Sex Differences in Systemic Lupus Erythematosus: Epidemiology, Clinical Considerations, and Disease Pathogenesis

Proteomic Analyses Reveal Higher Levels of Neutrophil Activation in Men Than in Women With Systemic Lupus Erythematosus

Objective

Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disease that displays a significant gender difference in terms of incidence and severity. However, the underlying mechanisms accounting for sexual dimorphism remain unclear. The aim of this work was to reveal the heterogeneity in the pathogenesis of SLE between male and female patients.

Methods

PBMC were collected from 15 patients with SLE (7 males, 8 females) and 15 age-matched healthy controls (7 males, 8 females) for proteomic analysis. The proteins of interest were validated in independent samples (6 male SLE, 6 female SLE). Biomarkers for neutrophil activation (calprotectin), neutrophil extracellular traps (cell-free DNA and elastase), and reactive oxygen species (glutathione) were measured, using enzyme-linked immunosorbent assay, in plasma obtained from 52 individuals.

Results

Enrichment analysis of proteomic data revealed that type I interferon signaling and neutrophil activation networks mapped to both male and female SLE, while male SLE has a higher level of neutrophil activation compared with female SLE. Western blot validated that PGAM1, BST2, and SERPINB10 involved in neutrophil activation are more abundant in male SLE than in female SLE. Moreover, biomarkers of neutrophil activation and reactive oxygen species were increased in male SLE compared with female SLE.

Conclusion

Type I interferon activation is a common signature in both male and female SLE, while neutrophil activation is more prominent in male SLE compared with female SLE. Our findings define gender heterogeneity in the pathogenesis of SLE and may facilitate the development of gender-specific treatments.

Assessing the cardiovascular risk in patients with systemic lupus erythematosus: QRISK and GAPSS scores head-to-head

OBJECTIVES

We aimed to apply and compare the QRISK3 and the adjusted Global AntiPhospholipid Syndrome (APS) Score (aGAPSS) in a cohort of systemic lupus erythematosus (SLE) patients, with and without a concomitant diagnosis of APS, in order to assess their augmented risk of developing cardiovascular diseases (CVDs).

METHODS

Patients (25-85 yo) with a diagnosis of SLE and/or of Secondary APS (SAPS) were included. QRISK3 was calculated using the official online calculator; aGAPSS using the validated point-values based on aPL-profile and independent risk factors.

RESULTS

The cohort included 142 SLE patients: 34 SAPS (23.9%) and 108 SLE patients without APS (76.1%).When considering all the cohort, patients with cerebrovascular/coronary events showed higher values of aGAPSS (10.1 ± 6.2 vs. 5.8 ± 6.1; p = 0.007), but not of the QRISK3. Furthermore, a significant association was observed between the occurrence of these events and high-risk aGAPSS: p = 0.03 for aGAPSS≥8, p = 0.01 for aGAPSS ≥9, p = 0.008 for aGAPSS ≥10. aGAPSS strongly correlated with the occurrence of any thrombotic event, both at the uni- and multivariate analysis (p = 0.012 and p = 0.009). Male gender also resulted to positively correlate with the occurrence of any thrombotic event at both uni- and multivariate analysis (p = 0.017 and p = 0.03). Focusing on aPL-profile, regardless the diagnosis, we found a statistical significance only for aGAPSS (aPL+ =9.6 ± 6.3 vs. aPL- = 4.1 ± 5.1; p < 0.001).

CONCLUSIONS

Despite QRISK3 being more accurate than traditional risk score in predicting CVD risk in SLE patients, aGAPSS appears to be the most valuable tool for this purpose.

Risk of Autoimmune Diseases Following Optic Neuritis: A Nationwide Population-Based Cohort Study

Objectives

Optic neuritis is (ON) is believed to be an immune-mediated disease; however, the association between optic neuritis and autoimmune diseases remains unclear. This study aimed to identify the incidence rate and adjusted hazard ratio (aHR) of autoimmune diseases in patients with optic neuritis.

Methods

This nationwide, population-based, retrospective cohort study collected patients’ data between 1999 and 2013 from the National Health Insurance Research Database in Taiwan. A total of 9,235 patients were included. Using 1:4 propensity scoring, 1,847 patients were enrolled in the optic neuritis group and 7,388 in the non-optic neuritis group according to age, sex, comorbidities, and corticosteroid use. Follow-up was started from the index date and the endpoint was a diagnosis of new-onset autoimmune diseases including, myasthenia gravis (MG), psoriatic arthritis (PsA), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and ankylosing spondylitis (AS).

Results

The Kaplan-Meier curves depicted that patients with optic neuritis had a higher cumulative incidence of autoimmune diseases than patients without optic neuritis. Cox proportional hazard regression showed that patients with optic neuritis were at a high risk of autoimmune diseases (aHR: 1.40; 95% C.I., 1.05–1.87), including MG (aHR: 4.16, 95% C.I.: 1.33–12.94), SLE (aHR: 3.33, 95% C.I.: 1.24–8.97), and AS (aHR: 2.86, 95% C.I.: 1.54–5.31). Subgroup analysis provided that patients with optic neuritis aged below 65 years (aHR: 1.42, 95% C.I.: 1.03–1.96) or who were females (aHR: 1.59, 95% C.I.: 1.11–2.27) had a significantly increased risk of autoimmune diseases compared to respective controls. The use of corticosteroids reduced the risk of autoimmune diseases in patients with optic neuritis (aHR for corticosteroids non-users: 1.46, 95% C.I.: 1.03–2.07).

Conclusion

Patients with optic neuritis presented with a high risk of autoimmune diseases such as MG, SLE, and AS, especially patients with optic neuritis who were young or females. Corticosteroids attenuated the link between optic neuritis and subsequent autoimmune diseases.

The role of environmental exposures and gene-environment interactions in the etiology of systemic lupus erythematous

Systemic lupus erythematosus (SLE) is a complex, chronic autoimmune disease, whose etiology includes both genetic and environmental factors. Individual genetic risk factors likely only account for about one-third of observed heritability among individuals with a family history of SLE. A large portion of the remaining risk may be attributable to environmental exposures and gene-environment interactions. This review focuses on SLE risk associated with environmental factors, ranging from chemical and physical environmental exposures to lifestyle behaviors, with the weight of evidence supporting positive associations between SLE and occupational exposure to crystalline silica, current smoking, and exogenous estrogens (e.g., oral contraceptives and postmenopausal hormones). Other risk factors may include lifestyle behaviors (e.g., dietary intake and sleep) and other exposures (e.g., ultraviolet [UV] radiation, air pollution, solvents, pesticides, vaccines and medications, and infections). Alcohol use may be associated with decreased SLE risk. We also describe the more limited body of knowledge on gene-environment interactions and SLE risk, including IL-10, ESR1, IL-33, ITGAM, and NAT2 and observed interactions with smoking, UV exposure, and alcohol. Understanding genetic and environmental risk factors for SLE, and how they may interact, can help to elucidate SLE pathogenesis and its clinical heterogeneity. Ultimately, this knowledge may facilitate the development of preventive interventions that address modifiable risk factors in susceptible individuals and vulnerable populations.

Molecular mechanisms controlling age-associated B cells in autoimmunity

Age-associated B cells (ABCs) have emerged as critical components of immune responses. Their inappropriate expansion and differentiation have increasingly been linked to the pathogenesis of autoimmune disorders, aging-associated diseases, and infections. ABCs exhibit a distinctive phenotype and, in addition to classical B cell markers, often express the transcription factor T-bet and myeloid markers like CD11c; hence, these cells are also commonly known as CD11c+ T-bet+ B cells. Formation of ABCs is promoted by distinctive combinations of innate and adaptive signals. In addition to producing antibodies, these cells display antigen-presenting and proinflammatory capabilities. It is becoming increasingly appreciated that the ABC compartment exhibits a high degree of heterogeneity, plasticity, and sex-specific regulation and that ABCs can differentiate into effector progeny via several routes particularly in autoimmune settings. In this review, we will discuss the initial insights that have been obtained on the molecular machinery that controls ABCs and we will highlight some of the unique aspects of this control system that may enable ABCs to fulfill their distinctive role in immune responses. Given the expanding array of autoimmune disorders and pathophysiological settings in which ABCs are being implicated, a deeper understanding of this machinery could have important and broad therapeutic implications for the successful, albeit daunting, task of targeting these cells.

Does Gender Affirming Hormone Therapy Increase the Risk of Kidney Disease?

Kidney health and manifestation of disease in transgender men, women, and nonbinary individuals are not well understood. Transgender individuals commonly receive gender-affirming hormone therapy (GAHT) to align their outward appearance with their gender. Recent attention to the differences in fundamental kidney parameters has identified that transgender individuals may manifest levels of these biomarkers differently than their cisgender counterparts. Improving understanding of the differences in biomarkers and in the development of kidney disease is essential to providing appropriate kidney care to this vulnerable population. In this review, we introduce the current information related to GAHT and kidney health and highlight the significant gaps in our understanding of how GAHT may affect kidney physiology and pathophysiology.

Hormone therapy effect on menopausal systemic lupus erythematosus patients: a systematic review

Systemic lupus erythematosus (SLE) primarily affects women, who may need hormone therapy (HT) in menopause. There is, however, some concern as to its efficacy and safety. This systematic review aimed to determine the effect of HT on the activity of SLE and its safety. The study was a qualitative systematic review. Research was conducted with data retrieved from Embase, MEDLINE and Cochrane databases using MESH terms up to April 2021, with no bar on date or language. Sixteen studies were selected for analysis. Most of them showed HT to be effective in the treatment of menopausal symptoms with no impact in SLE activity, but one randomized clinical trial showed an increase in the number of thrombotic events. The present systematic review demonstrated the efficacy of HT for treating the menopausal symptoms of SLE patients. The risk of flare and thrombosis seems to be very low.

Predictors Associated with Adverse Pregnancy Outcomes in a Cohort of Women with Systematic Lupus Erythematosus from Romania-An Observational Study (Stage 2)

Background: Pregnancy in women with systemic lupus erythematosus (SLE) is accompanied by adverse pregnancy outcomes (APOs). We aimed to investigate the association between clinical, sonographic, and laboratory parameters and APOs (preeclampsia, intrauterine growth restriction, premature birth, and maternal mortality). Methods: This observational retrospective study included all pregnancies in women with SLE who attended two tertiary maternity hospitals from Romania between January 2013 and December 2020. Clinical, sonographic, and laboratory variables were examined. Bivariate associations of APO status and each predictor variable were evaluated, and significant predictors were further included in a classification model based on discriminant analysis. Results: Predictors of APOs included BMI > 25 kg/m2, personal history of lupus nephritis or chronic hypertension, proteinuria, low C3, SLE Disease Activity Index 2000 (SLEDAI-2k score ≥ 4 and physician’s global-assessment (PGA) score ≥ 1 throughout pregnancy, increased mean uterine arteries pulsatility index in the first and second trimesters, cerebroplacental ratio < 1 in the second and third trimesters, and small fetal abdominal circumference in the third trimester. Glucocorticoids, methyldopa, and aspirin use appeared to be protective against APOs. Conclusions: This study provides a comprehensive analysis of the most important predictors for APOs in pregnant patients with SLE, which could constitute a basis for further research.

Animal models of systemic lupus erythematosus and their applications in drug discovery

INTRODUCTION

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with substantial phenotypic heterogeneity. Currently, our understanding of the pathogenesis is still limited, and as a result, specific and efficacious therapies are lacking. Various mouse models have been established to serve as powerful tools that will promote a better understanding of the disease and the ability to test novel drugs before clinical application.

AREAS COVERED

The authors review the existing mouse models of SLE in terms of pathogenesis and manifestations, as well as their applications in drug discovery and development. The areas of focus include promising novel therapeutics that could benefit patients in the future and the contribution of mouse models used in preclinical studies.

EXPERT OPINION

Given the diversity of SLE mouse models with different characteristics, researchers must select a suitable model based on the mechanism involved. The use of multiple models is needed for drug testing studies to evaluate drug efficacy on different genetic backgrounds and other mechanisms to provide a reference for clinical trials.

A tissue-selective estrogen complex as treatment of osteoporosis in experimental lupus

Osteoporosis is a common secondary complication in patients with systemic lupus erythematosus (SLE). Current osteoporosis treatment with bisphosphonates has some negative side effects and there is a lack of data regarding newer treatments options for SLE associated osteoporosis. The tissue-selective estrogen complex (TSEC) containing conjugated estrogens and the selective estrogen receptor modulator bazedoxifene (Bza) is approved for treatment of postmenopausal vasomotor symptoms and prevention of osteoporosis. However, it has not been evaluated for treatment of osteoporosis in postmenopausal SLE patients. Ovariectomized MRL/lpr mice constitute a model for postmenopausal lupus that can be used for osteoporosis studies. We used this model in a set of experiments where the mice were treated with different doses of 17β-estradiol-3-benzoate (E2), Bza, or TSEC (E2 plus Bza), administered in the early or late phases of disease development. The skeleton was analyzed by dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and high-resolution microcomputed tomography. The lupus disease was assessed by determination of proteinuria, hematuria, and lupus disease markers in serum. Treatment with medium dose TSEC administered in early disease protected ovariectomized MRL/lpr mice from trabecular bone loss, while there were no differences in lupus disease parameters between treatments. This is the first experimental study to investigate TSEC as a potential new therapy for osteoporosis in postmenopausal SLE.

An evaluation of costs associated with overall organ damage in patients with systemic lupus erythematosus in the United States

INTRODUCTION

Approximately 33-50% of patients with systemic lupus erythematosus (SLE) develop organ damage within 5 years of diagnosis. Real-world studies that capture the healthcare resource utilization (HCRU) and costs associated with SLE-related organ damage are limited. The aim of this study was to evaluate HCRU and costs associated with organ damage in patients with SLE in the USA.

METHODS

This retrospective study (GSK study 208380) used the PharMetrics Plus administrative claims database from 1 January 2008 to 30 June 2019. Patients with SLE and organ damage were identified using International Classification of Diseases (ICD)-9/10 codes derived from the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. The first observed diagnosis of organ damage was designated as the index date. Selection criteria included: ≥18 years of age; ≥1 inpatient or ≥2 outpatient claims for SLE (≥30 days apart before the index date; ICD-9: 710.0 or ICD-10: M32, excluding M32.0); ≥1 inpatient or ≥3 outpatient claims for organ damage within 6 months for the same organ system code; continuous enrollment of 12 months both pre- and post-index date. The proportion of patients with new organ damage, disease severity, SLE flares, SLE-related medication patterns, HCRU and all-cause costs (2018 US$) were assessed 12 months pre- and post-index date.

RESULTS

Of the 360,803 patients with a diagnosis of SLE, 8952 patients met the inclusion criteria for the presence of new organ damage. Mean (standard deviation (SD)) age was 46.4 (12.2) years and 92% of patients were female. The most common sites of organ damage were neuropsychiatric (22.0%), ocular (12.9%), and cardiovascular (11.4%). Disease severity and proportion of moderate/severe flare episodes significantly increased from pre- to post-index date (p < 0.0001). Overall, SLE-related medication patterns were similar pre- versus post-index date. Inpatient, emergency department and outpatient claims increased from pre- to post-index date and mean (SD) all-cause costs were 71% higher post- versus pre-index date ($26,998 [57,982] vs $15,746 [29,637], respectively).

CONCLUSIONS

The economic impact associated with organ damage in patients with SLE is profound and reducing or preventing organ damage will be pivotal in alleviating the burden for patients and healthcare providers.

Epidemiology of Antiphospholipid Syndrome in the General Population

Purpose of Review

The epidemiology of antiphospholipid syndrome (APS) is poorly understood. Here, we review the current understanding of the epidemiology of antiphospholipid syndrome in the general population and the frequency of antiphospholipid antibodies in the general population in patients with obstetric morbidity, arterial events, and venous thromboembolism.

Recent Findings

There have been few population-based studies that estimated the prevalence and incidence of APS. The estimated incidence and prevalence among most these studies ranged between 1 and 2 cases per 100,000 and 40 and 50 cases per 100,000 respectively. The prevalence of antiphospholipid antibodies in patients with obstetric morbidity was 6–9%, while in arterial events and venous thromboembolism is 9–10%. However, this data remains limited. Mortality of patients with APS is 50–80% higher than the general population.

Summary

The epidemiology of APS has been difficult to elucidate. Population-based studies patients with diverse age, racial, and ethnic backgrounds are needed.

Male systemic lupus erythematosus: Two distinct presentations

Systemic lupus erythematosus (SLE) multisystem autoimmune disease is characterised by a series of exacerbations and remissions. Tissues of multiple-organ systems are affected by autoantibodies. We report here two cases of SLE in male patients. Being rarer in males, diagnosis is often delayed and associated with poorer outcomes. An alert primary care physician can be instrumental in early diagnosis and ensuring better outcomes.

Positive antithyroid antibody predicts severity of neuromyelitis optica spectrum disorder in children

BACKGROUND

Neuromyelitis optica spectrum disease (NMOSD) is a rare autoimmune disease, which can coexist with autoimmune thyroid diseases (AITDS). There has been no report on the clinical characteristics of NMOSD in children with positive anti-thyroid antibodies (ATAbs). The aim of this study is to evaluate thyroid function and detect the difference between ATAbs seropositive and seronegative NMOSD children.

METHODS

108 children with a confirmed diagnosis of NMOSD who were admitted to Shengjing Hospital of China Medical University from January 2015 to September 2020 were enrolled and their thyroid functions were evaluated. They were divided into two groups by ATAbs abnormalities. Their demographic characteristics, clinical symptoms, laboratory and MRI scan results of the brain and spinal cord were assessed.

RESULTS

ATAbs positive rate was higher in children with NMOSD when compared with healthy controls (P < 0.05). Most NMOSD children with positive ATAbs were female (P < 0.01). The expanded disability status scale (EDSS) score was significantly higher in the ATAbs positive group (P < 0.01). There were statistically significant differences for the incidence of bulbar area postrema symptoms, spinal cord symptoms, and fever of unknown origin of the first onset between the ATAbs positive and negative group (P < 0.05). The ANA and MOG antibody positive rate, longitudinally extensive transverse myelitis (LETM), and electroencephalogram (EEG) were significantly higher in ATAbs positive group (P < 0.05).

CONCLUSION

MOG antibody-positive is a unique marker of aggravation of neurological dysfunction in ATAbs-positive NMOSD children. Monitoring ATAbs may play an important role in predicting the prognosis of NMOSD.

Hygiene Hypothesis as the Etiology of Kawasaki Disease: Dysregulation of Early B Cell Development

Kawasaki disease (KD) is an acute systemic vasculitis that occurs predominantly in children under 5 years of age. Despite much study, the etiology of KD remains unknown. However, epidemiological and immunological data support the hygiene hypothesis as a possible etiology. It is thought that more sterile or clean modern living environments due to increased use of sanitizing agents, antibiotics, and formula feeding result in a lack of immunological challenges, leading to defective or dysregulated B cell development, accompanied by low IgG and high IgE levels. A lack of B cell immunity may increase sensitivity to unknown environmental triggers that are nonpathogenic in healthy individuals. Genetic studies of KD show that all of the KD susceptibility genes identified by genome-wide association studies are involved in B cell development and function, particularly in early B cell development (from the pro-B to pre-B cell stage). The fact that intravenous immunoglobulin is an effective therapy for KD supports this hypothesis. In this review, I discuss clinical, epidemiological, immunological, and genetic studies showing that the etiopathogenesis of KD in infants and toddlers can be explained by the hygiene hypothesis, and particularly by defects or dysregulation during early B cell development.

Impact of menopause on women with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by chronic and systemic inflammation affecting multiple organ systems, including an increased risk of cardiovascular disease due to the SLE-associated hyperinflammatory state. SLE shows a strong female predominance, suggesting a potential role of sex hormones in the pathogenesis of the disease. Evidence suggests an earlier age of menopause among women with SLE, despite mixed findings regarding other markers of ovarian aging. In healthy populations, the menopausal transition is associated with important physiologic changes resulting in increased cardiometabolic risk and risk of osteoporosis. Thus, women with SLE who experience the inflammatory effects of the autoimmune condition combined with the (potentially earlier) menopausal transition may represent a particularly vulnerable group of individuals during a particular window of time. Little is known, however, about strategies for cardiovascular risk or bone loss mitigation in women with SLE during the menopausal transition. Further, despite lack of knowledge regarding the burden of menopausal symptoms in women with SLE, existing recommendations provide only cautionary guidance for the use of hormone replacement therapy to address menopausal symptoms in this population. Importantly, the data regarding both SLE and menopause-associated cardiovascular and osteoporotic risk demonstrate the critical need for additional research to identify the type and timing of treatments or interventions needed to best mitigate this increased risk.

CD38 Correlates with an Immunosuppressive Treg Phenotype in Lupus-Prone Mice

CD38 is a transmembrane glycoprotein expressed by T-cells. It has been reported that patients with systemic lupus erythematosus (SLE) showed increased CD38⁺CD25⁺ T-cells correlating with immune activation and clinical signs. Contrariwise, CD38 deficiency in murine models has shown enhanced autoimmunity development. Recent studies have suggested that CD38⁺ regulatory T-cells are more suppressive than CD38⁻ regulatory T-cells. Thus, we have suggested that CD38 overexpression in SLE patients could play a role in regulating immune activation cells instead of enhancing it. This study found a correlation between CD38 with FoxP3 expression and immunosuppressive molecules (CD69, IL-10, CTLA-4, and PD-1) in T-cells from lupus-prone mice (B6.MRL-Fas^lpr/J). Additionally, B6.MRL-Fas^lpr/J mice showed a decreased proportion of CD38⁺ Treg cells regarding wild-type mice (WT). Furthermore, Regulatory T-Cells (Treg cells) from CD38-/- mice showed impairment in expressing immunosuppressive molecules and proliferation after stimulation through the T-cell receptor (TCR). Finally, we demonstrated an increased ratio of IFN-γ/IL-10 secretion in CD38-/- splenocytes stimulated with anti-CD3 compared with the WT. Altogether, our data suggest that CD38 represents an element in maintaining activated and proliferative Treg cells. Consequently, CD38 could have a crucial role in immune tolerance, preventing SLE development through Treg cells.

Temporal and spatial changes in cerebral blood flow in neuropsychiatric systemic lupus erythematosus: a subtraction brain spect study

This study was addressed to evaluate the temporal and spatial changes in regional cerebral blood flow (rCBF) of patients with neuropsychiatric systemic lupus erythematosus (NPSLE). Our objective was to correlate the subtracted SPECT coregistered to MRI features (SISCOM) with demographic, clinical and laboratory findings to shed light upon the pathophysiological evolution of the NPSLE. Twenty-six NPSLE patients with MRI and pre- and post-treatment brain SPECT with [99mTc]Tc-ECD. SISCOM features were categorized as improvement, worsening, activation and/or deactivation of rCBF findings. Patients mean age of 43.19 years and 65.38% white were evaluated. The patients mean age at onset of SLE was 26.05 and 42.29 for NPSLE. The mean time between the onset of SLE and first NPSLE symptoms was 05.57 years. The disease has already been initiated as NPSLE in 4 patients. The SLEDAI average score was 31.69 and the SLICC/ACR-DI score was 06.96. The patients underwent an average of 09.23 cyclophosphamide. The SISCOM findings showed functional and pathological states on different brain regions. The rCBF changes were not associated with index scores. There was, however, a trend towards an association between lower SLEDAI scores with improvement and higher SLEDAI with worsening in SISCOM, Also a trend of association between lower SLICC score with improvement, and higher SLICC with worsening. The female gender was predictive of activation and worsening, separately, and deactivation and worsening in a set. Non-white patients were predictive of worsening. The seizure was predictive of deactivation separately, and deactivation and worsening in a set. Finally, normal C3 was a predictor of improvement. The present study showed dynamic brain changes in NPSLE patients. SISCOM technique showed improved rCBF in some brain areas, and worsening, activation and deactivation in others. There were associations between rCBF changes and gender, skin colour and complement C3 and association trends with SLEDAI and SLICC scores.

The Economic Burden of Lupus Nephritis: A Systematic Literature Review

INTRODUCTION

Few studies have evaluated the economic burden of lupus nephritis (LN). The aim of this systematic literature review (SLR) was to assess the economic burden (direct and indirect costs, and healthcare resource utilization [HCRU]) associated with LN, with particular focus on the burden of renal flares and end-stage kidney disease (ESKD).

METHODS

This SLR (GSK study 213531) was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Searches of the MEDLINE and Embase databases were conducted for English language publications reporting cost or HCRU data in patients with LN (regardless of age or LN histological class) until December 10, 2019. Handsearching of conference proceedings and keyword-based searches in PubMed, Google, and Google Scholar were also conducted.

RESULTS

Twenty-two studies were identified from 28 publications reporting the cost (n = 19) and HCRU (n = 13) associated with LN. Most studies were from North America (n = 13) and many used administrative claims data (n = 9). LN was associated with substantially higher direct costs (e.g., total annual, hospitalization, and ESKD-related direct costs), total indirect costs, and HCRU (e.g., hospitalization, outpatient services, and medication use) compared with patients without systemic lupus erythematosus (SLE) or non-renal SLE controls. ESKD and dialysis were significant contributors to economic burden. No studies described the cost of renal flares.

CONCLUSIONS

The consensus across the 22 studies was that the economic burden of LN is substantial, particularly in active or severe disease, or if there is progression to ESKD. Total direct cost may be underestimated in claims data given the challenges of identifying patients with LN. Further studies are vital to ascertain the cost of renal flares; a renal flare is likely to result in a period of increased HCRU, which could be mitigated by treatments that extend renal remission.

Variability of the rs333 in Polish patients with lupus erythematosus

Introduction

Lupus erythematosus (LE) is an autoimmune disease with a strong influence of genetic and environmental factors. C-C motif chemokine receptor 5 (CCR5) gene expression may affect the development and intensity of LE.

Aim

To evaluate the possible association between the 32bp deletion in rs333 locus located within the CCR5 gene and the development of LE or the occurrence of various clinical symptoms in the course of the disease.

Material and methods

One hundred and twenty patients with LE (77 with systemic lupus erythematosus (SLE) and 43 with discoid lupus erythematosus (DLE)) and 100 healthy controls from the Polish population were genotyped for deletion in rs333.

Results

32 bp deletion in the rs333 was significantly more frequent among healthy individuals than DLE patients. Moreover, heterozygotes and homozygotes with deletion in rs333 were significantly more frequent within the control group than the group of patients with discoid lupus erythematosus. In contrast, any statistically significant differences in allele or genotype frequencies between healthy persons and SLE patients were observed. Furthermore, nucleotide sequence variability of rs333 was not associated with certain clinical symptoms of LE patients.

Conclusions

Deletion in the rs333 might be a protective factor for DLE, but not SLE in the Polish population. Nevertheless further studies performed on larger populations are needed to confirm these observations.

The Development and Usability Assessment of an mHealth Application to Encourage Self-Care in Pregnant Women against COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has caused serious concerns in pregnant women. Self-care mHealth applications can provide helpful guidelines for COVID-19 prevention or management in case of infection. This study aimed to develop and then assess a self-care smartphone-based application to provide self-care for pregnant women against COVID-19. The present study was conducted in two phases. First, a needs assessment was performed based on the opinions of 30 obstetricians and pregnant women. Then, relying on the results, a smartphone-based application was prototyped and assessed in terms of its usability and user satisfaction. To assess the application, 36 pregnant women (11 infected with COVID-19) were asked to use the application for a week. The QUIS questionnaire 5.5 was used for assessment, and the results were analyzed via descriptive statistics in SPSS 23. According to the obstetricians and pregnant women, of the 41 information requirements, 35 data elements were noted to be essential in the needs assessment. Features of the application were placed in four categories of User's Profile, Lifestyle, Disease Management and Control, and Application Functions (e.g., introducing high-risk places in terms of COVID-19 prevalence in each city, introducing specialized COVID-19 medical centers to pregnant women to receive services, medication management, stress management and control, nutrition and diet management, sleep management, contacting physicians, doctor's appointment reminder, searching the available educational materials, and making application adjustments such as text font, size, and color). With an average score of 7.94 (out of 9), pregnant women rated the application at a good level. The application can be used to reduce anxiety and stress about COVID-19 in mothers, provide access to reliable information to answer possible questions, identify high-risk locations, and provide pregnant women with instant access to healthcare facilities and information related to COVID-19 self-care processes.

Association of DYNC1H1 gene SNP/CNV with disease susceptibility, GCs efficacy, HRQOL, anxiety, and depression in Chinese SLE patients

Background

Systemic lupus erythematosus is a heterogeneous autoimmune disease characterized by multi‐system injuries and overproduction of autoantibodies. There are many genetic studies on SLE, but no report has considered the relationship between cytoplasmic dynein and SLE susceptibility.

Objectives

Our study intends to investigate whether DYNC1H1 gene SNP/CNV is related to SLE susceptibility, GCs efficacy, HRQOL, anxiety, and depression in Chinese SLE patients.

Methods

A total of 502 cases and 544 healthy controls were recruited into the case‐control study, and 472 subjects from the case group were followed up for 12 weeks to evaluate GCs efficacy, HRQOL, anxiety, and depression. Multiplex SNaPshot technique was applied to genotype the seven SNPs of DYNC1H1, and AccuCopy^TM method was conducted to quantify the copy number of DYNC1H1. Anxiety and depression were evaluated using HAMA and HAMD‐24 scales, respectively. The SF‐36 scale was used to assess HRQOL.

Results

The significant association between SNP rs1190606 and SLE susceptibility was displayed in the dominant model (P_BH = 0.004) as well as its allele model (P_BH = 0.004). We also found that SNP rs2273440 was related to photosensitization symptom in SLE patients (P_BH = 0.032). In the follow‐up study, SNP rs11160668 was connected with the improvement of BP in male patients (P_BH = 0.011). However, no association of DYNC1H1 gene with GCs efficacy, anxiety, and depression was found. No CNV in DYNC1H1 was detected.

Conclusions

The study suggests that DYNC1H1 gene polymorphisms may have an effect on SLE susceptibility and BP improvement of HRQOL in Chinese SLE patients.

Association between depression and sleep quality in patients with systemic lupus erythematosus: a systematic review and meta-analysis

Background

Currently, there is no consistent understanding of the relationship between depression and sleep quality in patients with systemic lupus erythematosus (SLE). This study aimed to explore the correlation between depression and sleep quality in SLE patients.

Methods

Five English (PubMed, Web of Science, EMBASE, Cochrane Library, and CINAHL) databases were systematically searched from inception to January 12, 2021. Two authors independently screened publications and extracted data according to set inclusion and exclusion criteria. Statistical analyses were performed with STATA 16.0. Data were pooled using a random-effects model.

Results

A total of 9 identified studies matched the inclusion criteria, reporting on 514 patients with SLE in the analysis. A moderate correlation of depression with sleep quality was found (pooled r = 0.580 [0.473, 0.670]). Compared to good sleepers, patients with SLE and poor sleep quality had higher levels of depression (standardized mean difference =  − 1.28 [− 1.87, − 0.69]). Depression was associated with subjective sleep quality (r = 0.332 [0.009, 0.592]), sleep latency (r = 0.412 [0.101, 0.649]), sleep disturbances (r = 0.405 [0.094, 0.645]), daytime dysfunction (r = 0.503 [0.214, 0.711]), the four dimensions of Pittsburgh Sleep Quality Index (PSQI), while no significant correlation was found in the other three PSQI dimensions.

Conclusion

Depression had a moderate correlation with sleep quality in patients with SLE. Patients with poor sleep quality tended to have higher level of depression than that of good sleepers. Awareness of the correlation may help rheumatology physicians and nurses to assess and prevent depression and improve sleep quality in patients with SLE.

Role of clinicopathological features for the early prediction of prognosis in lupus nephritis

Ambiguities remain regarding the role of clinicopathological characteristics in the early prediction of the prognosis of lupus nephritis (LN). Systemic lupus erythematosus (SLE) patients who completed routine follow-up were identified and retrospectively reviewed for eligible cases. Poor prognosis was defined as all-cause mortality or a persistent decrease of eGFR greater than half the baseline level or progression to end-stage renal disease (ESRD). An optimal Cox regression model was constructed for the early prediction of a poor prognosis for LN. Among the 2163 SLE patients, 376 eligible LN cases were enrolled in the study, with a median follow-up time of 55 [27.0, 87.0] months. The male-to-female ratio was 1:7.2, and 37 patients (9.8%) progressed to the composite endpoint. The ISN/RPS class was significantly associated with proteinuria levels (P-value < 0.001), and class IV/IV + V patients, but not class V patients, had the most severe proteinuria. Our optimal multivariate Cox regression model indicated that sex, ISN/RPS class, tubular atrophy/interstitial fibrosis, serum albumin, tertiles of proteinuria, and their interaction were independently associated with a poor prognosis. ROC analysis and external validation demonstrated that our model was efficient and robust for distinguishing LN patients with a poor prognosis. Our study constructed a robust and early predictive model for convenience in clinical practice to identify poor prognosis in LN patients. We found a significant interaction effect between proteinuria and serum albumin for the prediction of poor prognosis. LN patients with low-level proteinuria and hypoalbuminemia exhibit an increased hazard of progression to poor outcomes.

Aberrant Gut Microbiome Contributes to Intestinal Oxidative Stress, Barrier Dysfunction, Inflammation and Systemic Autoimmune Responses in MRL/lpr Mice

Microbiome composition and function have been implicated as contributing factors in the pathogenesis of autoimmune diseases (ADs), including systemic lupus erythematosus (SLE), rheumatoid arthritis and autoimmune hepatitis (AIH). Furthermore, dysbiosis of gut microbiome is associated with impaired barrier function and mucosal immune dysregulation. However, mechanisms by which gut microbiome contributes to the ADs and whether antioxidant treatment can restore gut homeostasis and ameliorate the disease outcome are not known. This study was, therefore, focused on examining the involvement of gut microbiome and host responses in the pathogenesis of SLE using unique female mouse models (C57BL/6, MRL+/+ and MRL/lpr) of 6 and 18 weeks with varying degrees of disease progression. Fecal microbiome diversity and composition, gut oxidative stress (OS), barrier function and inflammation, as well as systemic autoimmunity were determined. Interestingly, each mouse strain had distinct bacterial community as revealed by β-diversity. A lower Firmicutes/Bacteroidetes ratio in 6-week-old MRL/lpr mice was observed, evidenced by decrease in Peptostreptococcaceae under Firmicutes phylum along with enrichment of Rikenellaceae under Bacteroidetes phylum. Additionally, we observed increases in colonic OS [4-hydroxynonenal (HNE)-adducts and HNE-specific immune complexes], permeability changes (lower tight junction protein ZO-2; increased fecal albumin and IgA levels) and inflammatory responses (increased phos-NF-κB, IL-6 and IgG levels) in 18-week-old MRL/lpr mice. These changes were associated with markedly elevated AD markers (antinuclear and anti-smooth muscle antibodies) along with hepatic portal inflammation and severe glomerulonephritis. Notably, antioxidant N-acetylcysteine treatment influenced the microbial composition (decreased Rikenellaceae; increased Akkeransiaceae, Erysipelotrichaceae and Muribaculaceae) and attenuated the systemic autoimmunity in MRL/lpr mice. Our data thus show that gut microbiome dysbiosis is associated with increased colonic OS, barrier dysfunction, inflammatory responses and systemic autoimmunity markers. These findings apart from delineating a role for gut microbiome dysbiosis, also support the contribution of gut OS, permeability changes and inflammatory responses in the pathogenesis of ADs.

NK Cells in Autoimmune Diseases: Protective or Pathogenic?

Autoimmune diseases generally result from the loss of self-tolerance (i.e., failure of the immune system to distinguish self from non-self), and are characterized by autoantibody production and hyperactivation of T cells, which leads to damage of specific or multiple organs. Thus, autoimmune diseases can be classified as organ-specific or systemic. Genetic and environmental factors contribute to the development of autoimmunity. Recent studies have demonstrated the contribution of innate immunity to the onset of autoimmune diseases. Natural killer (NK) cells, which are key components of the innate immune system, have been implicated in the development of multiple autoimmune diseases such as systemic lupus erythematosus, type I diabetes mellitus, and autoimmune liver disease. However, NK cells have both protective and pathogenic roles in autoimmunity depending on the NK cell subset, microenvironment, and disease type or stage. In this work, we review the current knowledge of the varied roles of NK cell subsets in systemic and organic-specific autoimmune diseases and their clinical potential as therapeutic targets.

Sexual dimorphism in immunometabolism and autoimmunity: Impact on personalized medicine

Immune cells play essential roles in metabolic homeostasis and thus, undergo analogous changes in normal physiology (e.g., puberty and pregnancy) and in various metabolic and immune diseases. An essential component of this close relationship between the two is sex differences. Many autoimmune diseases, such as systemic lupus erythematous and multiple sclerosis, feature strikingly increased prevalence in females, whereas in contrast, infectious diseases, such as Ebola and Middle East Respiratory Syndrome, affect more men than women. Therefore, there are fundamental aspects of metabolic homeostasis and immune functions that are regulated differently in males and females. This can be observed in sex hormone-immune interaction where androgens, such as testosterone, have shown immunosuppressive effects whilst estrogen is on the opposite side of the spectrum with immunoenhancing facilitation of mechanisms. In addition, the two sexes exhibit significant differences in metabolic regulation, with estrous cycles in females known to induce variability in traits and more pronounced metabolic disease phenotype exhibited by males. It is likely that these differences underlie both the development of metabolic and autoimmune diseases and the response to current treatment options. Sexual dimorphism in immunometabolism has emerged to become an area of intense research, aiming to uncover sex-biased effector molecules in the various metabolic tissues and immune cell types, identify sex-biased cell-type-specific functions of common effector molecules, and understand whether the sex differences in metabolic and immune functions influence each other during autoimmune pathogenesis. In this review, we will summarize recent findings that address these critical questions of sexual dimorphism in immunometabolism as well as their translational implications for the clinical management of autoimmune diseases.

Case Report: Psychopathological Syndromes in the Course of Lupus Erythematosus and the Co-occurrence of Lupus Erythematous With Mental Disorders

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease that leads to a chronic inflammatory process in tissues and organs. The neuropsychiatric systemic lupus erythematosus (NPSLE) is a set of neuropsychiatric symptoms that derive from the central and peripheral nervous system and are observed in the course of SLE. Case Report and Final Diagnostic and Therapeutic Results: A diagnostic and therapeutic process in a patient with the signs and symptoms of SLE and bipolar disorder (BD) has been described. Bipolar disorder has been diagnosed as a primary disorder while SLE as a comorbid disease. Discussion: Common immunological mechanisms in BD and SLE are the reason for difficulties in diagnosing BD with co-occurring SLE. It should be determined whether BD is a primary disorder or a secondary component of a clinical picture of SLE (NPSLE) or whether mood and/or psychotic disorders are the result of steroid therapy in the course of SLE (steroid-induced mood and psychotic disorders, SIMPD). Conclusion and the Patient's Perspective: The presented case report is a unique description of a patient with a primary diagnosis of BD with comorbid SLE.

The triggering of post-COVID-19 autoimmunity phenomena could be associated with both transient immunosuppression and an inappropriate form of immune reconstitution in susceptible individuals

With the progression of the COVID-19 pandemic, there have been different reports about the development of autoimmune diseases once the infection is controlled. After entering the respiratory epithelial cells, SARS-CoV-2-the virus that causes the disease-triggers a severe inflammatory state in some patients known as "cytokine storm" and the development of thrombotic phenomena-both conditions being associated with high mortality. Patients additionally present severe lymphopenia and, in some cases, complement consumption and autoantibody development. There is a normalization of lymphocytes once the infection is controlled. After this, autoimmune conditions of unknown etiology may occur. A hypothesis for the development of post-COVID-19 autoimmunity is proposed based on the consequences of both a transient immunosuppression (both of innate and acquired immunity) in which self-tolerance is lost and an inappropriate form of immune reconstitution that amplifies the process.

Association between systemic lupus erythematosus and lung cancer: results from a pool of cohort studies and Mendelian randomization analysis

Background

Epidemiological evidence suggested that systemic lupus erythematosus (SLE) might be correlated with an increased risk of lung cancer. Nevertheless, few studies have comprehensively investigated their correlation and the causal effect remains unclear. With a meta-analysis and Mendelian randomization (MR) approach, we were able to systematically investigate the relationship between SLE and lung cancer risk.

Methods

A systematic search of cohort studies was conducted using network databases from the inception dates to February 1, 2020. Meta-analysis was performed to calculate standardized incidence rate (SIR) and their 95% CI. Furthermore, utilizing 33 SLE-related single nucleotide polymorphisms as instrumental variables (IVs) identified by the latest genome-wide association studies (GWASs), we investigated the correlation between genetically predisposed SLE and lung cancer risk using summary statistics from the International Lung Cancer Consortium (11,348 cases and 15,861 controls). The Inverse variance-weighted method was applied to estimate the causality and we further evaluated the pleiotropy by means of the weighted median and the MR-Egger regression method. Subgroup analysis according to different histotypes of lung cancer was also conducted.

Results

Through meta-analysis of 15 cohort studies involving 110,519 patients, we observed an increased risk of lung cancer among SLE patients (SIR =1.63, 95% CI, 1.39-1.90). Subgroup analysis suggested that female patients (SIR =1.28, 95% CI, 1.13-1.44) have a relatively higher lung cancer risk compared with male patients (SIR =1.15, 95% CI, 1.02-1.30). MR analysis indicated that genetically predisposed SLE was causally associated with an increased lung cancer risk (OR =1.045, 95% CI, 1.005-1.086, P=0.0276). When results were examined by histotypes, a causal relationship was observed between genetically predisposed SLE and squamous cell lung cancer (OR =1.065, 95% CI, 1.002-1.132, P=0.0429). Additionally, the results demonstrated the absence of the horizontal pleiotropy.

Conclusions

Both meta-analysis and MR analysis results suggested that SLE was associated with an increased lung cancer risk. Further investigations are warranted to investigate the etiology underlying the attribution of SLE to lung cancer.

Prevalence and incidence of systemic lupus erythematosus in Tucumán, Argentina

The aim of this study was to determine the prevalence and incidence of Systemic Lupus Erythematosus (SLE) in Tucumán, Argentina.

METHODS

The study included inpatient and outpatient charts from four public hospitals and private practice rheumatology clinics, all of them members of the Tucumán Rheumatology Society. Patients older than 16 years with diagnosis of SLE between January 2005 and December 2012 were included. Prevalence and annual incidence were calculated as the number of cases per 100.000 inhabitants during the period 2005 to 2012.

RESULTS

Three hundred fifty-three patients were identified. The mean age at diagnosis was 30.5 ± 11.7 years, 93.5% women, 83% mestizos. Prevalence was 24.3 cases/100.000 inhabitants (CI 95% 22.6-28.8) and age-adjusted (≥16 years) of 34.9 cases/100.000 inhabitants (CI 95% 32.8-41.1). The annual incidence in 2005 was 1.8 cases/100.000 inhabitants (95% CI 1-2.9) and 2012 of 4.2 cases/100.000 inhabitants (95% CI 2.9-5.8). Mortality was 9.1%, with infections being the most frequent cause (14/32).

CONCLUSION

The prevalence of SLE in the province of Tucumán was 34.9 cases/100.000 inhabitants.

Evidence of Renal Iron Accumulation in a Male Mouse Model of Lupus

Lupus nephritis represents a common and serious complication of the autoimmune disease Systemic Lupus Erythematosus (SLE). Clinical studies suggest that several proteins related to iron metabolism, including transferrin, serve as urinary biomarkers of lupus nephritis. We previously reported that in female NZBWF1 mice, a commonly used mouse model of SLE with a female sex bias, increased urinary transferrin excretion and renal iron accumulation occur around the onset of albuminuria. The current study investigated whether similar findings occur in male mice of a different mouse model of SLE, the MRL/lpr mouse. Two different cohorts were studied: MRL/lpr mice at an early, pre-albuminuric age (8 weeks), and after developing albuminuria (>100 mg/dL, confirmed by ELISA); age-matched MRL/MpJ control strain mice served for comparison. Urinary transferrin excretion was dramatically increased in the older, albuminuric MRL/lpr mice compared to the age-matched MRL/MpJ (P < 0.05), but there was no significant difference between strains at 8 weeks of age. Similarly, there were no significant differences between strains in renal cortical or outer medullary non-heme iron concentrations at 8 weeks. In the older, albuminuric MRL/lpr mice, renal cortical and outer medullary non-heme iron concentrations were significantly increased compared with age-matched MRL/MpJ mice, as was the expression of the iron storage protein ferritin (P < 0.01). Together, these data show that increased urinary transferrin excretion and renal tissue iron accumulation also occurs in albuminuric male MRL/lpr mice, suggesting that renal iron accumulation may be a feature of multiple mouse models of SLE.

The circRNA-miRNA-mRNA regulatory network in systemic lupus erythematosus

INTRODUCTION/OBJECTIVES

Systemic lupus erythematosus (SLE) was an autoimmune disease with a large variety of clinical manifestations and involving many organs. Its exact etiology was unclear, and studies had shown that T cells may play an important role. In this study, we wished to study the regulatory mechanism of circRNA in the T cells from SLE patients.

METHOD

GSE84655 was retrieved from the GEO database, and the corresponding probe name was converted into an international standard circRNA name by using the practical extraction and report language. The differentially expressed circRNAs (DECs) were analyzed by using R software. Subsequently, we used multiple bioinformatics methods to obtain the target miRNAs of circRNAs and the downstream mRNAs of miRNAs. Finally, a circRNA-miRNA-mRNA regulatory network was constructed and visualized by using Cytoscape 3.6.1 software.

RESULTS

There were a total of 29 DECs that had been identified, including 2 upregulated circRNAs and 27 downregulated circRNAs. After a lot of in-depth analysis, we finally obtained a circRNA-miRNA-mRNA regulatory network consisting of 8 DECs (hsa_circ_0006770, hsa_circ_0002904, hsa_circ_0034044, hsa_circ_0023685, hsa_circ_0049271, hsa_circ_0074491, hsa_circ_0074559, and hsa_circ_0023461), 4 overlap miRNAs (hsa-miR-326, hsa-miR-569, hsa-miR-638, and hsa-miR-1246), and 13 target mRNAs (EPHB3, USH1G,UBE4A, DCAF7, TBL1XR1, SLC27A4, SMO, NAA30, RSBN1, PLAG1, SOX2, GPATCH11, and DYRK1A).

CONCLUSIONS

This study could provide a novel insight into the role of circRNA and the circRNA-miRNA-mRNA regulation network in the SLE. However, it also needed to be verified by subsequent experiments and clinical studies. Key Points • There were 29 DECs (2 up and 27 down) between T cells of SLE and health control. • Hsa-miR-338-3p, hsa-miR-767-3p, and hsa-miR-1827 were the most frequent miRNAs. • We obtained a circRNA-miRNA-mRNA regulatory network for SLE.

Causality assessment of adverse events following immunization: the problem of multifactorial pathology

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to national vaccine injury compensation programs. If manufacturing defects or vaccine storage and delivering errors are excluded, the majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible "other causes" that can explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents some concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.

Causality assessment of adverse events following immunization: the problem of multifactorial pathology

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to vaccine injury compensation programs. The majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible "other causes" that might explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents several concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. Given these inadequacies in the evaluation of multifactorial diseases, the WHO guidelines need to be reevaluated and revised. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.