Anti‐nuclear autoantibodies: clinical utility for diagnosis, prognosis, monitoring, and planning of treatment strategy in systemic immunoinflammatory diseases

Harmonization of ANA testing challenge: quantification strategy to accurately predict end-point titers avoiding serial dilution

Despite the advantages of automated systems for antinuclear antibody (ANA) analysis, the prediction of end-point titers avoiding serial dilutions is still in progress. The aims of this study were to set a conversion table providing discriminant ranges of fluorescence signal intensity values (FI) corresponding to the end-point titers and validate this tool in a real-life laboratory setting. Eight hundred ninety-four serum samples were analyzed for ANA using Image Navigator System. In order to classify FI into non-overlapping groups corresponding to conventional end-point titers, statistical discriminant analysis was used. Validation study was performed calculating agreement and error rates between visual readings and conversion table of 1119 routine ANA positive samples. Setting of FI ranges corresponding to the end-point titers for different staining patterns was computed. For samples showing single pattern, the overall agreement between visual readings and conversion table was 98.4% for all titers ranging from 1:160 to 1:2560, of which 68.0% had the same titer and 30.4% were within ± one titer difference. Concordance rates according to ANA patterns were as follows: (1) nuclear 98.4%, of which 67.0% had the same titer and 31.4% ± one titer; (2) cytoplasmic 100%, of which 72.7% had the same titer and 27.3% than ± one titer; (3) mitotic 66.6%, of which 33.3% had more ± one titer. Our study developed a quantification method for autoantibodies titers assessment based on just one single sample dilution instead of traditional serial dilution approach, providing significant advantages in routine laboratory in terms of reduction in hand-on time and harmonization of results.

Deep Active Learning for Automatic Mitotic Cell Detection on HEp-2 Specimen Medical Images

Identifying Human Epithelial Type 2 (HEp-2) mitotic cells is a crucial procedure in anti-nuclear antibodies (ANAs) testing, which is the standard protocol for detecting connective tissue diseases (CTD). Due to the low throughput and labor-subjectivity of the ANAs' manual screening test, there is a need to develop a reliable HEp-2 computer-aided diagnosis (CAD) system. The automatic detection of mitotic cells from the microscopic HEp-2 specimen images is an essential step to support the diagnosis process and enhance the throughput of this test. This work proposes a deep active learning (DAL) approach to overcoming the cell labeling challenge. Moreover, deep learning detectors are tailored to automatically identify the mitotic cells directly in the entire microscopic HEp-2 specimen images, avoiding the segmentation step. The proposed framework is validated using the I3A Task-2 dataset over 5-fold cross-validation trials. Using the YOLO predictor, promising mitotic cell prediction results are achieved with an average of 90.011% recall, 88.307% precision, and 81.531% mAP. Whereas, average scores of 86.986% recall, 85.282% precision, and 78.506% mAP are obtained using the Faster R-CNN predictor. Employing the DAL method over four labeling rounds effectively enhances the accuracy of the data annotation, and hence, improves the prediction performance. The proposed framework could be practically applicable to support medical personnel in making rapid and accurate decisions about the mitotic cells' existence.

Autoantibodies in Rheumatoid Arthritis - Laboratory and Clinical Perspectives

Measurement of two groups of autoantibodies, rheumatoid factor (RF) and anti-citrullinated protein/peptide antibodies (ACPA) have gained increasing significance in the diagnosis and classification of rheumatoid arthritis (RA) over the last 65 years. Despite this rising importance of autoimmune serology in RA, there is a palpable lack of harmonization between different commercial RF and ACPA tests. While a minimal diagnostic specificity has been defined for RF tests, which almost always are related to an international reference preparation, neither of this applies to ACPA. Especially assays with low diagnostic specificity are associated with very low positive predictive values or post-test probabilities in real world settings. In this review we focus on issues of practical bearing for the clinical physician diagnosing patients who potentially have RA, or treating patients diagnosed with RA. We advocate that all clinically used assays for RF and ACPA should be aligned to a common diagnostic specificity of 98-99% compared to healthy controls. This high and rather narrow interval corresponds to the diagnostic specificity seen for many commercial ACPA tests, and represents a specificity that is higher than what is customary for most RF assays. Data on antibody occurrence harmonized in this way should be accompanied by test result-specific likelihood ratios for the target diagnosis RA on an ordinal or interval scale, which will provide the clinical physician with more granular and richer information than merely relating numerical values to a single cut-off point. As many physicians today are used to evaluate autoantibodies as positive or negative on a nominal scale, the introduction of test result-specific likelihood ratios will require a change in clinical mindset. We also discuss the use of autoantibodies to prognosticate future arthritis development in at-risk patients as well as predict severe disease course and outcome of pharmacological treatment.

Uncommon patterns of antinuclear antibodies recognizing mitotic spindle apparatus antigens and clinical associations

Antinuclear antibodies (ANA) are key biomarkers in the evaluation of rheumatic diseases. The prevalence and clinical significance of uncommon or rare patterns, particularly those directed at the mitotic spindle apparatus (MSA), are not well understood. We aimed to investigate the prevalence and clinical significance of anti-MSA patterns in a Colombian population.During 2013 and 2014, 113,491 consecutive determinations of ANA were studied for the presence of uncommon patterns. Clinical and laboratory data of anti-MSA positive patients were retrospectively collected and analyzed.Of the 113,491 patients tested, 60,501 (53%) were positive for ANA, of which 834 (1.3%) were positive for uncommon/rare patterns of ANA (anti-MSA in 592 cases). Of these 592 cases, complete data were available in 329 patients, of whom 116 had an established diagnosis. Anti-MSA antibodies were the only ANA positive test in 81% patients. At least one fine reactivity was identified in 19/116 (16.3%) of ANA-positive patients, of which anti-Ro was the most prevalent (18/116, 15.5%).The most frequent patterns were nuclear mitotic apparatus (NuMA) (56%) and MSA-2 (25%). The NuMA pattern had the highest ANA titers: mean 320 (range 80-2560) and behaved as monospecific antibodies. The most frequent systemic autoimmune diseases were Sjögren syndrome (SS) (18.1%), rheumatoid arthritis (RA) (13.8%), and systemic lupus erythematosus (SLE) (11%). Undifferentiated connective tissue disease (UCTD) was associated with the centrosome (P < .001), NuMA (P < .02) and MSA-2 (P < .45) patterns. Chronic idiopathic urticaria (CIU) was associated with the NuMA pattern (P < .02) and sensorineural hearing loss (SNHL) was associated with the MSA-2 (P < .001), centrosome (P < .68) and CENP-F (P < .38) patterns, previously unreported findings. Malignancies were found in 8 patients (50% were papillary thyroid cancer).In a large cohort of ANA determinations, uncommon patterns were found in around 1% of cases. The most frequent anti-MSA patterns found were NuMA and MSA-2. More than 50% of patients with anti-MSA had an associated CTD, mainly SS, RA and SLE, and anti-MSA behaved as monospecific antibodies. Other entities of presumed autoimmune origin, like CIU and SNHL, might be associated with these patterns.

Automated Processing and Evaluation of Anti-Nuclear Antibody Indirect Immunofluorescence Testing

Indirect immunofluorescence (IIF) is considered by the American College of Rheumatology (ACR) and the international consensus on ANA patterns (ICAP) the gold standard for the screening of anti-nuclear antibodies (ANA). As conventional IIF is labor intensive, time-consuming, subjective, and poorly standardized, there have been ongoing efforts to improve the standardization of reagents and to develop automated platforms for assay incubation, microscopy, and evaluation. In this study, the workflow and performance characteristics of a fully automated ANA IIF system (Sprinter XL, EUROPattern Suite, IFA 40: HEp-20-10 cells) were compared to a manual approach using visual microscopy with a filter device for single-well titration and to technologist reading. The Sprinter/EUROPattern system enabled the processing of large daily workload cohorts in less than 8 h and the reduction of labor hands-on time by more than 4 h. Regarding the discrimination of positive from negative samples, the overall agreement of the EUROPattern software with technologist reading was higher (95.6%) than when compared to the current method (89.4%). Moreover, the software was consistent with technologist reading in 80.6–97.5% of patterns and 71.0–93.8% of titers. In conclusion, the Sprinter/EUROPattern system provides substantial labor savings and good concordance with technologist ANA IIF microscopy, thus increasing standardization, laboratory efficiency, and removing subjectivity.

Automated antinuclear immunofluorescence antibody analysis is a reliable approach in routine clinical laboratories

Background:

Indirect immunofluorescence (IIF) assays are recommended as the gold standard method for the detection of antinuclear antibodies (ANAs). This study aimed to investigate the reliability of an automated system.

Methods:

We compared 3745 serum samples using NOVA View archived images with manual analysis via microscopy. A custom cutoff value was established to distinguish ANA titers and was validated in two clinical laboratories. The automatic ANA pattern recognition system was evaluated, and all ANA-positive sera were subjected to two commercial ANA IIF kits to compare the consistency of the pattern interpretation results. For inconsistent patterns, a third ANA IIF testing kit was utilized.

Results:

Agreement of the interpretation of the ANA IIF test using the platform of NOVA View and manual microscopy was 96.9%. The local cutoff value to discriminate ANA titers in four main ANA patterns was calculated based on 1390 serum samples. In our laboratory, the titer prediction accuracy was superior to the preset cutoff in NOVA View (p<0.01); the performance was similar in another laboratory (p=0.11). The automatic pattern recognition accuracies of speckled, homogeneous, centromere, nucleolar and nuclear dot patterns were 62.7%, 57.4%, 92.6%, 30.5% and 27.3%, respectively. The consistency of the pattern interpretation results between INOVA and MBL kits was 95.3%.

Conclusions:

It is necessary to establish a custom value-added ANA report. However, confirmation of the digital immunofluorescence images by expert technicians was essential, and suspect results of an ANA pattern should be reconfirmed by another commercial ANA IIF kit to achieve more reliable results.

European Attempts to Set Guidelines for Improving Diagnostics of Autoimmune Rheumatic Disorders

The rational way to set a diagnosis and estimate a prognosis in rheumatology is to start by setting a tentative diagnosis and then follow a fixed scheme for laboratory testing, eg, by using an agreed algorithm. The use of order algorithms can be extended to post-test algorithms that will assist clinicians in approaching the right diagnosis and prognosis. New methods used in autoimmune serology do not deliver results that can be directly compared to those of older methods, and thus the new methods need to be thoroughly tested with sera from differential diagnostically relevant disease controls to set a clinically meaningful cut-off for positivity. Borderline positive results need to be treated with special care to avoid misuse. Early diagnosis is of great importance, and serological results can be very useful if used the right way. European efforts to secure rational diagnostic work-up in autoimmune rheumatic disease have led to a better dialogue between clinicians and laboratory scientists in several countries.

Autoantibody Detection Using Multiplex Technologies

Measurement of multiple antibodies has been possible for years using labor-intensive methods such as counterimmunoelectrophoresis and radioimmunoprecipitation. Recently, simpler methods that are more practical for routine analysis, often described as multiplex technologies, have been introduced. One common technique, the line assay, uses nitrocellulose strips that are precoated at different locations with more than a dozen recombinant proteins or peptides. Detection of results may be performed visually or with scanning instrumentation. A second technique uses families of polystyrene beads that are dyed to establish a unique identity; each bead type is then coated with a specific affinity-purified or recombinant protein. Detection is performed by flow cytometry. There have been multiple descriptions of the use of these techniques for measuring antibodies associated with the antinuclear antibody screen. More recent reports describe applications to antibodies associated with hypothyroidism, ANCA, anti-phospholipid syndrome, and celiac disease. This review summarizes the work that has been performed to date and examines the potential benefits of multiplexing to both the laboratory and the physician.

Biosensor for total antinuclear antibody determination at the point-of-care

Antinuclear antibodies (ANA) are important in diagnosis and follow-up of patients with autoimmune conditions. The current increase in ANA requests is driven by broadening the use of ANA from a test for lupus to a test for diverse autoimmune diseases, but the standard method is protracted, cumbersome and prone to error. We describe an electrochemical method for quantifying total ANA for use as a point-of-care diagnostic aid. In this technology the target autoantigens are derived from a protein/nucleoprotein mixture prepared from an inexpensive source and adsorbed to a porous membrane with high protein binding capacity. Serum is slowly drawn through the membrane comprising the high density autoantigen mixture to induce rapid binding of patient autoantibodies. After rinsing, peroxidase-conjugated anti-IgG is drawn through the membrane followed by rinsing, insertion of an electrode assembly, and addition of the enzyme substrate. Substrate peroxidation is measured by microamperage-level current accompanying electrochemical reduction of the intermediate product. Values are comparable to a standard ANA test but require a total processing time of ~20min. This method has the promise to greatly expand ANA testing in clinical settings for initial patient assessment of autoimmune disease.

Anti-nuclear antibody detection in cryoprecipitates: distinctive patterns in hepatitis C virus-infected patients

BACKGROUND

Anti-nuclear antibodies are immunoglobulins directed against nuclear antigens. They are associated with many autoimmune disorders, but are frequently found in patients infected with hepatitis C virus, possibly indicating an underlying common origin. Likewise, mixed cryoglobulinemia often accompanies autoimmune diseases and hepatitis C infection.

AIM

To compare anti-nuclear antibodies and immunoglobulin content of cryoprecipitates from hepatitis C virus-positive patients in order to assess their predictive value in the onset of hepatitis C virus-driven extrahepatic disorders.

METHODS

Serum from 40 hepatitis C virus-positive patients and 50 controls with rheumatoid arthritis was processed for cryoglobulin detection: all subjects presented with Type III mixed cryoglobulinemia. Immunoglobulin content and immunoglobulin subclasses of cryoprecipitates were assessed by immunofixation and tested by ELISA for rheumatoid factor. Cryoprecipitates were also analysed for anti-nuclear antibodies by indirect immuno-fluorescence to identify specific patterns typical of each condition.

RESULTS

Anti-nuclear antibody patterns differed significantly; 26 infected subjects (65%) were IgG3 positive: of these, 25 were also anti-nuclear antibody-positive (96.1%).

CONCLUSIONS

IgG3 are autoreactive clones unrelated to viral recognition and possibly involved in autoimmune disorders. Altogether, these results may represent useful diagnostic device for early detection of hepatitis C virus-induced autoimmune diseases.

Clinical and serological features of patients referred through a rheumatology triage system because of positive antinuclear antibodies

Background

The referral of patients with positive anti-nuclear antibody (ANA) tests has been criticized as an inappropriate use of medical resources. The utility of a positive ANA test in a central triage (CT) system was studied by determining the autoantibody profiles and clinical diagnoses of patients referred to rheumatologists through a CT system because of a positive ANA test.

Methods

Patients that met three criteria were included: (1) referred to Rheumatology CT over a three year interval; (2) reason for referral was a “positive ANA”; (3) were evaluated by a certified rheumatologist. The CT clinical database was used to obtain demographic and clinical information and a serological database was used to retrieve specific ANA and/or extractable nuclear antigen (ENA) test results. Clinical information was extracted from the consulting rheumatologist's report.

Results

15,357 patients were referred through the CT system; 643 (4.1%) of these because of a positive ANA and of these 263 (40.9%) were evaluated by a certified rheumatologist. In 63/263 (24%) of ANA positive patients, the specialist provided a diagnosis of an ANA associated rheumatic disease (AARD) while 69 (26.2%) had no evidence of any disease; 102 (38.8%) had other rheumatologic diagnoses and 29 (11%) had conditions that did not meet AARD classification criteria. Of ANA positive archived sera, 15.1% were anti-DFS70 positive and 91.2% of these did not have an AARD.

Conclusions

This is the first study to evaluate the serological and clinical features of patients referred through a CT system because of a positive ANA. The spectrum of autoantibody specificities was wide with anti-Ro52/TRIM21 being the most common autoantibody detected. Approximately 15% of referrals had only antibodies to DFS70, the vast majority of which did not have clinical evidence for an AARD. These findings provide insight into the utility of autoantibody testing in a CT system.

Evaluation of an automated chemiluminescent immunoassay kit for antinuclear antibodies in autoimmune diseases

The identification of antinuclear antibodies (ANA) is an essential step in the diagnosis of different autoimmune diseases. The gold standard method for their detection is immunofluorescence assay. However, this is a subjective and laborious method, thus a need for simplified objective methods has aroused. In the current work, we evaluated such automated method, the LIAISON(®) (DiaSorin, Italy) for the detection of ANA. A total of 242 sera were analyzed including 67 from healthy subjects, 107 from primary biliary cirrhosis (PBC) patients, 20 from scleroderma patients and 48 from patients with Sjögren's syndrome. All sera were analyzed using the automated chemiluminescent immunoassays, LIAISON(®) for the presence of ANA (kit No. 310300). Positive samples were further analyzed for the presence of antidouble-stranded DNA (dsDNA) and autoantibodies to 6 extractable nuclear antigens (ENA) of the LIAISON(®) (kits No. 310330 and 310331). Negative samples were further analyzed by Blueblot ANA assay (D-TEK, Belgium) or BlueDot Liver (D-TEK, Belgium) as appropriate. The LIAISON(®) specificity for ANA screening was 97%. ANA positivity was determined in 80% of all patients. The sensitivity was 95.5% in scleroderma, 83% in PBC and 72.9% in Sjogren's syndrome. ENA was positive in all ANA-positive scleroderma and Sjögren's sera and in 27% of ANA-positive PBC sera. Among scleroderma or Sjögren patients that were ANA negative, 4 samples were positive for anti-SSA and 2 for RNP-68 utilizing Blueblot assays. M2 protein was found in 1 out of the ANA-negative PBC patients. The LIAISON(®) ANA screen is specific and sensitive for the evaluation of ANA in patients with primary biliary cirrhosis, scleroderma and Sjögren's syndrome.

Delineating the synovial fluid proteome: recent advancements and ongoing challenges in biomarker research

There is an urgent need for identifying novel serum biomarkers that can be used to improve diagnosis, predict disease progression or response to therapy, or serve as therapeutic targets for rheumatic diseases. Synovial fluid (SF) is secreted by and remains in direct contact with the synovial membrane, and can reflect the biochemical state of the joint under different physiological and pathological conditions. Therefore, SF is regarded as an excellent source for identifying biomarkers of rheumatologic diseases. The use of high-throughput and/or quantitative proteomics and sophisticated computational software applied to analyze the protein content of SF has been well-adopted as an approach to finding novel arthritis biomarkers. This review will focus on some of the potential pitfalls of biomarker studies using SF, summarize the status of the field of SF proteomics in general, as well as discuss some of the most promising biomarker study approaches using proteomics. A brief status of the biomarker discovery efforts in rheumatoid arthritis, osteoarthritis and juvenile idiopathic arthritis is also provided.

'There and back again': revisiting the pathophysiological roles of human endogenous retroviruses in the post-genomic era

Almost 8% of the human genome comprises endogenous retroviruses (ERVs). While they have been shown to cause specific pathologies in animals, such as cancer, their association with disease in humans remains controversial. The limited evidence is partly due to the physical and bioethical restrictions surrounding the study of transposons in humans, coupled with the major experimental and bioinformatics challenges surrounding the association of ERVs with disease in general. Two biotechnological landmarks of the past decade provide us with unprecedented research artillery: (i) the ultra-fine sequencing of the human genome and (ii) the emergence of high-throughput sequencing technologies. Here, we critically assemble research about potential pathologies of ERVs in humans. We argue that the time is right to revisit the long-standing questions of human ERV pathogenesis within a robust and carefully structured framework that makes full use of genomic sequence data. We also pose two thought-provoking research questions on potential pathophysiological roles of ERVs with respect to immune escape and regulation.

An evaluation of autoimmune antibody testing patterns in a Canadian health region and an evaluation of a laboratory algorithm aimed at reducing unnecessary testing

Autoantibody tests are often ordered inappropriately. We aimed to evaluate the ordering patterns of these tests in our local health region and to develop a laboratory algorithm aimed at reducing unnecessary tests. Laboratory data including the number and sequence of tests, ordering physician specialties and results for antinuclear (ANA), extractable nuclear antigen (ENA) and anti-double stranded DNA (anti-dsDNA) antibody tests from 2007 to 2009 were evaluated. Based on this information and a clinical consensus meeting, an algorithm was developed and applied retrospectively to 1 year of inpatient laboratory data to simulate potential cost savings. We identified a large volume of these autoantibody tests performed, equating to testing costs of $862,706.72, where less than 17 % of each were positive. Repeated ANA tests were mostly ordered after a previously negative result, and 1 % of patients with negative results changed to ≥1:160 on repeat testing. Close to half of all ENA and anti-dsDNA tests that were ordered were done so simultaneously with ANA, suggesting their use as screening tests. This was done more frequently in the inpatient setting. An algorithm was developed where ENA and anti-dsDNA tests would be cancelled if ANA was negative in the same sample. ANA repeated within 1 year would be cancelled and the prior result provided. Application of the algorithm retrospectively simulated a 30 % cost savings. Repeat testing and simultaneous ordering of multiple tests contributed to the excessive ordering of autoantibody tests in our health region. Our proposed algorithm would reduce testing costs and should be accompanied by appropriate educational information for physicians.

[Prevalence and diagnostic value of antinuclear antibodies without identified antigenic target: a retrospective study of 90 patients]

PURPOSE

The objective of this study was to determine the clinical relevance and the diagnostic significance of positive antinuclear antibodies (ANA) without identified antigenic target by the usual characterization technique.

PATIENTS AND METHODS

Retrospective study conducted in the Laboratory of Immunology of Habib Bourguiba Hospital (Sfax, Tunisia) during 18 months. The inclusion criteria were the presence of an ANA titer greater or equal to 1/320 with negative characterization result. ANA screening was performed by indirect immunofluorescence (IIF) on Hep2 cells. Each positive serum was tested by IIF on Crithidia luciliae (anti-native DNA) and by immunodot (anti-nucleosome, anti-histone, anti-Sm, anti-RNP, anti-SSA, anti-SSB, anti-Scl 70, anti-PM-Scl, anti-Jo1, anti-PCNA and anti-ribosomal protein). Sera of systemic lupus erythematosus (SLE), myositis, and scleroderma patients were tested for anti-Ku, anti-PL7, anti-PL12 and anti-Ro-52 using dot myositis.

RESULTS

Sera of 90 patients were studied: 18 men and 72 women (average age: 44 years). Drug-induced ANA was found in eight patients. The most frequent clinical symptoms were joint (56.7%), cutaneous (54.4%) and constitutional symptoms (45.6%). The diagnosis of an autoimmune disease was suspected in 49 patients (54.5%) and confirmed in 30 (33.3%) including 20 cases of connective tissue disease: myositis (n=6), scleroderma (n=5), Sjögren's syndrome (n=3), SLE (n=4), rheumatoid arthritis (n=6) and antiphospholipid syndrome (n=4). Other autoimmune diseases were less frequent. The anti-Ku antibody was detected in the majority of patients with connective tissue disease. The diagnosis of non-autoimmune diseases was established in 25.5% of patients. Eighteen patients (20%) had no diagnosis orientation.

CONCLUSION

Our study demonstrated the diagnostic value of the presence of ANA even in the absence of known antigenic target, confirmed the role of the IIF as "gold standard" test for ANA screening, and suggested the usefulness of the addition of Ku antigen in the immunodot classic profile.

Missing links in high quality diagnostics of inflammatory systemic rheumatic diseases: It is all about the patient!

The aim of this review is to focus attention on high quality diagnostics of systemic inflammatory rheumatic diseases. Though many steps in the diagnostic process from the first visit in a doctor’s office till a final diagnosis have been established a lot of things still must be done to improve quality assurance and secure fast and safe transmission of data from one step to the next. Some procedures inherent in early high quality diagnostics need to be worked out. A number of elements can be improved, some stumble stones can be removed, and a tighter collaboration between actors at different levels in the line of action in clinical and laboratory medicine can be organized. Several proposals have been made by international working groups such as the IUIS International Autoantibody Standardization Committee, and the EASI steering group in collaboration with their national EASI teams. Practical exercises carried out for more than three decades by the European Consensus Finding Study Group have proven to very useful. The review points at several principles worked out by these international expert groups can be useful in actual daily practice also in rheumatology. The hope is that the presentation will give rise to a continued discussion on how to link different parts of the diagnostic process together and strengthen collaboration between all teams involved in the diagnostic chain. The ultimate measure of success will be better clinical outcomes for patients and increased satisfaction in their families.

High titers of autoantibodies in patients with sickle-cell disease

OBJECTIVE

Frequency and titers of autoantibodies in patients with sickle-cell disease (SCD) have been reported as relatively high. In a prospective study of 88 patients, we examined this "hyper-autoreactivity" and its clinical consequences.

METHODS

For 1 year, patients with SCD were screened for the presence in their serum of antinuclear, anti-double-stranded DNA, antiextractible nuclear antigens, anticardiolipin antibodies, and rheumatoid factors. A population of 85 sex-matched individuals of similar ethnic origin served as controls.

RESULTS

Whereas prevalence of autoantibodies did not differ between the 2 groups, the type and rate of antinuclear antibodies were different. Autoantibodies from the SCD patients showed various immunofluorescence patterns, whereas only speckled patterns at low titers were present in controls. No antibody specificity was found in either group. SCD patients and controls displayed similar rates of anticardiolipin antibodies, but the SCD patients tended to be more frequently positive for rheumatoid factors. Six-year followup of the SCD patients did not provide any clinical evidence for onset of an autoimmune disease, except for 1 patient who developed rheumatoid arthritis, with increasing antinuclear antibodies followed by emergence of specific markers 5 years later.

CONCLUSION

Patients with SCD displayed high titers of autoantibodies. This observation may be due only to immune activation and/or dysfunction in SCD, as neither pathogenic specificity of autoantibodies nor autoimmune clinical signs appeared in the majority of cases in our study.

The impact of the EUSCLE core set questionnaire for the assessment of cutaneous lupus erythematosus

Epidemiological data and standard European guidelines for the diagnosis and treatment of cutaneous lupus erythematosus (CLE) are lacking in the current literature. In order to provide a standardized tool for an extensive consistent data collection, a study group of the European Society of Cutaneous Lupus Erythematosus (EUSCLE) recently developed a Core Set Questionnaire for the assessment of patients with different subtypes of CLE. The EUSCLE Core Set Questionnaire includes six sections on patient data, diagnosis, skin involvement, activity and damage of disease, laboratory analysis, and treatment. An instrument like the EUSCLE Core Set Questionnaire is essential to gain a broad and comparable data collection of patients with CLE from different European centres and to achieve consensus concerning clinical standards for the disease. The data will also be important for further characterization of the different CLE subtypes and the evaluation of therapeutic strategies; moreover, the EUSCLE Core Set Questionnaire might also be useful for the comparison of data in clinical trials. In this review, the impact of the EUSCLE Core Set Questionnaire is discussed in detail with regard to clinical and serological features as well as therapeutic modalities in CLE. Lupus (2010) 19, 1144—1152.

Automated evaluation of autoantibodies on human epithelial-2 cells as an approach to standardize cell-based immunofluorescence tests

Introduction

Analysis of autoantibodies (AAB) by indirect immunofluorescence (IIF) is a basic tool for the serological diagnosis of systemic rheumatic disorders. Automation of autoantibody IIF reading including pattern recognition may improve intra- and inter-laboratory variability and meet the demand for cost-effective assessment of large numbers of samples. Comparing automated and visual interpretation, the usefulness for routine laboratory diagnostics was investigated.

Methods

Autoantibody detection by IIF on human epithelial-2 (HEp-2) cells was conducted in a total of 1222 consecutive sera of patients with suspected systemic rheumatic diseases from a university routine laboratory (n = 924) and a private referral laboratory (n = 298). IIF results from routine diagnostics were compared with a novel automated interpretation system.

Results

Both diagnostic procedures showed a very good agreement in detecting AAB (kappa = 0.828) and differentiating respective immunofluorescence patterns. Only 98 (8.0%) of 1222 sera demonstrated discrepant results in the differentiation of positive from negative samples. The contingency coefficients of chi-square statistics were 0.646 for the university laboratory cohort with an agreement of 93.0% and 0.695 for the private laboratory cohort with an agreement of 90.6%, P < 0.0001, respectively. Comparing immunofluorescence patterns, 111 (15.3%) sera yielded differing results.

Conclusions

Automated assessment of AAB by IIF on HEp-2 cells using an automated interpretation system is a reliable and robust method for positive/negative differentiation. Employing novel mathematical algorithms, automated interpretation provides reproducible detection of specific immunofluorescence patterns on HEp-2 cells. Automated interpretation can reduce drawbacks of IIF for AAB detection in routine diagnostics providing more reliable data for clinicians.

Markers of autoimmune liver diseases in postmenopausal women with osteoporosis

INTRODUCTION

Osteoporosis is a common complication of chronic liver diseases. However, there is limited information about autoimmune liver diseases as a factor of secondary osteoporosis. Therefore, we aimed to investigate the autoantibodies of autoimmune liver diseases in patients with osteoporosis.

METHODS

One hundred fifty female patients with postmenopausal osteoporosis were included. Bone mineral density was measured by dual energy X-ray absorptiometry. We analysized autoantibodies including antinuclear antibodies, liver membrane antibodies, anti-liver/kidney microsomal autoantibodies1, liver-specific protein, antismooth muscle antibodies, and anti-mitochondrial antibodies by indirect immunofluorescence. Serum was assayed for the levels of aminotransferases.

RESULTS

The mean age of the patients was 63,13 ± 8,6 years. The mean values of L1-L4 T-scores and femur total T-scores were -3,08 ± 0,58 and -1,53 ± 0,81, respectively. Among the 150 patients with osteoporosis, 14 (9.3%) were antinuclear antibodies, four (2.7%) were liver membrane antibodies, three (2.0%) were anti-liver/kidney microsomal autoantibodies1, and two (1.3%) were liver-specific protein positive. None of the patients had anti-mitochondrial antibodies or smooth muscle antibodies positivity. The mean values of levels of aminotransferases were within normal range.

CONCLUSIONS

The presence of liver membrane antibodies, liver-specific protein, and anti-liver/kidney microsomal autoantibodies1 has permitted us to see that there may be some suspicious clues of autoimmune liver diseases in patients with osteoporosis as a secondary risk factor. On the other hand, there is a need for comprehensive studies with a larger sample size and studies designed to compare the results with a normal population to understand the clinical importance of our findings.

Progress and regression within primary Sjögren's syndrome

The purpose of this review is to give a modern view and an update of important areas in primary Sjögren's syndrome (SS), which may be the most common of the autoimmune systemic rheumatic diseases. Interest in aspects of primary SS including clinical manifestations, pathogenesis, aetiology, treatment, prognosis, etc has increased during the past three decades, the volume of scientific papers and the number of theses being the indicators. However, only a fraction of the money that is used for research into rheumatoid arthritis (RA) is used for SS, and the statement that SS is under-diagnosed, under-treated and under-researched will still be valid for several years to come. The topics that are focused on in this review are: (a) clinical areas with subsections on signs and symptoms, terminology, predictors for development of non-Hodgkin malignant lymphoma (NHML) and prognosis, (b) treatment, (c) the Danger model (aetiopathogenesis) and (d) pathology, including immunoglobulin G4 (IgG4)-positive cells.

Challenges of automated screening and differentiation of non-organ specific autoantibodies on HEp-2 cells

Analysis of autoantibodies (AAB) by indirect immunofluorescence (IIF) remains the hallmark of diagnosing autoimmune diseases despite the introduction of multiplex techniques. Non-organ specific AAB are screened in routine diagnostics by IIF on HEp-2 cells. However, IIF results vary due to objective (e.g., cell fixation) and subjective factors (e.g., expert knowledge). Therefore, inter- and intralaboratory variance is relatively high. Standardisation of AAB testing by IIF remains a critical issue in and between routine laboratories and may be improved by automated interpretation systems. An overview of existing interpretation techniques will be given taking into account own data of the first fully automated reading system AKLIDES. The novel system provides fully automated reading of IIF images and software algorithms for the mathematical description of IIF AAB patterns. It can be used for screening and preclassification of non-organ specific AAB in routine diagnostics regarding systemic autoimmune and autoimmune liver diseases. Furthermore, this system paves the way for economic data processing of cell-based IIF assays and can contribute to the reduction of interlaboratory variance of AAB testing. More sophisticated pattern recognition algorithms and novel calibration systems will improve standardised quantifications of IIF image interpretation.

Screening Autoantibody Profiles in Systemic Rheumatic Disease with a Diagnostic Protein Microarray That Uses a Filtration-Assisted Nanodot Array Luminometric Immunoassay (NALIA)

Background: We developed a cost-efficient modular system for multiplex analysis of the multiple autoantibodies that characterize systemic rheumatoid diseases.

Methods: The nanodot array luminometric immunoassay (NALIA) system consists of conventional 96-well membrane-bottomed plates in which antigens or antibodies are adsorbed onto the underside of the membrane. Current arrays use a 5 × 5 format (25 dots/well), which allows 10 analytes to be measured in duplicate: double-stranded DNA (dsDNA), centromere protein B (CENP-B), PCNA, Sm, Sm ribonucleoprotein (Sm-RNP), U1-snRNP, Scl70, SSA/Ro, SSB/La, Jo-1, and controls. The test fluid, control sera, and subsequent reagents are drawn through the membrane. The captured analytes are quantified by monitoring chemiluminescence with a charge-coupled device (CCD) and analyzed with commercial array software.

Results: The assay can detect &lt;20 × 103 IU/L of anti-dsDNA. The interwell CV was 10%–14%. There was an 83% concordance (κ = 0.56) between the NALIA results obtained for anti-dsDNA assayed by β-testing in a routine immunology diagnostic laboratory and the results obtained with a conventional ELISA reagent set. The concordance values for Ro, La, Sm, and RNP were 98% (κ, 0.92), 93% (κ, 0.41), 97% (κ, 0.62), and 97% (κ, 0.73), respectively.

Conclusion: The NALIA approach promises to provide a highly economical platform for a wide range of applications that require assays of multiple analytes. The degree of concordance of our results with a conventional reagent set was no less than that occurring between different commercial products. A sample of serum from a finger stick provides a volume sufficient to perform the array assay.

Are Anti-Nuclear Antibodies Common in Affective Disorders? A Review of the Past 35 Years

There has been debate in the literature about whether or not positive anti-nuclear antibody (ANA) titers are associated with affective disorders. Using specific search criteria, the author conducted a search of PubMed over the past 35 years. Four studies showed a positive correlation, whereas eight did not. Some of the positive studies have confounding factors. Given that the positive studies have confounding factors and that there are more negative studies than positive ones, it is logical to assume that there is no association between ANA titer and affective disorders until a properly controlled study is conducted.

Diagnostische Strategien bei rheumatischen Autoimmunerkrankungen

In order to help the clinical rheumatologist set an early and precise diagnosis and plan a rational follow-up, a close collaboration between all parties involved in the diagnostic work-up must be established. Autoimmune serology plays a key role in achieving this goal by choosing test methods that are ideal from a clinical standpoint and by presenting results obtained in such a fashion that even less experienced clinicians can correctly use the information. Simple algorithms for test ordering and for the interpretation of laboratory findings are of great benefit in daily practice, but such tools must be mutually agreed upon by the laboratory and clinical scientists. A precise diagnosis and estimation of prognosis is instrumental for optimal decision making in the clinic, but this is too complicated to be left to chance due to the inappropriate use of information. Late or wrong decisions during follow-up lead to unnecessary suffering and far higher lifetime costs for chronic diseases such as those found in rheumatology.

Quantitation of autoantibodies in systemic autoimmune diseases: clinically useful?

Serial assessment of levels of autoantibodies has been proposed as being clinically useful in certain systemic autoimmune diseases. In particular, attention has been given to anti-dsDNA antibodies in systemic lupus erythematosus (SLE) and ANCA in the ANCA-associated vasculitides (AAV). Much controversy exists, however, concerning the value of serial testing in these diseases. We here review the various tests available for quantitation of anti-dsDNA and ANCA, and their capacity to detect changes in autoantibody levels that are associated with changes in clinical disease activity of the respective diseases. It is concluded that changes in anti-dsDNA as measured by the Farr assay and changes in ANCA as assessed by ELISA have predictive value for the occurrence of disease relapses, although this relationship is far from absolute. Consequently, treatment based on changes in levels of the respective autoantibodies only seems at present not justified, in view of the toxicity of currently available immunosuppressive regimens.

Labordiagnostik der systemischen Autoimmunerkrankungen

This is the first part of a series of articles on the laboratory diagnostics of rheumatic diseases and will consider the systemic autoimmune diseases lupus erythematosus, Sjögren's syndrome, systemic sclerosis, dermato/polymyositis and mixed connective tissue disease (MCTD, SHARP syndrome). The basis for diagnostics is the presence of antinuclear antibodies (ANA). Initially, these antibodies are detected using a screening test. This must be followed by the identification of the patient's individual autoantibody specificities, which then yields important diagnostic clues. Disease activity may be monitored serologically by following the titers of selected autoantibodies and, in certain patients, by examining complement consumption.

T cell cytokine imbalance towards production of IFN-gamma and IL-10 in NZB/W F1 lupus-prone mice is associated with autoantibody levels and nephritis

OBJECTIVE

The role of T cell-derived cytokine production in lupus is poorly understood. We analysed the cytokine production of CD4(+) T cells in the NZB/W F1 mouse strain, the mouse model probably most closely resembling human systemic lupus erythematosus (SLE), and assessed whether a possible shift in the cytokines expressed is associated with age or disease activity.

METHODS

We used intracellular cytokine staining and flow cytometry to determine the cytokine expression of splenic CD4(+) T cells for interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), interleukin-4 (IL-4) and IL-10. NZB/W F1 mice at different ages spanning 5 to 36 weeks were analysed, healthy Balb/cxNZW F1 (CWF1) mice were used as controls. Serum anti-double-stranded DNA (anti-dsDNA) antibody levels were determined by enzyme-linked immunosorbent assay (ELISA), and proteinuria and plasma creatinine were estimated using commercial test kits.

RESULTS

The cytokine profile of CD4(+) T cells was shifted towards T-helper 1 (Th1) cells and the frequencies of Th cells expressing IFN-gamma(+) correlated with age, anti-dsDNA-immunoglobulin G (IgG) titre and proteinuria. An increased percentage of IL-10 producers correlated positively with anti-dsDNA-IgG and proteinuria, and a small gain in IL-4 producers correlated with plasma creatinine. Neither the percentage of IL-10 producers nor IL-4 producers showed a significant correlation with age. There was no significant change observed in the frequency of TNF-alpha T cells. The IFN-gamma/IL-4 ratio demonstrated an increasing shift towards a Th1-type response during disease development that was not present in healthy mouse strains.

CONCLUSION

The association between the frequencies of T cells expressing IFN-gamma and IL-10 and clinical findings suggests a key role for these cells in the pathogenesis of lupus.