Microangiopathic haemolytic anaemia resembling thrombotic thrombocytopenic purpura in systemic lupus erythematosus: the role of ADAMTS13

Two pregnant women with immune-mediated thrombotic thrombocytopenic purpura: A case report

Thrombotic thrombocytopenic purpura (TTP) during pregnancy is life-threatening. We encountered two pregnant women with immune-mediated TTP (iTTP). A 40-year-old primigravida woman was referred at 19 gestational weeks (GWs) owing to iTTP. She received plasma exchange (PE) and steroid therapies and delivered a live infant at 27 GWs by cesarean delivery. A 29-year-old primigravida woman was referred owing to intrauterine fetal death and thrombocytopenia at 20 GWs. She was diagnosed with iTTP and received PE therapy. She required additional PE and steroid therapies owing to relapse. Before her second pregnancy, she received prednisolone and hydroxychloroquine according to the therapy for systemic lupus erythematosus (SLE). She had induced labor at 37 GWs owing to decrease plasma level of a disintegrin-like and metalloproteinase with thrombospondin type 1 motif 13 (ADAMTS13) activity. Close monitoring of plasma ADAMTS13 activity level and treatments for underlying SLE may prevent iTTP relapse and lead to a good prognosis.

Traversing Their Path to the Peripheral Smear: The Journey of Traumatized Red Blood Cells

Background  Thrombotic microangiopathy encompasses a wide range of conditions, of which thrombotic thrombocytopenic purpura being a medical emergency requires prompt intervention, with schistocytes being a reliable morphological indicator of microvascular injury. However, there are conditions other than thrombotic microangiopathic anemia where schistocytes can be seen in large numbers. These nonthrombotic microangiopathic conditions are broadly grouped under cytoskeletal abnormalities, mechanical damage, and thermal injuries. Automated methods in schistocyte evaluation have shown varied reproducibility requiring manual identification. International Council for Standardization in Hematology (ICSH) recommends standardized morphological criteria and quantitative assessment as a percentage after counting at least 1,000 red blood cells in optimal areas of smear to reduce interobserver variability. Objectives  The aim of this study was to evaluate and quantitate schistocytes in thrombotic microangiopathic and nonthrombotic microangiopathic groups using ICSH guidelines and to evaluate interobserver reproducibility of manual schistocyte count. Materials and Methods  Overall, 157 peripheral blood smears showing schistocytes were studied by two independent observers using ICSH recommendations on light microscopy. The hematological findings were correlated with clinical diagnosis and other relevant investigations. Results  Schistocytes were observed in five cases of thrombotic microangiopathic anemia and 152 cases of nonthrombotic microangiopathic anemia. Schistocyte count in thrombotic microangiopathic anemia and nonthrombotic microangiopathic anemia groups with mean (±standard deviation) value was 2.28 ± 2.65% and 0.76 ± 0.67%, respectively ( p  < 0.001). The correlation coefficient between the two observers was 0.59 (confidence interval = 0.966-1.346) showing an excellent agreement on the reproducibility of schistocytes by application of ICSH guidelines. Conclusion  Percentage of schistocytes more than 1% is a robust morphological indicator for diagnosis of thrombotic microangiopathic anemia in adults. Strict application of ICSH guidelines reduces interobserver bias.

Upfront rituximab therapy for thrombotic thrombocytopenic purpura in systemic lupus erythematosus: a case-based review

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of various autoantibodies and deposition of immune complexes on tissues. Acquired thrombotic thrombocytopenic purpura (TTP) is a life-threatening hematological disorder that rarely develops in SLE, mainly caused by inhibitory or clearing autoantibody against ADAMTS13. Although B cells play critical roles in the pathogenesis of two diseases, the role of B-cell depletion therapy using rituximab (RTX), a chimeric monoclonal antibody targeting CD20, in the management of TTP associated with SLE remains unclear. We present a 27-year-old woman who manifested TTP and nephritis simultaneously at diagnosis of SLE. This patient successfully responded to high-dose glucocorticoids combined with plasma exchange, and early administration of RTX-induced sustained remission of TTP without relapse over 16 months. This literature review in light of our case demonstrates relationship between early intervention with RTX and better treatment response despite the degree of ADAMTS13 activity. Moreover, we discuss the clinical features in TTP associated with SLE, risk factors for the development of TTP in SLE, and possible outcomes based on RTX dose. It is important to consider upfront RTX as a promising treatment strategy for SLE-associated secondary TTP to improve short-term response and long-term prognosis.

Characteristics and genetic analysis of patients suspected with early-onset systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) is rarely diagnosed before 5-years-old. Those with disease onset at a very young age are predicted by a higher genetic risk and a more severe phenotype. We performed whole-exome sequencing to survey the genetic etiologies and clinical manifestations in patients fulfilling 2012 SLICC SLE classification criteria before the age of 5.

CASE PRESENTATION

Among the 184 childhood-onset SLE patients regularly followed in a tertiary medical center in Taiwan, 7 cases (3.8%) of which onset ≦ 5 years of age were identified for characteristic review and genetic analysis. Compared to those onset at elder age, cases onset before the age of 5 are more likely to suffer from proliferative glomerulonephritis, renal thrombotic microangiopathy, neuropsychiatric disorder and failure to thrive. Causative genetic etiologies were identified in 3. In addition to the abundance of autoantibodies, patient with homozygous TREX1 (c.292_293 ins A) mutation presented with chilblain-like skin lesions, peripheral spasticity, endocrinopathy and experienced multiple invasive infections. Patient with SLC7A7 (c.625 + 1 G > A) mutation suffered from profound glomerulonephritis with full-house glomerular deposits as well as hyperammonemia, metabolic acidosis and episodic conscious disturbance. Two other cases harbored variants in lupus associating genes C1s, C2, DNASE1 and DNASE1L3 and another with CFHR4. Despite fulfilling the classification criteria for lupus, many of the patients required treatments beyond conventional therapy.

CONCLUSIONS

Genetic etiologies and lupus mimickers were found among a substantial proportion of patients suspected with early-onset SLE. Detail clinical evaluation and genetic testing are important for tailored care and personalized treatment.

Case Report: Systemic lupus erythematous associated with thrombotic thrombocytopenic purpura, a diagnostic challenge

Thrombotic thrombocytopenic purpura (TTP) is an uncommon microangiopathic disease and sometimes is associated with systemic lupus erythematous (SLE). However, this probable causal relationship has not been completely proven. The diagnostic differentiation of both diseases is difficult in the first instance because they share similar characteristics that may overlap. We present a case of a 32-year-old woman with antecedents of epileptic seizures since she was 12 years old. The patient was admitted to the emergency room with a clinical picture of headaches, fever, paleness in the skin and mucosa, confused state, paresthesia, and transient spasticity of the extremities. The laboratory results revealed direct Coombs negative hemolytic anemia, severe thrombocytopenia, significant elevation of lactate dehydrogenase, and presence of schistocytes ++ in the peripheral film. In addition, positive antinuclear antibodies and positive anti-native DNA in titers of 1/320 and 1/160, respectively, were found. Urinalysis showed that serum creatinine was in normal range. Because of limited hospital resources, ADAMTS13 was not evaluated. However, based on clinical, hematological, and biochemical findings, we concluded that it was a case of TTP associated with SLE and indicated treatment with plasmapheresis and methylprednisolone pulses, obtaining a satisfactory response (normalization of biomarker levels, health condition) after the second session of plasmapheresis. Diagnosis of both SLE and TTP is often difficult to achieve; however, adequate correlation of clinical manifestations and laboratory tests, along with the help of partial therapeutic interventions, may lead to good clinical response.

Response to belimumab in thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus: a case-based review

Thrombotic thrombocytopenic purpura (TTP), a life-threatening syndrome characterized by acute microangiopathic hemolytic anemia, thrombocytopenia, and visceral ischemia, can be classified as congenital TTP (inherited due to a mutation in ADAMTS13) and acquired TTP. The acquired TTP is further classified as idiopathic and secondary TTP. Systemic lupus erythematosus (SLE) is regarded as one of the most common causes of secondary TTP (SLE-TTP). In contrast to patients with idiopathic TTP, some patients with SLE-TTP, especially those diagnosed with refractory TTP, are resistant to plasma exchange and high-dose corticosteroids and usually require second-line drugs, including newly developed biologicals. Belimumab, a B-lymphocyte stimulator-specific inhibitor, was the first approved new therapy for SLE in the past 50 years. Only two cases of SLE-TTP using belimumab have been reported; however, detailed information has not been made available. Herein, we describe a 28-year-old female patient who presented with palm petechiae, strong tawny urine, and yellow stained skin and sclera, and was diagnosed with SLE-TTP supported by high anti-ANA titers; positive anti-SSA/SM; pleural effusion; decreased platelet count, hemoglobin, and complement C3/C4 counts; increased lactate dehydrogenase level, along with increased schistocytes; and a significant deficiency of ADAMTS13 activity. Belimumab (10 mg/kg) was administered after six plasma exchanges. Good efficiency and outcomes without any adverse events, SLE, or TTP relapse were observed during 12 months of follow-up. Therefore, belimumab is a promising choice for SLE-TTP management. In addition, we provide a focused review of the existing literature on the pathogenesis, diagnosis, and therapeutic strategies for SLE-TTP.

Successful preventive treatment with cyclosporine in a patient with relapsed/refractory immune-mediated thrombotic thrombocytopenic purpura: a case report and review of the literature

Although salvage therapy with rituximab is effective in some cases of immune-mediated thrombotic thrombocytopenic purpura (iTTP) refractory to standard plasma exchange (PEX) and glucocorticoid treatment or relapsed after treatment, protocols to address the subsequent high recurrence rate have not been established. We describe the use of cyclosporine (CSA) to prevent recurrence in a patient with iTTP relapse after rituximab therapy, and present a literature review. A 24-year-old woman was diagnosed with iTTP and initially received PEX and high-dose methylprednisolone therapy. However, weekly rituximab therapy was also needed for inhibitor boosting to achieve additional immunosuppression during the initial treatment. Although the patient achieved clinical remission after weekly rituximab therapy, iTTP relapsed twice when glucocorticoids were tapered, and was treated with a triplet regimen consisting of PEX, high-dose methylprednisolone, and weekly rituximab. CSA was administered along with glucocorticoids as prophylaxis against iTTP relapse. The additional CSA therapy successfully maintained iTTP remission and allowed reduction of the corticosteroid dose. Our findings demonstrate that prophylactic CSA can potentially prevent iTTP recurrence in patients with a history of multiple relapses. Data from more cases must be accumulated to establish a useful prophylactic therapy for iTTP that is refractory even to rituximab.

Management of Severe Refractory Systemic Lupus Erythematosus: Real-World Experience and Literature Review

Systemic lupus erythematosus (SLE) is a highly heterogeneous disease affecting multiple organs and is characterized by an aberrant immune response. Although the mortality of SLE has decreased significantly since the application of glucocorticoids, severe or refractory SLE can potentially cause irreversible organ damage and contribute to the disease morbidity and mortality. Early recognition of severe SLE or life-threatening conditions is of great challenge to clinicians since the onset symptoms can be rapid and aggressive, involving the visceral organs of the neuropsychiatric, gastrointestinal, hematologic, renal, pulmonary, and cardiovascular systems, etc. Additionally, SLE patients with specific comorbidities and detrimental complications could lead to a clinical dilemma and contribute to poor prognosis. Prompt and adequate treatment for severe refractory SLE is crucial for a better prognosis. However, as evidence from well-designed randomized controlled trials is limited, this review aims to provide real-world evidence based on cohort studies from Peking Union Medical College Hospital, the national tertiary referral center in China, together with the literature, on clinical characteristics, risks and prognostic factors, and treatment strategies for severe and/or refractory SLE.

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.

A systematic review of the role of eculizumab in systemic lupus erythematosus-associated thrombotic microangiopathy

Background

Lupus nephritis (LN) is a severe consequence of systemic lupus erythematosus (SLE) that affects approximately 40% of patients. Pathogenic immune complexes that are characteristic of LN deposit in the kidney and activate immune mediated pathways including the complement system. Complete remission rates in LN are approximately 44% highlighting the need for new treatment strategies in these patients. Eculizumab is a fully humanised IgG2/IgG4 monoclonal antibody directed at C5 and thus prevents the formation of the terminal complement complex. Eculizumab is successfully used in atypical haemolytic uraemic syndrome (aHUS) and paroxysomal nocturnal haemoglobinuria (PNH) but it is not standardly used in LN. The aim of this project was to determine whether there is any role for eculizumab as adjunctive therapy in LN.

Methods

Using a predefined search strategy on Ovid MEDLINE and EMBASE the literature was reviewed systematically to identify studies in which eculizumab had been used to treat patients with SLE. All patients were included that were treated with complement inhibitors. Favourable outcome in this study was defined as resolution of symptoms that led to treatment, discharge from hospital or recovery of renal function. Patients were excluded if there was no outcome data or if complement inhibition was unrelated to their SLE.

Results

From 192 abstracts screened, 14 articles were identified, involving 30 patients. All SLE patients administered eculizumab were treated for thrombotic microangiopathy (TMA) secondary to LN diagnosed either histologically (66%) or as part of a diagnosis of aHUS (73%). 93% of patients had a favourable outcome in response to eculizumab treatment, of which 46% had a favourable outcome and successfully stopped treatment without relapse in symptoms during a median follow up of 7 months. Three patients (10%) reported adverse outcomes related to eculizumab therapy.

Conclusions

Scientific evidence supports the involvement of complement in the pathogenesis of LN however the role of complement inhibition in clinical practice is limited to those with TMA features. This systematic review showed that in cases of LN complicated with TMA, eculizumab seems to be a very efficacious therapy. Further evidence is required to determine whether patients with refractory LN may benefit from adjunctive complement inhibition.

An Autopsy Case of Mixed Connective Tissue Disease Complicated by Thrombotic Thrombocytopenic Purpura

We herein report a patient with mixed connective tissue disease (MCTD) who had been stable for years but suddenly developed thrombotic thrombocytopenic purpura (TTP). The patient showed a clinical pentad of signs of TTP, low activity of ADAMTS13, and positivity of anti-ADAMTS13 antibodies. She did not respond to plasma exchange or steroid therapy and died five days after admission. An autopsy revealed microthrombi in the brain, heart, kidney, adrenal glands, esophageal submucosa, and bone marrow as well as diffuse alveolar hemorrhaging. Physicians should bear in mind that TTP can occur in MCTD patients regardless of disease activity.

Managing pregnancy-associated clinical emergencies in systemic lupus erythematosus: a case-based approach

Introduction: Systemic lupus erythematosus (SLE)-related thrombocytopenia during pregnancy and the postpartum period have been associated with adverse pregnancy outcomes and perinatal complications. In this case report, we present two SLE patients with thrombocytopenia emergencies secondary to HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome and thrombotic thrombocytopenic purpura (TTP).Areas covered: The first case involved a 26-year-old woman, G1P0 at 26 weeks gestation (GA), with high-titer antiphospholipid antibodies (aPL) (positive lupus anticoagulant, anti-beta 2 glycoprotein-1 (aβ2GP1), anti-cardiolipin) and non-criteria aPL to phosphatidylserine/prothrombin complex and anti-domain 1 β2GP1. This case highlights the risks associated with aPL in pregnancy, considers management issues relating to anticoagulation during pregnancy and highlights the importance of maintaining a high index of suspicion for diagnosis of HELLP in SLE patients. The second case was a 36-year-old female, G3P2 at 32 weeks GA, with class III lupus nephritis (LN) who developed severe pre-eclampsia, which included mild thrombocytopenia. This case illustrates the challenges in identifying and differentiating between three pregnancy emergencies that can be seen in SLE patients (pre-eclampsia, LN, and TTP) and presents the management of TTP in peripartum SLE.Expert opinion: These two cases remind us of the importance of timely diagnosis and management of thrombocytopenia in this population.

Thrombotic Microangiopathies with Rheumatologic Involvement

Thrombotic microangiopathies are heterogeneous disorders characterized by microangiopathic hemolytic anemia with thrombocytopenia and renal injury. There are a variety of causes, including metabolic disorders, infections, medications, complement disorders, pregnancy, malignancy, and autoimmune disorders. This review focuses on renal thrombotic microangiopathy in the setting of rheumatologic diseases. Systemic lupus erythematosus is the most common autoimmune disease associated with thrombotic microangiopathy. Other etiologies include scleroderma renal crisis and antiphospholipid antibody syndrome, which can be primary or secondary to autoimmune diseases including systemic lupus erythematosus. There have also been case reports of thrombotic microangiopathy in the setting of rheumatoid arthritis and dermatomyositis.

Effect of Thrombotic Microangiopathy on Clinical Outcomes in Indian Patients With Lupus Nephritis

INTRODUCTION

In addition to glomerular lesion, renal vascular lesion is also an important prognostic marker of lupus nephritis (LN). Among patients with various vascular changes, individuals with thrombotic microangiopathy (TMA) present with severe clinical manifestations and have a high mortality. The aim of the present study was to assess the spectrum and impact of TMA on the outcomes of LN. In a prospective observational study of 2.5 years' duration, clinical and renal histopathological data regarding biopsy-proven LN were noted, and evaluation for antiphospholipid syndrome (APS) as a cause of TMA in LN was also carried out.

METHODS

Study subjects were followed up actively for 6 months, and various outcomes were noted. Cases were divided into 2 groups as LN with TMA and LN without TMA, and various features were compared between the 2 groups. Outcomes recorded were complete response (CR), partial response (PR), treatment failure, and death.

RESULTS

Of the 197 patients with LN, 50 patients (25.4%) were diagnosed with co-existing renal TMA. Five patients (10%) were found to have concomitant APS. As compared to patients without TMA, those with TMA had significantly higher rates of oliguria (P = 0.035), advanced renal injury, that is, serum creatinine > 3mg/dl (P = 0.002), fibrocellular and fibrous crescents (P = 0.01), and tubular atrophy (P = 0.001). Outcomes included CR in 15 patients (30%), PR in 10 (20%), failure in 19 (38%), and death in 6 (12%). Patients with LN with TMA had higher rates of treatment failure (P = 0.02) compared to the group without TMA.

DISCUSSION

The presence of TMA in patients with LN is associated with adverse clinicopathological presentation and poor outcome.

Aplastic anemia and risk of deep vein thrombosis and pulmonary embolism: A nationwide cohort study

OBJECTIVES

Deep vein thrombosis (DVT) and pulmonary embolism (PE) constitute venous thromboembolism (VTE), which is not fully known in aplastic anemia (AA). Therefore, we investigated the incidence and risk of VTE in AA patients.

METHODS

We conducted a nationwide cohort study to investigate the risk of DVT and PE in patients with AA. We identified patients with newly diagnosed AA as the AA cohort between 2000 and 2010 from the National Health Insurance Research Database (NHIRD). The initial admission date for AA diagnosis was set as the index date. For each patient with AA, 4 patients without a history of AA, frequency matched by sex, age (every 5-y span), and year of index date, were the non-AA cohort. All patients were followed from the index date to the date of DVT or PE diagnosis, withdrawal from the NHIRD, or the end of 2011. Cox models were used to evaluate the risk of developing DVT and PE in the AA cohort.

RESULTS

We included 4001 and 15,998 patients in the AA and non-AA cohorts, respectively, and the overall incidence densities of VTE were significantly higher in the AA cohort than in the non-AA cohort (42.3 vs 10.2 per 10,000person-years). The AA cohort had a 2.56-fold higher risk of VTE (95% confidence interval [CI]=1.81-3.63) than did the non-AA cohort.

CONCLUSION

This nationwide cohort study indicated that AA is associated with increased incidence and risk of VTE.

Characterization of Patients With Lupus Nephritis Included in a Large Cohort From the Spanish Society of Rheumatology Registry of Patients With Systemic Lupus Erythematosus (RELESSER)

The aim of the study was to profile those patients included in the RELESSER registry with histologically proven renal involvement in order to better understand the current state of lupus nephritis (LN) in Spain. RELESSER-TRANS is a multicenter cross-sectional registry with an analytical component. Information was collected from the medical records of patients with systemic lupus erythematosus who were followed at participating rheumatology units. A total of 359 variables including demographic data, clinical manifestations, disease activity, severity, comorbidities, LN outcome, treatments, and mortality were recorded. Only patients with a histological confirmation of LN were included. We performed a descriptive analysis, chi-square or Student's t tests according to the type of variable and its relationship with LN. Odds ratio and confidence intervals were calculated by using simple logistic regression. LN was histologically confirmed in 1092/3575 patients (30.5%). Most patients were female (85.7%), Caucasian (90.2%), and the mean age at LN diagnosis was 28.4 ± 12.7 years. The risk for LN development was higher in men (M/F:47.85/30.91%, P < 0.001), in younger individuals (P < 0.001), and in Hispanics (P = 0.03). Complete response to treatment was achieved in 68.3% of patients; 10.35% developed ESRD, which required a kidney transplant in 45% of such cases. The older the patient, the greater was the likelihood of complete response (P < 0.001). Recurrences were associated with persistent lupus activity at the time of the last visit (P < 0.001) and with ESRD (P < 0.001). Thrombotic microangiopathy was a risk factor for ESRD (P = 0.04), as for the necessity of dialysis (P = 0.01) or renal transplantation (P = 0.03). LN itself was a poor prognostic risk factor of mortality (OR 2.4 [1.81-3.22], P < 0.001). Patients receiving antimalarials had a significantly lower risk of developing LN (P < 0.001) and ESRD (P < 0.001), and responded better to specific treatments for LN (P = 0.014). More than two-thirds of the patients with LN from a wide European cohort achieved a complete response to treatment. The presence of positive anti-Sm antibodies was associated with a higher frequency of LN and a decreased rate of complete response to treatment. The use of antimalarials reduced both the risk of developing renal disease and its severity, and contributed to attaining a complete renal response.

Lupus-associated thrombotic thrombocytopenic purpura-like microangiopathy

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.

Two Types of Renovascular Lesions in Lupus Nephritis with Clinical Thrombotic Thrombocytopenic Purpura

Renovascular lesions of lupus nephritis (LN) were classified into five categories by D'Agati in Heptinstall's Pathology of the Kidney, with thrombotic microangiopathy (TMA) and clinical thrombotic thrombocytopenic purpura (TTP) being combined. We encountered 2 cases with histological LN (class III and lass V), and they presented with clinical features of TTP, such as acute renal failure, microangiopathic hemolytic anemia, thrombocytopenia, fever, and central neurologic symptoms. Immunosuppressive therapy with plasmapheresis was performed in both patients. Case 1 progressed to end-stage renal failure requiring dialysis and died, while case 2 responded to treatment. In case 1, small renal arteries showed positive mural staining for IgG and C3, while intraluminal material was negative for IgG and C3 [although it was positive for phosphotungstic acid-hematoxylin (PTAH), indicating fibrin deposition]. In case 2, small renal arteries showed mural staining for IgG, C1q, and C3, with the intraluminal material also being positive for these immunoglobulins, but negative for PTAH. These cases suggest that immunosuppressive therapy with plasmapheresis can control LN when intravascular thrombosis is related to immune complexes associated with activation of the early complement components C1q and C3. In contrast, immunosuppressive therapy with plasmapheresis may not be effective when intravascular thrombosis is unrelated to these factors and involves fibrin deposition. Accordingly, in LN patients with clinical features of TTP, we report two types of renovascular lesions, in addition to typical vascular change of TMA with no immune deposits seen in nonlupus patients.

Risk Factors for Autoimmune Diseases Development After Thrombotic Thrombocytopenic Purpura

Autoimmune thrombotic thrombocytopenic purpura (TTP) can be associated with other autoimmune disorders, but their prevalence following autoimmune TTP remains unknown. To assess the prevalence of autoimmune disorders associated with TTP and to determine risk factors for and the time course of the development of an autoimmune disorder after a TTP episode, we performed a cross sectional study. Two-hundred sixty-one cases of autoimmune TTP were included in the French Reference Center registry between October, 2000 and May, 2009. Clinical and laboratory data available at time of TTP diagnosis were recovered. Each center was contacted to collect the more recent data and diagnosis criteria for autoimmunity. Fifty-six patients presented an autoimmune disorder in association with TTP, 9 years before TTP (median; min: 2 yr, max: 32 yr) (26 cases), at the time of TTP diagnosis (17 cases) or during follow-up (17 cases), up to 12 years after TTP diagnosis (mean, 22 mo). The most frequent autoimmune disorder reported was systemic lupus erythematosus (SLE) (26 cases) and Sjögren syndrome (8 cases). The presence of additional autoimmune disorders had no impact on outcomes of an acute TTP or the occurrence of relapse. Two factors evaluated at TTP diagnosis were significantly associated with the development of an autoimmune disorder during follow-up: the presence of antidouble stranded (ds)DNA antibodies (hazard ratio (HR): 4.98; 95% confidence interval (CI) [1.64-15.14]) and anti-SSA antibodies (HR: 9.98; 95% CI [3.59-27.76]). A follow-up across many years is necessary after an acute TTP, especially when anti-SSA or anti-dsDNA antibodies are present on TTP diagnosis, to detect autoimmune disorders early before immunologic events spread to prevent disabling complications.

Pure lupus podocytopathy first presenting as thrombotic thrombocytopenic purpura-like syndrome

Lupus podocytopathy (LP) is an uncommon proteinuric disorder in the spectrum of lupus nephropathy. Its histological features are similar to those described in minimal change disease (MCD) with or without mesangial immune deposits. Although infrequent, a close relationship between systemic lupus erythematosus (SLE) and thrombotic thrombocytopenic purpura (TTP) is well accepted. Proteinuria in the setting of SLE has previously been associated with the development of TTP-like syndrome. As far as we know, LP first presenting as a TTP-like syndrome has never been reported. Here, we describe the case of a previously healthy 45-year-old woman who developed simultaneously these two conditions and then we briefly review the literature on the topic, emphasizing the previous cases of concurrent initial diagnosis of both SLE and MCD (n = 7) and SLE and TTP (n = 72). In conclusion, renal biopsy is central to the management of SLE patients with nephrotic syndrome. Furthermore, in a SLE patient with anemia and thrombocytopenia, TTP should be part of the differential diagnosis, even when no schistocytes were detected in peripheral blood smear.

Atypical Hemolytic Uremic Syndrome and Chronic Ulcerative Colitis Treated with Eculizumab

Background

Hemolytic-uremic syndrome (HUS) presents with hemolytic anemia, thrombocytopenia, and thrombotic microangiopathy of the kidney and usually results from Shiga-toxin induced activation of the alternative complement pathway. Gastroenteritis is a common feature of the Shiga-toxin producing Escherichia coli HUS, referred to as STEC-HUS. An inherited or acquired complement dysregulation may lead to HUS referred to as non-STEC or atypical (a)HUS. Although gastroenteritis is not a common presentation of aHUS, some patients develop ischemic colitis and may be misdiagnosed as acute appendicitis or acute ulcerative colitis (UC).

Case Diagnosis –Treatment

We present a patient with low circulating complement (C) 3 levels who developed aHUS in the course of chronic active UC. Resolution of renal and gastrointestinal manifestations in response to treatment with eculizumab, a humanized monoclonal antibody against terminal C5 protein suggests the role of alternative complement in the pathogenesis of both, aHUS and UC.

Conclusion

This case illustrates that dysregulation of the alternative complement pathway may manifest in other organs besides the kidney and that the circulating C3 levels do not correlate with the disease activity or the clinical response to eculizumab.

Thrombotic thrombocytopenic purpura as an initial presentation of systemic lupus erythematosus with acquired ADAMTS 13 antibody

We report a female patient presenting with headache, fatigue, ecchymoses and recent, excessive vaginal bleeding. Prompt review of the peripheral blood smear showed evidence of microangiopathic haemolytic anaemia (MAHA) and thrombocytopenia. Thrombotic thrombocytopenic purpura (TTP) was suspected. Plasma exchange and corticosteroids were started urgently. The patient responded favourably to the treatment. Subsequently, positive serological markers returned and were compatible with systemic lupus erythematosus (SLE). A disintegrin and metalloproteinase with thrombospondin type 1 motifs, member 13 (ADAMTS 13) activity was remarkably low with a positive inhibitory ADAMTS 13 antibody. Mycophenolate and hydroxychloroquine were started along with a prolonged course and taper of corticosteroids. These medications have been maintained with an excellent response in 14 months of follow-up.

Complement the hemostatic system: an intimate relationship

The complement system is important part of our innate immune system and interacts directly with the hemostatic system. Disorders of complement activation or dysregulation resulting in excess complement generation, such as Paroxysmal Nocturnal Hemoglobinuria (PNH), atypical Hemolytic uremic Syndrome (aHUS) and antiphospholipid syndrome (APLS) have been associated with significant thrombophilia. Terminal Complement (C5b-9) deposition on endothelial and tumor cell membranes has also been reported in a variety of cancer. Recent developments in complement inhibition have given us new insights into the mechanism of thrombosis in these disorders.

Risk factors and clinical profile of thrombotic thrombocytopenic purpura in systemic lupus erythematosus patients. Is this a distinctive clinical entity in the thrombotic microangiopathy spectrum?: a case control study

INTRODUCTION

The association of thrombotic thrombocytopenic purpura (TTP) with systemic lupus erythematosus (SLE) is rare. It is associated with high morbidity and mortality. Information about risk factors and clinical outcomes is scant.

MATERIAL AND METHODS

A retrospective case-control study was performed in a referral center in Mexico City between 1994 and 2013. Patients were diagnosed with TTP if they fulfilled the following criteria: microangiopathic haemolytic anaemia, thrombocytopenia, high LDH levels, normal fibrinogen and negative Coombs' test. Patients with SLE were diagnosed with ≥ 4 ACR criteria. We included three study groups: group A included patients with SLE-associated TTP (TTP/SLE; cases n = 22, TTP events n = 24); patients with non-autoimmune TTP (NA-TTP; cases n = 19, TTP events n = 22) were included in group B and patients with SLE without TTP (n = 48) in group C.

RESULTS

After multivariate analysis, lymphopenia < 1000/mm3 [OR 19.84, p = 0.037], high SLEDAI score three months prior to hospitalisation [OR 1.54, p = 0.028], Hg <7g/dL [OR 6.81, p = 0.026], low levels of indirect bilirubin [OR 0.51, p = 0.007], and less severe thrombocytopenia [OR 0.98, p = 0.009] were associated with TTP in SLE patients. Patients with TTP/SLE received increased cumulative steroid dose vs. NA-TTP (p = 0.006) and a higher number of immunosuppressive drugs (p = 0.015). Patients with TTP/SLE had higher survival than NA-TTP (p=0.033); however, patients hospitalised for TTP/SLE had a higher risk of death than lupus patients hospitalised for other causes

CONCLUSIONS

Lymphopenia is an independent risk factor for TTP/SLE. It is likely that patients with TTP/SLE present with less evident clinical features, so the level of suspicion must be higher to avoid delay in treatment.

CD(+)(4)CD(+)(25) Treg cells in thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus patients

AIM

CD(+)(4)CD(+)(25) Treg cells are of critical importance for maintenance of tolerance. The purpose of the this study was to observe the number of CD(+)(4)CD(+)(25) Treg cells in the patients with thrombotic thrombocytopenic purpura (TTP) associated with systemic lupus erythematosus (SLE), and to study pathogenesis of TTP with SLE.

METHODS

Seven patients with TTP associated with SLE and seven healthy volunteers were studied. The CD(+)(4)CD(+)(25) Treg cells were examined by flow cytometry. Clinical and laboratory data, such as urinary protein, serum creatinine, endothelial markers and immunologic serologics, were obtained from each patient and healthy volunteer. Glomerular injury was assessed by histopathology. Serum IL-2, IL-4, IL-6 and anti-endothelial cell antibody were analyzed by ELISA and anti-ADAMTS13 antibody were detected by Western blotting.

RESULTS

CD(+)(4)CD(+)(25) Treg cells significantly decreased in TTP with SLE patients compared with controls (p < 0.05). CD(+)(4)CD(+)(25) Treg cells are negatively correlated with blood urea nitrogen, serum uric acid, supernatant IL-4, and proteinuria, and positively with estimated glomerular filtration rate (eGFR) in TTP with SLE patients. [Formula: see text] Treg cells gradually decreased as the severity of renal histology increased. Serum IL-2, IL-6, supernatant IL-4, anti-endothelial cell antibody, and anti-ADAMTS13 antibody significantly increased in TTP with SLE patients compared to those of the control groups (all p < 0.05). In contrast, serum levels of C3 were significantly decreased in TTP with SLE patients compared to those of the control groups (p < 0.05).

CONCLUSIONS

CD(+)(4)CD(+)(25) Treg cells are not only lower in TTP with SLE patients, but also are correlated with disease severity in TTP with SLE patients.CD(+)(4)CD(+)(25)Treg cells may play an important role in the pathogenesis of TTP with SLE.

ADAMTS-13 metalloprotease abnormalities in systemic lupus erythematosus: is there a correlation with disease status?

To clarify the role of ADAMTS-13 in the pathogenesis of thrombotic microangiopathy in systemic lupus erythematosus (SLE) we evaluated ADAMTS-13 profile (metalloprotease antigen levels, anti-ADAMTS-13 autoantibody levels, activity) in distinct patient groups according to disease activity, extent of cumulative tissue damage and history of antiphospholipid syndrome or end-organ damage. Forty-one lupus patients were analysed. ADAMTS-13 metalloprotease antigen levels and anti-ADAMTS-13 autoantibodies were evaluated by ELISA. ADAMTS-13 activity was measured by Fluorescence resonance energy transfer (FRET) technique. ADAMTS-13 metalloprotease antigen levels were significantly decreased in patients with Systemic Lupus International Collaborative Clinics/American College of Rheumatology (SLICC/ACR) >1 (p<0.05). ADAMTS-13 metalloprotease antigen levels also exhibited a significant inverse correlation with anti-dsDNA levels (r= -0.60, p<0.05). Anti-ADAMTS-13 autoantibodies were marginally higher in patients with positive anti-dsDNA (p=0.08). Additionally, patients with positive anti-ADAMTS-13 autoantibodies exhibited the lowest activity levels (p<0.05). To our knowledge ADAMTS-13 profile in SLE has not been studied in regard to composite structured indices. The results of this study suggest that in patients with active SLE or considerable cumulative tissue damage, ADAMTS-13 levels may be decreased and anti-ADAMTS-13 autoantibodies may partially mediate this reduction. Further evaluation of ADAMTS-13 profile may explain its role in the pathogenesis of thrombotic microangiopathy in lupus patients and reveal a potential prognostic marker of microthrombotic manifestations in SLE.

Clinical features and prognostic factors of thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus: a literature review of 105 cases from 1999 to 2011

This study aims to review clinical features, treatments, and prognostic factors of thrombotic thrombocytopenic purpura (TTP) associated with systemic lupus erythematosus patients (sTTP). The case reports of sTTP published in world literature from 1999 to 2011 were collected, and 105 cases were divided into death group and survival group. The epidemiologic characteristics, clinical manifestations, laboratory examinations, treatments, and prognostic factors were analyzed. We found that coexistence of renal and neurological impairments were significantly frequent in the death group (100 %) than in the survival group (56.5 %) (P = 0.002). Type IV was predominant in 57.7 % of renal pathological damage, followed by type V (11.5 %), type II (5.8 %), and thrombotic microangiopathy (TMA) (5.8 %). TMA appeared more frequently (50 %) in the death group than in the survival group (6.25 %) (P = 0.042). End-stage renal disease occurred in nine cases with type IV in five (55.6 %), type TMA in one (11.1 %), and unspecified in three cases (33.3 %). Of 32 cases, 40.6 % showed severe ADAMTS13 deficiency and returned to normal or mildly deficient after remission. The total mortality rate of sTTP was 12.4 % and the mortality rate of patients with infection (27.3 %) was significantly higher than those without infection (8.4 %) (P = 0.028). Plasma exchange and glucocorticoids were administrated in over 80 % of cases with 65.7 % remission rate, while additional cytotoxics or rituximab was mostly used in refractory sTTP and achieved over 90 % of remission rate. Above all, coexistence of renal and neurological impairments, infection, and renal damage with type IV or TMA might denote a poor prognosis of sTTP.

Recessive mutations in DGKE cause atypical hemolytic-uremic syndrome

Pathologic thrombosis is a major cause of mortality. Hemolytic-uremic syndrome (HUS) features episodes of small-vessel thrombosis resulting in microangiopathic hemolytic anemia, thrombocytopenia and renal failure. Atypical HUS (aHUS) can result from genetic or autoimmune factors that lead to pathologic complement cascade activation. Using exome sequencing, we identified recessive mutations in DGKE (encoding diacylglycerol kinase ɛ) that co-segregated with aHUS in nine unrelated kindreds, defining a distinctive Mendelian disease. Affected individuals present with aHUS before age 1 year, have persistent hypertension, hematuria and proteinuria (sometimes in the nephrotic range), and develop chronic kidney disease with age. DGKE is found in endothelium, platelets and podocytes. Arachidonic acid-containing diacylglycerols (DAG) activate protein kinase C (PKC), which promotes thrombosis, and DGKE normally inactivates DAG signaling. We infer that loss of DGKE function results in a prothrombotic state. These findings identify a new mechanism of pathologic thrombosis and kidney failure and have immediate implications for treating individuals with aHUS.

The spectrum of renal thrombotic microangiopathy in lupus nephritis

INTRODUCTION

Among various lupus renal vascular changes, thrombotic microangiopathy (TMA) presented with the most severe clinical manifestations and high mortality. The pathogenesis of TMA in systemic lupus erythematosus (SLE) was complicated. The aim of this study was to assess clinical manifestations, laboratory characteristics, pathological features and risk factors for clinical outcomes of lupus nephritis patients co-existing with renal TMA in a large cohort in China.

METHODS

Clinical and renal histopathological data of 148 patients with biopsy-proven lupus nephritis were retrospectively analyzed. Serum complement factor H, A Disintegrin and Metalloprotease with Thrombospondin type I repeats 13 (ADAMTS-13) activity, antiphospholipid antibodies and C4d deposition on renal vessels were further detected and analyzed.

RESULTS

In the 148 patients with lupus nephritis, 36 patients were diagnosed as co-existing with renal TMA based on pathological diagnosis. Among the 36 TMA patients, their clinical diagnoses of renal TMA were as followings: 2 patients combining with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome, 2 patients combining with anti-phospholipid syndrome, 2 patients with malignant hypertension, 1 patient with scleroderma and the other 29 patients presenting with isolated renal TMA. Compared with the non-renal TMA group, patients with renal TMA had significantly higher urine protein (7.09±4.64 vs. 4.75±3.13 g/24h, P=0.007) and serum creatinine (159, 86 to 215 vs. 81, 68 to 112 μmol/l, P<0.001), higher scores of total activity indices (AI) (P<0.001), endocapillary hypercellularity (P<0.001), subendothelial hyaline deposits (P=0.003), interstitial inflammation (P=0.005), glomerular leukocyte infiltration (P=0.006), total chronicity indices (CI) (P=0.033), tubular atrophy (P=0.004) and interstitial fibrosis (P=0.018). Patients with renal TMA presented with poorer renal outcome (P=0.005) compared with the non-TMA group. Renal TMA (hazard ratio (HR): 2.772, 95% confidence interval: 1.009 to 7.617, P=0.048) was an independent risk factor for renal outcome in patients with lupus nephritis. The renal outcome was poorer for those with both C4d deposition and decreased serum complement factor H in the TMA group (P=0.007).

CONCLUSIONS

There were various causes of renal TMA in lupus nephritis. Complement over-activation via both classical and alternative pathways might play an important role in the pathogenesis of renal TMA in lupus nephritis.

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.