Recognition of rare antinuclear antibody patterns based on a novel attention-based enhancement framework.

Rare antinuclear antibody (ANA) pattern recognition has been a widely applied technology for routine ANA screening in clinical laboratories. In recent years, the application of deep learning methods in recognizing ANA patterns has witnessed remarkable advancements. However, the majority of studies in this field have primarily focused on the classification of the most common ANA patterns, while another subset has concentrated on the detection of mitotic metaphase cells. To date, no prior research has been specifically dedicated to the identification of rare ANA patterns. In the present paper, we introduce a novel attention-based enhancement framework, which was designed for the recognition of rare ANA patterns in ANA-indirect immunofluorescence images. More specifically, we selected the algorithm with the best performance as our target detection network by conducting comparative experiments. We then further developed and enhanced the chosen algorithm through a series of optimizations. Then, attention mechanism was introduced to facilitate neural networks in expediting the learning process, extracting more essential and distinctive features for the target features that belong to the specific patterns. The proposed approach has helped to obtained high precision rate of 86.40%, 82.75% recall, 84.24% F1 score and 84.64% mean average precision for a 9-category rare ANA pattern detection task on our dataset. Finally, we evaluated the potential of the model as medical technologist assistant and observed that the technologist's performance improved after referring to the results of the model prediction. These promising results highlighted its potential as an efficient and reliable tool to assist medical technologists in their clinical practice.

Prevalence and significance of autoantibodies in children with metabolic dysfunction-associated steatotic liver disease: A systematic review and meta-analysis.

Significance of autoantibodies in pediatric metabolic dysfunction-associated steatotic liver disease (MASLD) is unknown. Our aim was to determine the prevalence and significance of autoantibodies in MASLD. PubMed and Scopus were searched and six articles (689 [487 males] MASLD patients) were identified. Antinuclear antibodies (ANA) was positive in 28% (95% confidence interval [CI]: 17%-39%, n = 6 studies), Antismooth muscle antibodies (ASMA) in 28% (95% CI: 8%-50%, n = 5 studies), Actin-positive in 15% (95% CI: 10%-20%, n = 2 studies) and elevated immunoglobulin G in 17% (95% CI: 1%-39%, n = 4 studies). Anti-liver-kidney-microsomal antibody was not present in any patient. There was no significant association of ANA positivity with degree of liver steatosis, liver fibrosis or nonalcoholic fatty liver disease activity score (NAS) but patients with ASMA positivity had advanced fibrosis (pooled risk ratio [RR] 1.77; 95% CI 1.16-2.71) and higher risk of NAS ≥5 (pooled RR 1.21; 95% CI: 1.01-1.44, n = 2 studies, 243 patients). To conclude, non-organ specific autoantibodies are present in over one-fourth of children with MASLD and the presence of ASMA maybe associated with increased disease severity.

Clinical features and visual prognosis of very late-onset neuromyelitis optica spectrum disorder-related optic neuritis.

BACKGROUND: Very late-onset neuromyelitis optica spectrum disorder-related optic neuritis is limited to a few case reports. OBJECTIVE: To investigate the clinical features and visual prognosis of very late-onset neuromyelitis optica spectrum disorder-related optic neuritis. METHODS: This study evaluated 22 patients with first-onset optic neuritis and fulfilled the 2015 diagnosis criteria for neuromyelitis optica spectrum disorders. RESULTS: The mean age at optic neuritis onset was 73.91 ± 4.71 (range: 70-82) years with a female predominance (81.8%; ratio: 4.5:1). Antinuclear antibody seropositivity and seronegativity were identified in 12 (55.5%) and 10 (45.5%) patients, respectively. Severe visual loss persisted in 19 (19/42, 45.3%) eyes at the last follow-up. Although patients with antinuclear antibody seropositivity had a significantly higher frequency of attacks (P = 0.015), but they had a longer median time to reach severe visual loss (37 vs. 26 months; log-rank test, P = 0.023). Multivariate logistic regression analysis revealed antinuclear antibody seropositivity (hazard ratio = 4.849, 95% confidence interval: 1.309-17.965, P = 0.018) as a good predictor of visual acuity improvement. CONCLUSION: Patients with very late-onset neuromyelitis optica spectrum disorder-related optic neuritis may develop severe optic neuritis, and those with antinuclear antibody seronegativity have a similar clinical presentation but worse outcome than those with seropositivity.

Assessing serum anti-nuclear antibodies HEp-2 patterns in synucleinopathies.

This study investigates the presence of antinuclear antibodies (ANA) in three primary synucleinopathies - Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB), compared to healthy controls. Autoinflammatory disorders typically involve the immune system mistakenly attacking the body's own cells and start producing ANA. There is an increasing body of evidence that immune-mediated inflammation is a pathological feature linked to synucleinopathies. To investigate whether this could be autoimmune mediated we analyzed for ANA in the plasma of 25 MSA, 25 PD, and 17 DLB patients, along with 25 healthy controls, using the ANA HEp-2 indirect immunofluorescence antibody assay (ANA HEp-2 IFA). Contrary to initial expectations, results showed ANA HEp-2 positivity in 12% of PD, 8% of MSA patients, 18% of DLB patients, and 17% of healthy controls, indicating no increased prevalence of ANA in synucleinopathies compared to age-matched healthy individuals. Various ANA HEp-2 patterns were identified, but no specific pattern was associated with individual synucleinopathies. We conclude hereby that synucleinopathies are not associated with detectable presence of ANA in plasma.

Systemic Lupus Erythematosus and Cytokine Storm.

Systemic lupus erythematosus (SLE) is the prototype of autoimmune diseases and can manifest with a plethora of clinical signs and symptoms associated with a myriad of laboratory abnormalities. An infrequent but potentially lethal complication of SLE is macrophage activation syndrome (MAS). The diagnosis of MAS in SLE can be very challenging due to similarities in presentation of both flares and infections, such as fever, lymphadenopathy, splenomegaly, and cytopenias. These aggravating factors contribute to the increased risk of poor outcomes in SLE-associated MAS. Indeed, at the moment MAS remains invariably lethal if untreated and still has a high mortality rate with treatment. In this chapter, we discuss several aspects of MAS in the context of SLE and in particular, the pathogenesis of MAS in SLE, how MAS presents in pediatric versus adult SLE, and, finally, MAS treatment in SLE and future directions.

Pediatric Primary Raynaud's Phenomenon: A Comprehensive Cardiovascular Analysis.

Our aim in this study is to evaluate the cardiovascular findings of pediatric patients with primary Raynaud's phenomenon (RP) and to determine if there are any pathological findings. Our study included 42 pediatric patients aged between 7 and 18 who were diagnosed with primary RP and did not have any additional underlying structural vascular disease or secondary rheumatological conditions. The control group consisted of 30 healthy volunteers aged 7-18 years, matched by age and sex, without any additional diseases. We evaluated demographic, clinical, and laboratory findings, echocardiographic and capillaroscopic features, as well as carotid intima-media thickness. Compared to the control group, pediatric patients with primary RP showed increased A wave velocity and E/E' ratio parameters in the left ventricle, indicating diastolic dysfunction of the heart. The isovolumetric relaxation time (IVRT) was prolonged in both the left and right ventricles, and the E/A ratio decreased in the left ventricle. The myocardial performance index (MPI), indicating both systolic and diastolic dysfunction, increased in both ventricles. Additionally, the aortic stiffness index, aortic elastic modulus (Ep), and left carotid intima-media thickness (CIMT) significantly increased, while distensibility decreased in pediatric patients with primary RP compared to the control group. The cardiovascular evaluation of pediatric patients with primary RP revealed that diastolic dysfunction is likely present in both the left and right heart. Additionally, based on the aorta and carotid intima measurements, it is suggested that pediatric patients with primary RP are at risk for developing atherosclerosis.

Antiphospholipid antibodies as potential prognostic indicators of recurrent ischemic stroke.

BACKGROUND: Immunity play a pivotal role in the risk of ischemic stroke, and studies have also shown a relationship between ischemic stroke and autoimmune diseases. In light of this we conducted a prospective cohort study to elucidate the impact of antiphospholipid antibodies (aPLs), antinuclear antibodies (ANA), and anti-extractable nuclear antigen autoantibodies (anti-ENA) on the prognosis of ischemic stroke. METHODS: 245 stroke patients were recruited in this single-center study and followed up with for 3 years. Autoantibodies, including aPLs (ACA, anti-ß2GPI, LA), ANA and anti-ENA were evaluated in recurrent ischemic stroke (RIS) and nonrecurrent ischemic stroke (nonRIS). Stroke severity was judged using the National Institutes of Health Stroke Scale (NIHSS). For preventive treatment, 42 IS patients with positive aPLs + ANA/anti-ENA were randomized 1:1 into a hydroxychloroquine (HCQ) treatment group and a control group, and the prognoses were compared. RESULTS: The positive rate of ACA IgG (p = 0.018), anti-ß2GPI IgG (p = 0.047), LA (p = 0.023), and aPLs + ANA/anti-ENA (p = 0.000) were significantly higher in patients with RIS compared to patients with nonRIS, and aPLs + ANA/anti-ENA (HR2.31, 95 % CI1.02-5.25, p = 0.046) and hypertension (HR2.50, 95 % CI1.17-5.35, p = 0.018) were the independent risk factors of recurrence. There were differences in NIHSS at month 36 between those positive and negative for aPLs + ANA/anti-ENA (p = 0.001, Eta2 = 0.052), anti-ENA (p = 0.016, Eta2 = 0.030), ANA (p = 0.035, Eta2 = 0.022), and LA (p = 0.016, Eta2 = 0.028). Furthermore, the recurrence rate of the HCQ treatment group was lower than that of the control group (p = 0.024). CONCLUSIONS: Co-positivity of aPLs and ANA/anti-ENA is an independent risk factor for RIS. However, HCQ therapy may reduce the recurrence rate of IS for these patients.

The Binding Properties of Antibodies to Z-DNA in the Sera of Normal Healthy Subjects.

Antibodies to DNA are a diverse set of antibodies that bind sites on DNA, a polymeric macromolecule that displays various conformations. In a previous study, we showed that sera of normal healthy subjects (NHS) contain IgG antibodies to Z-DNA, a left-handed helix with a zig-zig backbone. Recent studies have demonstrated the presence of Z-DNA in bacterial biofilms, suggesting a source of this conformation to induce responses. To characterize further antibodies to Z-DNA, we used an ELISA assay with brominated poly(dGdC) as a source of Z-DNA and determined the isotype of these antibodies and their binding properties. Results of these studies indicate that NHS sera contain IgM and IgA as well as IgG anti-Z-DNA antibodies. As shown by the effects of ionic strength in association and dissociation assays, the anti-Z-DNA antibodies bind primarily by electrostatic interactions; this type of binding differs from that of induced anti-Z-DNA antibodies from immunized animals which bind by non-ionic interactions. Furthermore, urea caused dissociation of NHS anti-Z-DNA at molar concentrations much lower than those for the induced antibodies. These studies also showed IgA anti-Z-DNA antibodies in fecal water. Together, these studies demonstrate that antibodies to Z-DNA occur commonly in normal immunity and may arise as a response to Z-DNA of bacterial origin.

Clinical Significance of Antibodies to DFS70 in Immunoinflammatory Rheumatic Diseases.

The relevance of the problem of immunoinflammatory rheumatic diseases (IIRD) for modern medicine is determined by their high prevalence in the population, the difficulty of early diagnosis, the rapid development of disability and poor life prognosis. Recent data on the significance of anti-DFS70 have opened up new possibilities for optimizing the step-by-step diagnosis of IIRD. The detection of these antibodies can help in the interpretation of a positive result for antinuclear antibodies (ANA) by indirect immunofluorescence assay on HEp-2 cells (IIFA-HEp-2) in the absence of autoantibodies specific for IIRD. Detection of anti-DFS70 in antinuclear factor (ANF) seropositive patients without clinical and/or serological markers characteristic of a certain disease from the IIRD group can be considered as a potential marker that excludes this group of diseases.

Hydrolysis of Oligodeoxyribonucleotides on the Microarray Surface and in Solution by Catalytic Anti-DNA Antibodies in Systemic Lupus Erythematosus.

Anti-DNA antibodies are known to be classical serological hallmarks of systemic lupus erythematosus (SLE). In addition to high-affinity antibodies, the autoantibody pool also contains natural catalytic anti-DNA antibodies that recognize and hydrolyze DNA. However, the specificity of such antibodies is uncertain. In addition, DNA binding to a surface such as the cell membrane, can also affect its recognition by antibodies. Here, we analyzed the hydrolysis of short oligodeoxyribonucleotides (ODNs) immobilized on the microarray surface and in solution by catalytic anti-DNA antibodies from SLE patients. It has been shown that IgG antibodies from SLE patients hydrolyze ODNs more effectively both in solution and on the surface, compared to IgG from healthy individuals. The data obtained indicate a more efficient hydrolysis of ODNs in solution than immobilized ODNs on the surface. In addition, differences in the specificity of recognition and hydrolysis of certain ODNs by anti-DNA antibodies were revealed, indicating the formation of autoantibodies to specific DNA motifs in SLE. The data obtained expand our understanding of the role of anti-DNA antibodies in SLE. Differences in the recognition and hydrolysis of surface-tethered and dissolved ODNs need to be considered in DNA microarray applications.

Clinical significance of antinuclear antibodies in primary immune thrombocytopenia.

There are discrepancies across guidelines about whether the dosage of antinuclear antibodies (ANAs) is of use at the diagnosis of primary immune thrombocytopenia (ITP). This review describes the current knowledge about ANA prevalence in patients with primary ITP, and their potential usefulness as biomarkers for ITP evolution, response to treatments and increased risk of subsequent development of systemic lupus and thrombosis.

Antinuclear antibodies in childhood immune thrombocytopaenia: An increased risk for development of autoimmune disorders?

Antinuclear antibodies (ANA) have been detected in children with primary immune thrombocytopaenia (ITP), but the effect of ANA titres on clinical outcomes is unclear. Liu et al. retrospectively analysed a cohort of 324 children with primary ITP with a median follow-up time of 25 months and found that patients with high-ANA titres (≥1:160) had lower platelet counts at the onset with a higher subsequent platelet count recovery rate, and additionally were at an increased risk to develop autoimmune disease. These data highlight the possible predictive potential of ANA titres with respect to platelet counts and the development of autoimmunity in children with primary ITP. Commentary on: Liu, et al. The effect of antinuclear antibody titre and its variation on outcomes in children with primary immune thrombocytopaenia. Br J Haematol 2023;202:412-421.

The value of anti-rods and rings antibodies in Chinese population of Dalian City: A retrospective study.

The study aimed to investigate the clinical significance of anti-rods and rings (anti-RR) antibodies in antinuclear antibodies (ANAs) test samples retrospectively. The laboratory data and clinical details of patients with positive anti-RR antibodies were collected and analysed between December 2017 and May 2022 in the First Affiliated Hospital of Dalian Medical University. A total of 72 665 patients were tested for ANAs. There were 45 632 patients discovered with positive ANAs (62.80%), only 131 patients presented with anti-RR antibodies (0.18%), among which only 68 patients were hospitalized patients with a definitive diagnosis. Among the 68 patients with a definitive diagnosis, 8 of 68 (11.8%) had autoimmune diseases, and 19 of 68 (27.9%) had renal diseases. Other diseases included liver disease, pulmonary disease, cerebral ischemia, cerebral infarction, chronic cardiac failure and venous thromboembolism. The detection rate of high titre(≥1:1000) anti-RR antibodies is significantly higher in autoimmune diseases.

Mild-to-moderate COVID-19 does not predispose to the development of autoimmune rheumatic diseases or autoimmune-based thrombosis.

An infection with severe acute respiratory syndrome coronavirus (SARS-CoV-2) may have a significant impact on the human immune system. Interactions between the virus and defence mechanisms may promote the development of autoimmune processes which manifest as antinuclear antibody (ANA) synthesis. Since many different viruses are suspected to take part in the pathogenesis of different systemic autoimmune rheumatic diseases (SARDs), we examined whether coronavirus disease 2019 convalescents who suffer from mild to moderate disease have a higher risk of developing ANA and anti-ß2-glicoprotein I IgG antibodies (ß2 GPI). In a retrospective study, we examined 294 adults among volunteer blood donors divided into convalescents (N = 215) and healthy controls (N = 79). For ANA detection, we used line-blotting, a type of indirect immunofluorescence assay (IF), to determine antigenic specificity and ELISA for ß2 GPI. We found a lower incidence of ANA in convalescents than in healthy controls, with the majority of these antibodies directed to antigens with no known clinical significance. Additionally, no participants were positive for ß2 GPI in either group. Our results show that COVID-19 with mild to moderate symptoms in the generally healthy population does not induce the development of ANA or anti-ß2 GPI antibodies for at least 6 months following the disease.

Analytical aspects of the antinuclear antibody test by HEp-2 indirect immunofluorescence: EFLM report on an international survey.

OBJECTIVES: Detection of antinuclear antibodies (ANA) by indirect immunofluorescence assay using HEp-2 cells (HEp-2 IFA) is used to screen for various autoimmune diseases. HEp-2 IFA suffers from variability, which hampers harmonization. METHODS: A questionnaire was developed to collect information on HEp-2 IFA methodology, computer-assisted diagnosis (CAD) systems, training, inter-observer variability, quality assessment, reagent lot change control, and method verification. The questionnaire was distributed to laboratories by Sciensano (Belgium), national EASI groups (Italy, Croatia, Portugal, Estonia, Greece) and ICAP (worldwide). Answers were obtained by 414 laboratories. The results were analysed in the framework of the recent EFLM/EASI/ICAP ANA recommendations (companion paper). RESULTS: Laboratories used either HEp-2, HEp-2000, or HEp-20-10 cells and most laboratories (80%) applied the same screening dilution for children and adults. The conjugate used varied between laboratories [IgG-specific (in 57% of laboratories) vs. polyvalent]. Sixty-nine percent of CAD users reviewed the automatic nuclear pattern and 53% of CAD users did not fully exploit the fluorescence intensity for quality assurance. Internal quality control was performed by 96% of the laboratories, in 52% of the laboratories only with strongly positive samples. Interobserver variation was controlled by 79% of the laboratories. Limited lot-to-lot evaluation was performed by 68% of the laboratories. Method verification was done by 80% of the respondents. CONCLUSIONS: Even though many laboratories embrace high-quality HEp-2 IFA, substantial differences in how HEp-2 IFA is performed and controlled remain. Acting according to the EFLM/EASI/ICAP ANA recommendations can improve the global performance and quality of HEp-2 IFA and nurture harmonization.

Detection of antinuclear antibodies: recommendations from EFLM, EASI and ICAP.

OBJECTIVES: Antinuclear antibodies (ANA) are important for the diagnosis of various autoimmune diseases. ANA are usually detected by indirect immunofluorescence assay (IFA) using HEp-2 cells (HEp-2 IFA). There are many variables influencing HEp-2 IFA results, such as subjective visual reading, serum screening dilution, substrate manufacturing, microscope components and conjugate. Newer developments on ANA testing that offer novel features adopted by some clinical laboratories include automated computer-assisted diagnosis (CAD) systems and solid phase assays (SPA). METHODS: A group of experts reviewed current literature and established recommendations on methodological aspects of ANA testing. This process was supported by a two round Delphi exercise. International expert groups that participated in this initiative included (i) the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group "Autoimmunity Testing"; (ii) the European Autoimmune Standardization Initiative (EASI); and (iii) the International Consensus on ANA Patterns (ICAP). RESULTS: In total, 35 recommendations/statements related to (i) ANA testing and reporting by HEp-2 IFA; (ii) HEp-2 IFA methodological aspects including substrate/conjugate selection and the application of CAD systems; (iii) quality assurance; (iv) HEp-2 IFA validation/verification approaches and (v) SPA were formulated. Globally, 95% of all submitted scores in the final Delphi round were above 6 (moderately agree, agree or strongly agree) and 85% above 7 (agree and strongly agree), indicating strong international support for the proposed recommendations. CONCLUSIONS: These recommendations are an important step to achieve high quality ANA testing.

Comparison of ANA testing by indirect immunofluorescence or solid-phase assays in a low pre-test probability population for systemic autoimmune disease: the Camargo Cohort.

OBJECTIVES: Autoantibodies and, specifically antinuclear antibodies (ANA), are the hallmark of systemic autoimmune diseases (AID). In the last decades, there has been great technical development to detect these autoantibodies along with an increased request for this test by clinicians, while the overall pre-test probability has decreased. In this study, we compare the diagnostic performance of three different methods for ANA screening (indirect immunofluorescence [IIF], addressable laser bead immunoassay [ALBIA], and fluorescence enzyme immunoassay [FEIA]). METHODS: Serum samples at baseline visit from 2,997 participants from the Camargo Cohort, a population with an overall low pre-test probability for systemic AID, were analyzed with the three methods. Participants have a minimum follow-up of 10 years and the development of autoimmune diseases was collected from clinical records. RESULTS: The highest frequency of positive ANA was observed by IIF assay. However, ALBIA showed high sensitivity for AID. Likewise, solid phase assays (SPA) presented higher specificity than IIF for AID. ANA prevalence with any method was significantly higher in females and overall increased with age. Triple positivity for ANA was significantly related to the presence of anti-dsDNA-SSA/Ro60, Ro52, SSB/La, RNP, Scl-70, and centromere-specificities. No association was found for anti-Sm - RNP68, or ribosomal P - specificities. Noteworthy, triple positivity for ANA screening was associated with diagnosis of systemic AID both at baseline visit and follow-up. CONCLUSIONS: ANA detection by IIF may be better when the pre-test probability is high, whereas SPA techniques are more useful in populations with an overall low pre-test probability for systemic AID.

An apoptosis-dependent checkpoint for autoimmunity in memory B and plasma cells.

B lymphocytes acquire self-reactivity as an unavoidable byproduct of antibody gene diversification in the bone marrow and in germinal centers (GCs). Autoreactive B cells emerging from the bone marrow are silenced in a series of well-defined checkpoints, but less is known about how self-reactivity that develops by somatic mutation in GCs is controlled. Here, we report the existence of an apoptosis-dependent tolerance checkpoint in post-GC B cells. Whereas defective GC B cell apoptosis has no measurable effect on autoantibody development, disruption of post-GC apoptosis results in accumulation of autoreactive memory B cells and plasma cells, antinuclear antibody production, and autoimmunity. The data presented shed light on mechanisms that regulate immune tolerance and the development of autoantibodies.

[Practicable diagnostics of Sjögren's syndrome in interstitial lung disease-A discussion article]. / Praktikable Sjögren-Diagnostik bei interstitieller Lungenerkrankung ­ ein Diskussionsbeitrag.

Sjögren's syndrome (SjS) is a possible autoimmune cause of interstitial lung disease. The diagnostic pathway for SjS, however, is largely undefined in comparison to other systemic autoimmune diseases. Subjective sicca symptoms, anti-SS-A/Ro antibodies and even ANA as screening tests all have relevant limitations in sensitivity and/or specificity. Against this background, in an interdisciplinary discussion we have developed a consensus for the clarification of SjS, which is presented here for broader discussion. In addition to ANA and anti-SS-A/Ro antibodies, antibodies against alpha-fodrin should be included. Objective measures of dryness, such a Schirmer and Saxon tests are important, as is a salivary gland biopsy in the absence of typical autoantibodies.

CONSIDERATIONS FOR INTRADERMAL APPLICATION OF IMMUNIZATION WITH NATIVE AUTOLEUKOCYTES IN MEDICINE.

OBJECTIVE: The aim: Analyzing literature sources, to assess possibilities of using the method of intradermal immunization with native autoleukocytes to treat different diseases, to investigate the areas of usage, efficacy and expediency of the technique in clinical practice. PATIENTS AND METHODS: Materials and methods: Analysis of literature sources associated with intradermal immunization with native autoleukocytes. CONCLUSION: Conclusions: The possibilities of using the method of intradermal immunization with native autoleukocytes in the treatment of various diseases are consid¬ered in the literature review. Intradermal immunization with autoleukocytes is one of the methods of personalized medicine. The application of the method results in normalization of the immune system condition as well as suppression of autoimmune and inflammatory processes. It also reduces the synthesis of pro-inflammatory cytokines and strengthens cellular antiviral immunity in a number of viral infections. It is proved, in particular, that the method reduces the synthesis of cryoglobulins, the formation of antithyroid antibodies, normalizes the level of tumor necrosis factor alpha, as well as reduces extrahepatic manifestations of chronic hepatitis and increases the effectiveness of antiviral therapy in patients with viral hepatitis B. Considering that immunization with native autoleukocytes has no contraindications, it can be used in many diseases.