis Robinson, France.
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26
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Lu BY, Kudlowitz D, Gardner LB. Clinical and laboratory characteristics associated with a high optical density anti-platelet factor 4 ELISA test. J Blood Med 2015; 6:277-83. [PMID: 26640392 PMCID: PMC4657791 DOI: 10.2147/jbm.s90179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Diagnosing heparin-induced thrombocytopenia, a potentially catastrophic immune-mediated disorder, continues to pose significant challenges for clinicians, as both clinical and laboratory tools lack specificity. There is mounting evidence supporting a positive correlation between definitive heparin-induced thrombocytopenia and optical density (OD) positivity from the widely available anti-platelet factor 4 enzyme-linked immunosorbent assays (PF4 ELISAs). However, the clinical features distinguishing these patients remain poorly understood. PATIENTS AND METHODS To better characterize this group, we conducted a case-controlled, retrospective chart review of patients from two large, urban academic institutions who underwent a PF4 ELISA at a central laboratory. Associations between OD and 18 clinical characteristics were calculated using the Fisher's exact test for categorical variables and Wilcoxon rank-sum test for continuous variables. RESULTS In total, 184 negative patients (OD <0.7), and 121 positive patients (OD >0.7), including 74 low-positive patients (0.7< OD <1.4) and 47 high-positive patients (OD >1.4) were identified. Several clinical variables were significantly different in the negative group compared with the positive group, including hospital day (P<0.001), previous admission within the past 3 months (P<0.001), and the presence of a new thrombus (P=0.003). However, many of these variables were not different between the negative and low-positive group, and were only distinct between the negative and high-positive group. When the low-positive and high-positive groups were compared, only the 4T score was significantly different (P=0.003). CONCLUSION These data indicate that those with OD >1.4 form a distinct clinical group and support the clinical utility of the 4T score.
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Affiliation(s)
- Benjamin Y Lu
- Department of Medicine, NYU School of Medicine, New York, NY, USA
| | - David Kudlowitz
- Department of Medicine, NYU School of Medicine, New York, NY, USA
| | - Lawrence B Gardner
- Department of Medicine, NYU School of Medicine, New York, NY, USA ; Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, NY, USA ; The Perlmutter Cancer Center, NYU Langone Medical Center, NYU School of Medicine, New York, NY, USA
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Chan CM, Woods CJ, Warkentin TE, Sheppard JAI, Shorr AF. The Role for Optical Density in Heparin-Induced Thrombocytopenia. Chest 2015; 148:55-61. [DOI: 10.1378/chest.14-1417] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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28
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Warkentin TE, Arnold DM, Nazi I, Kelton JG. The platelet serotonin-release assay. Am J Hematol 2015; 90:564-72. [PMID: 25775976 DOI: 10.1002/ajh.24006] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/05/2015] [Accepted: 03/08/2015] [Indexed: 12/24/2022]
Abstract
Few laboratory tests are as clinically useful as The platelet serotonin-release assay (SRA): a positive SRA in the appropriate clinical context is virtually diagnostic of heparin-induced thrombocytopenia (HIT), a life- and limb-threatening prothrombotic disorder caused by anti-platelet factor 4 (PF4)/heparin antibodies that activate platelets, thereby triggering serotonin-release. The SRA's performance characteristics include high sensitivity and specificity, although caveats include indeterminate reaction profiles (observed in ∼4% of test sera) and potential for false-positive reactions. As only a subset of anti-PF4/heparin antibodies detectable by enzyme-immunoassay (EIA) are additionally platelet-activating, the SRA has far greater diagnostic specificity than the EIA. However, requiring a positive EIA, either as an initial screening test or as an SRA adjunct, will reduce risk of a false-positive SRA (since a negative EIA in a patient with a "positive" SRA should prompt critical evaluation of the SRA reaction profile). The SRA also provides useful information on whether a HIT serum produces strong platelet activation even in the absence of heparin: such heparin-"independent" platelet activation is a marker of unusually severe HIT, including delayed-onset HIT and severe HIT complicated by consumptive coagulopathy with risk for microvascular thrombosis.
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Affiliation(s)
- Theodore E. Warkentin
- Department of Pathology and Molecular Medicine; Michael G. DeGroote School of Medicine; McMaster University; Hamilton Ontario Canada
- Department of Medicine; Michael G. DeGroote School of Medicine; McMaster University; Hamilton Ontario Canada
| | - Donald M. Arnold
- Department of Medicine; Michael G. DeGroote School of Medicine; McMaster University; Hamilton Ontario Canada
| | - Ishac Nazi
- Department of Medicine; Michael G. DeGroote School of Medicine; McMaster University; Hamilton Ontario Canada
| | - John G. Kelton
- Department of Pathology and Molecular Medicine; Michael G. DeGroote School of Medicine; McMaster University; Hamilton Ontario Canada
- Department of Medicine; Michael G. DeGroote School of Medicine; McMaster University; Hamilton Ontario Canada
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Medication Use Evaluation: Pharmacist Rubric for Performance Improvement. Pharmacotherapy 2014; 34 Suppl 1:5S-13S. [DOI: 10.1002/phar.1506] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Tapan U, Bolla S, Daglilar ES, Chang S, Kozyreva O. Outcome of patients with positive heparin–platelet factor-4 antibodies: A retrospective multi-institutional observational study. Platelets 2014; 26:661-4. [DOI: 10.3109/09537104.2014.977243] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Gruel Y, Rollin J, Leroux D, Pouplard C. Les thrombocytopénies induites par l’héparine : données récentes. Rev Med Interne 2014; 35:174-82. [DOI: 10.1016/j.revmed.2013.04.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Revised: 04/23/2013] [Accepted: 04/27/2013] [Indexed: 01/08/2023]
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de Prada Martín B, Gualis Cardona J, Pérez Blanco I, Martínez Comendador JM. [Fulminant coagulopathy after bivalirudin use in a patient diagnosed with heparin-induced thrombocytopenia and subject to cardiac bypass surgery]. REVISTA ESPANOLA DE ANESTESIOLOGIA Y REANIMACION 2014; 61:157-161. [PMID: 23601838 DOI: 10.1016/j.redar.2013.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Revised: 01/18/2013] [Accepted: 01/24/2013] [Indexed: 06/02/2023]
Abstract
Patients with a previous history of heparin-induced thrombocytopenia are at a higher risk for thromboembolic events, and heparin administration is formally contraindicated. Bivalirudin has been reported as an alternative therapy whenever an intervention that requires systemic anticoagulation and cardiopulmonary by-pass pump is needed. We present the case of a patient diagnosed with heparin-induced thrombocytopenia and heparin-PF4 (+) antibodies requiring a triple cardiac valve replacement who developed fulminant coagulopathy after bivalirudin administration. A discussion on the serious difficulties that the management of these types of patients involves, as well as a review of prevention strategies are presented.
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Affiliation(s)
- B de Prada Martín
- Servicio de Anestesiología, Reanimación y Tratamiento del Dolor, Complejo Hospitalario de León, León, España.
| | - J Gualis Cardona
- Servicio de Cirugía Cardiovascular, Complejo Hospitalario de León, León, España
| | - I Pérez Blanco
- Servicio de Anestesiología, Reanimación y Tratamiento del Dolor, Complejo Hospitalario de León, León, España
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Platelet factor 4/heparin-particle gel immunoassay (PaGIA) is a weak method for heparin-induced thrombocytopenia (HIT) evaluation of post cardio-pulmonary bypass surgery patients. J Thromb Thrombolysis 2014; 38:314-20. [DOI: 10.1007/s11239-014-1066-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Pearson MA, Nadeau C, Blais N. Correlation of ELISA Optical Density With Clinical Diagnosis of Heparin-Induced Thrombocytopenia. Clin Appl Thromb Hemost 2013; 20:349-54. [DOI: 10.1177/1076029613513319] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: Enzyme-linked immunosorbent assay (ELISA) for antiplatelet factor 4 (anti-PF4)/heparin antibodies is expressed in terms of optical density (OD). Previous studies have shown correlation between OD and heparin-induced thrombocytopenia (HIT) diagnosis. However, these were mainly laboratory based. Objective: Retrospective correlation of clinical HIT to ELISA OD. Patients/Methods: We conducted a retrospective study involving 104 patients with a positive ELISA for anti-PF4/heparin antibodies between 2008 and May 2012. For each patient, a clinical diagnosis was adjudicated based on different features including “4T scores,” laboratory results, and a 3-month clinical follow-up. Results: In this study, 28.8% of the patients were HIT positive, and 71.2% HIT negative. Patients with positive diagnosis had significantly higher mean OD (2.15 ± 0.76 vs 0.83 ± 0.62). Patients with OD <1.0 only had 3.4% positive diagnosis versus 45.5% for OD 1.0 to 2.0 and 78% for >2.0 units. Conclusion: This study is a clinical confirmation that ELISA OD results are correlated with the probability of a clinical diagnosis of HIT.
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Affiliation(s)
- Marc-André Pearson
- Department of Hematology-Oncology, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Chantal Nadeau
- Haemostasis Laboratory, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Normand Blais
- Department of Hematology-Transfusion Medicine, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
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Raschke RA, Curry SC, Warkentin TE, Gerkin RD. Improving Clinical Interpretation of the Anti-Platelet Factor 4/Heparin Enzyme-Linked Immunosorbent Assay for the Diagnosis of Heparin-Induced Thrombocytopenia Through the Use of Receiver Operating Characteristic Analysis, Stratum-Specific Likelihood Ratios, and Bayes Theorem. Chest 2013; 144:1269-1275. [DOI: 10.1378/chest.12-2712] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Refractoriness to platelet transfusion in acute myeloid leukemia correlated with the optical density of anti-platelet factor 4/heparin antibodies. Int J Hematol 2013; 98:472-7. [DOI: 10.1007/s12185-013-1427-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 08/30/2013] [Accepted: 09/02/2013] [Indexed: 12/28/2022]
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Lee GM, Arepally GM. Diagnosis and management of heparin-induced thrombocytopenia. Hematol Oncol Clin North Am 2013; 27:541-63. [PMID: 23714311 DOI: 10.1016/j.hoc.2013.02.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder caused by antibodies to platelet factor 4/heparin (PF4/H) complexes. It presents with declining platelet counts 5 to 14 days after heparin administration and results in a predisposition to arterial and venous thrombosis. Establishing the diagnosis of HIT can be extremely challenging. It is essential to conduct a thorough clinical evaluation in addition to laboratory testing to confirm the presence of PF4/H antibodies. Multiple clinical algorithms have been developed to aid the clinician in predicting the likelihood of HIT. Once HIT is recognized, an alternative anticoagulant should be initiated to prevent further complications.
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Affiliation(s)
- Grace M Lee
- Division of Hematology, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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Hassan S, Qureshi W, Badami A, Khoulani D, Mittal C, Amer S, Alirhayim Z, Kuriakose P. Heparin-induced thrombocytopenia: is it a graft-threatening complication? Transpl Int 2013; 26:385-91. [PMID: 23293891 DOI: 10.1111/tri.12051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Revised: 10/30/2012] [Accepted: 12/07/2012] [Indexed: 12/11/2022]
Abstract
Heparin-induced thrombocytopenia (HIT), a prothrombotic complication of heparin therapy, can lead to serious thromboembolic events and cause significant morbidity and mortality. We aim to study the prevalence of HIT in the transplant population at our institute. This is a retrospective, single-center study which looked into the transplant database over a 25-year period. In patients with clinical suspicion of HIT, the 4T score was used, and laboratory tests such as ELISA HIT antibody and functional serotonin release assay, along with clinical manifestation of thromboembolic events were reviewed. Medical records of 2800 patients who underwent transplantation from January 1985 to December 2010 were reviewed. HIT antibody assay was performed in 262 patients from this group in which HIT was suspected. Of these, only 48 patients were HIT antibody positive along with moderate to high 4T score. The mean 4T score was 6.75 ± 1.4. Thrombotic complications were seen in 11 patients, with the highest in cardiac transplant recipients. Direct thrombin inhibitor (DTI) therapy was used in only eight patients who had thrombotic event. No other complications or mortality was reported in any of the HIT antibody-positive transplant patients. To our knowledge, this is the first study of its kind that has shown very low incidence of HIT in the transplant population except for in cardiac transplant recipients.
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Affiliation(s)
- Syed Hassan
- Department of Internal Medicine, Henry Ford Hospital, Detroit, MI 48202, USA.
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Lee GM, Arepally GM. Heparin-induced thrombocytopenia. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2013; 2013:668-74. [PMID: 24319250 PMCID: PMC4153428 DOI: 10.1182/asheducation-2013.1.668] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder caused by antibodies that recognize complexes of platelet factor 4 (PF4) and heparin. HIT is frequently considered in the differential diagnosis of thrombocytopenia occurring in patients on heparin therapy. HIT is a challenging diagnosis because of routine heparin use in hospitalized patients, the common occurrence of thrombocytopenia, and high rates of anti-PF4/heparin seroconversions in patients treated with heparin. Our diagnostic approach to HIT is presented here, underscoring critical elements of clinical and laboratory evaluation.
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Affiliation(s)
- Grace M. Lee
- Hematology/Oncology Fellow, Division of Hematology, Department of Medicine, DUMC Box 3841, Duke University Medical Center, Room 301 Sands Building, Durham, NC 27710, Phone: 919-668-1550, Fax: 919-684-2420
| | - Gowthami M. Arepally
- Associate Professor, Medicine, Division of Hematology, Department of Medicine, Duke University Medical Center, DUMC Box 3486, Room 301 Sands Building, Durham, NC 27710, Phone: 919-668-1550, Fax: 919-684-2420
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Abstract
Thrombocytopenia is common in critically ill patients and increases morbidity and mortality. A diagnosis of heparin-induced thrombocytopenia (HIT) is frequently considered in any ICU patient who develops thrombocytopenia in the context of ongoing heparin exposure. As the usual tests to diagnose HIT are often neither specific nor sensitive enough to be confirmatory, the intensivist must largely rely on clinical judgment in treatment decisions. Patients in the ICU may also develop thrombocytopenia resulting from non-HIT immune mechanisms, nonimmune platelet consumption, and from decreased platelet production due to preexisting disorders or as a result of their critical illness and/or drug therapy.
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Affiliation(s)
- Robert I Parker
- Department of Pediatrics, Stony Brook University School of Medicine, Pediatric Hematology/Oncology, Stony Brook Long Island Children's Hospital, Stony Brook, NY 11794-8111, USA.
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Warkentin TE. Optical densities reduce odds of heparin-induced thrombocytopenia over-diagnosis. Am J Med 2012; 125:3-4. [PMID: 22195526 DOI: 10.1016/j.amjmed.2011.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 10/06/2011] [Accepted: 10/06/2011] [Indexed: 11/29/2022]
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