Vitamin D and systemic lupus erythematosus: continued evolution

What is known about the effects of vitamin D in neuropsychiatric lupus?

Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect several organs and systems. The central and/or peripheral nervous system can suffer from complications known as neuropsychiatric lupus (NPSLE). Studies have associated the manifestations of SLE or NPSLE with vitamin D deficiency. It has been shown that hypovitaminosis D can lead to cognition deficits and cerebral hypoperfusion in patients with NPSLE. In this review article, we will address the main features related to vitamin D supplementation or serum vitamin D levels with neuropsychiatric manifestations, either in patients or in animal models of NPSLE.

Vitamin D and Autoimmune Rheumatic Diseases

Vitamin D is a steroid hormone with potent immune-modulating properties. It has been shown to stimulate innate immunity and induce immune tolerance. Extensive research efforts have shown that vitamin D deficiency may be related to the development of autoimmune diseases. Vitamin D deficiency has been observed in patients with rheumatoid arthritis (RA) and has been shown to be inversely related to disease activity. Moreover, vitamin D deficiency may be implicated in the pathogenesis of the disease. Vitamin D deficiency has also been observed in patients with systemic lupus erythematosus (SLE). It has been found to be inversely related to disease activity and renal involvement. In addition, vitamin D receptor polymorphisms have been studied in SLE. Vitamin D levels have been studied in patients with Sjogren's syndrome, and vitamin D deficiency may be related to neuropathy and the development of lymphoma in the context of Sjogren's syndrome. Vitamin D deficiency has been observed in ankylosing spondylitis, psoriatic arthritis (PsA), and idiopathic inflammatory myopathies. Vitamin D deficiency has also been observed in systemic sclerosis. Vitamin D deficiency may be implicated in the pathogenesis of autoimmunity, and it may be administered to prevent autoimmune disease and reduce pain in the context of autoimmune rheumatic disorders.

Is Vitamin D Deficiency the Cause or the Effect of Systemic Lupus Erythematosus: Evidence from Bidirectional Mendelian Randomization Analysis

Background

Vitamin D deficiency is common in patients with systemic lupus erythematosus (SLE). Observational studies have reported that it is associated with SLE. In this bidirectional Mendelian randomization (MR) study, we explored the genetic association between serum vitamin D (VD) levels and SLE using two models.

Methods

Genetic variants associated with vitamin D (n = 304,181), 25-hydroxyvitamin D levels (n = 401,460), and SLE (n = 213,683) at genome-wide significance (P < 5∗10⁻⁸) derived from large-scale publicly available GWAS data were used as instrumental variables. Bidirectional two-sample MR analyses were performed using the inverse variance weighted method (IVW, random, or fixed effect model). Sensitivity analyses including maximum likelihood, MR-Egger method, penalized weighted median method, MR-PRESSO, MR-RAPS, and MR-radial method were conducted.

Results

The findings showed that genetically predicted SLE using the IVW method had a negative effect on the vitamin D and 25-hydroxyvitamin D levels in the two models. The results of sensitivity analyses of different analytical approaches were consistent.

Conclusions

These findings indicated that genetically determined SLE had a negative effect on the vitamin D and 25-hydroxyvitamin D levels. Future studies, including random controlled clinical trials, should evaluate the association and mechanisms between serum VD levels and SLE.

Life factors acting on systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a highly heterogeneous autoimmune disease that primarily affects women. Currently, in the search for the mechanisms of SLE pathogenesis, the association of lifestyle factors such as diet, cigarette smoking, ultraviolet radiation exposure, alcohol and caffeine-rich beverage consumption with SLE susceptibility has been systematically investigated. The cellular and molecular mechanisms mediating lifestyle effects on SLE occurrence, including interactions between genetic risk loci and environment, epigenetic changes, immune dysfunction, hyper-inflammatory response, and cytotoxicity, have been proposed. In the present review of the reports published in reputable peer-reviewed journals and government websites, we consider the current knowledge about the relationships between lifestyle factors and SLE incidence and outline directions of future research in this area. Formulation of practical measures with regard to the lifestyle in the future will benefit SLE patients and may provide potential therapy strategies.

Higher IgG level correlated with vitamin D receptor in the hippocampus of a pristane-induced lupus model

INTRODUCTION/OBJECTIVES

Patients with systemic lupus erythematosus (SLE) may have neurological complications, characterizing neuropsychiatric lupus (NPSLE). Studies have investigated alternative therapies such as vitamin D, which has an effect on the immune system and brain, to control manifestations of SLE. Experimental lupus models may be a good alternative to best study the immunological mechanisms underlying the development of NPSLE, and the animal model of pristane-induced lupus (PIL) may mimic SLE symptoms in humans. Our objective was to evaluate central nervous system involvement and vitamin D supplementation in a PIL model.

METHOD

Female BALB/c mice were divided into controls (CO; n = 7), PIL (n = 9), and PIL supplemented with vitamin D (VD; n = 7). The hippocampus area was measured and immunoassays were performed for detecting vitamin D receptor (VDR) and IgG.

RESULTS

The PIL group had a higher hippocampal IgG infiltrate when compared to the CO group. Vitamin D showed potential for reducing IgG infiltration. The hippocampus area was similar in all groups. No differences in VDR expression were observed between groups. A positive correlation was observed between the expression of VDR and IgG in the hippocampus.

CONCLUSION

Our data suggest that increased IgG infiltration into the hippocampus indicated an inflammatory process that may have stimulated VDR expression. Key Points • IgG infiltrate is higher in PIL animals than controls • VDR increases along with IgG infiltrate • Hippocampal VDR expression does not increase with vitamin D supplementation.

Prevalence of periapical abscesses in patients with systemic lupus erythematosus

AIMS

To assess the prevalence of periapical abscesses in patients with systemic lupus erythematosus (SLE), and to evaluate the effect of glucocorticoids (GCs) used to treat SLE, on the prevalence of such lesions.

METHODS

Integrated data of hospital patients was used. Data from the corresponding diagnosis codes for SLE and periapical abscess was retrieved by searching the appropriate query in the database. The odd ratio (OR) of periapical abscesses and its association with SLE and intake of GCs were calculated and analyzed statistically.

RESULTS

The prevalence of periapical abscesses in patients treated with GCs was 1.5% compared to 0.39% in patients who were not treated with GCs. The OR for periapical abscesses in patients treated with GCs was 2.53 compared with OR of 0.66 in patients not treated with GCs. The differences were statistically significant (p < .0001). The prevalence of periapical abscesses in patients with SLE was 1.88%. The OR was 3.18 and the difference statistically significant (p < .0001).

CONCLUSIONS

Under the conditions of this study, it appears that the prevalence of periapical abscesses is higher in patients with SLE. Patients receiving GCs therapy, either for SLE or for other conditions, may present higher prevalence of periapical abscesses.

Vitamin D in Colombian patients with systemic lupus erythematosus and its correlation with disease activity

Introduction

Patients with systemic lupus erythematosus (SLE) frequently present low levels of vitamin D. However, studies that have evaluated its association with disease activity have generated contradictory results.

Methods

A cross-sectional study was carried out on patients diagnosed with SLE in two hospitals in Manizales, Colombia. Disease activity was evaluated by the SLE disease activity index 2000 (SLEDAI-2K) and serum concentration of 25-hydroxyvitamin D (25(OH)D) was measured by chemiluminescence. The correlation analysis was accomplished with the Spearman correlation coefficient.

Results

The study included 51 patients. The median SLEDAI-2K score was 8 points. The mean serum level of 25(OH)D was 24.5 ng/ml. Of the participants, 37.3% had vitamin D insufficiency and 35.3% had deficiency. An inverse correlation was found between the levels of the 25(OH)D and the SLEDAI-2K score ( r = –0.578, p < 0.001), being greater in late-onset lupus, with absence of polyautoimmunity and in patients using glucocorticoids.

Conclusions

Low levels of vitamin D are frequent in SLE, presenting an inverse correlation with the disease activity. This is influenced by the use of glucocorticoids, the presence of late-onset lupus and the absence of polyautoimmunity.

Vitamin D in SLE: a role in pathogenesis and fatigue? A review of the literature

Fatigue is a common, disabling problem that is highly prevalent in patients with systemic lupus erythematous (SLE). More recently, vitamin D status has been established as a potential contributor to SLE pathogenesis and manifestations, in particular fatigue. This review summarizes the literature regarding the role of vitamin D in SLE, and provides an overview of the recent literature examining the association between vitamin D and fatigue in patients with SLE. Finally, the role of vitamin D supplementation in the treatment of SLE-related fatigue is considered.

Role of vitamin D deficiency in systemic lupus erythematosus incidence and aggravation

Vitamin D is one of the main groups of sterols; playing an important role in phospho-calcic metabolism. The conversion of 7-dehydrocholesterol to pre- vitamin D3 in the skin, through solar ultraviolet B radiation, is the main source of vitamin D. Since lupus patients are usually photosensitive, the risk of developing vitamin D deficiency in is high in this population. Although evidences showed the connotation between systemic lupus erythematosus (SLE) and vitamin D through which SLE can lead to lower vitamin D levels, it is also important to consider the possibility that vitamin D deficiency may have a causative role in SLE etiology. This paper analyzes existing data from various studies to highlight the role of vitamin D deficiency in SLE occurrence and aggravation and the probable efficacy of vitamin D supplementation on SLE patients. We searched “Science Direct” and “Pub Med” using “Vitamin D” and “SLE” for finding the studies focusing on the association between vitamin D deficiency and SLE incidence and consequences. Evidences show that vitamin D plays an important role in the pathogenesis and progression of SLE and vitamin D supplementation seems to ameliorate inflammatory and hemostatic markers; so, can improve clinical subsequent.

Altered microRNAs expression in T cells of patients with SLE involved in the lack of vitamin D

Vitamin D has been recognized as a potent immunomodulator and its deficiency is common in different population groups including patients with SLE. As miRNAs regulation plays a significant role in SLE, the present study aimed to evaluate the association between vitamin D status and miRNAs levels in patients with SLE. The serum concentrations of vitamin D (25-hydroxyvitamin D) and the levels of six miRNAs in T cells from patients with SLE were measured in 42 SLE cases and 48 healthy controls. Vitamin D treatment was also performed in isolated and cultured T cells from SLE patients in different times and doses. Vitamin D insufficiency (25-hydroxyvitamin D concentration <20 ng/ml) was more common in cases than in controls. Although age and BMI were similar, cases had significantly lower concentrations of miRNA-377, miRNA-342, miRNA-10a, miRNA-374b, miRNA-125a, and miRNA-410 than controls. Furthermore, a significant positive correlation was also observed between 25-hydroxyvitamin D concentrations and measured miRNAs levels. A significant difference in observed miRNAs levels was also observed in patients with 25-hydroxyvitamin D insufficiency compared with patients with 25-hydroxyvitamin D concentration ≥20 ng/ml. And 1α,25(OH)₂D₃ differentially regulated miRNAs expression in dose- and time- manner in vitro. Lower expressions of miRNA-377, miRNA-342, miRNA-10a, miRNA-374b, miRNA-125a, and miRNA-410 were found in SLE patients. And severe vitamin D deficiency is associated with decreased observed miRNAs levels in SLE patients. A 25-hydroxyvitamin D concentration value <20 ng/ml is suggested as the “cut-off” for such immunological alterations in patients with SLE.

Interferon alpha gene expression and serum level association with low vitamin D levels in Egyptian female patients with systemic lupus erythematosus

Background Patients with systemic lupus erythematosus (SLE) are prone to develop vitamin D (25(OH) D3) deficiency, due to several factors and there is an association between lower vitamin D levels and higher SLE disease activity. The aim of this research was to assess the prevalence of vitamin D deficiency in Egyptian female patients with SLE. Furthermore, we analyzed the potential relationship between this deficiency and SLE manifestations, disease activity, and its effect on interferon alpha (IFN-α) gene expression and serum level. Methods We evaluated the serum levels of vitamin D 25(OH)D3 and IFN-α by enzyme-linked immunosorbent assay (ELISA). IFN-α gene expression was measured by real-time polymerase chain reaction (PCR) assay in 123 Egyptian female patients with SLE and in 100 females as a healthy control group. Results Vitamin D deficiency was prevalent in 20.30%, while insufficiency was prevalent in 42.40% of the total group of patients. Serum levels of 25(OH)D3 were significantly decreased in the group of severe disease, and in the group of patients with lupus nephritis. 25(OH)D3 showed highly significant negative correlation with the SLE Disease Activity Index (SLEDAI) in the high activity group and lupus nephritis group. There was a significant negative correlation between 25(OH)D3 and IFN-α serum level and gene expression in all patients; more significant in the group with lupus nephritis. Conclusions The deficiency of 25(OH)D3 has a direct relationship with increase disease activity and nephritis in Egyptian SLE patients, suggesting the need for vitamin D supplementation in these patients. Also, it is directly correlated with increased secretion and gene expression of IFN-α, suggesting its role in pathogenesis of lupus nephritis, to be confirmed by further longitudinal observational studies.

Cytokines in systemic lupus erythematosus: far beyond Th1/Th2 dualism lupus: cytokine profiles

The aims of this study were to delineate cytokine profiles of systemic lupus erythematosus (SLE), construct prediction models for diagnosis and disease activity using those profiles, and to examine the associations between TNFB Ncol polymorphism, body mass index (BMI) and vitamin D levels with cytokine levels. Two hundred SLE patients and 196 healthy controls participated in this case-control study. Plasma cytokines levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-1β, IL- 4, IL-6, IL-10, IL-12 and IL-17 were measured and cytokines profiles were computed. IL-6, IL-12, IL-17, IFN-γ and IL-10 levels were significantly higher in SLE, while IL-4 was lower in SLE. The Th1/Th2 and Th1+Th17/Th2 profiles were significantly higher in SLE than in healthy controls, whereas there were no significant differences in the proinflammatory cytokine profile (TNFα+IL-6+IL-1β). In total, 90.4% of all subjects were correctly classified using Th1+Th17 profile and IL-10 (positively associated) and IL-4 (negatively associated) as predictor variables (sensitivity=66.7% and specificity=96.9%). In all, 20.9% of the variance in the SLE Disease Activity Index was predicted by the Th1+Th17/Th2 ratio, IL-10 and BMI (all positively) and proinflammatory profile (inversely associated). B1/B1 genotype is accompanied by increased IL-17 and Th17/Th2 ratio, while B1/B2 genotype is accompanied by higher IL-4 and IFNγ values. 25-OH vitamin D was inversely associated with IFN-γ levels. SLE is accompanied by Th1, Th17 and Treg profile and lowered IL-4 production. Lowered vitamin D levels and B1/B1 genotype, but not BMI, contribute to changes in cytokines profiles. Future treatments should target Th1, Th2 and Th17 profiles rather than inflammatory cytokines.

Systemic lupus erythematosus diagnosis and management

SLE presents many challenges for clinicians. The onset of disease may be insidious, with many different symptoms and signs, making early and accurate diagnosis challenging. Tests for SLE in the early stages lack specificity; those that are useful later often appear only after organ damage is manifest. Disease patterns are highly variable; flares are not predictable and not always associated with biomarkers. Children with SLE may have severe disease and present special management issues. Older SLE patients have complicating co-morbid conditions. Therapeutic interventions have improved over recent decades, but available drugs do not adequately control disease in many patients, and successful outcomes are limited by off-target effects; some of these become manifest with longer duration of treatment, now in part revealed by improved rates of survival. Despite all of these challenges, advances in understanding the biological basis of SLE have translated into more effective approaches to patient care. This review considers the current state of SLE diagnosis and management, with a focus on new approaches and anticipated advances.

An exploratory study into factors influencing development of acute canine polyradiculoneuritis in the UK

OBJECTIVES

To investigate whether the development of acute canine polyradiculoneuritis is associated with various putative risk factors.

MATERIALS AND METHODS

Retrospective case-control study with conditional logistic regression analysis from a referral hospital population in the UK where controls were matched for year of presentation.

RESULTS

Forty-three cases were identified with acute canine polyradiculoneuritis and 86 controls were selected. Jack Russell terriers and West Highland white terriers were found to have a significantly greater odds of developing acute canine polyradiculoneuritis compared to a mixed baseline group of dogs. The odds of developing acute canine polyradiculoneuritis were greater in the autumn and winter compared to spring. Vaccination, rural/urban habitation, sex, neuter status and age were not associated with development of acute canine polyradiculoneuritis in our population of dogs.

CLINICAL SIGNIFICANCE

Breed and season were associated with development of acute canine polyradiculoneuritis. However, this is a small sample and so this observation needs confirmation in further studies and other factors may also be involved. Nevertheless, these findings may be important in further understanding the aetiopathogenesis of this condition.

The effect of Vitamin D supplementation in disease activity of systemic lupus erythematosus patients with Vitamin D deficiency: A randomized clinical trial

Background:

The aim of this study was to check the effectiveness of Vitamin D supplementation on the disease activity of Vitamin D-deficient systemic lupus erythematosus (SLE) patients.

Materials and Methods:

In this randomized, double-blind, placebo-controlled trial, 45 Vitamin D-deficient SLE patients were studied in two groups, namely interventional and placebo groups. The interventional group patients were treated with Vitamin D (50,000 unit/weekly Vitamin D for 12 weeks and then 50,000 unit/monthly for 3 months) and placebo group patients were only administered the placebo. The level of Vitamin D and the level of disease activity using SLE disease activity index (SLEDAI) were measured before and after intervention period in each group, and for intra- and between-groups comparison, we used t-test and repeated measure ANOVA.

Results:

A total of 90 patients were enrolled in this study. The mean of Vitamin D was increased significantly after therapy in interventional group (17.36 ± 4.26 ng/ml vs. 37.69 ± 5.92 ng/ml, P < 0.001). The mean of Vitamin D had no significant difference before and after intervention in placebo group (16.78 ± 4.39 ng/ml vs. 16.62 ± 4.61 ng/ml, P = 0.53). The mean of disease activity (SLEDAI) was not different significantly before and after Vitamin D administration in interventional group (3.09 vs. 1.62 ± 1.25, P = 0.39). The mean of disease activity (SLEDAI) was not different significantly before and after intervention in placebo group (3.09 vs. 1.98 ± 2.47, P = 0.42).

Conclusion:

According to our study, it is suggested that using Vitamin D in patients with SLE could not have better outcomes in this regard. However, there are many unknown environmental or biological factors which are associated with the disease activity of SLE and have not been identified yet.

Vitamin D Level Between Calcium-Phosphorus Homeostasis and Immune System: New Perspective in Osteoporosis

Vitamin D is a key molecule in calcium and phosphate homeostasis; however, increasing evidence has recently shown that it also plays a crucial role in the immune system, both innate and adaptive. A deregulation of vitamin D levels, due also to mutations and polymorphisms in the genes of the vitamin D pathway, determines severe alterations in the homeostasis of the organism, resulting in a higher risk of onset of some diseases, including osteoporosis. This review gives an overview of the influence of vitamin D levels on the pathogenesis of osteoporosis, between bone homeostasis and immune system.

Eppur Si Muove: vitamin D is essential in preventing and modulating SLE

Systemic lupus erythematosus (abbreviated SLE or lupus) is a systemic autoimmune disease, with genetic, immunologic, hormonal, and environmental factors. 1 One of the environmental factors that has been studied over the years is vitamin D, which is created in the human body in response to exposure to sunlight and ultraviolet (UV) radiation.

This review aims at examining findings from recent years, specifically 2013–2014, regarding the relationship between vitamin D deficiency and SLE flares, severity, and clinical manifestation, as well as to examine the treatment options derived from this relationship.

Serum Vitamin D Level is Inversely Associated With Anti-Cyclic Citrullinated Peptide Antibody Level and Disease Activity in Rheumatoid Arthritis Patients

Objectives

This study aims to assess the relationship between serum vitamin D and anti-cyclic citrullinated peptide (anti-CCP) antibody levels, as well as disease activity in patients with newly diagnosed rheumatoid arthritis (RA).

Patients and methods

These measurements were conducted between January 2014 and June 2014. Serum 25-hydroxy vitamin D (25-OH-D), anti- CCP antibody, and erythrocyte sedimentation rates were measured in a cohort of 154 patients (66 males, 88 females; mean age 53.5±12.4; range 29 to 79 years) with early RA. A control group of 60 healthy participants (25 males, 35 females; mean age 51.4±10.3; range 25 to 75 years) was only evaluated for serum 25-OH-D levels. Disease activity was measured by calculating the 28-Joint Disease Activity Score. Blood samples were drawn from cubital veins. After centrifugation, serum was collected and stored under minus 20 degrees.

Results

Vitamin D deficiency was more prevalent in RA group compared with control group (48.70% vs. 30.00%, p<0.05). Serum 25-OH-D levels were lower in RA group (19.46±8.20 ng/mL) than control group (23.18±6.71 ng/mL) (p<0.05). In the RA group, serum 25-OH-D levels were negatively correlated to anti-CCP antibody levels (rs= -0.360, p<0.001), erythrocyte sedimentation rate (rs= -0.270, p<0.001), age of patients (rs= -0.602, p<0.001), and disease activity (rs= -0.249, p<0.05), respectively. Serum 25-OH-D level did not vary according to sex in the RA group. In control group, females had lower serum 25-OH-D level (p=0.001, rs=0.404). In addition, serum 25-OH-D level was also negatively associated with age in control group (p<0.001, rs= -0.578). There were no differences between RA group and control group in terms of age and sex ratio.

Conclusion

Serum 25-OH-D level was negatively correlated to anti-CCP antibody level and disease activity, which implied the therapeutic role of serum 25-OH-D in RA.

25-Hydroxyvitamin D3 Deficiency Independently Predicts Cognitive Impairment in Patients with Systemic Lupus Erythematosus

OBJECTIVES

Cognitive dysfunction has been reported in 20-80% of SLE patients. Converging evidence has indicated the importance of vitamin D as a neuroimmunomodulator for cognitive function. In this study, we evaluated the relationship between vitamin D and cognitive dysfunction.

METHODS

Consecutive age- and gender-matched SLE patients and healthy controls (HCs) were administered Automated Neuropsychological Assessment Metrics in this cross-sectional study. The primary outcome was the total throughput score (TTS). Anxiety and depression were measured using the Hospital Anxiety and Depression Scale (HADS). Levels of 25-hydroxyvitamin D [25(OH)D3 and total 25(OH)D] were measured using Liquid Chromatography-Tandem Mass Spectrometry.

RESULTS

In total, 61 SLE patients and 61 HCs were studied. SLE patients scored significantly lower than HCs in the TTS (p = 0.004). There were no statistically significant differences in 25(OH)D3 levels, total 25(OH)D levels and total 25(OH)D deficiency between SLE patients and HCs. However, more SLE patients had 25(OH)D3 deficiency compared to HCs [12 (19.7%) versus 2 (3.3%), p = 0.003]. Deficiency of 25(OH)D3 (β = -63.667, SE = 27.456, p = 0.025), but not other vitamin D variables, independently predicted worse TTS after adjusting for age, education, gender, ethnicity, HADS-Total, duration of SLE, SELENA-SLEDAI, SLICC/ACR Damage Index and cumulative steroid dose in SLE patients. Age (β = -4.261, SE = 0.866, p < 0.001) was the only predictor of TTS after adjusting for education, gender, ethnicity, HADS-Total, vitamin D levels or status in HCs.

CONCLUSIONS

Deficiency of 25(OH)D3, a potentially modifiable risk factor, independently predicted cognitive impairment in SLE patients.

Seasonal Variation in Flares of Intestinal Behçet's Disease

BACKGROUND

There have been numerous investigations into the seasonality of several autoimmune diseases and inflammatory bowel disease in an effort to better understand the epidemiology and pathogenesis of these conditions. However, the relationship between the season and disease activity of intestinal Behçet's disease has not been investigated.

AIMS

This study aimed to evaluate the seasonal pattern of exacerbations of intestinal Behçet's disease.

METHODS

We evaluated 268 consecutive patients with intestinal Behçet's disease who were diagnosed and treated between November 1990 and March 2010 at Severance Hospital, Yonsei University, Seoul, Korea. Patient demographics, onset of symptoms, total number of relapses, and the month of each relapse were recorded. The relationship between the season and flares of intestinal Behçet's disease was analyzed.

RESULTS

A total of 339 relapses occurred in 142 patients (53 %). The median age at diagnosis was 39 (10-73) years; the median follow-up duration was 74 (7-372) months. The peak seasons for relapse were spring and autumn, especially the months of May and September (p value <0.001). Compared with winter, spring and autumn had higher rates of flares (HR 1.92 and 1.91, respectively, p value <0.001).

CONCLUSIONS

In this study, intestinal Behçet's disease demonstrated a biphasic pattern (peaks in spring and autumn) in exacerbations of disease, suggesting that seasonal or exogenous factors may be involved in the flares of intestinal Behçet's disease.

Rheumatologic Skin Disease

In common rheumatologic diseases skin findings are an important diagnostic clue for astute clinicians. Skin manifestations can help identify systemic disease or may require therapy uniquely targeted at the cutaneous problem. This article discusses 3 common rheumatologic conditions seen in adults by dermatologists: cutaneous lupus, dermatomyositis, and morphea. The focus is on the cutaneous findings and clinical presentation. Some approaches to treatment are explored. Clues to help identify systemic disease are also highlighted.

Immune Response Modulation by Vitamin D: Role in Systemic Lupus Erythematosus

Vitamin D plays key roles as a natural immune modulator and has been implicated in the pathophysiology of autoimmune diseases, including systemic lupus erythematosus (SLE). This review presents a summary and analysis of the recent literature regarding immunoregulatory effects of vitamin D as well as its importance in SLE development, clinical severity, and possible effects of supplementation in disease treatment.