RESUMEN
Unprovoked (or provoked by mild risk factors) venous thromboembolism (VTE) in young patients, VTE in uncommon sites, or cases of unexplained VTE recurrence may be positive for antiphospholipid antibodies (aPL) and thus may be diagnosed with antiphospholipid syndrome (APS). The evaluation of aPL is standardized using immunological tests for anticardiolipin and anti-ß2-glycoprotein I. The determination of functional antibodies (lupus anticoagulant) is less standardized, especially in patients on anticoagulant treatment. Patients positive for all the three tests are at high risk of recurrence, which, in turn, might lead to chronic obstruction of pulmonary vessels (chronic thromboembolic pulmonary hypertension). Randomized clinical trials have shown that triple-positive patients should be treated with vitamin K antagonists maintaining an international normalized ratio between 2 and 3. Whether patients with VTE and incomplete aPL profile can be treated with direct oral anticoagulants should be further investigated.
Asunto(s)
Síndrome Antifosfolípido , Tromboembolia Venosa , Humanos , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/tratamiento farmacológico , Síndrome Antifosfolípido/diagnóstico , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/etiología , Anticuerpos Antifosfolípidos , Anticoagulantes/efectos adversos , Inhibidor de Coagulación del Lupus/uso terapéuticoRESUMEN
BACKGROUND: Patients presenting for surgery may have isolated or combined prolonged activated partial thromboplastin time (aPTT) and/or prothrombin time (PT). In patients not receiving anticoagulants or with no identifiable cause for abnormal clot formation, a mixing study is performed. The index of circulating anticoagulant (ICA) has been used to predict the presence of an inhibitor, usually a lupus anticoagulant. METHODS: We retrospectively reviewed the results of mixing studies performed at Northwestern Memorial Hospital, between January 1, 2010 and February 29, 2012. We determined the number of samples that normalized or remained prolonged, the clotting factors associated with prolonged test results, and the presence of coagulation inhibitors. We calculated the ICA in the samples with prolonged aPTT and PT to determine its ability to predict a lupus anticoagulant. The primary comparison of interest was the diagnostic utility of the ICA at cutoff values of 11% for predicting the presence of lupus anticoagulant. RESULTS: There were 269 mixing studies performed: 131 samples with prolonged aPTT; 95 with prolonged PT; and 43 with both prolonged aPTT and prolonged PT. Of the samples with a prolonged aPTT, 55 of 131 (42%) normalized, 36 of 131 (27%) partially corrected, and 40 of 131 (31%) remained prolonged. Thirty-three of 95 samples (35%) with prolonged PT normalized, while 62 of 95 (65%) remained prolonged. Eight of 43 (19%) mixing studies of patients with prolonged PT and aPTT normalized; the aPTT normalized, but the PT remained prolonged in 17 of 43 (39%); the PT normalized, but the aPTT remained prolonged in 7 of 43 (16%); and both tests remained prolonged in 11 of 43 (26%) samples. Prolongations in the aPTT were primarily associated with low activities of CF XII, while the majority of the prolongations in PT were secondary to low activities in CF VII. Combined prolongations were secondary to deficiencies in both the intrinsic and extrinsic as well as the common pathways. An ICA >11% had 100% (95% CI, 59%-100%) sensitivity, 53% (95% CI, 35%-70%) specificity, and 77% (95% CI, 62%-92%) accuracy in predicting the presence of lupus anticoagulant in patients with prolonged aPTT. CONCLUSIONS: Normalization of the aPTT and PT in a mixing study was associated with low clotting factor activity. The ICA may be helpful in predicting the presence of a lupus anticoagulant. As anesthesiologists take ownership of the perioperative surgical home, we need to understand the clinical implications of the results of mixing studies.
Asunto(s)
Pruebas de Coagulación Sanguínea/métodos , Coagulación Sanguínea/efectos de los fármacos , Tiempo de Tromboplastina Parcial , Tiempo de Protrombina , Adulto , Anciano , Anticoagulantes/administración & dosificación , Anticoagulantes/farmacología , Trastornos de la Coagulación Sanguínea , Factores de Coagulación Sanguínea/farmacología , Femenino , Humanos , Inhibidor de Coagulación del Lupus/uso terapéutico , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Riesgo , Trombosis/prevención & controlRESUMEN
This present case pertains to a 48-year-old woman with a history of antiphospholipid syndrome, who presented with progressive fatigue, generalized weakness, and orthopnea acutely. She had a prior diagnosis of antiphospholipid syndrome with recurrent deep vein thromboses (DVTs) and repeated demonstration of lupus anticoagulants. She presented in cardiogenic shock with markedly elevated troponin and global myocardial dysfunction on echocardiography, and cardiac catheterization revealed minimal disease. Cardiac magnetic resonance imaging was performed, which revealed findings of perfusion defects and microvascular obstruction, consistent with the pathophysiology of catastrophic antiphospholipid syndrome (CAPS). Diagnosis was made based on supportive imaging, including head magnetic resonance imaging (MRI) revealing multifocal, acute strokes; microvascular thrombosis in the dermis; and subacute renal infarctions. The patient was anticoagulated with intravenous unfractionated heparin and received high-dose methylprednisolone, plasmapheresis, intravenous immunoglobulin, and one dose each of rituximab and cyclophosphamide. She convalesced with eventual myocardial recovery after a complicated course. The diagnosis of CAPS relies on the presence of (1) antiphospholipid antibodies and (2) involvement of multiple organs in a microangiopathic thrombotic process with a close temporal association. The myocardium is frequently affected, and heart failure, either as the presenting symptom or cause of death, is common. Despite echocardiographic evidence of myocardial dysfunction in such patients, MRIs of CAPS have not previously been reported. This case highlights the utility in assessing the involvement of the myocardium by the microangiopathic process with MRI. Because the diagnosis of CAPS requires involvement in multiple organ systems, cardiac MRI is likely an underused tool that not only reaffirms the pathophysiology of CAPS, but could also clue clinicians in to the possibility of a diffuse thrombotic process.
Asunto(s)
Anticuerpos Antifosfolípidos/sangre , Síndrome Antifosfolípido/complicaciones , Enfermedades Renales/etiología , Choque Cardiogénico/etiología , Trombosis de la Vena/etiología , Síndrome Antifosfolípido/diagnóstico , Enfermedad Catastrófica , Femenino , Heparina/uso terapéutico , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Inhibidor de Coagulación del Lupus/uso terapéutico , Imagen por Resonancia Magnética , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , PlasmaféresisRESUMEN
The incidence of thrombosis in the purely obstetric form of antiphospholipid syndrome is uncertain. We performed a 10-year observational study of 1592 nonthrombotic women who had experienced 3 consecutive spontaneous abortions before the 10th week of gestation or 1 fetal death at or beyond the 10th week of gestation. We compared the frequencies of thrombotic events among women positive for antiphospholipid Abs (n = 517), women carrying the F5 6025 or F2 rs1799963 polymorphism (n = 279), and women with negative thrombophilia screening results (n = 796). The annual rates of deep vein thrombosis (1.46%; range, 1.15%-1.82%), pulmonary embolism (0.43%; range, 0.26%-0.66%), superficial vein thrombosis (0.44%; range, 0.28%-0.68%), and cerebrovascular events (0.32%; range, 0.18%-0.53%) were significantly higher in aPLAbs women than in the other groups despite low-dose aspirin primary prophylaxis. Women carrying 1 of the 2 polymorphisms did not experience more thrombotic events than women who screened negative for thrombophilia. Lupus anticoagulant was a risk factor for unprovoked proximal and distal deep and superficial vein thrombosis and women in the upper quartile of lupus anticoagulant activity had the highest risk. Despite data suggesting that aPLAbs may induce pregnancy loss through nonthrombotic mechanisms, women with purely obstetric antiphospholipid syndrome are at risk for thrombotic complications.
Asunto(s)
Aborto Espontáneo/epidemiología , Síndrome Antifosfolípido/epidemiología , Factor V/genética , Polimorfismo Genético/genética , Complicaciones del Embarazo/epidemiología , Protrombina/genética , Trombosis/epidemiología , Aborto Espontáneo/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antifosfolípidos/sangre , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/genética , Femenino , Estudios de Seguimiento , Francia/epidemiología , Humanos , Incidencia , Inhibidor de Coagulación del Lupus/uso terapéutico , Masculino , Persona de Mediana Edad , Embarazo , Complicaciones del Embarazo/etiología , Estudios Prospectivos , Factores de Riesgo , Trombofilia/epidemiología , Trombofilia/etiología , Trombosis/etiología , Trombosis de la Vena/epidemiología , Trombosis de la Vena/etiología , Adulto JovenRESUMEN
We report the cases of two children who presented with autoimmune hemolytic anemia (AIHA) as an initial presentation of systemic lupus erythematosus (SLE). Both patients had a positive Coombs test, anemia, and an increased number of spherocytes in their blood smear. The patient in Case 1 presented with fever, urticarial erythema, facial paresis, AIHA, and leucopenia. Immunological screening revealed low complement protein levels and positive anti-nuclear antibody, anti-double-stranded DNA, and antiphospholipid antibody results. A further laboratory workup revealed a positive lupus anticoagulant (LA) result and low factor II levels. She was diagnosed with lupus anticoagulant hypoprothrombinemia syndrome (LAHPS) in addition to SLE. The patient in Case 2 presented with fever, butterfly rash, thyroid enlargement, leucopenia, and AIHA. She was diagnosed with SLE with thyroiditis. Both patients were started on combined immunosuppressive therapy, and both patients' clinical symptoms finally resolved. A literature review on childhood SLE showed that AIHA is common in patients with SLE. LAHPS is an uncommonly identified cause of bleeding in patients with SLE, and it must be considered when evaluating children with a positive LA result.
Asunto(s)
Anemia Hemolítica Autoinmune , Síndrome Antifosfolípido , Leucopenia , Lupus Eritematoso Sistémico , Trombocitopenia , Anemia Hemolítica Autoinmune/complicaciones , Anemia Hemolítica Autoinmune/diagnóstico , Niño , Femenino , Humanos , Leucopenia/etiología , Inhibidor de Coagulación del Lupus/uso terapéutico , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/diagnósticoRESUMEN
INTRODUCTION: Breast cancer (BC) is the most diagnosed cancer worldwide. Multiple myeloma (MM) is a hematologic malignancy characterized by the overproduction of monoclonal antibodies in the bone marrow. Systemic lupus erythematosus (SLE) is distinguished by the aberrant activity of the immune system with heterogeneous clinical manifestations. The coexistence of more than one major illness in a patient can present a diagnostic challenge for clinical physicians, especially when the comorbid diseases share a similar clinical presentation. Herein, we report an unusual case of secondary synchronous diagnosis of MM and SLE after BC treatment. PATIENT CONCERNS: A 69-year-old female patient with breast cancer experienced severe skin itching and rashes on the face, anterior chest wall, back, and trunk for two days before admission. She had high levels of immunoglobulin and anti-nuclear antibodies; low levels of complements 3 and 4; positive anti-cardiolipin-IgM, anti-beta 2 glycoprotein-1 (anti-ß2GP1) antibodies, and lupus anticoagulant results at serological testing. DIAGNOSIS: The postoperative pathology report showed ductal carcinoma in situ in the right breast. SLE was confirmed based on the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) criteria. IgG-κ type multiple myeloma was confirmed by bone marrow biopsy, and the patient was synchronously diagnosed with SLE and MM after BC treatment. INTERVENTIONS: Glucocorticoids and immunosuppressive agents, including intravenous hydrocortisone (5 g every 8 hours) and oral hydroxychloroquine (Plaquenil) (200 mg twice daily) were administered to treat SLE. One capsule of thalidomide 50 mg was administered orally every night at bedtime for MM. OUTCOMES: The patient died two days later, shortly after the administration of drugs, due to multiple organ failures secondary to pneumonia and respiratory failure. CONCLUSION: This is a case of MM and SLE after BC treatment. The present challenge was the early detection and accurate diagnosis of the secondary major illnesses, as the clinical manifestations were similar and non-specific between these two diseases. Awareness and prompt recognition of the common clinical symptoms of SLE and MM should be considered by clinical physicians to avoid delayed diagnoses and facilitate early treatment for a better prognosis.
Asunto(s)
Neoplasias de la Mama , Lupus Eritematoso Sistémico , Mieloma Múltiple , Anciano , Anticuerpos Monoclonales/uso terapéutico , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Femenino , Glicoproteínas/uso terapéutico , Humanos , Hidrocortisona/uso terapéutico , Hidroxicloroquina/uso terapéutico , Inmunoglobulina G/uso terapéutico , Inmunoglobulina M/uso terapéutico , Inmunosupresores/uso terapéutico , Inhibidor de Coagulación del Lupus/uso terapéutico , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Mieloma Múltiple/complicaciones , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Talidomida/uso terapéuticoRESUMEN
Lupus anticoagulants (LAC) are antibodies which are detected by a prolongation of phospholipid-dependent coagulation assays, and are associated with thrombotic events and pregnancy complications in patients with the antiphospholipid syndrome. The antiphospholipid syndrome is defined by arterial or venous thrombosis and/or pregnancy morbidity and by laboratory diagnosis of antiphospholipid antibodies. The laboratory diagnosis is based on LAC and/or anticardiolipin and/or anti-beta2-glycoprotein I antibodies present in plasma, on two or more occasions at least 12 weeks apart. ALthough the presence of LAC correlates best with thrombosis, the Laboratory testing of LAC is not well standardized. In this article, the Laboratory evaluation of LAC will be explained, including the different tests that are recommended by the Israeli Sub-committee of Thrombosis and Hemostasis Laboratories, the possibility to evaluate LAC in patients treated with antithrombotic therapy, and how to report and interpret the results.
Asunto(s)
Anticuerpos Antifosfolípidos/sangre , Inhibidor de Coagulación del Lupus/uso terapéutico , Síndrome Antifosfolípido/tratamiento farmacológico , Coagulación Sanguínea/efectos de los fármacos , Técnicas de Laboratorio Clínico , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Factores Inmunológicos/efectos adversos , Factores Inmunológicos/uso terapéutico , Israel , Inhibidor de Coagulación del Lupus/efectos adversos , Inhibidor de Coagulación del Lupus/análisis , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/inmunología , Trombosis de la Vena/tratamiento farmacológicoRESUMEN
Functional tests for lupus anticoagulants (LA) as part of a thrombophilia workup are commonly performed in patients under anticoagulant therapy that may interfere with assay results. There is no consensus on how these tests should be assessed in patients on direct oral anticoagulants (DOACs). In this retrospective cohort study, we analysed data from patients with a history of thrombosis in whom dilute Russell viper venom time (dRVVT), LA-sensitive aPTT, and solid phase assays for antiphospholipid antibodies (aPL) were performed (n = 3,147, thereof 588 on rivaroxaban, 144 on apixaban, 1,179 on other anticoagulant drugs). The dRVVT ratio was correlated with rivaroxaban (r = 0.30, P < 10-4) but not with apixaban plasma levels. The LA-sensitive aPTT/aPTT ratio showed no correlation with DOAC levels. Correspondingly, the rate of patients with abnormal dRVVT test was significantly higher (P < 10-4) under rivaroxaban (88%) than in thrombosis patients without anticoagulant medication (6%), independent from their aPL plasma levels. No isolated positive results of functional LA testing in patients on anticoagulants could be confirmed in repeated testing after discontinuation of the medication (n = 40). These data indicate that rivaroxaban should be discontinued before functional LA testing is performed. However, viable interpretation of these tests appears to be less affected in patients on apixaban.
Asunto(s)
Anticoagulantes/uso terapéutico , Inhibidor de Coagulación del Lupus/uso terapéutico , Trombosis/tratamiento farmacológico , Administración Oral , Adulto , Anticuerpos Antifosfolípidos/uso terapéutico , Síndrome Antifosfolípido/tratamiento farmacológico , Coagulación Sanguínea/efectos de los fármacos , Pruebas de Coagulación Sanguínea/métodos , Dabigatrán/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial/métodos , Tiempo de Protrombina/métodos , Pirazoles/uso terapéutico , Piridonas/uso terapéutico , Estudios Retrospectivos , Rivaroxabán/uso terapéutico , Trombofilia/tratamiento farmacológicoAsunto(s)
Anticuerpos Antifosfolípidos/sangre , Síndrome Antifosfolípido/diagnóstico , Síndrome Antifosfolípido/tratamiento farmacológico , Inhibidor de Coagulación del Lupus/uso terapéutico , Animales , Anticuerpos Antifosfolípidos/efectos adversos , Síndrome Antifosfolípido/inmunología , Humanos , Inhibidor de Coagulación del Lupus/inmunología , Trombosis/diagnóstico , Trombosis/etiología , Trombosis/inmunología , Resultado del Tratamiento , Warfarina/uso terapéuticoRESUMEN
OBJECTIVE: Determination of lupus anticoagulants (LA) is an important, but still challenging test in the diagnosis of antiphospholipid syndrome (APS). This is especially the case in patients using one of the direct oral anticoagulants (DOACs). The aim of our study was to examine the influence of these drugs on DRVVT assays from two companies (in each case: screening test, confirming test and calculated ratio) and on aPTT and lupus-sensitive aPTT. METHODS: We used plasma samples from healthy volunteers spiked with the DOACs dabigatran, rivaroxaban and apixaban (0, 10, 30, 50, 100â¯ng/mL) for testing. Furthermore, samples from patients receiving a DOAC were investigated. The plasma concentrations of the DOACs were determined using ultra-performance liquid chromatography/electrospray ionization-tandem mass spectrometry (UPLC-MS/MS). RESULTS: Depending on type and concentration, all the DOACs resulted in pathological values in the DRVVT screening assays. In samples spiked with apixaban, no influence on the DRVVT normalized ratio of the two assays was observed, but 7 to 15% of samples from patients receiving apixaban displayed pathological values. In contrast, up to 71% of dabigatran-spiked samples showed normalized ratio values above the cut-off, whereas there was no influence in the patients' samples. In both spiked and patient samples containing rivaroxaban, the DRVVT assays were influenced. CONCLUSION: LA diagnostics should, under DOAC therapy, be limited to situations in which time-critical evaluation is warranted. It is crucial to take into account the finding that even samples containing DOAC concentrations below the limit of detection of the drugs may lead to false-positive DRVVT measurements.
Asunto(s)
Anticoagulantes/uso terapéutico , Pruebas de Coagulación Sanguínea/métodos , Inhibidor de Coagulación del Lupus/uso terapéutico , Administración Oral , Anticoagulantes/farmacología , Femenino , Humanos , Inhibidor de Coagulación del Lupus/farmacología , MasculinoRESUMEN
Lupus anticoagulant (LAC) is an in vitro phenomenon determining a phospholipid-dependent elongation of clotting times. The presence of LAC associated with anticardiolipin (aCL) and anti-ß2 glycoprotein I (anti-ß2GPI) antibodies is strongly associated with thrombosis and pregnancy morbidity. Direct oral anticoagulants (DOACs) targeting thrombin and factor Xa are currently widely use to prevent and treat venous and arterial thromboembolism. Some concern has, however, been expressed about the possibility of false laboratory results during LAC assessment in patients taking these drugs. Several in vitro studies, spiking DOACs into normal plasma as well as ex vivo at peak levels in treated patients, led in false-positive LAC. The dilute Russell Viper Venom time is the assay that is most influenced by rivaroxaban, edoxaban, dabigatran and less by apixaban. Both screening and confirmatory tests have resulted equally prolonged for activated partial thromboplastin time and have not led to false-positive results, but this may depend on the type of reagent used for the test. Taipan/Ecarin snake venoms ratios, has been recommend by some investigators as they do not seem to be affected by rivaroxaban or edoxaban, but these tests are neither standardized nor generally available in clinical practice. In conclusion, for the time being it does not seem advisable to carry out LAC testing during anti-factor Xa and anti-factor IIa treatment because of the risk of false-positive results. Whenever needed in deciding the suspension of DOACs or in case of recurrent thrombosis, LAC determination should be carried out at trough better if DOAC concentration is known.
Asunto(s)
Anticoagulantes/uso terapéutico , Síndrome Antifosfolípido/tratamiento farmacológico , Síndrome Antifosfolípido/inmunología , Dabigatrán/uso terapéutico , Inhibidor de Coagulación del Lupus/uso terapéutico , Rivaroxabán/uso terapéutico , Administración Oral , Dabigatrán/administración & dosificación , Humanos , Inhibidor de Coagulación del Lupus/administración & dosificación , Rivaroxabán/administración & dosificaciónRESUMEN
Strategies to target nanoparticles to tumors that rely on surface modification with ligands that bind molecules overexpressed on cancer cells or the tumor neovasculature suffer from a major limitation: with delivery of toxic agents the amount of molecules available for targeting decreases with time; consequently, the efficiency of nanoparticle delivery is reduced. To overcome this limitation, here we propose an autocatalytic tumor-targeting mechanism based on targeting extracellular DNA (exDNA). exDNA is enriched in the tumor microenviroment and increases with treatment with cytotoxic agents, such as doxorubicin (DOX), due to release of DNA by dying tumor cells. We tested this approach using poly(lactic-co-glycolic acid) (PLGA) nanoparticles surface-conjugated with fragments of 3E10 (3E10EN), a lupus anti-DNA autoantibody. We demonstrated that 3E10EN-conjugated nanoparticles bound to DNA and preferentially localized to tumors in vivo. The efficiency of tumor localization of 3E10EN-conjugated, DOX-loaded nanoparticles increased with time and subsequent treatments, demonstrating an autocatalytic effect. 3E10EN-conjugated DOX-loaded nanoparticles exhibited a significant anti-tumor effect that was superior to all controls. This work demonstrates the promise of autocatalytic drug delivery mechanisms and establishes proof of concept for a new anti-DNA autoantibody-based approach for enhancing delivery of nanoparticles to tumors.
Asunto(s)
Anticuerpos Antinucleares/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/uso terapéutico , Inhibidor de Coagulación del Lupus/uso terapéutico , Neoplasias Mamarias Animales/tratamiento farmacológico , Animales , Anticuerpos Antinucleares/química , Anticuerpos Catalíticos , Línea Celular Tumoral , ADN/análisis , Doxorrubicina/química , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Ácido Láctico/química , Inhibidor de Coagulación del Lupus/química , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Microambiente TumoralRESUMEN
The recommended therapeutic range of International Normalized Ratio (INR) for oral anticoagulant treatment in patients with the antiphospholipid syndrome remains controversial. As a part of this controversy, it has been suggested that lupus anticoagulants (LA) could interfere with the determination of prothrombin time, thus questioning the validity of monitoring the treatment of these patients using INR. To clarify this point, we compared the values of INR obtained in the plasmas of two groups of patients, one without LA (n = 47), and the other with LA (n = 43). INR were determined using 8 different thromboplastin reagents on the same automated coagulation instrument. Chromogenic factor X, which is supposed to be insensitive to the presence of LA, was also measured. The results are the following: provided INR was calculated using calibrated reference plasmas, there was no significant difference between INR values obtained with the 8 reagents, both in the non-LA and in the LA groups (CV: 5.9 and 6.7%. respectively). Closer examination revealed that INR results obtained with one reagent (the recombinant thromboplastin Innovin) diverged from those of the 7 others, leading to an overestimation of INR, to a very large extent in some instances. However this effect was restricted to a subset of the patient population with LA (6 out of 43). Finally, the relationship between INR (average value obtained using the 8 reagents) and factor X was identical in non-LA and in LA patient groups. We conclude that, provided the reagents which display the LA interference are identified and excluded for this purpose, the INR system is valid for monitoring oral anticoagulant treatment in patients with LA.
Asunto(s)
Síndrome Antifosfolípido/tratamiento farmacológico , Inhibidor de Coagulación del Lupus/uso terapéutico , Administración Oral , Animales , Bovinos , Humanos , Relación Normalizada InternacionalRESUMEN
Fifteen years have passed since Hughes reported the detailed clinical description of antiphospholipid syndrome (APS), and it is now recognised as one of the most common prothrombotic disorders. Its main clinical features are recurrent thrombosis (both venous and arterial), recurrent pregnancy loss and thrombocytopenia associated with the presence of antiphospholipid antibodies (aPLs). aPLs are a heterogeneous group of autoantibodies detected by either clotting or immunological assays. They include lupus anticoagulant (LA), anticardiolipin antibodies (aCL) and antibodies against other phospholipids (PLs). Recently the aPLs family has expanded to include antibodies whose specificity are claimed to be directed not only towards PLs, but also towards plasma proteins and their complex with PLs. Animal models are providing important new data on clinical and pathogenic aspects of APS. The detection of antibodies against beta 2 glycoprotein I by a simple and rapid enzyme-linked immunosorbent assay (ELISA) may facilitate the recognition of "pathogenic" aCL in APS. Regarding the treatment of APS, long-term anticoagulation therapy is needed to prevent recurrences.
Asunto(s)
Síndrome Antifosfolípido/diagnóstico , Adulto , Distribución por Edad , Anciano , Animales , Anticuerpos Anticardiolipina/análisis , Síndrome Antifosfolípido/tratamiento farmacológico , Síndrome Antifosfolípido/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Incidencia , Londres/epidemiología , Inhibidor de Coagulación del Lupus/uso terapéutico , Masculino , Persona de Mediana Edad , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Complicaciones del Embarazo/epidemiología , Recurrencia , Distribución por SexoRESUMEN
A case of a successful pregnancy is presented in a woman with anti-phospholipid syndrome and habitual abortions. She was treated with heparin-salicyl therapy during her pregnancy. No complications were noted. The significance of the presence of anti-phospholipid antibodies is stressed. The other therapeutic possibilities are discussed.
Asunto(s)
Aborto Habitual/complicaciones , Síndrome Antifosfolípido/complicaciones , Aborto Habitual/tratamiento farmacológico , Aborto Habitual/inmunología , Adulto , Síndrome Antifosfolípido/tratamiento farmacológico , Síndrome Antifosfolípido/inmunología , Femenino , Heparina/uso terapéutico , Humanos , Inhibidor de Coagulación del Lupus/uso terapéutico , Embarazo , Resultado del Embarazo , Salicilatos/uso terapéuticoRESUMEN
Phlegmasia cerulea dolens (PCD) is an aggressive and life-threatening form of venous thrombosis complicated by ischemic necrosis. Massive thrombosis extends to collateral veins resulting in venous congestion with fluid sequestration in the interstitium causing collapse of arterioles, which progresses to ischemia and, if severe, circulatory collapse and shock. The mortality rate for PCD is as high as 40%, especially when gangrene develops. PCD has been associated with acquired thrombophilias, including malignancy and antiphospholipid syndrome (APS). We present a unique case of a patient with PCD refractory to anticoagulant and thrombolytic therapy, whose fulminant course was attributed to concurrent cholangiocarcinoma and antiphospholipid antibodies identified by a positive lupus anticoagulant assay. This case highlights the importance of uncovering precipitating causes of thromboembolism, which may offer prognostic information and may necessitate therapy beyond anticoagulation and thrombolysis to reduce the morbidity of PCD. The current literature on PCD and APS, along with their associations with malignancy, is reviewed.
Asunto(s)
Colangiocarcinoma/etiología , Gangrena/complicaciones , Inhibidor de Coagulación del Lupus/uso terapéutico , Tromboflebitis/complicaciones , Colangiocarcinoma/patología , Gangrena/diagnóstico , Gangrena/patología , Humanos , Inhibidor de Coagulación del Lupus/administración & dosificación , Masculino , Persona de Mediana Edad , Tromboflebitis/diagnóstico , Tromboflebitis/patologíaRESUMEN
BACKGROUND: Patients with antiphospholipid syndrome (APS) display a heterogeneous population of antibodies with beta(2) glycoprotein-1 (ß(2)GP1) as the major antigen. OBJECTIVES: We isolated and characterized human mAbs directed against ß(2)GP1 from the immune repertoire of APS patients. METHODS: Variable heavy chain repertoires from B cells from two APS patients with anti-ß(2)GP1 antibodies were cloned into the pHEN1-VLrep vector. Constructed full-length IgG antibodies were tested for lupus anticoagulant (LAC) activity and binding to ß(2)GP1 and its domains. RESULTS: Two clones of each patient were selected on the basis of the reactivity of single chain Fv (scFv) fragments displayed on phages towards full-length ß(2)GP1 and its isolated domain I. The affinity of selected antibodies for ß(2)GP1 was lost when transforming from phages to monovalent scFvs, and was regained when antibodies were constructed as complete IgG, indicating a role for bivalency in binding to ß(2)GP1. Both selected clones from patient 2 recognized domain I of ß(2)GP1, and for both clones selected from patient 1, binding required the presence of both domain I and domain II. All mAbs displayed LAC activity in both activated partial thromboplastin time-based and dilute Russell's viper venom test-based clotting assays and in thrombin generation. CONCLUSIONS: In this study, we show successful cloning of patient-derived mAbs that require domain I of ß(2)GP1 for binding, and that display LAC activity that is dependent on their affinity for ß(2)GP1. These antibodies can help us to gain more insights into the pathogenesis of APS, and may facilitate standardization of APS diagnosis.
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Anticuerpos Monoclonales/inmunología , Inhibidor de Coagulación del Lupus/uso terapéutico , beta 2 Glicoproteína I/inmunología , beta 2 Glicoproteína I/uso terapéutico , Secuencia de Aminoácidos , Anticuerpos Monoclonales/química , Ensayo de Inmunoadsorción Enzimática , Humanos , Datos de Secuencia Molecular , Homología de Secuencia de AminoácidoRESUMEN
BACKGROUND: Results for lupus anticoagulant (LA) are currently expressed as ratio of patient-to-normal clotting times (LA-ratio). Yet, numerical results do vary according to the method used for testing, thus making difficult the between-method comparison of results. We hypothesized that the standardization model currently used for the INR for patients on oral-anticoagulants (OAT) would be of value also for LA standardization. PATIENTS AND METHODS: To test this hypothesis we determined a sensitivity index valid for LA (called LASI) for six LA-detection methods against a common-standard using two sets of calibration-plasmas: (i)normal-plasmas spiked with IgG derived from patients strongly-positive for LA or (ii)plasmas from LA-positive patients. The LASI was then used to convert the LA-ratio into the standardized-LA-ratio (SLA-ratio) according to the equation: SLA-ratio = (LA-ratio)(LASI). RESULTS: We demonstrate that (i)the model is feasible because calibration plots of log-transformed clotting times obtained for the LA-detection methods-vs.-the common-standard gave acceptable LASI values; (ii)the model is effective because between-method variability expressed as coefficient of variation, which was 42.8% with results expressed as LA-ratio, decreased to 7.8% with results expressed as SLA-ratio; (iii)the LASI value calculated with the LA-positive plasmas is more effective in minimizing between-method variability than the LASI value calculated with IgG-spiked plasmas. CONCLUSIONS: A model of LA calibration similar to the INR for patients on OAT is feasible by using plasmas from LA-positive patients instead of patients on OAT. Potential application of the model are:(i)to compare the relative responsiveness of different LA-detection methods,(ii)to minimize differences between their results and (iii)to quantify LA potency.
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Pruebas de Coagulación Sanguínea/normas , Inhibidor de Coagulación del Lupus/uso terapéutico , Calibración , Estudios de Factibilidad , Humanos , Relación Normalizada Internacional/normas , Estándares de Referencia , Reproducibilidad de los ResultadosRESUMEN
Warfarin therapy is used in lupus anticoagulant patients with thrombosis and yet the prothrombin time (PT)/international normalized ratio (INR) in these patients can sometimes be falsely elevated. Both a PT-based factor II (FII) assay and a chromogenic, enzymatic factor X (CFX) assay have been used for monitoring when the INR may be artifactual. This study compared FII and CFX assays in lupus anticoagulant-positive and lupus anticoagulant-negative warfarin-treated patients in a cross-sectional study of samples from 21 lupus anticoagulant-positive and 19 lupus anticoagulant-negative outpatients. Plasma samples were simultaneously measured for FII and CFX and the ratio of FII/CFX was used to measure concordance. Compared with lupus anticoagulant-negative patients 14 of the 21 lupus anticoagulant-positive patients had lower FII/CFX ratios (P < 0.01). Three of the patients had ratios less than 0.6 indicating strong disagreement (P < 0.0001). The patient with the lowest FII/CFX ratio had evidence suggesting a specific antibody to FII. Another patient showed that the discordance between FII and CFX varied over time. The CFX assay in the laboratory was technically superior, more precise, and less costly. The CFX assay is preferred for warfarin therapy monitoring in lupus anticoagulant patients when INR artifacts are suspected.