Systemic lupus erythematosus-complicating immune thrombocytopenia: From pathogenesis to treatment

Relationship of Hematological Profiles with the Serum Complement System in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder identified by hematological abnormalities including anemia, leukopenia, and thrombocytopenia. Complement system disturbance is implicated in the pathogenesis of SLE. In this work, we aim to study how a full assessment of the complement system, which includes the evaluation of its three pathways, relates to blood cell counts in a population of patients with SLE. New-generation functional assays of the classical, alternative, and lectin pathways of the complement system were conducted in 284 patients with SLE. Additionally, serum levels of inactive molecules (C1q, C2, C3, C4, factor D) and activated molecules (C3a), as well as regulators (C1-inhibitor and factor H), were evaluated. Complete blood cell counts were analyzed. Multivariable linear regression analysis was performed to study the relationship of hematological profiles with this full characterization of the complement system. After multivariable adjustments that included age, sex, SLICC-DI (damage), and SLEDAI (activity) scores, as well as the use of aspirin, prednisone, methotrexate, azathioprine, and mycophenolate mofetil, several relationships were observed between the C pathways and the individual products and blood cells profile. Lower values of C1q and C2 were associated with lower hemoglobin levels. Lower leukocyte counts showed significantly lower values of C4, C1 inhibitor, C3, factor D, and alternative pathway functional levels. Neutrophil counts showed significant negative relationships only with the alternative pathway and C1-inh. In the case of lymphocytes, associations were found, especially with functional tests of the classical and alternative pathways, as well as with C2, C4, C3, and C3a. On the contrary, for platelets, significance was only observed, after multivariable adjustment, with lower C2 concentrations. In conclusion, the serum complement system and hematological profile in SLE are independently linked, after adjustment for disease activity and damage. These relationships are basically negative and are predominantly found in lymphocytes.

Effectiveness and safety of eltrombopag in connective tissue disease patients with refractory immune thrombocytopenia: a retrospective study

Objectives

We aimed to investigate the safety and effectiveness of eltrombopag for adult patients with refractory immune thrombocytopenia (ITP) secondary to connective tissue disease (CTD).

Methods

This is a single-centre, retrospective cohort and propensity score-matched study. Data from CTD-ITP patients treated with eltrombopag between January 2019 and January 2023 were retrospectively analysed. Baseline characteristics and follow-up information were recorded. CTD patients without ITP were matched to identify the risk factors associated with CTD-ITP performed by Logistic regression analysis.

Results

Twenty patients were enrolled, including 5 systemic lupus erythematosus (SLE), 9 Sjögren's syndrome (SS) and 6 undifferentiated connective tissue disease (UCTD). Nineteen (95%) patients were female, and the median age was 59 years. Logistic regression analysis showed that anaemia (OR = 8.832, P = 0.007) was associated with increased risk of ITP, while non-erosive arthritis (OR = 0.045, P = 0.001) and interstitial lung disease (OR = 0.075, P = 0.031) were associated with reduced risk. Fourteen patients (70%) achieved a complete response (CR) and one (5%) achieved a partial response (PR). The median response time was 14 days. The median platelet count was 8.5 × 109/l at baseline of eltrombopag and increased to 122 × 109/l after 4 weeks. No adverse events were observed.

Conclusions

Eltrombopag appears to be effective, safe and well-tolerated in refractory ITP patients with CTD; larger studies are needed to confirm the generalizability of these findings.

Prediction of Treatment Effect of SLE-ITP Patients Based on Cost-Sensitive Neural Network and Variational Autoencoder

OBJECTIVE

The aim of the study was to examine the factors influencing the therapeutic effect of patients with systemic lupus erythematosus combined with immune thrombocytopenia (SLE-ITP) and develop a prediction model to predict the therapeutic effect of SLE-ITP.

METHODS

Three hundred twenty-four SLE-ITP patients were retrieved from the electronic health record database of SLE patients in Jiangsu Province according to the latest treatment response criteria for ITP. We adopted the Cox model based on the least absolute shrinkage and selection operator to explore the impact factors affecting patient therapeutic effect, and we developed neural network model to predict therapeutic effect, and in prediction model, cost-sensitivity was introduced to address data category imbalance, and variational autoencoder was used to achieve data augmentation. The performance of each model was evaluated by accuracy and the area under the receiver operator curve.

RESULTS

The results showed that B-lymphocyte count, H-cholesterol level, complement-3 level, anticardiolipin antibody, and so on could be used as predictors of SLE-ITP curative effect, and abnormal levels of alanine transaminase, immunoglobulin A, and apolipoprotein B predicted adverse treatment response. The neural network treatment effect prediction model based on cost-sensitivity and variational autoencoder was better than the traditional classifiers, with an overall accuracy rate closed to 0.9 and a specificity of more than 0.9, which was useful for clinical practice to identify patients at risk of ineffective treatment response and to achieve better individualized management.

CONCLUSIONS

By predicting the curative effect of SLE-ITP, the severity of patients can be determined, and then the best treatment strategy can be planned to avoid ineffective treatment.

Classifying systemic lupus erythematosus using laboratory items alone: a preliminary study

OBJECTIVES

To explore the performance of laboratory items alone in systemic lupus erythematosus (SLE) classification.

METHODS

Our cohort consisted of 352 and 385 (control) patients with and without SLE. This study evaluated the performance of the American College of Rheumatology (ACR)-1997, Systemic Lupus International Collaborating Clinics (SLICC)-2012, European League Against Rheumatism (EULAR)/ACR-2019, and Systemic Lupus Erythematosus Risk Probability Index (SLERPI) using laboratory items alone, including blood and urine test results.

RESULTS

The median ratio of laboratory items/total items was 66.7%, 75.0%, 60.4%, and 77.4% in ACR-1997, SLICC-2012, EULAR/ACR-2019, and SLERPI, respectively. After including laboratory items alone, the sensitivity of ACR-1997, SLICC-2012, EULAR/ACR-2019, and SLERPI was 31.3% (95% confidence interval [CI]: 26.4%-36.4%), 79.8% (95% CI: 75.3%-83.9%), 75.9% (95% CI: 71.0%-80.2%), and 85.2% (95% CI: 81.1%-88.8%), respectively. We referenced the SLERPI and removed the additional restrictions, i.e., SLICC-2012 criteria only needs to fulfill at least four items (mSLICC-2012) and EULAR/ACR-2019 criteria needs to have ≥ 10 points (mEULAR/ACR-2019) to qualify for SLE classification. The mSLICC-2012 and mEULAR/ACR-2019 criteria, including laboratory items alone, newly identified 13 and 25 patients, respectively. Based on laboratory items alone, the combination of mSLICC-2012, mEULAR/ACR-2019, and SLERPI identified 348 patients with an improved sensitivity of 90.6% (95% CI: 87.1%-93.5%). Patients, who were classified according to the mEULAR/ACR-2019 criteria, all met the other criteria.

CONCLUSION

Incorporating laboratory items alone was clinically feasible to help identify SLE. SLERPI and SLICC-2012, using laboratory items alone, were more worthwhile to promote in the clinic compared with EULAR/ACR-2019. Key Points • Laboratory items play a crucial role in the SLE classification criteria, and incorporating laboratory items alone was clinically feasible to help in the identification of SLE. • The SLERPI and SLICC-2012, using laboratory items alone, were more worthwhile to promote in the clinic compared with EULAR/ACR-2019, and the combination of the two could further improve the sensitivity. • The relative simplicity of evaluating laboratory indices may help nonrheumatologists and inexperienced rheumatologists to identify SLE more quickly, thereby reducing the risk of delayed diagnosis in patients.

Calcineurin inhibitors in the treatment of systemic lupus erythematosus during pregnancy: A narrative review with emphasis on efficacy and safety

Systemic lupus erythematosus (SLE) predominantly affects child-bearing women, leading to an elevated risk of maternal and fetal complications and adverse pregnancy outcomes. Since some medications can cross the placental barrier that persist a threat to both mother and fetus, the risk-benefit ratio of SLE medications should be taken into consideration during pregnancy. Calcineurin inhibitor (CNI), mainly including cyclosporin A, tacrolimus, and voclosporin, is a category of immunosuppressive agents that inhibit calcium/calmodulin-dependent phosphatase calcineurin to block T cell activation. Based on the current clinical evidence, CNI is an alternative in pregnant SLE patients with persistent disease activity (especially lupus nephritis patients) and non-responders to azathioprine. However, there is no comprehensive review that summarizes the efficacy and safety profile of CNI for SLE management during pregnancy. This review presents a summary on the utilization of CNI for SLE management during pregnancy, including the mechanism of action, gestational amelioration of lupus flare, and the balance of maternal benefit-fetal risk, which may provide more references for the management of SLE pregnancies.

Rituximab alleviates pediatric systemic lupus erythematosus associated refractory immune thrombocytopenia: a case-based review

A complication of pediatric systemic lupus erythematosus (pSLE) is immune thrombocytopenia (ITP). Although corticosteroids and immunoglobulins are frequently used as preliminary treatments, some patients do not respond to them. Rituximab has been reported to be safe and effective in the treatment of pSLE complicated with refractory ITP. Research is currently underway to determine the optimal rituximab dose for these individuals. We report a case of a child with SLE-associated ITP (SLE-ITP) who was successfully treated with rituximab. Rituximab is likely the most viable therapeutic option for refractory SLE-ITP. Furthermore, a comprehensive review of the relevant literature was performed and a concise overview of the pathogenesis and available treatment modalities for pediatric patients diagnosed with SLE and concurrent ITP was provided.

Platelets are a major player and represent a therapeutic opportunity in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by immune dysregulation and organ injury with a premature mortality due to cardiovascular diseases. Platelets, that are primarily known for their role in hemostasis, have been shown to play an active role in the pathogenesis and in the progression of immune-mediated inflammatory diseases. Here we summarize the evidence of their roles in SLE pathogenesis which supports the development of targeted treatments. Platelets and their precursors, the megakaryocytes, are intrinsically different in SLE patients compared with healthy controls. Different triggers related to innate and adaptive immunity activate platelets which release extracellular vesicles, soluble factors and interact with immune cells, thereby perpetuating inflammation. Platelets are involved in organ damage in SLE, especially in lupus nephritis and participate in the heightened cardiovascular mortality. They also play a clear role in antiphospholipid syndrome which can be associated with both thrombocytopenia and thrombosis. To tackle platelet activation and their interactions with immune cells now constitute promising therapeutic strategies in SLE.

Review and prospects of targeted therapies for Spleen tyrosine kinase (SYK)

Spleen tyrosine kinase (SYK) is a non-receptor tyrosine kinase. The dysregulation of SYK is closely related to the occurrence and development of allergic diseases, autoimmune diseases and cancer. SYK has become an attractive target for drug discovery due to its important biological functions. This article reviews the biological function of SYK, the relationship between SYK and disease, and therapies targeting SYK. In addition, inspired by new technologies such as proteolysis targeting chimeras (PROTACs) and phosphatase recruiting chimeras (PHORCs), we propose the development of new therapeutic approaches for targeting SYK, such as SYK PROTACs and SYK PHORCs, which may overcome deficiencies of existing methods.

Fragility fractures in lupus patients: Associated factors and comparison of four fracture risk assessment tools

OBJECTIVE

Osteoporosis (OP) and fragility fractures (FF) are common comorbidities in patients with systemic lupus erythematosus (SLE). This study aimed to (1) assess the prevalence of these conditions in a cohort of SLE patients (2) evaluate the risk factors associated with FF, and (3) compare the accuracy of four different FF risk assessment algorithms to determine which performs better in this specific rheumatologic population.

MATERIALS AND METHODS

We conducted a cross-sectional study with SLE women who underwent bone mineral density assessment by dual-energy X-ray absorptiometry (DEXA) within 3 months of their last visit. Conventional radiology methods were used to evaluate the presence of FF. The 10-year risk of osteoporotic fractures was estimated using four tools: DeFRA, FRAX (adjusted for GC dosage), GARVAN, and QFracture. The comparison of these computational tools was analyzed by the area under the receiver operating characteristic (ROC) curves.

RESULTS

We analyzed 86 SLE patients with a median age of 56 years (IQR 12.1) and a median age at diagnosis of 34 years (IQR 17.2). The median T-score values at the femoral neck and lumbar spine were -1.6 (IQR 0.9) and -1.7 (IQR 1.1), respectively. Of the patients, 33 (38.4%) had OP, with 13 patients (15.1%) experiencing FF. Univariate analysis showed that the presence of FF was associated with thrombocytopenia (p = .01), hemolytic anemia (p = .0001), and the intake of cyclosporine A (p = .002), cyclophosphamide (p = .006), and rituximab (p = .001). The median 10-year risk of major FF for the four calculation tools were as follows: DeFRA 9.85 (IQR 8.6); FRAX GC 8.8 (IQR11.7); GARVAN 12 (IQR 8.2); QFracture 4.1 (IQR 5.8). We observed a significant correlation among all instruments evaluated (p < .0001); in particular, the best correlation was recorded between the FRAX GC and the DeFRA (r = 0.85). DeFRA was the best tool for this population with an AUC of 0.94 (p < .0001, CI 0.88-1).

CONCLUSIONS

OP is a common comorbidity in SLE patients, even in younger patients. FF appears to be more frequent in patients with hematologic involvement. The comparison of the four algorithms shows that DeFRA is the most accurate tool and should be applied to SLE patients.

Current Treatment Approach, Emerging Therapies and New Horizons in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE), the prototype of systemic autoimmune diseases is characterized by extreme heterogeneity with a variable clinical course. Renal involvement may be observed and affects the outcome. Hydroxychloroquine should be administered to every lupus patient irrespective of organ involvement. Conventional immunosuppressive therapy includes corticosteroids, methotrexate, cyclophosphamide, mycophenolate mofetil, azathioprine, cyclosporine and tacrolimus. However, despite conventional immunosuppressive treatment, flares occur and broad immunosuppression is accompanied by multiple side effects. Flare occurrence, target organ involvement, side effects of broad immunosuppression and increased knowledge of the pathogenetic mechanisms involved in SLE pathogenesis as well as the availability of biologic agents has led to the application of biologic agents in SLE management. Biologic agents targeting various pathogenetic paths have been applied. B cell targeting agents have been used successfully. Belimumab, a B cell targeting agent, has been approved for the treatment of SLE. Rituximab, an anti-CD20 targeting agent is also used in SLE. Anifrolumab, an interferon I receptor-targeting agent has beneficial effects on SLE. In conclusion, biologic treatment is applied in SLE and should be further evaluated with the aim of a good treatment response and a significant improvement in quality of life.

Development of systemic lupus erythematosus in patients with immune thrombocytopenic purpura: A systematic meta-analysis

BACKGROUND

Recent population-based cohort studies suggest that the incidence of systemic lupus erythematosus (SLE) is increased in patients with immune thrombocytopenic purpura (ITP). We performed a systematic review and meta-analysis to evaluate the development of SLE in patients with ITP.

METHODS

Literature search was performed in PubMed, Web of Science and Cochrane Library for studies published prior to October 2022. Studies were included that reported development of SLE in ITP patients. Forest plot was used to detect overall SLE frequency in ITP and compare risk ratios for SLE development in different ITP subgroups. Study heterogeneity was assessed by using I2 statistics.

RESULTS

26 eligible studies comprising 14867 ITP patients were included in analysis. 311 ITP patients developed SLE during the follow-up period (range: 1.1-14 years) (2.09%, 95%CI: 1.87-2.33). Relative risk (RR) for developing SLE was significantly higher in female ITP patients (RR: 4.23, 95%CI: 2.52-7.12, p < 0.0001). Anti-nuclear antibody (ANA) was reported in 23 studies, there were 766/4377 ANA positive patients with ITP (17.5%). The risk of SLE development in ANA positive ITP patients was significant (RR: 26.29, 95%CI: 14.45-47.81, p < 0.0001).

CONCLUSIONS

Our study suggests ITP patients are at high risk of developing SLE in future. Pooled data revealed that females and patients with a positive ANA titer are at a significantly high risk of developing SLE.