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Saadalla A, Chen D, Stuart M, Pruthi R, Heikal N, Snyder M, Ashrani A, Seheult J. The lupus anticoagulant titer is associated with elevated antiphosphatidylserine/prothrombin immunoglobulin-M isotype antibody levels. Int J Lab Hematol 2024; 46:695-704. [PMID: 38380742 DOI: 10.1111/ijlh.14251] [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: 09/04/2023] [Accepted: 02/04/2024] [Indexed: 02/22/2024]
Abstract
BACKGROUND Clot based assays used for lupus anticoagulant (LAC) detection are typically interpreted in a qualitative fashion and may not reflect LAC potency. In this cross-sectional study, we describe a method for quantifying the LAC titer using serial (dependent) two-fold dilutions in normal pooled plasma. METHODS Serial dilutions of 51 residual plasma samples from 50 patients were tested using the Russell's viper venom screening time (DRVVT) and activated partial thromboplastin screening time (APTT) methodologies. The measured clotting times and the corresponding dilution factors were then used to derive a four-parameter logistic model. The LAC titer for each patient was interpolated as the sample dilution that corresponds to the upper reference interval limit of the corresponding assay. RESULTS Calculated APTT and DRVVT LAC titers displayed a strong linear correlation (R2 = 0.84) between each other, but not with the degree of prolongation of the APTT/DRVVT screening time in the neat undiluted samples. Using data driven partitioning, patients could be grouped into low (<10) or high (≥10) DRVVT LAC titer. There were no significant differences in anticardiolipin (aCL) or anti-beta 2 glycoprotein 1 (aB2GPI) antibody levels or prevalence of thromboembolic events between low and high LAC titer groups. In contrast, antiphosphatidylserine/prothrombin (aPS/PT) IgM antibody levels, but not IgG, were significantly higher in the high LAC titer group. CONCLUSIONS The degree of prolongation of the APTT/DRVVT screening time is not correlated with the LAC titer. Only aPS/PT IgM antibodies levels were strongly correlated with the LAC titers. Additional studies are warranted to determine clinical implications of high LAC titers.
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Affiliation(s)
- Abdulrahman Saadalla
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
- ARUP Laboratories, Salt Lake City, Utah, USA
| | - Dong Chen
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Melissa Stuart
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Rajiv Pruthi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Nahla Heikal
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Melissa Snyder
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Aneel Ashrani
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Jansen Seheult
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
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Ding Z, Pan H, Yang Z, Yang C, Shi H. Beyond the classics: The emerging value of anti-phosphatidylserine/prothrombin antibodies in antiphospholipid syndrome. Clin Immunol 2023; 256:109804. [PMID: 37838215 DOI: 10.1016/j.clim.2023.109804] [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: 06/27/2023] [Revised: 09/24/2023] [Accepted: 10/05/2023] [Indexed: 10/16/2023]
Abstract
Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by the presence of antiphospholipid antibodies (aPLs), which can lead to thrombosis and pregnancy complications. Within the diverse range of aPLs, anti-phosphatidylserine/prothrombin antibodies (aPS/PT) have gained significance in clinical practice. The detection of aPS/PT has proven valuable in identifying APS patients and stratifying their risk, especially when combined with other aPL tests like lupus anticoagulant (LA) and anti-β2-glycoprotein I (aβ2GPI). Multivariate analyses have confirmed aPS/PT as an independent risk factor for vascular thrombosis and obstetric complications, with its inclusion in the aPL score and the Global Anti-Phospholipid Syndrome Score (GAPSS) aiding in risk evaluation. However, challenges remain in the laboratory testing of aPS/PT, including the need for assay standardization and its lower sensitivity in certain patient populations. Further research is necessary to validate the clinical utility of aPS/PT antibodies in APS diagnosis, risk stratification, and management.
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Affiliation(s)
- Zetao Ding
- Department of Rheumatology and Immunology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Haoyu Pan
- Department of Rheumatology and Immunology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhixia Yang
- Department of Rheumatology and Immunology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Chengde Yang
- Department of Rheumatology and Immunology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Hui Shi
- Department of Rheumatology and Immunology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
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Suenaga A, Sawa N, Oshima Y, Ikuma D, Oba Y, Yamanouchi M, Hasegawa E, Mizuno H, Sekine A, Suwabe T, Kono K, Kinowaki K, Ohashi K, Takemura T, Yamaguchi Y, Miyazono M, Atsumi T, Ubara Y. Antiphospholipid Syndrome Nephropathy Related Disease Diagnosed by Assessing Phosphatidylserine-dependent Antiprothrombin Antibodies. Intern Med 2023; 62:757-761. [PMID: 35908966 PMCID: PMC10037018 DOI: 10.2169/internalmedicine.0302-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 42-year-old Japanese woman was admitted for the evaluation of proteinuria. She had a history of four habitual abortions and valvular heart disease, including severe mitral regurgitation and moderate tricuspid regurgitation. A kidney biopsy showed fibrointimal thickening of interlobular arteries, fibrin thrombosis, and associated focal segmental sclerosis. Although the standard test for antiphospholipid (aPL) antibodies was negative, the patient was diagnosed with antiphospholipid syndrome (APS)-related disease by testing for phosphatidylserine dependent anti-prothrombin anticardiolipin antibody, a non-criterial aPL antibody. A kidney biopsy may lead to a diagnosis of APS in patients with negative laboratory test findings for APS.
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Affiliation(s)
- Atsuhiko Suenaga
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
- Department of Nephrology, Saga University School of Medicine, Japan
| | - Naoki Sawa
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Yoichi Oshima
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Nephrology, Keio University School of Medicine, Japan
| | - Daisuke Ikuma
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Yuki Oba
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Masayuki Yamanouchi
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Eiko Hasegawa
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Nephrology, Keio University School of Medicine, Japan
| | - Hiroki Mizuno
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Akinari Sekine
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Tatsuya Suwabe
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
| | - Kei Kono
- Department of Pathology, Toranomon Hospital, Japan
| | | | - Kenichi Ohashi
- Department of Pathology, Toranomon Hospital, Japan
- Department of Human Pathology, Tokyo Medical Dental University, Japan
| | - Tamiko Takemura
- Department of Pathology, Kanagawa Cardiovascular and Respiratory Center, Japan
| | | | - Motoaki Miyazono
- Department of Nephrology, Saga University School of Medicine, Japan
| | - Tatsuya Atsumi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine, Hokkaido University, Japan
| | - Yoshifumi Ubara
- Department of Nephrology and Rheumatology and Okinaka Memorial Institute for Medical Research, Toranomon Hospital, Japan
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Estévez MÁ, Lanio N, Molina Á, Jiménez-León MR, Picado MJ, Esteban E, Sánchez S, Pallarés L, Julià MR. Extra-criteria antiphospholipid antibodies in patients with small vessel brain lesions and clinical manifestations associated with antiphospholipid syndrome. J Stroke Cerebrovasc Dis 2023; 32:107034. [PMID: 36842350 DOI: 10.1016/j.jstrokecerebrovasdis.2023.107034] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/27/2023] Open
Abstract
OBJECTIVES Neurological manifestations compatible with small vessel brain lesions (SVBL), such as migraine, cognitive impairment, seizures, and transverse myelitis, may be related to antiphospholipid syndrome (APS) and patients could need APS therapies even though they do not fit into thrombosis or obstetric morbidity. Furthermore, extra-criteria antiphospholipid antibodies (aPL) provide an increase in sensitivity in patients with clinical manifestations related to APS but negative for IgG/IgM anticardiolipin (aCL), anti-β2 glycoprotein I (aβ2GPI), and lupus anticoagulant, which are the antibodies included in the classification criteria for APS. METHODS We determined extra-criteria aPL in 65 SVBL patients with neurological traits and Magnetic Resonance Imaging suggestive of APS but negative for APS classification criteria, 47 of whom were prospectively followed and tested over three years. A group of 95 patients with autoimmune diseases (AD) but without clinical traits of APS was also studied. RESULTS A persistent presence of extra-criteria aPL was detected in 27.7% of patients: 12.77% IgM anti- prothrombin (PT), 6.38% IgG anti-PT, 6.38% IgM anti-phosphatidylethanolamine (PE), 4.26% IgA aβ2GPI, 2.13% IgG anti-phosphatidylserine/prothrombin (PS/PT) and 2.13% IgM anti-PS/PT. There was a tendency towards a higher prevalence of these aPL in SVBL patients than in AD - especially for IgA aβ2GPI - and a lack of IgG aPS/PT positivity in the AD group. We found no SVBL patient positive for IgA aCL, IgG anti-PE, annexin V, or aβ2GPI domain I. CONCLUSIONS Extra-criteria aPL can improve sensitivity for APS diagnosis in patients with SVBL, especially IgA aβ2GPI and IgG anti-PS/PT antibodies.
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Affiliation(s)
- Miguel Ángel Estévez
- Immunology Department, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - Nallibe Lanio
- Immunology Department, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - Águeda Molina
- Immunology Department, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - Maria Reyes Jiménez-León
- Immunology Department, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - María José Picado
- Radiology Department, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - Eva Esteban
- Systemic Autoimmune Diseases Unit, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - Sonia Sánchez
- Systemic Autoimmune Diseases Unit, Hospital Fundación Alcorcón, Madrid, Spain
| | - Lucio Pallarés
- Systemic Autoimmune Diseases Unit, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain
| | - Maria Rosa Julià
- Immunology Department, Hospital Universitari Son Espases, Institut d'Investigació Sanitària Illes Balears (IdISBa), 07010, Palma de Mallorca, Balearic Islands, Spain.
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Pignatelli P, Ettorre E, Menichelli D, Pani A, Violi F, Pastori D. Seronegative antiphospholipid syndrome: refining the value of "non-criteria" antibodies for diagnosis and clinical management. Haematologica 2020; 105:562-572. [PMID: 32001534 PMCID: PMC7049333 DOI: 10.3324/haematol.2019.221945] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 12/18/2019] [Indexed: 11/16/2022] Open
Abstract
Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by arterial and venous thrombotic manifestations and/or pregnancy-related complications in patients with persistently high antiphospholipid antibodies (aPL), the most common being represented by anticardiolipin antibodies (aCL), anti-beta 2 glycoprotein-I (aβ2GPI), and lupus anticoagulant (LAC). A growing number of studies have showed that, in some cases, patients may present with clinical features of APS but with temporary positive or persistently negative titers of aPL. For these patients, the definition of seronegative APS (SN-APS) has been proposed. Nevertheless, the negativity to classic aPL criteria does not imply that other antibodies may be present or involved in the onset of thrombosis. The diagnosis of SN-APS is usually made by exclusion, but its recognition is important to adopt the most appropriate anti-thrombotic strategy to reduce the rate of recurrences. This research is in continuous development as the clinical relevance of these antibodies is far from being completely clarified. The most studied antibodies are those against phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, phosphatidylinositol, vimentin/cardiolipin complex, and annexin A5. Moreover, the assays to measure the levels of these antibodies have not yet been standardized. In this review, we will summarize the evidence on the most studied non-criteria aPL, their potential clinical relevance, and the antithrombotic therapeutic strategies available in the setting of APS and SN-APS.
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Affiliation(s)
- Pasquale Pignatelli
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome.,Mediterranea Cardiocentro, Naples
| | - Evaristo Ettorre
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Division of Gerontology, Sapienza University, Rome
| | - Danilo Menichelli
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome
| | - Arianna Pani
- Department of Oncology and Onco-Hematology, University of Milan, Milan.,Clinical Pharmacology Unit, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Francesco Violi
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome.,Mediterranea Cardiocentro, Naples
| | - Daniele Pastori
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome
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7
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Heikal N, Martins TB, White SK, Willis R, Ware Branch D, Schmidt RL, Tebo AE. Laboratory Evaluation of Antiphospholipid Syndrome. Am J Clin Pathol 2019; 152:638-646. [PMID: 31305881 DOI: 10.1093/ajcp/aqz085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Anti-β2 glycoprotein I domain I (anti-domain I) and anti-phosphatidylserine/prothrombin (aPS/PT) antibodies are present in patients with antiphospholipid syndrome (APS); however, their use in evaluation remains unclear. METHODS Diagnostic attributes of lupus anticoagulant (LAC), anti-domain I IgG, anti-cardiolipin, anti-β2 glycoprotein I (anti-β2GPI), and aPS/PT IgG and IgM antibodies were assessed in 216 patients evaluated for APS. RESULTS LAC had the best odds ratio (OR, 14.2) while that for anti-domain 1 IgG was comparable to anti-β2GPI IgG (OR, 8.3 vs 9.4) but higher than all others. Significant correlations were observed for thrombosis (P = .03) and pregnancy-related morbidity (P = .001) with anti-domain IgG and for any thrombosis with aPS/PT IgG (P = .006). Use of noncriteria antiphospholipid with or without criteria markers did not significantly increase the probability to diagnose APS. CONCLUSIONS Noncriteria tests can contribute to diagnosis and stratification of APS but do not improve diagnostic yield. Optimal strategies for implementation require prospective investigation.
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Affiliation(s)
- Nahla Heikal
- ARUP Institute of Clinical and Experimental Pathology, University of Utah School of Medicine, Salt Lake City
- Department of Pathology, University of Utah School of Medicine, Salt Lake City
| | - Thomas B Martins
- ARUP Institute of Clinical and Experimental Pathology, University of Utah School of Medicine, Salt Lake City
| | - Sandra K White
- Department of Pathology, University of Utah School of Medicine, Salt Lake City
| | - Rohan Willis
- Division of Rheumatology, Department of Internal Medicine, University of Texas Medical Branch, Galveston
| | - D Ware Branch
- Division of Maternal-Fetal Medicine, University of Utah School of Medicine, Salt Lake City
- Intermountain Healthcare, Salt Lake City, UT
| | - Robert L Schmidt
- ARUP Institute of Clinical and Experimental Pathology, University of Utah School of Medicine, Salt Lake City
- Department of Pathology, University of Utah School of Medicine, Salt Lake City
| | - Anne E Tebo
- ARUP Institute of Clinical and Experimental Pathology, University of Utah School of Medicine, Salt Lake City
- Department of Pathology, University of Utah School of Medicine, Salt Lake City
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8
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Ząbczyk M, Celińska-Löwenhoff M, Plens K, Iwaniec T, Musiał J, Undas A. Antiphosphatidylserine/prothrombin complex antibodies as a determinant of prothrombotic plasma fibrin clot properties in patients with antiphospholipid syndrome. J Thromb Haemost 2019; 17:1746-1755. [PMID: 31220407 DOI: 10.1111/jth.14551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/30/2019] [Accepted: 06/14/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND Antiphosphatidylserine/prothrombin complex (aPS/PT) antibodies are recognized as a marker for antiphospholipid syndrome (APS). Dense and poorly lysable fibrin clots occur in thrombotic APS. Compact clots predict thromboembolism, but determinants of the unfavorable clot phenotype remain unknown in APS. We hypothesized that elevated aPS/PT antibodies determine unfavorable clot features. METHODS In a cohort study involving 124 consecutive patients with thrombotic APS, we measured at baseline plasma fibrin clot permeability (Ks ), efficiency of fibrinolysis (clot lysis time, CLT), and turbidity (off anticoagulation) along with immunoglobulin (Ig)G/IgM aPS/PT. During follow-up, symptomatic thromboembolic events were recorded. RESULTS Elevated IgG and IgM aPS/PT antibodies >30 international enzyme units (UI) were detected in 54.8% and 42.7% of APS patients, including 76.2% and 54% of lupus anticoagulant- (LA, n = 63) positive patients, respectively. Elevated IgG and IgM aPS/PT antibodies predicted low Ks (lower quartile, <6 × 10-9 cm2 ; odds ratio [OR] = 5.93, 95% confidence interval [CI] 2.09-16.82 and OR = 11.79, 95% CI 4.10-33.92) and prolonged CLT (top quartile, ≥116 min; OR = 4.85, 95% CI 2.42-25.07 and OR = 6.04, 95% CI 2.42-15.07). No such associations were observed for anticardiolipin or β2-glycoprotein I antibodies or LA presence. During follow-up (median 72.5, range 66-83 months), thromboembolic events observed in 32 (26.7%, 4.6%/year) patients were independently predicted by IgG aPS/PT antibodies >30 UI (hazard ratio [HR] = 3.04, 95% CI 1.20-8.88) and low Ks (HR = 3.00, 95% CI 1.41-6.50). CONCLUSIONS We identified aPS/PT antibodies as a determinant of denser and poorly lysable plasma fibrin clot formation in APS patients. The association of elevated aPS/PT antibodies with thromboembolism in APS could be at least in part mediated by prothrombotic clot properties.
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Affiliation(s)
- Michał Ząbczyk
- Institute of Cardiology, Jagiellonian University Medical College and John Paul II Hospital, Krakow, Poland
| | | | | | - Teresa Iwaniec
- Department of Medicine, Jagiellonian University Medical College, Krakow, Poland
| | - Jacek Musiał
- Department of Medicine, Jagiellonian University Medical College, Krakow, Poland
| | - Anetta Undas
- Institute of Cardiology, Jagiellonian University Medical College and John Paul II Hospital, Krakow, Poland
- Faculty of Medicine and Health Sciences, Jan Kochanowski University, Kielce, Poland
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Núñez-Álvarez CA, Hernández-Molina G, Bermúdez-Bermejo P, Zamora-Legoff V, Hernández-Ramírez DF, Olivares-Martínez E, Cabral AR. Prevalence and associations of anti-phosphatidylserine/prothrombin antibodies with clinical phenotypes in patients with primary antiphospholipid syndrome: aPS/PT antibodies in primary antiphospholipid syndrome. Thromb Res 2018; 174:141-147. [PMID: 30612005 DOI: 10.1016/j.thromres.2018.12.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 11/24/2018] [Accepted: 12/27/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The clinical significance of anti-phosphatidylserine/prothrombin (aPS/PT) in antiphospholipid syndrome (APS) is still controversial. We assessed the prevalence of aPS/PT antibodies, their association with other anti-phospholipid antibodies (aPL) and with different APS clinical phenotypes. METHODS We included 95 primary APS patients according to the Sydney classification criteria, and patients with thrombocytopenia and/or hemolytic anemia who also fulfilled the serological APS criteria. We tested aCL, anti-β2GP-I and aPS/PT antibodies (both IgG and IgM isotypes) and lupus anticoagulant (LA). We used χ2 test, Spearman's correlation coefficient, Mann-Whitney U test and logistic regression. RESULTS Seventy-seven percent of patients had thrombosis, 50% hematologic involvement and 25% obstetric events (non-exclusive groups). Twenty patients had only hematologic features. The prevalence of IgG and IgM aPS/PT antibodies was 61% and 60%, respectively. Patients with LA+ had a higher prevalence and higher titers of IgG and IgM aPS/PT antibodies. aPS/PT antibodies correlated with aPL antibodies including LA. IgG aPS/PT antibodies were associated with thrombosis (OR 8.6 [95% CI 2.13-33.8, p = 0.002]) and pure hematologic features (OR 0.2, CI 95% 0.05-0.97, p = 0.004). IgM anti-β2GP-I antibodies conferred high risk for both hematologic (OR 7.9, 95% CI 1.88-34.61, p = 0.006) and thrombotic involvement (OR 7.4, 95% CI 1.76-31.12, p = 0.006). CONCLUSIONS aPS/PT antibodies were highly prevalent and correlated with other aPL antibodies. IgG aPTS/PT conferred a high risk for thrombosis, but not for pure hematologic involvement. aPS/PT antibodies may be a useful serological tool in the diagnosis and phenotypic characterization of APS patients.
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Affiliation(s)
- Carlos A Núñez-Álvarez
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15. Col. Sección XVI Belisario Domínguez, CP 14080 Mexico City, Mexico
| | - Gabriela Hernández-Molina
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15. Col. Sección XVI Belisario Domínguez, CP 14080 Mexico City, Mexico
| | - Paola Bermúdez-Bermejo
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15. Col. Sección XVI Belisario Domínguez, CP 14080 Mexico City, Mexico
| | - Victor Zamora-Legoff
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15. Col. Sección XVI Belisario Domínguez, CP 14080 Mexico City, Mexico
| | - Diego F Hernández-Ramírez
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15. Col. Sección XVI Belisario Domínguez, CP 14080 Mexico City, Mexico
| | - Elizabeth Olivares-Martínez
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15. Col. Sección XVI Belisario Domínguez, CP 14080 Mexico City, Mexico
| | - Antonio R Cabral
- Department of Medicine, Division of Rheumatology, The Ottawa Hospital, University of Ottawa, 1967 Riverside Drive, K1H 7W9 Ottawa, ON, Canada.
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10
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Study of clinical utility of antibodies to phosphatidylserine/prothrombin complex in Asian-Indian patients with suspected APS. Clin Rheumatol 2018; 38:545-553. [DOI: 10.1007/s10067-018-4301-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/09/2018] [Accepted: 09/14/2018] [Indexed: 10/28/2022]
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11
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Immunoproteomic identification of anti-C9 autoimmune antibody in patients with seronegative obstetric antiphospholipid syndrome. PLoS One 2018; 13:e0198472. [PMID: 29894483 PMCID: PMC5997311 DOI: 10.1371/journal.pone.0198472] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/18/2018] [Indexed: 01/24/2023] Open
Abstract
Immunoproteomic analysis was performed to identify unknown, pathology-related molecules in patients with seronegative (SN) obstetric antiphospholipid syndrome (APS) who clinically satisfied the diagnostic criteria for APS, but not the serological criteria. We collected peripheral blood from 13 SN-APS outpatients with known thrombotic predisposition, 13 with no known thrombotic predisposition, and four multiparous women with no history of miscarriage (control). Plasma proteins from volunteers were purified and used as plasma protein antigens. Two-dimensional immunoblotting was performed using pooled control or SN-APS serum samples as the primary antibodies. Mass spectrometry of reactive spots specific to SN-APS serum led to the identification of complement molecule C9. Western blotting using commercial purified alkylated C9 was performed to detect autoantibodies. Examination of individual patient serum identified reactivity in one patient with, and in two patients without known thrombotic predisposition. This study suggests that SN-APS pathologies were associated with autoantibodies that react to specific C9 epitopes.
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Oku K, Amengual O, Yasuda S, Atsumi T. How to Identify High-Risk APS Patients: Clinical Utility and Predictive Values of Validated Scores. Curr Rheumatol Rep 2018; 19:51. [PMID: 28741233 DOI: 10.1007/s11926-017-0674-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW Antiphospholipid syndrome (APS) is a clinical disorder characterised by thrombosis and/or pregnancy morbidity in the persistence of antiphospholipid (aPL) antibodies that are pathogenic and have pro-coagulant activities. Thrombosis in APS tends to recur and require prophylaxis; however, the stereotypical treatment for APS patients is inadequate and stratification of the thrombotic risks is important as aPL are prevalently observed in various diseases or elderly population. RECENT FINDINGS It is previously known that the multiple positive aPL or high titre aPL correlate to thrombotic events. To progress the stratification of thrombotic risks in APS patients and to quantitatively analyse those risks, antiphospholipid score (aPL-S) and the Global Anti-phospholipid Syndrome Score (GAPSS) were defined. These scores were raised from the large patient cohort data and either aPL profile classified in detail (aPL-S) or simplified aPL profile with classical thrombotic risk factors (GAPSS) was put into a scoring system. Both the aPL-S and GAPSS have shown a degree of accuracy in identifying high-risk APS patients, especially those at a high risk of thrombosis. However, there are several areas requiring improvement, or at least that clinicians should be aware of, before these instruments are applied in clinical practice. One such issue is standardisation of the aPL tests, including general testing of phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT). Additionally, clinicians may need to be aware of the patient's medical history, particularly with respect to the incidence of SLE, which influences the cutoff value for identifying high-risk patients.
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Affiliation(s)
- Kenji Oku
- Department of Medicine II, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo, 060-8638, Japan.
| | - Olga Amengual
- Department of Medicine II, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo, 060-8638, Japan
| | - Shinsuke Yasuda
- Department of Medicine II, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo, 060-8638, Japan
| | - Tatsuya Atsumi
- Department of Medicine II, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo, 060-8638, Japan
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Chaturvedi S, McCrae KR. Clinical Risk Assessment in the Antiphospholipid Syndrome: Current Landscape and Emerging Biomarkers. Curr Rheumatol Rep 2018; 19:43. [PMID: 28711993 DOI: 10.1007/s11926-017-0668-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW Laboratory criteria for the classification of antiphospholipid syndrome include the detection of a lupus anticoagulant and/or anticardiolipin and anti-β2-glycoprotein I antibodies. However, the majority of patients who test positive in these assays do not have thrombosis. Current risk-stratification tools are largely limited to the antiphospholipid antibody profile and traditional thrombotic risk factors. RECENT FINDINGS Novel biomarkers that correlate with disease activity and potentially provide insight into future clinical events include domain 1 specific anti-β2GPI antibodies, antibodies to other phospholipids or phospholipid/protein antigens (such as anti-PS/PT), and functional/biological assays such as thrombin generation, complement activation, levels of circulating microparticles, and annexin A5 resistance. Clinical risk scores may also have value in predicting clinical events. Biomarkers that predict thrombosis risk in patients with antiphospholipid antibodies have been long sought, and several biomarkers have been proposed. Ultimately, integration of biomarkers with established assays and clinical characteristics may offer the best chance of identifying patients at highest risk of APS-related complications.
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Affiliation(s)
- Shruti Chaturvedi
- Division of Hematology and Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37235, USA
| | - Keith R McCrae
- Department of Cellular and Molecular Medicine, Taussig Cancer Institute, Cleveland Clinic, CA6-154, 9500 Euclid Avenue, Cleveland, OH, 44195, USA.
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Kopytek M, Natorska J, Undas A. Antiphosphatidylserine/prothrombin (aPS/PT) antibodies are associated with Raynaud phenomenon and migraine in primary thrombotic antiphospholipid syndrome. Lupus 2018; 27:812-819. [DOI: 10.1177/0961203317751644] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Objectives Antibodies to phosphatidylserine/prothrombin complex (aPS/PT) detectable in sera of some patients with antiphospholipid syndrome (APS) have been shown to correlate with thrombosis. However, associations of aPS/PT antibodies with APS related disorders remain unclear. Aim To evaluate whether there are any associations between aPS/PT antibodies and Raynaud phenomenon, migraine and/or valvular lesions in primary thrombotic APS (PAPS). Methods We enrolled 67 consecutive patients (56 women) with thrombotic PAPS (VTE in 80.6%), aged 46.2 ± 13.5 years. The exclusion criteria were: acute coronary syndromes or stroke within preceding 6 months, cancer, severe comorbidities and pregnancy. The IgG and IgM aPS/PT antibodies were determined by ELISA with the cut-off of 30 units. We recorded Raynaud phenomenon, migraine and valvular lesions. Results Positive IgM or/and IgG aPS/PT antibodies were observed in 29 patients (43.3%), with a higher prevalence of IgM antibodies ( n = 27, 40.3%) compared with IgG isotype ( n = 12, 17.9%, p = 0.014). aPS/PT antibodies were observed most commonly in patients with triple aPL ( n = 12, 85.7%) compared with those with double ( n = 5, 35.7%) or single aPL antibodies (n = 12, 30.8%, p = 0.03), with no association with demographics, the ANA titre, the type of thrombotic events or medications. Raynaud phenomenon, migraine and valvular lesions were observed in 15% ( n = 10), 30% ( n = 20) and 18% ( n = 12) of the patients, respectively. Raynaud phenomenon and migraine, but not valvular lesions, were markedly more frequent in PAPS patients presenting with positive aPS/PT antibodies ( n = 10, 34.5% vs. n = 0, 0%; p = 0.0001). Conclusions In PAPS patients aPS/PT antibodies are related to the occurrence of both Raynaud phenomenon and migraine.
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Affiliation(s)
- M Kopytek
- John Paul II Hospital, Kraków, Poland
| | - J Natorska
- John Paul II Hospital, Kraków, Poland
- Institute of Cardiology, Jagiellonian University Medical College, Kraków, Poland
| | - A Undas
- John Paul II Hospital, Kraków, Poland
- Institute of Cardiology, Jagiellonian University Medical College, Kraków, Poland
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Amiral J, Peyrafitte M, Dunois C, Vissac AM, Seghatchian J. Anti-phospholipid syndrome: Current opinion on mechanisms involved, laboratory characterization and diagnostic aspects. Transfus Apher Sci 2017; 56:612-625. [PMID: 28803708 DOI: 10.1016/j.transci.2017.07.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Anti-phospholipid syndrome is a complex and severe clinical situation, associated with symptoms such as recurrent thrombosis, arterial or venous, at any site, pregnancy loss, and other related syndromes. These clinical burdens, are highly variable from patient to patient, and are associated with biological abnormalities, such as the presence of the Lupus Anticoagulant or phospholipid dependent antibodies, confirmed on two occasions at least 12 weeks apart. From the diagnosis standpoint, both, functional (clotting) or immunological assays, are difficult to standardize and to optimize, due to the absence of reference material, or a characteristic clinical group, and international reference preparations. Large cohort studies are necessary for defining the usefulness of each assay, in terms of specificity, sensitivity, accuracy and for following-up the disease evolution. Clotting assays are based on Activated Partial Thromboplastin Time (APTT) and diluted Russell Viper Venom Time (dRVVT), performed at low and high phospholipid concentration, or on 1:1 mixtures of tested sample and a normal plasma pool. They allow evaluation of the paradoxal effects of LAs, which are pro-thrombotic in vivo, and anticoagulant in vivo. Use of synthetic phospholipids improves assay specificities and sensitivities, especially in patients treated with anticoagulants. Immunoassays can also be used for testing phospholipid dependent antibodies, first identified and measured as anti-cardiolipin antibodies, but now characterized as targeted to phospholipid cofactor proteins: mainly β2GP1 (which exposes cryptic epitopes upon binding to phospholipids), and in some cases prothrombin, and more rarely Protein S, Factor XIII, Protein Z or Annexin V. Use of optimized assays designed with well-characterized anionic phospholipids, then complexed with highly purified phospholipid cofactor protein (mainly β2GP1), offers a better link between reactivity and clinical associations, than the former assays which were empirically designed with cardiolipin. Standardization also remains complicated due to the absence of international standards and harmonized quantitation units. Validation on large cohorts of negative and positive patients remains the key approach for defining assay performance and clinical usefulness. Laboratory practice for all these methods is now greatly facilitated thanks to the use of automated instruments and dedicated software. Along with clinical criteria, laboratory assays are of great usefulness for identification and confirmation of the anti-phospholipid syndrome and they allow disease follow-up when appropriate patient management is in place.
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Affiliation(s)
- Jean Amiral
- SH-Consulting, Andrésy, France; Scientific and Technical Advisor for Hyphen BioMed, Sysmex Group, Neuville-sur-Oise, France.
| | | | - Claire Dunois
- Clinical Studies Director, HYPHEN BioMed, Neuville-sur-Oise, France
| | | | - Jerard Seghatchian
- International Consultancy in Blood Components Quality/Safety Improvement, Audit/Inspection and DDR Strategies, London, UK.
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Amengual O, Forastiero R, Sugiura-Ogasawara M, Otomo K, Oku K, Favas C, Delgado Alves J, Žigon P, Ambrožič A, Tomšič M, Ruiz-Arruza I, Ruiz-Irastorza G, Bertolaccini ML, Norman GL, Shums Z, Arai J, Murashima A, Tebo AE, Gerosa M, Meroni PL, Rodriguez-Pintó I, Cervera R, Swadzba J, Musial J, Atsumi T. Evaluation of phosphatidylserine-dependent antiprothrombin antibody testing for the diagnosis of antiphospholipid syndrome: results of an international multicentre study. Lupus 2016; 26:266-276. [PMID: 27510605 DOI: 10.1177/0961203316660203] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objective A task force of scientists at the International Congress on Antiphospholipid Antibodies recognized that phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT) might contribute to a better identification of antiphospholipid syndrome (APS). Accordingly, initial and replication retrospective, cross-sectional multicentre studies were conducted to ascertain the value of aPS/PT for APS diagnosis. Methods In the initial study (eight centres, seven countries), clinical/laboratory data were retrospectively collected. Serum/plasma samples were tested for IgG aPS/PT at Inova Diagnostics (Inova) using two ELISA kits. A replication study (five centres, five countries) was carried out afterwards. Results In the initial study ( n = 247), a moderate agreement between the IgG aPS/PT Inova and MBL ELISA kits was observed ( k = 0.598). IgG aPS/PT were more prevalent in APS patients (51%) than in those without (9%), OR 10.8, 95% CI (4.0-29.3), p < 0.0001. Sensitivity, specificity, positive (LR+) and negative (LR-) likelihood ratio of IgG aPS/PT for APS diagnosis were 51%, 91%, 5.9 and 0.5, respectively. In the replication study ( n = 214), a moderate/substantial agreement between the IgG aPS/PT results obtained with both ELISA kits was observed ( k = 0.630). IgG aPS/PT were more prevalent in APS patients (47%) than in those without (12%), OR 6.4, 95% CI (2.6-16), p < 0.0001. Sensitivity, specificity, LR + and LR- for APS diagnosis were 47%, 88%, 3.9 and 0.6, respectively. Conclusions IgG aPS/PT detection is an easily performed laboratory parameter that might contribute to a better and more complete identification of patients with APS.
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Affiliation(s)
- O Amengual
- 1 Division of Rheumatology, Endocrinology and Nephrology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - R Forastiero
- 2 Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMeTTyB), Universidad Favaloro-CONICET, Departamento de Fisiologia, Hemostasia y Trombosis, Buenos Aires, Argentina
| | - M Sugiura-Ogasawara
- 3 Department of Obstetrics and Gynecology, Nagoya City University, Graduated School of Medical Sciences, Nagoya, Japan
| | - K Otomo
- 1 Division of Rheumatology, Endocrinology and Nephrology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - K Oku
- 1 Division of Rheumatology, Endocrinology and Nephrology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - C Favas
- 4 Department of Medicine IV, Fernando Fonseca Hospital, Amadora and CEDOC/NOVA Medical School, Lisbon, Portugal
| | - J Delgado Alves
- 4 Department of Medicine IV, Fernando Fonseca Hospital, Amadora and CEDOC/NOVA Medical School, Lisbon, Portugal
| | - P Žigon
- 5 Department of Rheumatology, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - A Ambrožič
- 5 Department of Rheumatology, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - M Tomšič
- 5 Department of Rheumatology, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - I Ruiz-Arruza
- 6 Autoimmune Diseases Research Unit, Department of Internal Medicine, Biocruces Health Research Institute, Hospital Universitario Cruces, University of The Basque Country, Spain
| | - G Ruiz-Irastorza
- 6 Autoimmune Diseases Research Unit, Department of Internal Medicine, Biocruces Health Research Institute, Hospital Universitario Cruces, University of The Basque Country, Spain
| | - M L Bertolaccini
- 7 Academic Department of Vascular Surgery, Cardiovascular Division, King's College London, UK
| | - G L Norman
- 8 Inova Diagnostics Inc., San Diego, CA, USA
| | - Z Shums
- 8 Inova Diagnostics Inc., San Diego, CA, USA
| | - J Arai
- 9 Medical and Biological Laboratories, Co. Ltd, Nagano, Japan
| | - A Murashima
- 10 Center of Maternal-Fetal, Neonatal and Reproductive Medicine, National Center for Child Health and Development, Tokyo, Japan
| | - A E Tebo
- 11 Department of Pathology, University of Utah and ARUP Laboratories, Salt Lake City, UT, USA
| | - M Gerosa
- 12 Department of Clinical Sciences and Community Health, Istituto Auxologico Italiano, University of Milan, Milan, Italy
| | - P L Meroni
- 12 Department of Clinical Sciences and Community Health, Istituto Auxologico Italiano, University of Milan, Milan, Italy
| | - I Rodriguez-Pintó
- 13 Department of Autoimmune Diseases, Hospital Clínic, University of Barcelona, Barcelona, Catalonia, Spain
| | - R Cervera
- 13 Department of Autoimmune Diseases, Hospital Clínic, University of Barcelona, Barcelona, Catalonia, Spain
| | - J Swadzba
- 14 Department of Medicine Jagiellonian University, Cracow, Poland
| | - J Musial
- 14 Department of Medicine Jagiellonian University, Cracow, Poland
| | - T Atsumi
- 1 Division of Rheumatology, Endocrinology and Nephrology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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Diagnóstico en el síndrome antifosfolipídico: desde una perspectiva histórica a la aparición de nuevos autoanticuerpos. Med Clin (Barc) 2016; 146:555-60. [DOI: 10.1016/j.medcli.2016.01.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/11/2016] [Accepted: 01/13/2016] [Indexed: 01/17/2023]
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Peterson LK, Willis R, Harris EN, Branch WD, Tebo AE. Antibodies to Phosphatidylserine/Prothrombin Complex in Antiphospholipid Syndrome: Analytical and Clinical Perspectives. Adv Clin Chem 2016; 73:1-28. [PMID: 26975968 DOI: 10.1016/bs.acc.2015.10.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombosis and/or pregnancy-related morbidity accompanied by persistently positive antiphospholipid antibodies (aPL). Current laboratory criteria for APS classification recommend testing for lupus anticoagulant as well as IgG and IgM anticardiolipin, and beta-2 glycoprotein I (anti-β2GPI) antibodies. However, there appears to be a subset of patients with classical APS manifestations who test negative for the recommended criteria aPL tests. While acknowledging that such patients may have clinical features that are not of an autoimmune etiology, experts also speculate that these "seronegative" patients may test negative for relevant autoantibodies as a result of a lack of harmonization and/or standardization. Alternatively, they may have aPL that target other antigens involved in the pathogenesis of APS. In the latter, autoantibodies that recognize a phosphatidylserine/prothrombin (PS/PT) complex have been reported to be associated with APS and may have diagnostic relevance. This review highlights analytical and clinical attributes associated with PS/PT antibodies, taking into consideration the performance characteristics of criteria aPL tests in APS with specific recommendations for harmonization and standardization efforts.
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Affiliation(s)
- Lisa K Peterson
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - Rohan Willis
- Rheumatology/Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | | | - Ware D Branch
- Maternal Fetal Medicine, University of Utah and Intermountain Healthcare, Salt Lake City, Utah, USA
| | - Anne E Tebo
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA; ARUP Laboratories, Institute of Clinical and Experimental Pathology, Salt Lake City, Utah, USA.
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