Prevalence and sociodemographic correlates of antinuclear antibodies in the United States

Antinuclear antibody prevalence in a general pediatric cohort from Mexico City: discordance between immunofluorescence and multiplex assays

OBJECTIVE

To characterize antinuclear antibody (ANA) prevalence according to distinct assay methodologies in a pediatric cohort from Mexico City, and to further examine associations with age and sex.

METHODS

Serum ANA were measured by indirect immunofluorescence assay (IFA) and multiplex immunoassay in 114 children aged 9-17 years. IFA was considered positive at a cutoff titer of ≥1:80. Agreement between assay methods was assessed by kappa statistic. Sensitivity, specificity, and 95% confidence intervals (CIs) of the multiplex were computed with IFA as the reference standard.

RESULTS

Of the 114 children (mean age 14.7 [standard deviation 2.1] years; 54 [47%] female), 18 of 114 (15.8%) were ANA positive by IFA, and 11 of 114 (9.6%) by 11-antigen multiplex assay. ANA prevalence was higher in females compared with males by both of the methods (ratios 1.6-1.9 to 1). Agreement between tests was classified as slight by kappa (κ=0.177 [95% CI -0.051, 0.406]). The multiplex immunoassay had sensitivity of 22.2% (95% CI 6.4, 47.6) and specificity of 92.7% (95% CI 85.6, 97.0), and failed to capture 3 of 4 (75%) of the high-titer (≥1:1280) IFA-positives.

CONCLUSION

Up to 15% of children in this general population cohort were ANA positive, with a higher rate of positivity among females according to both assay methods. Substantial discordance in ANA results was found between IFA and multiplex methods, even for high-titer IFA positives. These findings underscore the need to sufficiently account for assay characteristics when interpreting ANA test results, and support IFA as the more appropriate assay for studies of subclinical autoimmunity.

The occurrence of autoantibodies in patients with chronic HCV infection, including patients dialyzed and after kidney transplantation

Introduction

There are reports suggesting that hepatitis C virus (HCV) may stimulate the autoimmune process. Studies have been undertaken to evaluate the occurrence and type of autoantibodies in HCV-infected patients with and without immunosuppression. Results were analyzed according to HCV genotype, intensity of inflammation and liver fibrosis stage.

Material and methods

The study included 105 patients chronically infected with HCV, including 25 with immunological suppression administered for kidney disease or kidney transplantation. Blood samples were tested by immunoblotting for the presence of AMA-M2, SLA/LP, LKM-1, LC1, anti-F-actin, anti-desmin, anti-myosin, anti-gp210 and anti-sp100 autoantibodies, and ANA. All the patients were scored for autoimmune hepatitis.

Results

Autoantibodies were detected in 32.5% of patients without immunosuppression and in 16% with immunosuppression. Single types of autoantibodies were identified in 26% of patients. The most frequent ones were ANA (19%) and AMA-M2 (5.7%). The presence of antibodies in patients with genotype 1 was significantly higher in comparison to their occurrence in genotype 3. Autoimmune hepatitis was not diagnosed in any of the patients. Immunoglobulin G level was significantly higher in patients with detectable autoantibodies, compared to patients without antibodies (1.89 vs. 1.28 g/dl, p < 0.001). No correlation between fibrosis stage or intensity of inflammatory state and the frequency of antibodies was found.

Conclusions

The antibodies are significantly more frequent in patients without immunosuppression and in patients infected with genotype 1 than genotype 3. The presence of these autoantibodies is not associated with the development of autoimmune hepatitis. Higher level of immunoglobulin G in the serum correlates with the presence of autoantibodies.

Anti-rods/rings autoantibody seropositivity does not affect response to telaprevir treatment for chronic hepatitis C infection

PURPOSE

Autoantibodies to intracellular 'rods and rings' structures (anti-rods/rings or anti-RR) are strongly associated with hepatitis C (HCV) patients treated with interferon-α/ribavirin (IFN/RBV) and are linked with non-responsiveness to IFN/RBV or relapse, especially in Italian patients. This is the first study to determine whether there is any correlation of anti-RR with non-responsiveness to IFN/RBV treatment in patients also treated with telaprevir (TPV), one of several new therapies for chronic HCV recently implemented.

METHODS

From 2013 to 2014, 52 HCV-infected patients were treated with IFN/RBV and TPV at five Italian clinics. Patient sera were collected and analyzed by indirect immunofluorescence for the presence of anti-RR antibodies. Patients were classified as anti-RR positive or anti-RR negative, and then various biological and clinical variables were analyzed to compare the two groups, including gender, age, HCV genotype, previous IFN/RBV treatment, and IFN/RBV/TPV treatment outcome.

RESULTS

Of these 52 HCV patients treated with IFN/RBV/TPV, 10/32 (31%) who previously received IFN/RBV were anti-RR positive, compared to 0 of 20 treatment-naïve patients. Anti-RR-positive patients relapsed more than anti-RR-negative patients (3/10, 30% vs. 2/42, 5%; p < 0.05). However, zero anti-RR-positive patients were non-responsive, and frequencies of sustained virological response were similar (anti-RR positive: 7/10, 70% vs. anti-RR negative: 33/42, 79%).

CONCLUSIONS

Overall, the data suggest that anti-RR seropositivity is not associated with resistance to TPV treatment in this patient cohort, but monitoring anti-RR-positive patients for relapse within the first 6 months after treatment may be useful.

Altered type II interferon precedes autoantibody accrual and elevated type I interferon activity prior to systemic lupus erythematosus classification

OBJECTIVES

The relationship of immune dysregulation and autoantibody production that may contribute to systemic lupus erythematosus (SLE) pathogenesis is unknown. This study evaluates the individual and combined contributions of autoantibodies, type I interferon (IFN-α) activity, and IFN-associated soluble mediators to disease development leading to SLE.

METHODS

Serial serum specimens from 55 individuals collected prior to SLE classification (average timespan=4.3 years) and unaffected healthy controls matched by age (±5 years), gender, race and time of sample procurement were obtained from the Department of Defense Serum Repository. Levels of serum IFN-α activity, IFN-associated mediators and autoantibodies were evaluated and temporal relationships assessed by growth curve modelling, path analysis, analysis of covariance and random forest models.

RESULTS

In cases, but not matched controls, autoantibody specificities and IFN-associated mediators accumulated over a period of years, plateauing near the time of disease classification (p<0.001). Autoantibody positivity coincided with or followed type II IFN dysregulation, preceding IFN-α activity in growth curve models, with elevated IFN-α activity and B-lymphocyte stimulator levels occurring shortly before SLE classification (p≤0.005). Cases were distinguished by multivariate random forest models incorporating IFN-γ, macrophage chemoattractant protein (MCP)-3, anti-chromatin and anti-spliceosome antibodies (accuracy 93% >4 years pre-classification; 97% within 2 years of SLE classification).

CONCLUSIONS

Years before SLE classification, enhancement of the type II IFN pathway allows for accumulation of autoantibodies and subsequent elevations in IFN-α activity immediately preceding SLE classification. Perturbations in select immunological processes may help identify at-risk individuals for further clinical evaluation or participation in prospective intervention trials.

The Avise Lupus Test and Cell-bound Complement Activation Products Aid the Diagnosis of Systemic Lupus Erythematosus

Background:

Systemic lupus erythematosus (SLE) is a multifaceted disease, and its diagnosis may be challenging. A blood test for the diagnosis of SLE, the Avise Lupus test, has been recently commercialized and validated in clinical studies.

Objectives:

To evaluate the use of the Avise Lupus test by community rheumatologists.

Methods:

The study is a longitudinal, case-control, retrospective review of medical charts. Cases had a positive test result, and controls had a negative result; all patients were anti-nuclear antibodies (ANA) positive but negative for SLE-specific autoantibodies. Features of SLE, diagnosis, and medications at two time points were recorded.

Results:

Twenty of the 23 cases (87%) and 4 of the 23 controls (17%) were diagnosed with SLE (sensitivity=83%; specificity=86%). More cases than controls (43% vs. 17%) fulfilled 4 American College of Rheumatology (ACR) classification criteria of SLE. Sensitivity of the test was significantly higher than the ACR score (83% vs. 42%, p=0.006). A higher percentage of patients who met the classification criteria had elevated cell-bound complement activation products (CB-CAPs) compared to patients who did not. Anti-rheumatic medications were used in a higher percentage of cases than controls (83% vs. 35% at baseline, p=0.002), suggesting that cases were treated more aggressively early on.

Conclusion:

A positive Avise Lupus test result aids in formulating a SLE diagnosis when diagnosis based on standard-of-care tests and clinical features may be challenging, and impacts patient management. Prospective studies will be performed to better evaluate the clinical utility of the test and of CB-CAPs as biomarkers of SLE.

Laboratory Evaluation of Vocal Fold Paralysis and Paresis

OBJECTIVES

This study aimed to assess the value of comprehensive laboratory evaluation in patients with vocal fold paralysis or paresis.

STUDY DESIGN

This is a retrospective chart review.

METHODS

Records of 231 patients with vocal fold paralysis or paresis were reviewed to determine whether there is a significant increase in the number of abnormal test results compared with rates of abnormal results for these tests in the general population and whether testing resulted in clinically important diagnosis. Laboratory data were collected from charts from initial visits from 2010 to 2014 and compared with national data.

RESULTS

When controlled for age and sex, white blood cell count was found to have a significantly higher rate of abnormal test results (P < 0.001) in patients with vocal fold paralysis or paresis than the general population. Although hemoglobin, thyroid-stimulating hormone, and thyroid antibody tests were more likely to be abnormal in our patient population, the trend was not statistically significant. Further, the prevalence of syphilis and myasthenia gravis was found to be higher in these subjects than their respective national prevalences, and the incidence of Lyme disease was found to be higher than the national prevalence of Lyme disease. Several patients were diagnosed with medically important conditions such as diabetes, thyroid dysfunction, syphilis, myasthenia gravis, and Lyme disease based on these tests.

CONCLUSION

This study suggests that comprehensive testing of patients with vocal fold movement disorders results in diagnoses that would be missed without a comprehensive evaluation, some of which are important medically, although their causal relationship to vocal fold paralysis or paresis was not investigated or established.

Differential capacity of therapeutic drugs to induce Rods/Rings structures in vitro and in vivo and generation of anti-Rods/Rings autoantibodies

Some HCV patients using ribavirin and interferon alpha (IFN-α) develop anti-rods and rings (RR) autoantibodies, the main target of which is inosine monophosphate dehydrogenase (IMPDH), the rate-determining enzyme in de novo GTP biosynthesis. In vitro inhibition of IMPDH by ribavirin induces RR formation. Here we investigate whether other commonly used drugs that interfere with GTP biosynthesis can induce RR structures in vitro and vivo and elicit generation of autoantibodies. HEp-2 cells treated for 24h with ribavirin, mycophenolic acid (MPA), azathioprine, methotrexate or acyclovir were positive for RR structures. However, adefovir, entecavir, tenofovir and lamivudine did not induce RR structures in these cells. Structures induced by ribavirin in HEp-2 cells are stable after 24h drug-washout, while structures induced by other drugs are relatively labile, disappearing within 2h. Looking at patients treated with these drugs, HCV patients treated with ribavirin (n=17) showed higher average percentage of RR-positive peripheral mononuclear cells than autoimmune patients treated with RR-inducing immunosuppressant drugs (n=21). Serum from 173 autoimmune patients who had been treated with MPA, azathioprine or methotrexate was tested for presence of anti-RR autoantibodies, and only one sample was found to be positive. Conversely, of 48 anti-RR autoantibody positive samples identified at Fleury Laboratories over 30months, 94% were from HCV patients treated with ribavirin plus IFN-α. These data indicate that RR structures can be induced by a variety of drugs in vitro and in vivo, but anti-RR autoantibody production is mostly restricted to HCV patients under ribavirin+IFN-α treatment.

Diagnostic value of blood tests for occult causes of initially idiopathic small-fiber polyneuropathy

Small-fiber polyneuropathy (SFPN) causes non-specific symptoms including chronic pain, cardiovascular, gastrointestinal, and sweating complaints. Diagnosis is made from history and exam in patients with known risk factors such as diabetes, but objective test confirmation is recommended for patients without known risks. If tests confirm SFPN, and it is "initially idiopathic" (iiSFPN), screening for occult causes is indicated. This study's aim was to evaluate the 21 widely available, recommended blood tests to identify the most cost-effective ones and to learn about occult causes of iiSFPN. Records were reviewed from all 213 patients with SFPN confirmed by distal-leg skin biopsy, nerve biopsy, or autonomic-function testing in our academic center during 2013. We determined the prevalence of each abnormal blood-test result (ABTR) in the iiSFPN cohort, compared this to population averages, and measured the costs of screening subjects to obtain one ABTR. Participants were 70 % female and aged 43.0 ± 18.6 years. High erythrocyte sedimentation rate (ESR) and antinuclear antibody (ANA; ≥1:160 titer) were most common, each present in 28 % of subjects. The ABTR ≥3 × more prevalent in iiSFPN than in the total population were high ESR, high ANA, low C3, and Sjögren's and celiac autoantibodies. Together, these suggest the possibility of a specific association between iiSFPN and dysimmunity. ABTR identifying diabetes, prediabetes, and hypertriglyceridemia were less common in iiSFPN than in the population and thus were not associated with iiSFPN here. The six most cost-effective iiSFPN-associated blood tests-ESR, ANA, C3, autoantibodies for Sjögren's and celiac, plus thyroid-stimulating hormone-had estimated cost of $99.57/person and 45.6 % probability of obtaining one abnormal result. Angiotensin-converting enzyme was elevated in 45 %, but no patients had sarcoidosis, so this test was futile here.

Prevalence and clinical significance of nonorgan specific antibodies in patients with autoimmune thyroiditis as predictor markers for rheumatic diseases

Autoimmune diseases are considered the 3rd leading cause of morbidity and mortality in the industrialized countries. Autoimmune thyroid diseases (ATDs) are associated with high prevalence of nonorgan-specific autoantibodies, such as antinuclear antibodies (ANA), antidouble-stranded deoxyribonucleic acid (anti-dsDNA), antiextractable-nuclear antigens (anti-ENAs), rheumatoid factor (RF), and anticyclic-citrullinated peptides (anti-CCP) whose clinical significance is unknown.We aimed to assess the prevalence of various nonorgan-specific autoantibodies in patients with ATD, and to investigate the possible association between these autoantibodies and occurrence of rheumatic diseases and, if these autoantibodies could be considered as predictor markers for autoimmune rheumatic diseases in the future.This study had 2 phases: phase 1; in which 61 ATD patients free from rheumatic manifestations were assessed for the presence of these nonorgan-specific autoantibodies against healthy 61 control group, followed by 2nd phase longitudinal clinical follow-up in which cases are monitored systematically to establish occurrence and progression of any rheumatic disease in association to these autoantibodies with its influences and prognosis.Regarding ATD patients, ANA, anti-dsDNA, Anti-ENA, and RF were present in a percentage of (50.8%), (18%), (21.3%), and (34.4%), respectively, with statistically significance difference (P < 0.5) rather than controls. Nearly one third of the studied group (32.8%) developed the rheumatic diseases, over 2 years follow-up. It was obvious that those with positive anti-dsDNA had higher risk (2.45 times) to develop rheumatic diseases than those without. There was a statistically significant positive linear relationship between occurrence of disease in months and (age, anti-dsDNA, anti-CCP, RF, and duration of thyroiditis). Anti-dsDNA and RF are the most significant predictors (P < 0.0001).ATD is more associated with rheumatic diseases than previously thought. Anti-dsDNA, RF, and anti-CCP antibodies may be used as predictive screening markers of systemic lupus erythematosus and RA, with early referral to rheumatologists for close follow-up and early diagnoses for appropriate disease management of the disease, as early disease control will allow better quality of life.

Association between Vitamin D Deficiency and Antinuclear Antibodies in Middle-Aged and Older U.S. Adults

BACKGROUND

Vitamin D deficiency is associated with cancer and autoimmune diseases, but little is known about the association between vitamin D and antinuclear antibodies (ANA), a biomarker of immune dysfunction in healthy populations. The objective of this study was to determine whether vitamin D deficiency is associated with ANA in middle-aged and older U.S. adults.

METHODS

A cross-sectional analysis using the National Health and Nutrition Examination Survey (NHANES) 2001-2004 was conducted. Data were available for 1,012 adults aged 50 years and older. Serum 25-hydroxyvitamin D levels were measured by radioimmunoassay. ANA was measured in a 1:80 dilution of sera by immunofluorescence using HEp-2 cells (seropositive = 3 or 4+).

RESULTS

Greater vitamin D deficiency was associated with higher ANA prevalence in the unadjusted (P_trend = 0.0002) logistic regression model and after adjustment for sex, age, education, race/ethnicity, season, and NHANES cycle (P_trend = 0.04). After adjustment, those with severe vitamin D deficiency (<10 ng/mL) had 2.99 (95% CI, 1.25-7.15) times the odds of ANA compared with having normal vitamin D levels (≥30 ng/mL), while deficient and insufficient individuals had twice the odds of ANA.

CONCLUSIONS

Among U.S. residents ages 50 and older, vitamin D deficiency was associated with higher prevalence of ANA. Vitamin D sufficiency may be important for preventing immune dysfunction in older populations.

IMPACT

Our findings support the growing evidence that vitamin D is an important immune modulator. Vitamin D deficiency in older adults may increase vulnerability to cancer by contributing to immune dysfunction. Cancer Epidemiol Biomarkers Prev; 25(12); 1559-63. ©2016 AACR.

Increasing incidence of elderly-onset autoimmune hepatitis

AIM

Autoimmune hepatitis (AIH) commonly shows bimodal distribution of onset age: at young adulthood and at 50-60 years-of-age. However, in recent times, the incidence of elderly-onset AIH seems to be increasing. This study aimed to investigate whether the incidence of elderly-onset AIH is increasing, and whether these patients show any clinical features different from those observed in younger patients.

METHODS

Data about patients with newly diagnosed AIH visiting the Japanese Red Cross Society Himeji Hospital, Himeji, Hyogo, Japan, were retrospectively collected for the period ranging from January 2010 to May 2016. A total of 71 patients (56 women and 15 men, age 18-88 years) were included in this study. Patients were divided into two cohorts: elderly (≥70 years; n = 28) and adult cohort (15-69 years; n = 43). Demographic and clinical characteristics, biochemical and serological markers, radiological and histological findings, and therapeutic courses were evaluated.

RESULTS

The median age of the patients was 65 years, the most frequent range being the 70s (37%), followed by the 60s (25%). The elderly cohort had significantly higher levels of serum immunoglobulin G and antinuclear antibody, lesser hepatitis activity scores, and lesser chance of developing other autoimmune diseases. They tended to have higher C-reactive protein levels and lower serum alanine aminotransferase levels. All patients achieved clinical remission after treatment.

CONCLUSIONS

This study clearly showed an increase in the incidence of elderly-onset AIH. These patients had some unique characteristics, showing that the development of elderly-onset AIH is influenced by age-associated immune dysfunction called immunosenescence. Geriatr Gerontol Int 2017; 17: 1722-1728.

Laboratory testing for the diagnosis, evaluation, and management of systemic lupus erythematosus: Still more questions for the next generations: A Tribute and Thanks and in Memory of my mentor: Henry G. Kunkel

This paper is a review, personal memoir, a tribute to Henry Kunkel, and a critique regarding laboratory tests used for the evaluation, diagnosis, and understanding Autoimmune Rheumatic Diseases, in particular systemic lupus erythematosus (SLE).

Prevalence of antinuclear antibodies in healthy Lebanese subjects, 2008-2015: a cross-sectional study involving 10,814 subjects

Antinuclear antibodies (ANA) are found at varying frequencies in healthy populations, depending on geographical location and ethnic background of participants. The main objective of this study was to determine the prevalence of ANA in healthy Lebanese population in the period 2008-2015. Study subjects comprised 10,851 individuals (3311 males and 7503 females). ANA positivity was determined using immunofluorescence on HEp-2 cells. The prevalence of positive ANA test at a titer of ≥1:100 was 26.4 %, with 696 individuals (6.4 %) having titers exceeding 1:100. Most ANA-positive cases were recorded between 2013 and 2015, which reflected increased assay sensitivity. ANA positivity was associated with increased age and with female gender. Significant increases in ANA positivity were seen with advanced age, with steady increases from the 30- to 40-year age group through the >70-year age group, with significantly higher prevalence noted in female participants. There was a steady and significant reduction in the number of ANA-positive cases with higher ANA titers, which ranged from 20.0 % (1/100) to 3.7 % (1/320), 1.7 % (1/640), and 1.1 % (1/1000). While 45 % of low ANA titer was seen in 31-60-year age category, compared with 19.8 % for 61+ year category, the distribution of high ANA titer was more uniform between 31+ year age categories, which ranged from 11.4 % (31-40 years) to 12.4 % (>70 years). This was consistently and significantly higher in female participants. The prevalence and distribution of ANA among Lebanese individuals were comparable to the rates established for Western countries and confirm the contribution of female gender and advanced age to ANA positivity.

Preclinical lupus

PURPOSE OF REVIEW

Systemic lupus erythematosus (SLE) is often preceded by immune dysregulation and clinical manifestations below the threshold for SLE classification. This review discusses current and evolving concepts about the preclassification period of SLE, including clinical and mechanistic observations, and potential avenues for early identification and intervention.

RECENT FINDINGS

Although incomplete lupus erythematosus (ILE) involves fewer clinical manifestations than SLE, ILE patients can suffer organ damage and early mortality. Common clinical features in ILE include antinuclear antibody seropositivity, polyarthritis, immunologic manifestations, and hematological disorders. Despite having lower disease activity and damage scores than SLE patients, ILE patients may develop pulmonary arterial hypertension, or renal, neurological, or peripheral vascular damage. The recently proposed Systemic Lupus International Collaborating Clinics SLE classification criteria could shift the period considered 'preclinical SLE'. Murine studies suggest that the balance of T-helper/T-regulatory cells, peroxisome proliferator-activated receptor γ activity, and plasmacytoid dendritic cell pathways may be valuable targets for early intervention.

SUMMARY

Advances in our understanding of early SLE, including stages before clinical features are fully developed, will improve our ability to identify individuals at high risk of classification for potential prevention trials, provide necessary information to improve diagnostic testing, and perhaps identify novel targets for directed therapeutics in clinical SLE.

Severity of dry eye syndrome is related to anti-dsDNA autoantibody in systemic lupus erythematosus patients without secondary Sjogren syndrome: A cross-sectional analysis

There are as many as one-third of the systemic lupus erythematosus (SLE) patients who suffer from dry eye syndrome. To this date, dry eye syndrome in SLE patients is believed to be caused by secondary Sjogren syndrome (sSS). However, there is increasing evidence for possible independency of dry eye syndrome and sSS in patients suffering from autoimmune diseases. The purpose of this retrospective observational case series was to identify SLE patients without sSS who had dry eye syndrome, examine the correlation of different autoantibodies and dry eye severity, and determine the cause of dry eye in these patients.We included 49 consecutive SLE patients with dry eye who visited our dry eye clinic. In order to rule out sSS, these patients were all negative for anti-Sjogren's-syndrome-related antigen A and B (anti-SSA/SSB) and had no oral symptoms. Each patient's lupus activity was determined by serological tests including antidouble-stranded DNA antibody (anti-dsDNA), complement levels (C3, C4), erythrocyte sedimentation rate (ESR), and antinuclear antibody (ANA). Severity of dry eye syndrome was determined by corneal sensation (KSen), superficial punctuate keratopathy (SPK), Schirmer-I test (Schirmer), and tear film break-up time (TBUT). The autoantibodies and the dry eye parameters in each group were tested using the χ test or the Mann-Whitney U test for normally distributed or skewed data, respectively.The anti-dsDNA showed significant correlations with KSen (P < 0.001), SPK (P < 0.001), and Schirmer (P = 0.042) but not TBUT. The C3 showed significant correlations with KSen (P < 0.001), SPK (P < 0.001), and Schirmer (P = 0.014) but not TBUT. No correlations of dry eye parameters were observed between C4, ESR, and ANA.The major finding of this study was that the severity of dry eye syndrome in SLE patients without sSS was strongly correlated with anti-dsDNA and C3 but not with C4, ESR, and ANA.

Prevalence of systemic autoimmune rheumatic diseases and clinical significance of ANA profile: data from a tertiary hospital in Shanghai, China

It is necessary and useful to explore prevalence of various systemic autoimmune rheumatic diseases (SARDs) in patients with suspicion of having SARDs and to characterize antinuclear antibodies (ANA) profile for identifying different populations (SARDs and non-SARDs). A total of 5024 consecutive patients with available medical records were investigated, whose sera had been tested for ANA profile, including ANA, anti-dsDNA and anti-extractable nuclear antigen (ENA) antibodies, between 31 January 2012 and 26 March 2014. Only 594 (11.8%) patients were diagnosed with SARDs of those suspected with SARDs. The prevalence of systemic lupus erythematosus (SLE) was highest (3.2%), followed by rheumatoid arthritis (RA) (2.5%), primary Sjögren's syndrome (pSS) (1.7%), ankylosing spondylitis (AS) (1.5%), etc. Of females, SLE also showed the highest prevalence (6%), while of males, AS showed the highest prevalence (1.9%). The prevalence of most SARDs was closely associated with age, except mixed connective tissue disease (MCTD), and the variation characteristics among different age groups were different among various SARDs. The prevalence of ANA was significantly increased in most SARD patients [especially in SLE, systemic sclerosis (SSc) and MCTD]. For anti-ENA antibodies, in contrast to some autoantibodies associated with multiple SARDs (e.g. anti-SSA, SSB, nRNP), others were relatively specific for certain diseases, such as anti-dsDNA, Sm, histone, nucleosome and Rib-P for SLE, anti-SCL-70 for SSc and anti-Jo-1 for polymyositis/dermatomyositis (PM/DM). Of note, ANA profile appeared to be of little significance for AS, ANCA-associated vasculitis (AAV), polymyalgia rheumatic (PMR), adult-onset Still's disease (ASD) and Behcet's disease (BD). The younger were more likely to have the presence of anti-dsDNA, Sm, histone or Rib-P for SLE, and anti-SSA for RA or MCTD. No significant differences for frequencies of ANA and anti-ENA autoantibodies were found between sexes in most SARDs, with the exception of RA and AS. The present study suggests that, of patients with SARDs-like clinical manifestations, the proportion of those with true SARDS is small, for most of whom tests for autoantibodies are necessary and useful to help make a prompt and precise diagnosis.

Dysregulation of innate and adaptive serum mediators precedes systemic lupus erythematosus classification and improves prognostic accuracy of autoantibodies

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with a poorly understood preclinical stage of immune dysregulation and symptom accrual. Accumulation of antinuclear autoantibody (ANA) specificities is a hallmark of impending clinical disease. Yet, many ANA-positive individuals remain healthy, suggesting that additional immune dysregulation underlies SLE pathogenesis. Indeed, we have recently demonstrated that interferon (IFN) pathways are dysregulated in preclinical SLE. To determine if other forms of immune dysregulation contribute to preclinical SLE pathogenesis, we measured SLE-associated autoantibodies and soluble mediators in samples from 84 individuals collected prior to SLE classification (average timespan = 5.98 years), compared to unaffected, healthy control samples matched by race, gender, age (±5 years), and time of sample procurement. We found that multiple soluble mediators, including interleukin (IL)-5, IL-6, and IFN-γ, were significantly elevated in cases compared to controls more than 3.5 years pre-classification, prior to or concurrent with autoantibody positivity. Additional mediators, including innate cytokines, IFN-associated chemokines, and soluble tumor necrosis factor (TNF) superfamily mediators increased longitudinally in cases approaching SLE classification, but not in controls. In particular, levels of B lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL) were comparable in cases and controls until less than 10 months pre-classification. Over the entire pre-classification period, random forest models incorporating ANA and anti-Ro/SSA positivity with levels of IL-5, IL-6, and the IFN-γ-induced chemokine, MIG, distinguished future SLE patients with 92% (±1.8%) accuracy, compared to 78% accuracy utilizing ANA positivity alone. These data suggest that immune dysregulation involving multiple pathways contributes to SLE pathogenesis. Importantly, distinct immunological profiles are predictive for individuals who will develop clinical SLE and may be useful for delineating early pathogenesis, discovering therapeutic targets, and designing prevention trials.

Single-cell antibody nanowells: a novel technology in detecting anti-SSA/Ro60- and anti-SSB/La autoantibody-producing cells in peripheral blood of rheumatic disease patients

Background

Anti-SSA/Ro60 and anti-SSB/La are essential serological biomarkers for rheumatic diseases, specifically Sjögren’s syndrome (SS) and systemic lupus erythematosus (SLE). Currently, laboratory detection technology and platforms are designed with an emphasis on high-throughput methodology; therefore, the relationship of sensitivity with specificity remains a significant area for improvement. In this study, we used single-cell antibody nanowells (SCAN) technology to directly profile individual B cells producing antibodies against specific autoantigens such as SSA/Ro60 and SSB/La.

Methods

Peripheral blood mononuclear cells were isolated using Ficoll gradient. Fluorescently labeled cells were added to fabricated nanowells and imaged using a high-speed epifluorescence microscope. The microengraving process was conducted using printed slides coated with immunoglobulins. Printed slides were hybridized with fluorescence-conjugated immunoglobulin G (IgG), SSA/Ro60, and SSB/La antigens. Microarray spots were analyzed for nanowells with single live B cells that produced antigen-specific autoantibodies.

Results

Our results indicate that SCAN can simultaneously detect high frequencies of anti-SSA/Ro60 and anti-SSB/La with a specific IgG isotype in peripheral blood mononuclear cells of patients, as well as measure their individual secretion levels. The data showed that patients with SS and SLE exhibited higher frequency and greater concentration of anti-SSA/Ro60- and anti-SSB/La-producing B cells in the IgG isotype. Furthermore, individual B cells of patients produced higher levels of IgG-specific anti-SSA/Ro60 autoantibody, but not IgG-specific anti-SSB/La autoantibody, compared with healthy control subjects.

Conclusions

These results support the application of SCAN as a robust multiparametric analytical bioassay that can directly measure secretion of autoantibody and accurately report antigen-specific, autoantibody-producing cells.

Associations Between Selected Xenobiotics and Antinuclear Antibodies in the National Health and Nutrition Examination Survey, 1999-2004

BACKGROUND

Potential associations between background environmental chemical exposures and autoimmunity are understudied.

OBJECTIVES

Our exploratory study investigated exposure to individual environmental chemicals and selected mixtures in relation to the presence of antinuclear antibodies (ANA), a widely used biomarker of autoimmunity, in a representative sample of the U.S.

METHODS

This cross-sectional analysis used data on 4,340 participants from the National Health and Nutrition Examination Survey (1999-2004), of whom 14% were ANA positive, to explore associations between ANA and concentrations of dioxins, dibenzofurans, polychlorinated biphenyls, organochlorines, organophosphates, phenols, metals, and other environmental exposures and metabolites measured in participants' serum, whole blood, or urine. For dioxin-like compounds with toxic equivalency factors, we developed and applied a new statistical approach to study selected mixtures. Lognormal models and censored-data methods produced estimates of chemical associations with ANA in males, nulliparous females, and parous females; these estimates were adjusted for confounders and accommodated concentrations below detectable levels.

RESULTS

Several associations between chemical concentration and ANA positivity were observed, but only the association in males exposed to triclosan remained statistically significant after correcting for multiple comparisons (mean concentration ratio = 2.8; 95% CI: 1.8, 4.5; p < 0.00001).

CONCLUSIONS

These data suggest that background levels of most xenobiotic exposures typical in the U.S. population are not strongly associated with ANA. Future studies should ideally reduce exposure misclassification by including prospective measurement of the chemicals of concern and should track changes in ANA and other autoantibodies over time.

CITATION

Dinse GE, Jusko TA, Whitt IZ, Co CA, Parks CG, Satoh M, Chan EKL, Rose KM, Walker NJ, Birnbaum LS, Zeldin DC, Weinberg CR, Miller FW. 2016. Associations between selected xenobiotics and antinuclear antibodies in the National Health and Nutrition Examination Survey, 1999-2004. Environ Health Perspect 124:426-436; http://dx.doi.org/10.1289/ehp.1409345.

Potassium Channel Block and Novel Autoimmune-Associated Long QT Syndrome

This article reviews advances in the pathogenesis of anti-SSA/Ro antibody-induced corrected QT (QTc) prolongation in patients with autoimmune diseases; particularly connective tissue disease (CTD). Evidence shows that anti-SSA/Ro antibody-positive patients with CTD show QTc prolongation and complex ventricular arrhythmias. Molecular and functional data provide evidence that the human ether-a-go-go-related gene potassium channel conducting the rapidly activating delayed rectifier potassium current is directly inhibited by anti-SSA/Ro antibodies, resulting in action potential duration prolongation leading to QT interval lengthening. Routine electrocardiogram screening in anti-SSA/Ro antibody-positive patients and counseling for patients with other QTc prolonging risk factors is recommended.

Diagnostic Evaluation of ELISA and Chemiluminescent Assays as Alternative Screening Tests to Indirect Immunofluorescence for the Detection of Antibodies to Cellular Antigens

OBJECTIVES

Detection of antinuclear antibodies (ANAs) plays an important role in the diagnosis of systemic autoimmune rheumatic disease (SARD). Our goal was to evaluate the diagnostic accuracy of three commercially available enzyme-linked immunosorbent assay (ELISA) kits and one chemiluminescent assay for ANA detection, using the clinical diagnostic as the reference standard.

METHODS

We evaluated serum samples from 143 patients with an established diagnosis of SARD (group 1), 166 patients with infectious diseases and other rheumatic diseases for which the ANA test is not useful in diagnosis (group 2), and 89 outpatients with suspicion of SARD (group 3).

RESULTS

The sensitivity for ANA HEp-2, calculated in group 1, was 87.4% and varied between 62.9% and 90.0% for other tests. The specificity for ANA HEp-2, calculated in group 2, was 72.3% and varied between 45.2% and 90.4% for other tests. In group 3, the negative predictive value for ANA Hep-2 was 92.5% and varied between 89.3% and 100% for other tests.

CONCLUSIONS

Some ELISA kits have comparable or superior diagnostic sensitivity to ANA HEp-2 and could be used as an alternative method for ANA screening, therefore allowing the immediate report of the results with fewer false negatives than ANA HEp-2. Owing to the lower specificity, ELISA-positive samples should be submitted to ANA HEp-2 for confirmation of results.

Systemic lupus erythematosus and primary fibromyalgia can be distinguished by testing for cell-bound complement activation products

OBJECTIVE

We sought to establish the performance of cell-bound complement activation products (CB-CAPs) as a diagnostic tool to distinguish primary fibromyalgia (FM) from systemic lupus erythematosus (SLE).

METHODS

A total of 75 SLE and 75 primary FM adult subjects who fulfilled appropriate classification criteria were enrolled prospectively. CB-CAPs (erythrocyte-C4d (EC4d) and B-lymphocyte-C4d (BC4d)) were determined by flow cytometry. Antinuclear antibodies (ANAs) were determined using indirect immunofluorescence while other autoantibodies were determined by solid-phase assays. The CB-CAPs in a multi-analyte assay with algorithm (MAAA) relied on two consecutive tiers of analysis that was reported as an overall positive or negative assessment. Test performance was assessed using sensitivity, specificity, positive and negative likelihood ratio (LR).

RESULTS

ANAs yielded 80% positives for SLE and 33% positives for FM. High CB-CAP expression (EC4d >14 units or BC4d >60 units) was 43% sensitive and 96% specific for SLE. The CB-CAPs in MAAA assessment was evaluable in 138 of the 150 subjects enrolled (92%) and yielded 60% sensitivity (CI 95% 48% to 72%) for SLE with no FM patient testing positive (100% specificity). A positive test result was associated with a strong positive LR for SLE (>24, CI 95%; 6 to 102), while a negative test result was associated with a moderate negative LR (0.40; CI 95% 0.30 to 0.54).

CONCLUSION

Our data indicate that CB-CAPs in MAAA can distinguish FM from SLE.

Serum antinuclear and extractable nuclear antigen antibody prevalence and associated morbidity and mortality in the general population over 15 years

The prevalence of ANA and anti-ENA in the general population is not well established, especially their clinical significance in healthy subjects. We herein determined the prevalence and predictive value of serum ANA and anti-ENA for connective tissue diseases (CTD), cancer, and mortality. We took advantage of a randomly selected sample of the 1998 general population (Isola I) consisting of 2828 subjects (53% women, age 43±13 years) from a well-defined Northern Italian area. Serum ANA and anti-ENA were tested on the 2690 samples available in 2012 (Isola II, 50% women, age 58±13 years). Administrative databases were searched for CTD, cancer diagnosis, and death cases occurring between enrollment and December 31, 2013. The hazard ratio (HR) was calculated for incident cases. Serum ANA is positive in 18.1% for any titer and 6.1% for titers ≥1:160, 23% in subjects over 50 years and 13.1% and 6.1% for any titer and titers ≥1:160, respectively, in women. The HR for CTD development was significantly high for all ANA titers, with the highest for ANA ≥1:160 (HR 14.19, 95% CI 3.07-65.68). ANA positivity was not associated with cancer (HR 1.03; 95% CI 0.75-1.43), or with mortality (HR adjusted for age and sex 1.40; 95% CI 0.94-2.09). Serum anti-ENA is positive in a minority of subjects with highest figures for anti-nucleosome (1.9%), -histone (1.6%) and -PM/Scl (1.5%). In conclusion, serum ANA prevalence in the general population is highest in senior subjects and in women, while the female predominance is significantly lower compared to overt CTD. Serum ANA is associated with an increased probability of CTD development over time, but does not influence survival or cancer risk.

Gilles de la Tourette syndrome is not linked to contactin-associated protein receptor 2 antibodies

BACKGROUND

In Gilles de la Tourette syndrome (GTS) an immunopathogenic influence of autoantibodies is suspected. In familial GTS a disruption of the contactin-associated protein 2 gene (CNTNAP2), coding for the contactin-associated protein 2 (CASPR2), has been reported. Autoantibodies against CASPR2 are associated with other movement disorders like Morvan's syndrome. In addition, positive oligoclonal bands (OCB) in cerebrospinal fluid (CSF) have been found in more than a third of GTS patients, indicating a pathological intrathecal immunoglobulin synthesis. These findings drove the hypothesis that CASPR2 antibodies are involved in GTS.

METHODS

In this cross sectional study, 51 patients with GTS were examined for CASPR2 and other autoantibodies. We used indirect immunofluorescence or enzyme-linked visualization in cell-based assays on tissue sections from cerebellum (rat and monkey), hippocampus (rat), and immunoblots for the detection of specific or any other autoantibodies.

RESULTS

Serum samples from 51 GTS patients, mean age 35.0 ± 13.1 y, were analyzed. In none of the 51 GTS sera CASPR2 antibodies were detectable. Neither had we found any other specific autoantibodies (LGI1, NMDAR, AMPA1, AMPA/2 or GABAB1/B2). An anti-nuclear pattern of immunoreactivity was observed in 7/51 (14 %) samples. In these patients an immunoblot analysis was used to rule out antibodies directed against well-defined intracellular target antigens. A specific anti-neuronal binding pattern could not be seen in any of the tissue sections.

CONCLUSIONS

The results negate that CASPR2 antibodies play a role in the pathogenesis of Tourette syndrome and do not support the assumption that anti-neuronal antibodies are involved.

Mercury Exposure and Antinuclear Antibodies among Females of Reproductive Age in the United States: NHANES

BACKGROUND

Immune dysregulation associated with mercury has been suggested, although data in the general population are lacking. Chronic exposure to low levels of methylmercury (organic) and inorganic mercury is common, such as through fish consumption and dental amalgams.

OBJECTIVE

We examined associations between mercury biomarkers and antinuclear antibody (ANA) positivity and titer strength.

METHODS

Among females 16-49 years of age (n = 1,352) from the National Health and Nutrition Examination Survey (NHANES) 1999-2004, we examined cross-sectional associations between mercury and ANAs (indirect immunofluorescence; cutoff ≥ 1:80). Three biomarkers of mercury exposure were used: hair (available 1999-2000) and total blood (1999-2004) predominantly represented methylmercury, and urine (1999-2002) represented inorganic mercury. Survey statistics were used. Multivariable modeling adjusted for several covariates, including age and omega-3 fatty acids.

RESULTS

Sixteen percent of females were ANA positive; 96% of ANA positives had a nuclear speckled staining pattern. Geometric mean (geometric SD) mercury concentrations were 0.22 (0.03) ppm in hair, 0.92 (0.05) μg/L blood, and 0.62 (0.04) μg/L urine. Hair and blood, but not urinary, mercury were associated with ANA positivity (sample sizes 452, 1,352, and 804, respectively), after adjusting for confounders: for hair, odds ratio (OR) = 4.10 (95% CI: 1.66, 10.13); for blood, OR = 2.32 (95% CI: 1.07, 5.03) comparing highest versus lowest quantiles. Magnitudes of association were strongest for high-titer (≥ 1:1,280) ANA: hair, OR = 11.41 (95% CI: 1.60, 81.23); blood, OR = 5.93 (95% CI: 1.57, 22.47).

CONCLUSIONS

Methylmercury, at low levels generally considered safe, was associated with subclinical autoimmunity among reproductive-age females. Autoantibodies may predate clinical disease by years; thus, methylmercury exposure may be relevant to future autoimmune disease risk.

An Unusual Mimicker of Systemic Lupus Erythematosus: A Case Report

We present a case of a 47 year-old African American female with 15 pack-years of tobacco use and heavy alcohol use who presented with arthritis and was found to have a positive antinuclear antibodies (ANA), anti double stranded DNA antibodies (anti-dsDNA), and anti-Sjogren's syndrome-related antigen A and antigen B (anti-SSA and anti-SSB). She was subsequently found to have a lung adenocarcinoma associated with hypertrophic pulmonary osteoarthropathy (HPO). This demonstrates a case of positive antinuclear antibodies and arthritis in a patient with lung adenocarcinoma, which can be falsely diagnosed as systemic lupus erythematosus.

The prevalence of antinuclear antibodies in patients with schizophrenia spectrum disorders: results from a large cohort study

Background:

An increased prevalence of autoantibodies has been found in patients with schizophrenia, suggesting a role for autoimmunity in schizophrenia pathogenesis.

Methods:

We examined the presence of antinuclear antibodies (ANAs), with further determination of specific antibodies, in 368 patients with a schizophrenia spectrum disorder and 283 healthy controls.

Results:

No significant difference in prevalence of ANAs between patients (8%) and controls (11%) was found.

Conclusion:

We did not find an association between ANAs and schizophrenia spectrum disorders. We discuss potential reasons for the discrepancy with some previous studies, such as inclusion of patients using chlorpromazine, which can induce ANAs.

Should we systematically test patients with clinically isolated syndrome for auto-antibodies?

Background:

Several autoimmune diseases (ADs) can mimic multiple sclerosis (MS). For this reason, testing for auto-antibodies (auto-Abs) is often included in the diagnostic work-up of patients with a clinically isolated syndrome (CIS).

Objective:

The purpose was to study how useful it was to systematically determine antinuclear-antibodies, anti-SSA and anti-SSB in a non-selected cohort of CIS patients, regarding the identification of other ADs that could represent an alternative diagnosis.

Methods:

From a prospective CIS cohort, we selected 772 patients in which auto-Ab levels were tested within the first year from CIS. Baseline characteristics of auto-Ab positive and negative patients were compared. A retrospective revision of clinical records was then performed in the auto-Ab positive patients to identify those who developed ADs during follow-up.

Results:

One or more auto-Ab were present in 29.4% of patients. Only 1.8% of patients developed other ADs during a mean follow-up of 6.6 years. In none of these cases the concurrent AD was considered the cause of the CIS. In all cases the diagnosis of the AD resulted from the development of signs and/or symptoms suggestive of each disease.

Conclusion:

Antinuclear-antibodies, anti-SSA and anti-SSB should not be routinely determined in CIS patients but only in those presenting symptoms suggestive of other ADs.

Multidisciplinary clinic dedicated to treating youth with pediatric acute-onset neuropsychiatric syndrome: presenting characteristics of the first 47 consecutive patients

BACKGROUND

Abrupt, dramatic onset obsessive-compulsive disorder (OCD) and/or eating restriction with at least two coinciding symptoms (anxiety, mood dysregulation, irritability/aggression/oppositionality, behavioral regression, cognitive deterioration, sensory or motor abnormalities, or somatic symptoms) defines pediatric acute-onset neuropsychiatric syndrome (PANS). Descriptions of clinical data in such youth are limited.

METHODS

We reviewed charts of 53 consecutive patients evaluated in our PANS Clinic; 47 met PANS symptom criteria but not all met the requirement for "acute onset." Patients meeting full criteria for PANS were compared with patients who had a subacute/insidious onset of symptoms.

RESULTS

Nineteen of 47 (40%) patients in the study had acute onset of symptoms. In these patients, autoimmune/inflammatory diseases and psychiatric disorders were common in first-degree family members (71% and 78%, respectively). Most acute-onset patients had a relapsing/remitting course (84%), prominent sleep disturbances (84%), urinary issues (58%), sensory amplification (66%), gastrointestinal symptoms (42%), and generalized pain (68%). Inflammatory back pain (21%) and other arthritis conditions (28%) were also common. Suicidal and homicidal thoughts and gestures were common (44% and 17%, respectively) as were violent outbursts (61%). Group A streptococcus (GAS) was the most commonly identified infection at onset (21%) and during flares (74%). Rates of the above-mentioned characteristics did not differ between the acute-onset group and the subacute/insidious-onset groups. Low levels of immunoglobulins were more common in the subacute/insidious-onset group (75%) compared with the acute-onset group (22%), but this was not statistically significant (p=0.06).

CONCLUSIONS

In our PANS clinic, 40% of patients had acute onset of symptoms. However, those with and without acute onset of symptoms had similar symptom presentation, rates of inflammatory conditions, somatic symptoms, and violent thoughts and behaviors. GAS infections were the most commonly identified infection at onset and at symptom flares. Because of the wide variety of medical and psychiatric symptoms, youth with PANS may require a multidisciplinary team for adequate care management.

Clinical evaluation of youth with pediatric acute-onset neuropsychiatric syndrome (PANS): recommendations from the 2013 PANS Consensus Conference

On May 23 and 24, 2013, the First PANS Consensus Conference was convened at Stanford University, calling together a geographically diverse group of clinicians and researchers from complementary fields of pediatrics: General and developmental pediatrics, infectious diseases, immunology, rheumatology, neurology, and child psychiatry. Participants were academicians with clinical and research interests in pediatric autoimmune neuropsychiatric disorder associated with streptococcus (PANDAS) in youth, and the larger category of pediatric acute-onset neuropsychiatric syndrome (PANS). The goals were to clarify the diagnostic boundaries of PANS, to develop systematic strategies for evaluation of suspected PANS cases, and to set forth the most urgently needed studies in this field. Presented here is a consensus statement proposing recommendations for the diagnostic evaluation of youth presenting with PANS.

Effects of smoking and shared epitope on the production of anti-citrullinated peptide antibody in a Japanese adult population

OBJECTIVE

Anti-citrullinated peptide antibody (ACPA) and rheumatoid factor (RF) are markers to rheumatoid arthritis (RA). Smoking and shared epitope (SE) in HLA-DRB1 are associated with the production of these autoantibodies in RA. Detailed distribution and characterization of ACPA and RF in the general population have remained unclear. We aimed to evaluate positivity of ACPA and RF in a general Japanese population and to detect correlates, including genetic components.

METHODS

ACPA and RF were quantified in 9,804 Japanese volunteers ages 30-75 years. Logistic regression analyses were performed to evaluate the effects of candidates of correlates on the autoantibody positivity. A genome-wide association study (GWAS) was performed using 394,239 single nucleotide polymorphisms for 3,170 participants, and HLA-DRB1 alleles were imputed based on the GWAS data.

RESULTS

A total of 1.7% and 6.4% of subjects were positive for ACPA and RF, respectively, and the 2 markers showed a significant correlation (P = 2.0 × 10(-23) ). Old age was associated with ACPA positivity (P = 0.00062). Sex, smoking, SE, and other candidates of correlates did not have significant effects. Interaction between smoking and SE positivity was not apparent, but smoking showed a significant association with high levels of ACPA (P = 0.0019).

CONCLUSION

ACPA and RF could be detected in 1.7% and 6.4% of the Japanese adult population without RA, respectively. ACPA and RF were suggested to share mechanisms even in healthy populations. Old age was associated with increasing ACPA positivity. While positivity of ACPA and RF was not associated with SE and smoking, an association between high ACPA and smoking was observed.

Diagnostic profile on the IFA 40: HEp-20-10 - an immunofluorescence test for reliable antinuclear antibody screening

Indirect immunofluorescence assay is the recommended gold standard to test for antinuclear antibodies (ANA), which are important biomarkers for systemic rheumatic autoimmune diseases. It is internationally accepted that indirect immunofluorescence assay ANA screening is most sensitive on human epithelial (HEp-2) cells. The cells present a multitude of antigens that display distinguishable localization patterns in interphase and mitotic cells in indirect immunofluorescence analysis. Here, we present the IFA 40: HEp-20-10 test kit (Euroimmun AG, Lübeck, Germany), which is cleared for sale on the US market by the FDA. The test has been designed for qualitative and semiquantitative screening of ANA in human sera. It uses the commonly applied 1:40 cutoff dilution and the enhanced HEp-20-10 cell line for more efficient pattern recognition and has been validated in various studies and by method comparison. The IFA 40: HEp-20-10 test fulfills the essential criteria for reliable application in autoimmune diagnostics.

The prevalence of antinuclear antibodies in the general population of china: a cross-sectional study

BACKGROUND

The incidence of autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, and primary biliary cirrhosis has increased significantly in China. Information about the susceptibility or potential of autoimmune diseases in the general population is lacking.

OBJECTIVE

To explore the prevalence of antinuclear antibody (ANA) and its specificities in the general population in China.

METHODS

Twenty thousand nine hundred seventy sera samples were taken from the physical examination center in Baoding, China. Indirect immunofluorescence and line immunoassays were used to detect ANA and its specificities, respectively.

RESULTS

Samples from females had a higher prevalence of ANA than samples from males (χ(2) = 278.55; P < 0.01). For both sexes, the prevalence of ANA positively correlated with age and there were significant differences among different age groups at 10-year intervals, except the 80 years group (P < 0.05). One thousand two hundred forty-three ANA-positive samples were further analyzed with line immunoassays. There was a significant difference among age groups and between sex groups in terms of the specific autoantibodies (P < 0.01). The autoantibodies with the top-3 positive frequencies were anti-Ro-52, anti-M2, and anti-SSA.

CONCLUSIONS

There was a high prevalence of ANA positivity in the general Chinese population that seemed to be influenced by sex and age and correlated with specific autoantibodies.

Autoimmunity and autoinflammation as the yin and yang of idiopathic recurrent acute pericarditis

Autoimmunity and autoinflammation are generally considered as mutually exclusive mechanisms of diseases but may concur to specific syndromes. Idiopathic recurrent acute pericarditis (IRAP) is defined as the recurrence of pericardial symptoms at any point following the prior cessation of acute pericarditis, and the latency is generally 6 weeks. Manifestations of pericarditis such as pericardial friction rub, electrocardiographic changes, and pericardial effusion are less frequent in the subsequent episodes compared to the index attack, and in some cases the only clinical sign is represented by a suggestive chest pain. Several autoimmune diseases may manifest with pericarditis which is often related to viral infections, while postviral pericarditis may in turn display a nonspecific autoimmune background. Similarly, autoinflammatory syndromes such as familial Mediterranean fever and tumor necrosis factor receptor-associated periodic syndrome are characterized by self-limiting pericardial symptoms. Corticosteroids are generally effective, thus supporting the autoimmune nature of IRAP, but dramatic results are obtained with interleukin-1 blocking agents in corticosteroid-dependent cases, pointing to a pathogenic role for the inflammasome. Based on these observations, we submit that IRAP represents a paradigmatic example of the putative coexistence of autoimmunity and autoinflammation: the main aim of this review is to critically discuss the hypothesis as well as the current understanding of this enigmatic clinical condition.

Cell-bound complement activation products in systemic lupus erythematosus: comparison with anti-double-stranded DNA and standard complement measurements

OBJECTIVE

To compare the performance characteristics of cell-bound complement (C4d) activation products (CBCAPS) on erythrocyte (EC4d) and B cells (BC4d) with antibodies to double-stranded DNA (anti-dsDNA) and complement C3 and C4 in systemic lupus erythematosus (SLE).

METHODS

The study enrolled 794 subjects consisting of 304 SLE and a control group consisting of 285 patients with other rheumatic diseases and 205 normal individuals. Anti-dsDNA and other autoantibodies were measured using solid-phase immunoassays while EC4d and BC4d were determined using flow cytometry. Complement proteins were determined using immunoturbidimetry. Disease activity in SLE was determined using a non-serological Systemic Lupus Erythematosus Disease Activity Index SELENA Modification. A two-tiered methodology combining CBCAPS with autoantibodies to cellular and citrullinated antigens was also developed. Statistical analyses used area under receiver operating characteristic curves and calculations of area under the curve (AUC), sensitivity and specificity.

RESULTS

AUC for EC4d (0.82±0.02) and BC4d (0.84±0.02) was higher than those yielded by C3 (0.73±0.02) and C4 (0.72±0.02) (p<0.01). AUC for CBCAPS was also higher than the AUC yielded by anti-dsDNA (0.79±0.02), but significance was only achieved for BC4d (p<0.01). The combination of EC4d and BC4d in multivariate testing methodology with anti-dsDNA and autoantibodies to cellular and citrullinated antigens yielded 80% sensitivity for SLE and specificity ranging from 70% (Sjogren's syndrome) to 92% (rheumatoid arthritis) (98% vs. normal). A higher proportion of patients with SLE with higher levels of disease activity tested positive for elevated CBCAPS, reduced complement and anti-dsDNA (p<0.03).

CONCLUSIONS

CBCAPS have higher sensitivity than standard complement and anti-dsDNA measurements, and may help with the differential diagnosis of SLE in combination with other autoantibodies.

Clinical and pathologic differences in interstitial lung disease based on antisynthetase antibody type

BACKGROUND

Interstitial lung disease (ILD) is a common extramuscular manifestation of the idiopathic inflammatory myopathies (IIMs), dermatomyositis (DM) and polymyositis (PM). Patients with antisynthetase antibodies (ASA) demonstrate some or all of the features of the antisynthetase syndrome including IIM and ILD. It has been hypothesized that the clinical expression of antisynthetase syndrome varies between specific ASAs.

OBJECTIVE

We sought to determine whether the myositis-associated ILD (MA-ILD) phenotype differs based on the presence of ASAs and by ASA subtype.

METHODS

A cross-sectional and longitudinal analysis of consecutive patients enrolled at the Johns Hopkins Myositis Center with ILD in the setting of clinically diagnosed autoimmune myositis was conducted.

RESULTS

Seventy-seven subjects were included; 36 were ASA negative, 28 were anti-Jo1 positive, and 13 were non-Jo1 ASA positive (5 anti-PL-12, 4 anti-PL-7, 2 anti-EJ, and 2 anti-OJ). Non-Jo1 ASA positive participants were more likely to be African-American than Caucasian as compared to both the anti-Jo1 positive (p = 0.01) and ASA negative groups (p < 0.01). ASA negative participants had better mean forced vital capacity percent predicted (FVC%) and total computed tomography scores over time compared to those with anti-Jo1 after controlling for potential confounders.

CONCLUSIONS

ASA status was significantly different by race. Those with anti-Jo1 antibodies had worse lung function and CT scores over time compared to those without detectable antisynthetase antibodies. Further prospective study in a larger cohort is needed to determine whether these apparent antibody-specific differences in demographics and manifestations of disease translate into meaningful disparities in clinical outcomes.

Is preclinical autoimmunity benign?: The case of cardiovascular disease

Although there are many examples of autoantibodies in disease-free individuals, they can be a preclinical phenomenon heralding future autoimmune rheumatic disease. They may be a marker for autoreactive B-cell activation and other inflammatory autoimmune processes. The increased prevalence of cardiovascular disease (CVD) in autoimmune rheumatic diseases such as rheumatoid arthritis and systemic lupus erythematosus, and the increased risk of CVD in patients with rheumatic disease with autoantibodies, suggest that CVD may have autoimmune features. Autoantibodies might be risk markers for subclinical and clinical CVD development not only in patients with rheumatic diseases but in the general population as well.

Reproductive and hormonal risk factors for antinuclear antibodies (ANA) in a representative sample of U.S. women

BACKGROUND

Autoantibodies are of growing interest in cancer research as potential biomarkers; yet, the determinants of autoimmunity are not well understood. Antinuclear antibodies (ANA) are common in the general population and are more prevalent in women and older adults. Here, we examined the relationship of ANA with reproductive and hormonal factors in a representative sample of U.S. women.

METHODS

We analyzed data on reproductive history and exogenous hormone use in relation to serum ANA in 2,037 females ages 12 years and older from the National Health and Nutrition Examination Survey (NHANES; 1999-2004). Estimated ANA prevalences were adjusted for sampling weights. Prevalence ORs (POR) and 95% confidence intervals (CI) were adjusted for age, race, and poverty-income ratio, and models were stratified by menopause status.

RESULTS

In premenopausal women ages 20 years and older, ANA prevalence was associated with parity (P < 0.001; parous vs. nulliparous POR = 2.0; 95% CI, 1.2-3.4), but in parous women, ANA did not vary by number of births, age at first birth, years since last birth, or breastfeeding. In postmenopausal women, ANA prevalence was associated with an older age at menarche (P = 0.019; age 16-20 vs. 10-12 years POR = 3.0; 95% CI, 1.6-5.9), but not with parity. Oral contraceptives and estrogen therapy were not associated with a higher ANA prevalence.

CONCLUSIONS

Childbearing (having had one or more births) may explain age-associated elevations in ANA prevalence seen in premenopausal women.

IMPACT

These findings highlight the importance of considering reproductive history in studies of autoimmunity and cancer in women.

Development of positive antinuclear antibodies and rheumatoid factor in systemic juvenile idiopathic arthritis points toward an autoimmune phenotype later in the disease course

BACKGROUND

Systemic juvenile idiopathic arthritis (sJIA) is commonly considered an autoinflammatory disease. However, sJIA patients may develop aggressive arthritis without systemic inflammation later in the disease, resembling an autoimmune phenotype similar to other subtypes of JIA. The objective of this study was to determine whether antinuclear antibodies (ANA) and rheumatoid factor (RF) will develop in patients with sJIA over the course of the disease.

FINDINGS

A single center sample of sJIA patients with follow-up of more than one year was obtained. A retrospective chart survey was used to extract demographic and clinical data as well as presence and titers of ANA and RF at diagnosis and during follow-up. 32 patients were included in the study, with a median age of 4.2 years and median follow-up of 6.0 years. 8/32 patients had ANA titers ≥ 1:80 at diagnosis, with 22/32 patients showing rising ANA titers with titers ≥ 1:80 at last follow-up (p =0.001). 10/32 patients had a positive RF at least once during follow-up, compared to 0/32 at diagnosis (p = 0.001). In 5/10 patients, positive RF was documented at least twice, more than twelve weeks apart. Patients treated with TNF antagonists were not significantly more likely to develop positive ANA titers (p = 0.425) or positive RF (p = 0.703).

CONCLUSIONS

Patients with sJIA developed increased ANA titers and positive RF over the course of the disease, independent of treatment with TNF antagonists. This might point towards an autoimmune, rather than an autoinflammatory phenotype later in the course of sJIA.

Acute inflammatory arthritis in the elderly; Old flames, new sparks

BACKGROUND

The overall world prevalence of rheumatoid arthritis (RA) ranges from 0.5-1.0%. The annual incidence of RA in most European countries ranges from roughly 0.4 to >2.5 per 1,000 adults, increasing with age. A significant proportion of newly diagnosed cases will evolve into true erosive RA.

METHODS

The aim of this cohort study was to study the characteristics of new developing, acute (<1 year), rheumatoid arthritis in an elderly (>65 years) population; its presenting features, accompanying manifestations and laboratory findings. One hundred twenty eight patients (103♀, 25♂) who presented to the rheumatology outpatients clinic with new-onset RA were included in the study. 42.2% of the patients had pre-existing osteoarthritis.

RESULTS

At presentation, 14.3% of the patients had systemic manifestations (fever, weight loss), 25.78% reported concomitant sicca symptomatology, and 50.9% were found to have abnormal haematological parameters (anemia and/or thrombocytosis). Clinical and laboratory parameters of the disease were analyzed and related to disease manifestations.. Haematological abnormalities were found to be associated both with increased inflammatory markers, as well as with increased titres of rheumatoid factor (RF), but not anti - cyclic citrullinated peptide (CCP) antibodies, in contrary to systemic manifestations which were not found to be related to the above mentioned parameters.

CONCLUSIONS

As the global population is becoming older, physicians will be challenged with the recognition and treatment of these conditions and their particular features in an increasing number of geriatric patients; within the context of the specific characteristics and comorbidities of this age group. Hippokratia 2014; 18 (3): 231-233.

Autoantibodies to the Rpp25 component of the Th/To complex are the most common antibodies in patients with systemic sclerosis without antibodies detectable by widely available commercial tests

OBJECTIVE

Antinuclear antibodies (ANA) occur in up to 95% of patients with systemic sclerosis (SSc). In most, SSc-associated antibodies are detected (i.e., centromere, topoisomerase I, RNA polymerase III, PM/Scl, Ro52/TRIM21, and U1RNP). Ribonuclease P protein subunit p25, (Rpp25) is an autoantigenic component of the Th/To complex. The contribution of anti-Th/To and anti-Rpp25 antibodies to ANA positivity in patients with SSc remains unknown.

METHODS

Sera from 873 patients with SSc were tested for ANA, and SSc-associated antibodies were measured. Samples without antibodies to extractable nuclear antigens (ENA; n = 53, ANA+/ENA-), were analyzed by immunoprecipitation (IP) and metabolically labeled proteins and for anti-Rpp25 antibodies (n = 50) by a chemiluminescent immunoassay (CLIA) and Rpp25 ELISA.

RESULTS

Anti-Th/To antibodies occurred in 19/53 (36%), as determined by IP, and were the most common autoantibody in ANA+/ENA- SSc. Of those samples, 50/53 were available for additional testing by CLIA and ELISA. Anti-Rpp25 antibodies were detected in 12 (24% CLIA) or 10 (20% ELISA) of 50 patients. Receiver-operating characteristic curve analysis showed similar discrimination between Th/To IP-positive (n = 19) and -negative samples (n = 31) by CLIA and ELISA (area under the curve 0.90 vs 0.87; p = 0.6691). The positive percent agreement between IP and CLIA or ELISA was 12/19 (63.2%, 95% CI 38.4-83.7%) or 10/19 (52.6%, 95% CI 73.3-94.2%), respectively. Negative percent agreement was 100% for both assays.

CONCLUSION

Autoantibodies to the Th/To autoantigen are important in patients with SSc who have been considered negative for SSc-specific or SSc-associated antibodies by widely available commercial assays. Rpp25 can be considered a major target of anti-Th/To antibodies. Assays detecting anti-Th/To and anti-Rpp25 antibodies may be important in SSc.