A toggle switch linking coagulation and innate immunity in antiphospholipid antibody syndrome

Thrombotic Diathesis Combined With Connective Tissue Disease in a Chinese Teenage Male: A Case Report

Thrombophilia is a pathological condition characterized by an increased propensity for blood clot formation and thromboembolism, resulting from various genetic or acquired factors. It can be classified as hereditary or acquired based on its etiology. Autoimmune diseases are common contributors to acquired thrombophilia. This article presents the clinical diagnosis and treatment of a patient with hereditary thrombophilia complicated by connective tissue disease, aiming to provide a reference for the clinical management of thrombophilia. A case of a 13-year-old male presenting with persistent pain and swelling in the left lower limb was investigated. Physical examination revealed there was swelling in the left lower limb with slightly elevated skin tension and warmth. Lower Limb Ultrasound: Thrombosis in the left calf muscle venous system. D-dimer was elevated and antinuclear antibodies (ANA) and titers were Positive. Family history revealed several kinsfolk had thromboembolic diseases. The patient underwent hydroxychloroquine sulfate, warfarin sodium, and aspirin for maintenance therapy. 10 months later, the patient presented with deep vein thrombosis in the left sole again. Thrombosis is a multifactorial process, and patients may have multiple thrombophilic risk factors simultaneously. Etiological screening for thrombophilia should not focus solely on a single risk factor. If autoimmune diseases cannot fully explain the severity of thrombophilia, other risk factors should be further investigated. It is essential to appropriately determine the indications for genetic screening in patients with VTE and autoimmune diseases.

A Lipidomic Study to Identify the Serum Lipid Markers for Obstetric Antiphospholipid Syndrome

This study used untargeted lipidomics to analyze the characteristics of lipid metabolism in the serum of women with antiphospholipid syndrome. Twenty female patients with APS and 20 healthy controls were recruited to this study. Untargeted lipidomics with liquid chromatography-tandem mass spectrometry was used to profile serum lipids. Correlation analyses were performed on the significant differential lipids. Least absolute shrinkage and selection operator (LASSO) regression and binary logistic regression analyses were performed to find possible biomarkers. Finally, receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of biomarkers. The serum lipid profile of women with APS was significantly different from that of healthy controls. After statistical analysis and database matching, 12 lipids were found to be significantly different between the two groups, with the most obvious differences being triacylglycerols and phosphatidylcholines. LASSO regression and binary logistic regression models revealed that PC (17:0/22:6) and ACar (17:3) may be serum biomarkers of APS. ROC curve analysis shows that PC (17:0/22:6) and ACar (17:3) combined gave an area under the curve of 0.865 for the diagnosis of APS. PC (17:0/22:6) and ACar (17:3) could be used as biomarkers of APS.

Antiphospholipid Syndrome and Kidney Involvement

BACKGROUND

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by the development of autoantibodies and the impairment of the coagulation system. Knowledge about this syndrome is increasing over time, but kidney involvement, especially APS nephropathy, still represents a challenge for physicians.

SUMMARY

A "two hit" model has been hypothesized to explain APS pathophysiology, and the role played by some factors, such as the complement system, is becoming more and more clear. From a clinical point of view, along with thrombosis in any site and/or obstetric morbidities, that are the hallmarks of APS, a constellation of several other clinical symptoms is related to APS. These symptoms alone are not sufficient to fulfill Sydney criteria for APS and this could potentially lead to omitting some diagnoses. The mainstay of management of APS is antithrombotic therapy, but there are expectations for new drugs that regulate the immune system. APS could affect the kidneys in many ways and among them, APS nephropathy is an intriguing entity that has been overlooked in recent years. Novel studies on APS nephropathy are lacking.

KEY MESSAGES

In this review, we discuss what we currently know about APS and its relationship with the kidney, with an eye toward the future perspectives. Multicenter studies on APS nephropathy are necessary in order to develop targeted therapies.

Clinical-Pathological Characteristics of Renal Injuries Identify Different Clusters in Patients With Antiphospholipid Antibodies

Introduction

Significant heterogeneity still exists in the nomenclature of renal involvement in antiphospholipid syndrome (APS).

Methods

We applied a hierarchical cluster analysis to determine subgroups of patients according to clinical, laboratory, and renal histology characteristics in a cohort of subjects with confirmed antiphospholipid antibodies (aPL) positivity and biopsy proven aPL-related renal injuries. Kidney outcomes were then assessed at 12 months.

Results

A total of 123 aPL-positive patients were included in the study (101 [82%] female, 109 [88.6%] with systemic lupus erythematosus [SLE], 14 (11.4%) with primary APS [PAPS]). Three clusters were identified. Twenty-three patients (18.7%) were included in the first cluster (cluster 1), characterized by a higher prevalence of glomerular capillary and arteriolar thrombi and fragmented red blood cells in the subendothelial space. Cluster 2 included 33 patients (26.8%) and showed a higher prevalence of fibromyointimal proliferative lesions as seen in hyperplastic vasculopathy. Cluster 3 was the largest (67 patients, mainly with SLE) and was characterized by higher prevalence of subendothelial edema, of both glomerular capillaries and arterioles.

Conclusion

Three different clusters of patients with aPL and renal injuries emerged from our study as follows: the first, with the worst renal prognosis, was associated with features of thrombotic microangiopathy (TMA), thrombosis, triple aPL positivity and higher adjusted Global APS Score (aGAPSS) values; the second, characterized by hyperplastic vasculopathy with an intermediate prognosis, was seen more frequently in patients with cerebrovascular manifestations; and the third, more benign in terms of outcomes and with no overt association with thrombotic features, was characterized by endothelial swelling in concomitant lupus nephritis (LN).

Refractory Systemic Lupus Erythematosus: Identification and Pharmacological Management

Systemic lupus erythematosus (SLE) is characterized by an aberrant immune response, leading to an extremely heterogeneous clinical presentation, potentially affecting different systems and organs. Despite the fact that SLE mortality has greatly decreased since the introduction of steroids, some forms of refractory/severe SLE still have the potential to result in permanent organ damage as well as increased mortality and morbidity. Furthermore, SLE patients with multiple comorbidities may face a clinical conundrum and have a bad prognosis. An improved prognosis for severe refractory SLE depends on prompt and appropriate treatment. Due to the scarcity of solid data from a well-characterized group of patients with refractory/severe SLE coming from randomized controlled studies, this review aims to shed light on this with real-world evidence from clinical research performed at our Unit, the University Center of Excellence on Nephrologic, Rheumatologic and Rare Diseases with Nephrology and Dialysis Unit and Center of Immuno-Rheumatology and Rare Diseases (CMID) (Turin, Italy). In order to determine the key clinical and prognostic features, and therapeutic approaches for severe and/or refractory SLE, our experience will be described together with existing literature, primarily focused on dermatological, neuropsychiatric, and renal symptoms.

A new pro-thrombotic mechanism of neutrophil extracellular traps in antiphospholipid syndrome: impact on activated protein C resistance

OBJECTIVES

In antiphospholipid syndrome (APS), precise evaluation of thrombotic risk is a major challenge. Different players, such as activated protein C (APC) resistance or neutrophil extracellular traps (NETs), contribute to the risk of thrombosis. Nevertheless, no study has investigated the interaction between these actors. The main objective of this study was to investigate the relation between NETs and APC resistance.

METHODS

We designed a cross-sectional study including APS/antiphospholipid antibodies (aPL) patients and patients with autoimmune diseases (AID). We performed thrombin generation tests without and with APC to determine APC resistance. To evaluate circulating NETs, we measured plasma levels of myeloperoxidase-DNA complexes and cell-free DNA with ELISA.

RESULTS

We recruited 117 patients with definite APS/aPL or AID. We found a positive correlation between NETs and APC resistance, in APS patients and specifically in patients with high thrombotic risk, displaying lupus anticoagulant (LA) or positivity of all 3 aPL tests (triple+), or anti-domain I IgG (aDI+). All these patient subgroups had increased NETs concentrations and APC resistance. As the risk profile for thrombosis increased, the relationship between NETs and APC resistance was stronger.

CONCLUSION

We have shown that NETs participate in the hypercoagulable state of APS patients by contributing to APC resistance, in particular in high-risk patients. In these most at-risk patients, a targeted action on NETs could reduce APC resistance and constitute a new therapeutic approach in the treatment of APS patients in addition to antithrombotic therapy.