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

Antinuclear Antibodies in Non-Rheumatic Diseases

Antinuclear antibodies (ANAs) are critical immunological markers commonly associated with various connective tissue diseases (CTDs). However, these autoantibodies are also detectable in healthy individuals, patients with non-rheumatic autoimmune diseases, those with viral infections, and subjects using specific medications (such as procainamide, hydralazine, and minocycline) that can lead to drug-induced ANA elevation. The standard method for ANA detection is indirect immunofluorescence, a process that requires precision and thoroughness as it assesses both titer and fluorescence patterns. Additionally, immunoblotting and enzyme-linked immunosorbent assay (ELISA) are recommended to identify specific ANAs precisely, highlighting the importance of precision in ANA detection. This review explores the advantages and limitations of current ANA detection methods. It also describes the clinical implications of ANA presence in non-rheumatic diseases, including autoimmune disorders, infectious conditions, non-autoimmune and non-infectious diseases, and autoimmune cutaneous diseases. The presence of elevated ANA titers in these contexts can complicate clinical decision-making, as the diagnostic value of ANA testing alone is limited in non-rheumatic conditions. However, despite these limitations, ANA remains a key component in diagnosing and prognosis systemic CTDs, as it can indicate disease activity, severity, and response to treatment, which is of utmost importance in rheumatology and internal medicine. This paper provides a comprehensive review of the role of ANA in non-rheumatic diseases. It focuses on ANA diagnostic and prognostic significance and offers valuable insights for clinical practice.

[Humoral Immunity Abnormalities in Advanced Maternal-Age Women With Recurrent Spontaneous Abortion: A Single Center Study]

Objective

To determine the humoral immunity in advanced maternal-age women with recurrent spontaneous abortion (RSA).

Methods

A retrospective study was performed between January 2022 and October 2023 in the Department of Reproductive Immunity of Shanghai First Maternity and Infant Hospital. Women with RSA were recruited and multiple autoantibodies were tested. Multivariate logistic regression was performed to compare the associations between different age groups (20 to 34 years old in the low maternal-age group and 35 to 45 years in the advanced maternal-age group) and multiple autoantibodies, while controlling for three confounding factors, including body mass index (BMI), previous history of live birth, and the number of spontaneous abortions. Then, we investigated the differences in the humoral immunity of advanced maternal-age RSA women and low maternal-age RSA women.

Result

A total of 4009 women with RSA were covered in the study. Among them, 1158 women were in the advanced maternal-age group and 2851 women were in the low maternal-age group. The prevalence of antiphospholipid syndrome, systemic lupus erythematosus, Sjogren's syndrome, rheumatoid arthritis, and undifferentiated connective tissue disease was 15.6% and 14.1%, 0.0% and 0.1%, 0.9% and 0.9%, 0.3% and 0.0%, and 23.7% and 22.6% in the advanced maternal-age group and low maternal-age group, respectively, showing no statistical difference between the two groups. The positive rates of antiphospholipid antibodies (aPLs), antinuclear antibody (ANA), extractable nuclear antigen (ENA) antibody, anti-double stranded DNA (dsDNA) antibody, anti single-stranded DNA (ssDAN) antibody, antibodies against alpha-fodrin (AAA), and thyroid autoimmunity (TAI) were 19.1% and 19.5%, 6.6% and 6.6%, 9.2% and 10.5%, 2.0% and 2.0%, 2.2% and 1.2%, 5.1% and 4.9%, and 17.8% and 16.8%, respectively. No differences were observed between the two groups. 1.6% of the women in the advanced maternal-age group tested positive for lupus anticoagulant (LA), while 2.7% of the women in the low maternal-age group were LA positive, with the differences being statistically significant (odds ratio=0.36, 95% confidence interval: 0.17-0.78). In the 4008 RSA patients, the cumulative cases tested positive for the three antibodies of the aPLs spectrum were 778, of which 520 cases were positive for anti-β2 glycoprotein Ⅰ antibodies (β2GPⅠ Ab)-IgG/IgM, 58 were positive for aCL-IgG/IgM, 73 were positive for LA, 105 were positive for both β2GPⅠ Ab-IgG/IgM and aCL-IgG/IgM, 17 were positive for both β2GPⅠ Ab-IgG/IgM and LA, 2 were positive for both aCL-IgG/IgM and LA, and 3 were positive for all three antibodies.

Conclusion

Our study did not find a difference in humoral immunity between RSA women of advanced maternal age and those of low maternal age.

Clinical usefulness of anti-nuclear antibody in childhood: real-world experience at a tertiary care center : Usefulness of ANA in pediatric autoimmune diseases

We evaluated the reasons for requesting anti-nuclear antibody (ANA) analysis in clinical practice at a tertiary center and the performance of ANA in pediatric autoimmune diseases. Patients under 18 years of age who underwent ANA testing for various symptoms between 2013 and 2017 were included. We retrieved data from medical records, including demographic and clinical characteristics, diagnoses, ANA results, titers, and staining patterns. The performance assessment tools were calculated according to the ANA titer for autoimmune diseases. Risk factors for autoimmune diseases in ANA-positive patients were evaluated using logistic regression analysis. Changes in ANA titer and seroconversion were evaluated using repeated ANA analyses. A total of 3812 patients underwent ANA. Medical records of 3320 patients were obtained. The rate of ANA positivity was 27.4%. ANA was requested most frequently because of musculoskeletal findings in 1355 patients (40.8%). Juvenile idiopathic arthritis (n = 174, 20.2%) was the most common diagnosis in ANA-positive patients, followed by systemic lupus erythematosus (n = 52, 6%). For autoimmune diseases, a titer of ≥ 1:100, a sensitivity of 40.1%, and a specificity of 77.1% were observed. At a titer ≥ 1:1000, the sensitivity and specificity were 24.1% and 89%, respectively. Homogeneous staining was an additional risk factor for autoimmune diseases in ANA-positive patients by multivariate logistic regression analysis (OR [95% CI]: 4.562 [3.076-6.766], p < 0.001).    Conclusion: Our results revealed that the performance of the ANA test in diagnosing autoimmune diseases in pediatric clinical practice was poor. Therefore, clinical findings should be carefully evaluated before ANA testing is performed. What is Known: • ANA can be detected in systemic autoimmune rheumatic diseases. • The diagnostic role of ANA is controversial, especially in childhood. What is New: • One in four patients who requested the ANA test had an autoimmune disease. • Less than half of patients with an autoimmune disease had ANA positivity.

The effect of the BNT162b2 vaccine on antinuclear antibody and antiphospholipid antibody levels

The Food and Drug Administration (FDA) approved the first SARS-CoV-2 mRNA vaccine (Pfizer-BioNTech) in December 2020. New adverse events have emerged since these vaccines have reached market. Although no clear association between messenger ribonucleic acid (mRNA) vaccines and autoimmunity has emerged, the significance of such an association warrants further exploration. After obtaining consent, a standardized survey on baseline characteristics and other relevant variables was conducted on unvaccinated individuals who were scheduled for vaccination and had not previously contracted COVID-19. Blood samples were collected from participants prior to the first dose, prior to the second dose, and 1 month after the second dose. All collected samples were tested for antinuclear antibody (ANA) titers using indirect immunofluorescence microscopy kits, and antiphospholipid (APS) immunoglobulin M (IgM) and immunoglobulin G (IgG) levels using an enzyme-linked immunoassay (ELISA) technique. ANA titers were positive for 9 participants out of 101 (8.9%) in the first pre-vaccination draw. For the second draw, the number of participants testing positive for ANA decreased to 5 (5%). For the last draw, 6 (5.9%) participants tested positive for ANA titers. One participant tested positive for APS IgM at the first pre-vaccination draw, 2 tested positive at the second draw, and 2 at the third draw. As for APS IgG titers, all participants tested negative in the three draws. McNemar's test for two dependent categorical outcomes was conducted on all variables and did not show a statistical significance. The McNemar test of these two composite variables (i.e., ANA/APS, first draw vs. ANA/APS, second and third draws) did not show statistical significance. The 2-sided exact significance of the McNemar test was 1.0. The Friedman test also showed no significance (p = 0.459). No association was found between BNT162b2 vaccine administration and changes in APS and ANA titers. The benefits of the BNT162b2 vaccine significantly outweigh any possible risk of autoimmune dysregulation considering the current evidence.

The influence of demography and referral medical specialty on the detection of autoantibodies to HEP-2 cells in a large sample of patients

Background

The prevalence of anti-cell autoantibodies detected by indirect immunofluorescence assay on HEp-2 cells (HEp-2-IIFA) increases with age and is higher in female sex. The number of medical specialties that use HEp-2-IIFA in the investigation of autoimmune diseases has increased lately. This study aimed to determine the prevalence and patterns of autoantibodies on HEp-2-IIFA according to demographics variables and referring medical specialties.

Methods

A retrospective analysis of the HEp-2-IIFA carried out between January and June of 2017 was performed. The International Consensus on Antinuclear Antibodies Patterns (ICAP) and the Brazilian Consensus on Autoantibodies were used for patterns definition on visual reading of the slides. Anti-cell (AC) codes from ICAP and Brazilian AC codes (BAC) were used for patterns classification.

Results

From 54,990 samples referred for HEp-2-IIF testing, 20.9% were positive at titer ≥ 1/80. HEp-2-IIFA positivity in females and males was 24% and 12%, respectively (p < 0.0001). The proportion of positive results in the 4 age groups analyzed: 0–19, 20–39, 40–59, and ≥ 60 years was 23.3, 20.2, 20.1, and 22.8%, respectively (p < 0.0001). Considering all positive sera (n = 11,478), AC-4 nuclear fine speckled (37.7%), AC-2 nuclear dense fine speckled (21.3%), BAC-3 nuclear quasi-homogeneous (10%) and mixed/composite patterns (8.8%) were the most prevalent patterns. The specialties that most requested HEp-2-IIFA were general practitioner (20.1%), dermatology (15%), gynecology (9.9%), rheumatology (8.5%), and cardiology (5.8%). HEp-2-IIFA positivity was higher in patients referred by rheumatologists (35.7% vs. 19.6%) (p < 0.0001). Moderate (46.4%) and high (10.8%) titers were more observed in patients referred by rheumatologists (p < 0.0001). We observed a high proportion of mixed and cytoplasmic patterns in samples referred by oncologists and a high proportion of BAC-3 (nuclear quasi-homogeneous) pattern in samples referred by pneumologists.

Conclusions

One-fifth of the patients studied were HEp-2-IIFA-positive. The age groups with more positive results were 0–19 and ≥ 60 years. AC-4, AC-2, BAC-3 and mixed/composite patterns were the most frequent patterns observed. Rheumatologists requested only 8.5% of HEp-2-IIFA. Positive results and moderate to high titers of autoantibodies were more frequent in patients referred by rheumatologists.

Prevalence of antinuclear antibodies in inflammatory bowel disease and seroconversion after biological therapy

BACKGROUND

Estimates of detectable antinuclear antibodies (ANA) prevalence vary widely, from 6% in healthy populations to 50-80% in patients with autoimmune disease. However, there is a lack of evidence about the overall prevalence in inflammatory bowel disease (IBD) and ANA seroconversion after the beginning of biological therapy.

OBJECTIVES

The aim of the study was to investigate the overall prevalence of ANA in IBD patients, their relationship with different treatments, clinical outcomes and the seroconversion rate of ANA in patients treated with biological therapy.

METHODS

Ambispective observational study including all consecutive IBD patients was carried out. Information about the presence of ANA, disease phenotype, duration, activity, complications, and past and current treatments were transversally collected. Retrospectively, in patients with detectable ANA, data regarding previous ANA detection and the diagnosis of lupus-like syndrome (LLS) was gathered.

RESULTS

A total of 879 IBD patients were included. We observed a detectable ANA prevalence of 13.6%. The presence of ANA was frequently associated with biological therapy (36/118) and decreased when immunomodulators were combined to this therapy (7/32). Of 78 patients with ANA prior to the beginning of biological therapy, a seroconversion rate of 28.8% was observed after a mean of 3.14 years. Only 1 patient suffered LLS.

CONCLUSION

Our study showed a prevalence of detectable ANA higher than the expected in healthy population. The presence of ANA was lower when immunomodulator therapy is associated. The ANA seroconversion rate is relevant after the initiation of biological treatment nevertheless, the risk of LLS appeared to be marginal.

Antinuclear Antibody Profiling in Patients of a Tertiary Care Centre in Central India

The incidence of autoimmune disorders that includes the connective tissue diseases has seen a rise in India in recent times. Antinuclear antibodies, the telltale sign of systemic autoimmune response, thus can be used as a screening tool and also to support the diagnosis of systemic autoimmune disease. The present retrospective cross- sectional analysis aimed to study the antinuclear antibodies profile (patterns and specific antibody reactivity) amongst suspected cases of auto-immune disorders at a tertiary care teaching hospital. The study retrieved and reviewed reports of 644 patients sent for ANA testing by indirect immunofluorescence assay over a period of 1 year by different specialty departments. Positive samples were further processed for anti-ds-DNA antibody and antibodies to extractable nuclear antigen. Data collected was statistically analysed. ANA pattern positivity was observed in 31% of cases and a positive antibody reactivity was seen in 66% of them. Female predominance (82%) was noted in both pattern positivity and antibody reactivity. High levels of pattern positivity and antibody reactivity was found in the young adults (45.9%). Amongst the ANA patterns, the nuclear homogenous pattern was found the commonest. The common antibodies associated with this pattern were anti-dsDNA and U1 Sm/RNP antibodies. A stronger fluorescence intensity on initial screening showed a higher confirmation rate for specific antibodies on immunoassay. High occurrence of positive ANA patterns in autoimmune disorders suggests its utilization as a screening tool for them and would also play an adjuvant to the diagnosis. Early knowledge about future autoimmunity will earn better prognostic achievements through better treatment interventions.

Antinuclear Autoantibodies in Health: Autoimmunity Is Not a Synonym of Autoimmune Disease

The incidence of autoimmune diseases is increasing. Antinuclear antibody (ANA) testing is a critical tool for their diagnosis. However, ANA prevalence in healthy persons has increased over the last decades, especially among young people. ANA in health occurs in low concentrations, with a prevalence up to 50% in some populations, which demands a cutoff revision. This review deals with the origin and probable physiological or compensatory function of ANA in health, according to the concept of immunological clearance, theory of autoimmune regulation of cell functions, and the concept of functional autoantibodies. Considering ANA titers ≤1:320 as a serological marker of autoimmune diseases seems inappropriate. The role of anti-DFS70/LEDGFp75 autoantibodies is highlighted as a possible anti-risk biomarker for autoimmune rheumatic disorders. ANA prevalence in health is different in various regions due to several underlying causes discussed in the review, all influencing additive combinations according to the concept of the mosaic of autoimmunity. Not only are titers, but also HEp-2 IFA) staining patterns, such as AC-2, important. Accepting autoantibodies as a kind of bioregulator, not only the upper, but also the lower borders of their normal range should be determined; not only their excess, but also a lack of them or "autoimmunodeficiency" could be the reason for disorders.

Autoimmune liver disease-associated serologic profiling in Chinese patients with acute hepatitis E virus infection

The association between hepatitis E virus (HEV) and autoimmune liver diseases has been well-researched; however, the focus has been on autoimmune hepatitis (AIH) and not primary biliary cholangitis (PBC). Therefore, we aimed to investigate the prevalence and evolution of AIH- and PBC-related autoantibodies in Chinese patients with HEV infection. In this retrospective study, 164 patients with acute HEV were included, specifically those whose liver autoantibody results were available and who had no pre-existing liver disease at the time of HEV diagnosis. Positive liver autoimmune serology was present in 69 (42.1%) patients and 21 (12.8%) had at least two autoantibodies at diagnosis. Greater age and alkaline phosphatase levels were independent risk factors for autoantibody positivity. Follow-up serologic tests, which were available for 27 of the 69 autoantibody-positive patients, showed that although antinuclear antibodies disappeared in 11/20 (55.0%) and antimitochondrial antibodies disappeared in 4/5 (80%) patients, 16 still remained positive for autoantibodies and two of them even developed new PBC-related antibodies, as described below. One patient developed a rim-like ANA pattern, accompanied by an enhancement of anti-gp210 positivity; and the other was diagnosed as PBC, based on chronic elevation of cholestatic enzymes and presentation with de novo AMA-M2, 18 months after HEV clearance. In conclusion, AIH- and PBC-related autoantibodies are frequently present during acute HEV infection, indicating that HEV should be excluded before diagnosing AIH and/or PBC. Importantly, some cases maintained or developed autoantibodies after viral clearance, and one patient subsequently developed PBC, highlighting that these individuals warrant long-term follow-up.

Antinuclear antibodies and recurrent miscarriage: Systematic review and meta-analysis

Studies have investigated the relationship between antinuclear antibodies (ANA) and recurrent miscarriage (RM). The objective of this paper is to evaluate the presence of ANA as a risk factor for spontaneous abortion in patients with RM. By considering the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis, the authors performed systematic review and meta-analysis by searching the databases of PubMed/Medline and SCOPUS. Review Manager, Version 5.3 performed the statistical analysis. Binary variables were analyzed by odds ratio (ORs) and 95% confidence interval (CI). The subgroup analysis compared the effect of different ANA titers. The authors analyzed the ANA patterns of immunofluorescence staining. Seven case-control studies were selected. The frequency of positive ANA was statistically higher in the RM group (20.6%, 288/1400) as compared to the control group (6.7%, 72/1080). The meta-analysis of the positive ANA showed a statistical difference between the two groups (OR 3.30, 95% CI 1.41-7.73; I²  = 87%, P = .006). Studies have revealed different frequencies of ANA patterns of immunofluorescence. This meta-analysis suggested that positive ANA might increase the risk of RM. However, it was not possible to conclude which ANA pattern of immunofluorescence staining is more frequent in the RM group.

How to investigate: Suspected systemic rheumatic diseases in patients presenting with muscle complaints

Muscular symptoms, which may be due to multiple causes, are one of the most common early complaints in a rheumatology practice. Musculoskeletal symptoms in rheumatic conditions are very varied, ranging from mechanical problems to muscular symptoms derived from inflammatory and systemic autoimmune diseases. Several drugs commonly used by different specialists and certain drugs used in rheumatology can also cause a wide variety of muscle symptoms. A description of different systemic autoimmune diseases follows to describe the different forms of involvement of the musculoskeletal system that they cause, as well as the main causes with which a differential diagnosis should be made. In this chapter, we will try to give some clues to reach an early diagnosis using clinical criteria, particularly based on a directed anamnesis and physical examination, discussing possible guidelines for the complimentary tests that may be required in patients with muscle complaints.

Autoimmune hepatitis in human immunodeficiency virus-infected patients: A case series and review of the literature

BACKGROUND

Abnormal liver chemistry is a common problem in human immunodeficiency virus (HIV)-infected patients. Common causes of abnormal liver enzymes in this population include viral hepatitis B/C or opportunistic infection, drug toxicity, and neoplasm. Autoimmune hepatitis is a rare cause of hepatitis in HIV-infected individuals; however, this condition has been increasingly reported over the past few years.

CASE SUMMARY

We present 13 HIV-infected patients (5 males and 8 females) who developed autoimmune hepatitis (AIH) after their immune status was restored, i.e. all patients had stable viral suppression with undetectable HIV viral loads, and median CD4+ counts of 557 cells/× 10⁶ L. Eleven patients presented with chronic persistent elevation of aminotransferase enzyme levels. One patient presented with acute hepatitis and the other patient presented with jaundice. The median levels of aspartate aminotransferase and alanine aminotransferase enzymes were 178 and 177 U/mL, respectively. Elevation of immunoglobulin G levels was present in 11 (85%) patients. Antinuclear antibody and anti-smooth muscle antibody were positive in 11 (85%) and 5 (38%) patients. Liver biopsy was performed in all patients. They had histopathological findings compatible with AIH. The patients were started on prednisolone for remission induction, with good response. After improvement of the liver chemistry, the dose of prednisolone was tapered, and azathioprine was added as life-long maintenance therapy. At the last follow-up visit, all were doing well, without HIV viral rebound or infectious complications.

CONCLUSION

This report underscores the emergence of autoimmune hepatitis in the context of HIV infection.

Autoantibodies Associated With Connective Tissue Diseases: What Meaning for Clinicians?

Connective tissue diseases (CTDs) such as systemic lupus erythematosus, systemic sclerosis, myositis, Sjögren's syndrome, and rheumatoid arthritis are systemic diseases which are often associated with a challenge in diagnosis. Autoantibodies (AAbs) can be detected in these diseases and help clinicians in their diagnosis. Actually, pathophysiology of these diseases is associated with the presence of antinuclear antibodies. In the last decades, many new antibodies were discovered, but their implication in pathogenesis of CTDs remains unclear. Furthermore, the classification of these AAbs is nowadays misused, as their targets can be localized outside of the nuclear compartment. Interestingly, in most cases, each antibody is associated with a specific phenotype in CTDs and therefore help in better defining either the disease subtypes or diseases activity and outcome. Because of recent progresses in their detection and in the comprehension of their pathogenesis implication in CTD-associated antibodies, clinicians should pay attention to the presence of these different AAbs to improve patient's management. In this review, we propose to focus on the different phenotypes and features associated with each autoantibody used in clinical practice in those CTDs.