Thrombotic microangiopathic hemolytic anemia with reduction of ADAMTS13 activity: initial manifestation of childhood-onset systemic lupus erythematosus

Dysregulated endothelial cell markers in systemic lupus erythematosus: a systematic review and meta-analysis

OBJECTIVES

To perform a systematic literature review and meta-analysis on endothelial cell (EC) markers that are involved and dysregulated in systemic lupus erythematosus (SLE) in relation to disease activity, as EC dysregulation plays a major role in the development of premature atherosclerosis in SLE.

METHODS

Search terms were entered into Embase, MEDLINE, Web of Science, Google Scholar and Cochrane. Inclusion criteria were 1) studies published after 2000 reporting measurements of EC markers in serum and/or plasma of SLE patients (diagnosed according to ACR/SLICC criteria), 2) English language peer reviewed articles, and 3) disease activity measurement. For meta-analysis calculations, the Meta-Essentials tool by Erasmus Research Institute and of Management (ERIM) was used. Only those EC markers, which were 1) reported in at least two articles and 2) reported a correlation coefficient (i.e. Spearman's rank or Pearson's) between the measured levels of the EC marker and disease activity were included. For meta-analyses, a fixed effect model was used.

RESULTS

From 2133 hits, 123 eligible articles were selected. The identified SLE-related endothelial markers were involved in EC activation, EC apoptosis, disturbed angiogenesis, defective vascular tone control, immune dysregulation and coagulopathy. Meta-analyses of primarily cross-sectional studies showed significant associations between marker levels and disease activity for the following endothelial markers: Pentraxin-3, Thrombomodulin, VEGF, VCAM-1, ICAM-1, IP-10 and MCP-1. Dysregulated EC markers without associations with disease activity were: Angiopoeitin-2, vWF, P-Selectin, TWEAK and E-Selectin.

CONCLUSIONS

We provide a complete literature overview for dysregulated EC markers in SLE comprising a wide range of different EC functions. SLE-induced EC marker dysregulation was seen with, but also without, association with disease activity. This study provides some clarity in the eminent complex field of EC markers as biomarkers for SLE. Longitudinal data on EC markers in SLE are now needed to guide us more in unravelling the pathophysiology of premature atherosclerosis and cardiovascular events in SLE patients.

Case report: Thrombotic microangiopathy concomitant with macrophage activation syndrome in systemic lupus erythematosus refractory to conventional treatment successfully treated with eculizumab

Thrombotic microangiopathy (TMA) is a rare but life-threatening complication of systemic lupus erythematosus (SLE). Macrophage activation syndrome (MAS) is also a rare, life-threatening hyperinflammatory condition that is comorbid with SLE. However, the association between TMA and MAS in patients with SLE has rarely been assessed, and the difficulty of diagnosing these conditions remains prevalent. The efficacy of eculizumab has been reported for SLE patients whose conditions are complicated with TMA. However, no study has investigated the therapeutic efficacy of eculizumab for TMA concomitant with SLE-associated MAS. Herein, we report the first case of TMA concomitant with SLE-associated MAS that was initially refractory to conventional immunosuppressive therapy but showed remarkable recovery after eculizumab treatment. Furthermore, we evaluated serum syndecan-1 and hyaluronan levels, which are biomarkers of endothelial damage. We found that these levels decreased after the administration of eculizumab, suggesting that TMA was the main pathology of the patient. This case illustrates that it is important to appropriately assess the possibility of TMA during the course of SLE-associated MAS and consider the use of eculizumab as necessary.

Thrombotic Microangiopathy Associated with Macrophage Activation Syndrome: A Multinational Study of 23 Patients

OBJECTIVE

To describe the clinical characteristics, treatment, and outcomes of a multinational cohort of patients with macrophage activation syndrome (MAS) and thrombotic microangiopathy (TMA).

STUDY DESIGN

International pediatric rheumatologists were asked to collect retrospectively the data of patients with the co-occurrence of MAS and TMA. Clinical and laboratory features of patients with systemic juvenile idiopathic arthritis (sJIA)-associated MAS and TMA were compared with those of an historical cohort of patients with sJIA and MAS.

RESULTS

Twenty-three patients with MAS and TMA were enrolled: 17 had sJIA, 2 systemic lupus erythematosus, 1 juvenile dermatomyositis, 1 mixed connective tissue disease, and 2 undifferentiated connective tissue disease. Compared with the historical cohort of MAS, patients with sJIA with coexistent MAS and TMA had higher frequencies of renal failure and neurologic involvement, hemorrhage, jaundice, and respiratory symptoms, as well as more severe anemia and thrombocytopenia, higher levels of alanine aminotransferase, lactate dehydrogenase, bilirubin and D-dimer, and lower levels of albumin and fibrinogen. They also required admission to the intensive care unit more frequently. Among patients tested, complement abnormalities and reduced ADAMTS13 activity were observed in 64.3% and 44.4% of cases, respectively. All patients received glucocorticoids. Treatment for TMA included plasma-exchange, eculizumab, and rituximab.

CONCLUSIONS

The possible coexistence of MAS and TMA in rheumatic diseases may be underrecognized. This association should be considered in patients with MAS who develop disproportionate anemia, thrombocytopenia, and lactate dehydrogenase increase, or have multiorgan failure.

Microvascular thrombosis: experimental and clinical implications

A significant amount of clinical and research interest in thrombosis is focused on large vessels (eg, stroke, myocardial infarction, deep venous thrombosis, etc.); however, thrombosis is often present in the microcirculation in a variety of significant human diseases, such as disseminated intravascular coagulation, thrombotic microangiopathy, sickle cell disease, and others. Further, microvascular thrombosis has recently been demonstrated in patients with COVID-19, and has been proposed to mediate the pathogenesis of organ injury in this disease. In many of these conditions, microvascular thrombosis is accompanied by inflammation, an association referred to as thromboinflammation. In this review, we discuss endogenous regulatory mechanisms that prevent thrombosis in the microcirculation, experimental approaches to induce microvascular thrombi, and clinical conditions associated with microvascular thrombosis. A greater understanding of the links between inflammation and thrombosis in the microcirculation is anticipated to provide optimal therapeutic targets for patients with diseases accompanied by microvascular thrombosis.

Successful treatment of refractory thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus with combination of plasma exchange and low-dose rituximab

OBJECTIVES

Thrombotic thrombocytopenia purpura (TTP) associated with systemic lupus erythematous (SLE) (i.e., SLE-TTP) is a rare life-threatening disease often requiring intensive immunosuppressive agents, in addition to high-dose corticosteroids and plasma exchange (PEX). The optimal therapy of rituximab is unclear, but 375 mg/m² weekly for 4 weeks is the usual practice, adopted from regimens for non-Hodgkin's lymphoma. We reported two cases of refractory SLE-TTP that showed good efficacy and prognosis with combination of methylprednisolone (MP) pulse, plasma exchange and low-dose rituximab (100 mg weekly for 4 weeks) treatment.

METHODS

Clinical data and treatment outcomes were reviewed of two patients diagnosed with refractory SLE-TTP at Peking Union Medical College Hospital between July 2017 and July 2018.

RESULTS

Both patients had SLE and presented with microangiopathic anemia and thrombocytopenia. Laboratory assays revealed high anti-nuclear antibody titers, reduced complement 3 and 4 levels, proteinuria, significantly elevated lactate dehydrogenase, schistocytes on peripheral blood smear, low ADAMTS13 activity, and the presence of ADAMTS13 inhibitor. In both patients, platelet counts remained below 50 × 10⁹/L after MP pulse and 6 PEXs, confirming the diagnosis of refractory SLE-TTP. Low-dose rituximab (100 mg weekly for 4 weeks) was administered in both cases, resulting in normalization of platelet counts and significant reductions in B-lymphocyte counts. No TTP relapse or SLE flare occurred during 24 months of follow-up.

CONCLUSIONS

Our cases confirmed the efficacy and good follow-up outcomes of low-dose rituximab treatment (100 mg weekly for 4 weeks) for refractory SLE-TTP.

Thrombotic risk of reduced ADAMTS13 activity in patients with antiphospholipid antibodies

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.

Antiphospholipid syndrome in renal transplantation

Antiphospholipid syndrome (APS) may occur in isolation or in association with systemic lupus erythematosus (SLE), with the potential to cause renal failure via several distinct pathologies. Renal transplantation in the presence of APS carries a risk of early graft loss from arterial or venous thrombosis, or thrombotic microangiopathy (TMA). Whilst perioperative anticoagulation reduces the risk of large vessel thrombosis, it may result in significant haemorrhage, and its efficacy in preventing post-transplant TMA is uncertain. Here, we report a patient with end-stage kidney disease (ESKD) due to lupus nephritis and APS, in whom allograft TMA developed soon after transplantation despite partial anticoagulation. TMA resolved with plasma exchange-based therapy albeit with some irreversible graft damage and renal impairment. We discuss the differential diagnosis of post-transplant TMA, and current treatment options.

Cryosupernatant and Immunosuppression as Effective Alternative Therapies for TTP in Three Pediatric SLE Patients

Thrombotic thrombocytopenic purpura (TTP) and systemic lupus erythematosus (SLE) very rarely present simultaneously and pose a diagnostic and therapeutic dilemma to the physician. Prompt diagnosis and management with plasma exchange and immunosuppression is life-saving. To describe the effectiveness of cryosupernatant and steroids in pediatric SLE with TTP. We describe three children aged 12-14 years with SLE who were diagnosed with TTP based on fever, CNS manifestations, ANA, anti-dsDNA, anti-sm positivity, hypocomplementemia, and microangiopathic anemia with thrombocytopenia. All three children were managed with cryosupernatant and steroids without plasmapheresis. All children improved with cryosupernatant and steroids. All attained remission within 10 days. They were doing well at last follow up without relapse or flare. Cryosupernatant and steroids may be an effective therapy for Thrombotic thrombocytopenic purpura with systemic lupus erythematosus.

Children and adults with thrombotic thrombocytopenic purpura associated with severe, acquired Adamts13 deficiency: comparison of incidence, demographic and clinical features

BACKGROUND

Thrombotic thrombocytopenic purpura (TTP) associated with severe, acquired ADAMTS13 deficiency is uncommonly reported in children. The incidence, demographic, and clinical features of these children, compared to adults, have not been described.

PROCEDURES

This study focused on children (<18 years old) and adults with TTP associated with severe, acquired ADAMTS13 deficiency, defined as activity <10%. The incidence rates for TTP in children and adults were calculated from patients enrolled in the Oklahoma TTP-HUS (Hemolytic-Uremic syndrome) Registry, 1996-2012. To describe demographic and clinical features, children with TTP were also identified from a systematic review of published reports and from samples sent to a reference laboratory for analysis of ADAMTS13.

RESULTS

The standardized annual incidence rate of TTP in children was 0.09 × 10(6) children per year, 3% of the incidence rate among adults (2.88 × 10(6) adults per year). Among the 79 children who were identified (one from the Oklahoma Registry, 55 from published reports, 23 from the reference laboratory), TTP appeared to be more common among females, similar to the relative increased frequency of women among adults with TTP, and more common in older children. Clinical data were available on 52 children; the frequency of severe renal failure, relapse, treatment with rituximab, and systemic lupus erythematosus in these children was similar to adults with TTP.

CONCLUSIONS

TTP associated with severe, acquired ADAMTS13 deficiency is uncommon in children. The demographic and clinical features of these children are similar to the features of adults with TTP.

Kidney-limited thrombotic microangiopathy in patients with SLE treated with romiplostim

We present the case of a 19 year-old Caucasian female with history of systemic lupus erythematosus (SLE) and normal baseline kidney function who developed severe acute renal failure following treatment of thrombocytopenia with the thrombopoietic agent romiplostim. Percutaneous kidney biopsy revealed thrombotic microangiopathy (TMA) without immune complex lupus glomerulonephritis. We discuss pathogenesis and differential diagnosis of TMA in patients with SLE and raise concerns regarding the use of thrombopoietic agents in such patients. Based on favorable long-term outcome in our case aggressive treatment and in particular prolonged use of plasma exchange in these patients are advocated.

Nitrofurantoin-induced microangiopathic haemolytic anaemia and thrombocytopaenia in a patient with systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) may develop thrombotic thrombocytopaenic purpura (TTP) or TTP-like illness manifested by microangiopathic haemolytic anaemia (MAHA) and thrombocytopaenia. The distinction between active SLE and TTP is difficult because these entities share similar clinical features. Drug-induced TTP caused by an immune-mediated reaction have been documented for several drugs. Herein, we report a middle-aged Hispanic woman with long-standing SLE, who developed a TTP-like illness characterised by MAHA and thrombocytopaenia after exposure to nitrofurantoin. The patient responded well to plasmapheresis and immunosuppressive therapy and has remained clinically stable after 18&emsp14;months of follow-up. To our knowledge, this is the first case that reports the association between nitrofurantoin and a TTP-like presentation.

Hematological features of pediatric systemic lupus erythematosus: suggesting management strategies in children

Aim: The aim of this study was to analyze the hematological features in children with systemic lupus erythematosus (SLE) and to review our current treatment protocols. Methods: We evaluated hematological findings of 43 children with SLE diagnosed and followed at the Pediatric Rheumatology Division of Hacettepe University, Turkey. Thirty-seven patients with hematological abnormalities were analyzed in detail. Results: Median age at presentation was 13 years. Hematological involvement was seen in 86% of patients. The most common hematological finding was anemia ( n = 30). Anemia was either a Coombs (+) hemolytic one, or was due to other causes. Hemolytic anemia was treated with steroids and intravenous gamma globulin (IVIG). Leucopenia and thrombocytopenia were detected in 35.1 % and 37.8 %, respectively. Bone marrow aspiration was performed in 15, mainly for cytopenia. Secondary dysplastic changes were common. Acute lymphoblastic leukemia (ALL) was diagnosed in one patient. Six patients were diagnosed as having macrophage activation syndrome (MAS). One patient died due to secondary infections and multiorgan failure despite aggressive treatment. In patients diagnosed early, treatment with steroids and cyclosporine resulted in an excellent response. Thrombotic microangiopathy was detected in two patients. Both were treated successfully with steroids and plasma exchange. Antiphospholipid and anticardiolipin antibodies were positive in 12 and 15 of the patients, respectively. Five developed deep vein thrombosis (DVT), one cerebral sinus thrombosis and one presented with purpura fulminans. They were effectively treated with anticoagulation protocol. Conclusion: Hematological findings should be carefully assessed and treated vigorously to prevent the morbidity and possible mortality.

Thrombotic microangiopathy due to multiple autoantibodies related to antiphospholipid syndrome

BACKGROUND

Antiphospholipid syndrome (APS) is a rare disorder in children. More than half of childhood APS occurs as secondary APS complicated by systemic lupus erythematosus (SLE) and other autoimmune diseases.

CASE-DIAGNOSIS/TREATMENT

We encountered a boy with SLE who presented with thrombotic microangiopathy (TMA) due to APS. He was initially diagnosed with SLE and treated with methylprednisolone pulse therapy. However, his renal function rapidly deteriorated. Since poikilocytes were detected, we suspected that his condition was complicated by TMA or APS. Urgent plasma exchange, continuous hemodialysis, and intravenous cyclophosphamide saved the patient and his renal failure ameliorated. A renal biopsy performed at the onset of disease showed multiple microvascular thrombi, diffuse mesangiolysis, and cortical necrosis compatible with TMA. He was positive for anticardiolipin antibody, anti-β2-glycoprotein I antibody, and lupus anticoagulant as well as anti-phosphatidylserine-prothrombin complex IgG antibody (aPS/PT). Anti-a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS13) antibody was negative and ADAMTS13 activity was normal. The aPS/PT is thrombogenic and is a newly discovered lupus anticoagulant.

CONCLUSIONS

Childhood TMA due to APS has rarely been reported. To the best of our knowledge this is the first report of pediatric TMA due to APS with positive aPS/PT. Physicians need to be aware of aPS/PT in pediatric APS and/or SLE.