Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0409974 (lupus)
 22,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The significance of ADAMTS13 deficiency in adult thrombotic microangiopathy (TMA) remains controversial. In an attempt to define the characteristics of adult TMA with severe ADAMTS13 deficiency, we determined 2 groups of patients on the basis of ADAMTS13 activity (undetectable or detectable). Clinical presentation, laboratory values, autoimmune manifestations, and outcome were compared between the groups. Patients were included retrospectively from 12 centers. All fulfilled the diagnosis criteria of TMA. Patients with a history of transplantation, cancer and chemotherapy, and Centers for Disease Control and Prevention (CDC) stage C human immunodeficiency virus (HIV) infection were not included. Forty-six patients were included. Thirty-one patients had an undetectable ADAMTS13 activity (<5%), and the remaining 15 patients had ADAMTS13 activity of >25%. Severe ADAMTS13 deficiency was associated with a plasmatic inhibitor in 17 cases (55%), suggesting an immune-mediated mechanism. Patients with undetectable ADAMTS13 were more frequently of Afro-Caribbean origin than patients with detectable ADAMTS13 activity (48.4% vs 13.3%, respectively; p = 0.03). As opposed to patients with detectable ADAMTS13 activity, patients with severe ADAMTS13 deficiency displayed various autoimmune manifestations that consisted of nondestructive polyarthritis (4 cases) associated in 1 case with malar rash and extramembranous glomerulonephritis, discoid lupus (3 cases), and autoimmune endocrinopathies, Raynaud phenomenon, and sarcoidosis-like disease (1 case each). In patients with severe ADAMTS13 deficiency, antinuclear antibodies, anti-double-stranded DNA antibodies, and anticardiolipin antibodies were positive in 22 (71%) cases, 3 (9.7%) cases, and 1 (3.2%) case, respectively. One patient fulfilled the criteria for the diagnosis of systemic lupus erythematosus. During follow-up, 1 patient with severe ADAMTS13 deficiency developed antinuclear antibodies, and 3 others developed anti-double-stranded DNA antibodies, in association with neurologic manifestations and anticardiolipin antibodies in 1 case. Patients with severe ADAMTS13 deficiency also had a lower platelet count (12 x 10(9)/L; range, 2-69 x 10(9)/L) and less severe renal failure (estimated glomerular filtration rate: 78 mL/min; range, 9-157 mL/min) than patients with detectable ADAMTS13 activity (49.5 x 10(9)/L; range, 6-103 x 10(9)/L; p = 0.0004, and 15.8 mL/min; range, 5.6-80 mL/min; p < 0.0001, respectively). End-stage renal failure occurred in 1 patient with severe ADAMTS13 deficiency and in 3 patients with detectable ADAMTS13 activity (3.2% vs 21.4%, respectively; p = 0.08). Flare-up and relapse episodes and survival were comparable between the groups. Taken together, these data indicate that adult idiopathic thrombotic thrombocytopenic purpura, as defined by severe ADAMTS13 deficiency, may occur preferentially in a particular ethnic group, and is characterized by severe thrombocytopenia, mild renal involvement, and a wide spectrum of autoimmune manifestations that may be completed during follow-up. Indeed, apparently idiopathic thrombotic thrombocytopenic purpura may be considered a specific autoimmune disease.
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PMID:Severe ADAMTS13 deficiency in adult idiopathic thrombotic microangiopathies defines a subset of patients characterized by various autoimmune manifestations, lower platelet count, and mild renal involvement. 1523 11

Thrombotic microangiopathy, which includes thrombotic thrombocytopenic purpura (TTP), shiga-toxin-associated hemolytic uremic syndrome (Stx-HUS) and atypical HUS, is characterized by the development of hyaline thrombi in the microvasculature resulting in thrombocytopenia, microangiopathic hemolysis, and organ dysfunction. Renal failure is a predominant complication of both Stx-HUS and atypical HUS, whereas neurological complications are more prominent in TTP. Other disorders such as lupus or bone marrow transplantations may occasionally present with features of thrombotic microangiopathy. Recent studies have found autoimmune inhibitors or genetic mutations of a von Willebrand factor (VWF) cleaving metalloprotease ADAMTS13 in patients with TTP. In approximately 30-50% of patients with atypical HUS, mutations have been detected in complement factor H, membrane cofactor protein (CD46), or factor I. All three proteins are involved in the regulation of complement activation. Additionally, autoantibodies of factor H have been described in patients without genetic mutations. These advances illustrate that dysregulation of VWF homeostasis or complement activation owing to genetic or autoimmune mechanisms may lead to the syndrome of thrombotic microangiopathy.
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PMID:The molecular biology of thrombotic microangiopathy. 1676 Sep 11

Thrombotic thrombocytopenic purpura (TTP) is a rare but frequently fatal complication of SLE. It occurs in the context of both active and inactive lupus and carries a worse overall prognosis than idiopathic acquired TTP. Recent advances in the knowledge and treatment of TTP do not seem to have brought similar improvements in the management and outcome of TTP in SLE. The illumination of the role of the von Willebrand factor multimer protease, ADAMTS13 in idiopathic TTP continues to enhance our comprehension of the pathogenesis of the disease and has contributed to improvements in diagnosis and management. We explore the overlap of TTP and SLE, and discuss the current understanding of the involvement of ADAMTS13 and its implications for patients with this uncommon form of microangiopathic haemolytic anaemia.
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PMID:Microangiopathic haemolytic anaemia resembling thrombotic thrombocytopenic purpura in systemic lupus erythematosus: the role of ADAMTS13. 2114 42

Severe manifestations of systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS), and thrombotic thrombocytopenic purpura (TTP) are characterized by multiorgan thrombotic microangiopathy. We describe reduction of ADAMTS13 activity and the development of systemic autoimmunity in all 8 children initially diagnosed with acquired noncongenital TTP during an 8.5-year period. Median age at diagnosis was 12.0 years (range, 2.6-17.3 years). ADAMTS13 activity was absent (<5%) in 6 patients; 3 patients had a detected inhibitor. SLE was diagnosed concurrently in 3 patients, and 4 patients were diagnosed within 5 years. Six of the children diagnosed with SLE had absent ADAMTS13 activity at diagnosis. In 6 patients with SLE, immune-mediated nephritis developed by 46 months. All surviving patients with SLE developed antiphospholipid antibodies, including some with a lupus anticoagulant. Patients with SLE did not have TTP recurrences once daily immunosuppressive regimens were started. An evaluation for SLE/APS is warranted in children and adolescents with reduced ADAMTS13 activity and thrombotic microangiopathy.
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PMID:Thrombotic microangiopathic hemolytic anemia with reduction of ADAMTS13 activity: initial manifestation of childhood-onset systemic lupus erythematosus. 2191 91

Recently reported cases of lupus complicated by a thrombotic thrombocytopenic purpura (TTP)-like syndrome suggest a survival benefit to early treatment with plasma exchange. The following is a report of the eighth such case in the last ten years. A 44-year-old lady known for lupus presented with the nephrotic syndrome and a renal biopsy was consistent with class 4G lupus nephritis. She was given high-dose steroids and cytotoxic therapy, but her induction therapy was complicated by the classic pentad of TTP. She was subsequently treated with another course of high-dose steroids, a different cytotoxic agent, and plasma exchange, with clinical resolution shortly thereafter. Similar to seven recently reported cases of microangiopathy in lupus, this lady's TTP-like syndrome improved dramatically after initiation of plasma exchange, despite not having a severely deficient ADAMTS13. This has implications on both current clinical practice and on the pathogenesis of TTP-like syndromes in lupus.
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PMID:Lupus-associated thrombotic thrombocytopenic purpura-like microangiopathy. 2655 90

Thrombotic thrombocytopenic purpura (TTP) is a multisystem disorder characterized by microvascular aggregation of platelets and fibrin strands causing thrombocytopenia, microangiopathic hemolytic anemia, and organ dysfunction. TTP can develop as a result of a deficiency in ADAMTS13 enzyme activity due to either a genetic defect or, more commonly, the development of anti-ADAMTS13 autoantibodies. TTP can also be associated with pregnancy, organ transplant, lupus, infections, and drugs. Here, we present a case of TTP that developed shortly after the start of clopidogrel treatment for acute ischemic stroke and acute myocardial infarction, and describe the clinical presentation, refractory course of the disease, and successful induction of remission through the use of rituximab in a setting of pre-existing autoimmune diseases.
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PMID:Clopidogrel-induced refractory thrombotic thrombocytopenic purpura successfully treated with rituximab. 2668 18

Antiphospholipid syndrome (APS) is an autoimmune disease in which antiphospholipid antibodies (aPLs) are generated. Previous studies show concurrence of APS and thrombotic thrombocytopenic purpura; therefore it is plausible to assume that anti-ADAMTS13 autoantibody is also involved in the pathophysiology of APS. We investigated the clinical significance of ADAMTS13 activity and anti-ADAMTS13 antibody in patients with aPLs. Two hundred and sixteen patients with positive lupus anticoagulant and/or anticardiolipin antibody were included. ADAMTS13 activity and anti-ADAMTS13 antibody were measured using fluorescence resonance energy-transfer technology and ELISA, respectively. Reduced ADAMTS13 activity was observed in 40.3% (87/216) of patients with aPLs. Although 33.8% (73/216) of patients were positive for anti-ADAMTS13 antibody, 41 of these 73 patients had normal levels of ADAMTS13 activity. Reduced ADAMTS13 activity was a significant risk factor for thrombotic events. Thrombotic events and age contributed to the reduced level of ADAMTS13 activity. Presence of anti-ADAMTS13 antibody did not show any association with the level of ADAMTS13 activity. Patients with autoimmune diseases tended to show higher levels of anti-ADAMTS13 antibody. Our findings suggest that reduced ADAMTS13 activity is a significant thrombotic risk factor in patients with aPLs irrespective of the presence of anti-ADAMTS13 antibody. Presence of anti-ADAMTS13 antibody is not seen with reduced activity and it tends to be increased in patients with autoimmune diseases.
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PMID:Thrombotic risk of reduced ADAMTS13 activity in patients with antiphospholipid antibodies. 2675 14

BACKGROUND Thrombotic thrombocytopenic purpura (TTP) is one of the thrombotic microangiopathic (TMA) syndromes, caused by severely reduced activity of the vWF-cleaving protease ADAMTS13. Systemic lupus erythematosus (SLE), on the other hand, is an autoimmune disease that affects various organs in the body, including the hematopoietic system. SLE can present with TMA, and differentiating between SLE and TTP in those cases can be very challenging, particularly in patients with no prior history of SLE. Furthermore, an association between these 2 diseases has been described in the literature, with most of the TTP cases occurring after the diagnosis of SLE. In rare cases, TTP may precede the diagnosis of SLE or occur concurrently. CASE REPORT We present a case of a previously healthy 34-year-old female who presented with dizziness and flu-like symptoms and was found to have thrombocytopenia, hemolytic anemia, and schistocytes in the peripheral smear. She was subsequently diagnosed with TTP and started on plasmapheresis and high-dose steroids, but without a sustained response. A diagnosis of refractory TTP was made, and she was transferred to our facility for further management. Initially, the patient was started on rituximab, but her condition continued to deteriorate, with worsening thrombocytopenia. Later, she also fulfilled the Systemic Lupus International Collaborating Clinics (SLICC) criteria for diagnosis of SLE. Treatment of TTP in SLE patients is generally similar to that in the general population, but in refractory cases there are few reports in the literature that show the efficacy of cyclophosphamide. We started our patient on cyclophosphamide and noticed a sustained improvement in the platelet count in the following weeks. CONCLUSIONS Thrombotic thrombocytopenic purpura is a life-threatening hematological emergency which must be diagnosed and treated in a timely manner. Refractory cases of TTP have been described in the literature, but without clear evidence-based guidelines for its management, and is solely based on expert opinion and previous case reports. Further studies are needed to establish guidelines for its management. We present this case to highlight the role that cyclophosphamide might carry in those cases and to be a foundation for these future studies.
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PMID:Systemic Lupus Erythematosus Presenting as Refractory Thrombotic Thrombocytopenic Purpura: A Diagnostic and Management Challenge. A Case Report and Concise Review of the Literature. 2777 94