Current laboratory and clinical practices in reporting and interpreting anti-nuclear antibody indirect immunofluorescence (ANA IIF) patterns: results of an international survey

Abstract

Background The International Consensus on Antinuclear Antibody (ANA) Patterns (ICAP) has recently proposed nomenclature in order to harmonize ANA indirect immunofluorescence (IIF) pattern reporting. ICAP distinguishes competent-level from expert-level patterns. A survey was organized to evaluate reporting, familiarity, and considered clinical value of ANA IIF patterns. Methods Two surveys were distributed by European Autoimmunity Standardization Initiative (EASI) working groups, the International Consensus on ANA Patterns (ICAP) and UK NEQAS to laboratory professionals and clinicians. Results 438 laboratory professionals and 248 clinicians from 67 countries responded. Except for dense fine speckled (DFS), the nuclear competent patterns were reported by > 85% of the laboratories. Except for rods and rings, the cytoplasmic competent patterns were reported by > 72% of laboratories. Cytoplasmic IIF staining was considered ANA positive by 55% of clinicians and 62% of laboratory professionals, with geographical and expertise-related differences. Quantification of fluorescence intensity was considered clinically relevant for nuclear patterns, but less so for cytoplasmic and mitotic patterns. Combining IIF with specific extractable nuclear antigens (ENA)/dsDNA antibody testing was considered most informative. Of the nuclear competent patterns, the centromere and homogeneous pattern obtained the highest scores for clinical relevance and the DFS pattern the lowest. Of the cytoplasmic patterns, the reticular/mitochondria-like pattern obtained the highest scores for clinical relevance and the polar/Golgi-like and rods and rings patterns the lowest. Conclusion This survey confirms that the major nuclear and cytoplasmic ANA IIF patterns are considered clinically important. There is no unanimity on classifying DFS, rods and rings and polar/Golgi-like as a competent pattern and on reporting cytoplasmic patterns as ANA IIF positive.

ANA-specific antibodies, ANA patterns, anti-ds-DNA results, and clinical diagnosis: a laboratory and clinical audit

“…In the recent past, autoantibody testing for systemic rheumatic diseases has been revolutionized [9]. The integrated approach of ANA patterns and extended panels of ANA-speci c antibodies have both reduced the time-lapse in diagnosing the disease and misdiagnosis [10]. Moreover, the Interpretation and reporting of ANA have been standardized to reduce subjectivity [11].…”

The Prevalence and Clinical Relevance of the DFS Immunofluorescence Staining Pattern in a Large ANA-Positive Cohort

“…Initially, reported in patients with interstitial cystitis, later studies observed this pattern in a wide spectrum of clinical conditions, such as chronic inflammation, asthma, atopic dermatitis, autoimmune thyroiditis, as well as in apparently healthy individuals ( 25 , 26 ). Despite sharing morphological similarity with the nuclear homogeneous pattern (AC-01), the DFS pattern has a completely different clinical significance that needs to be clarified ( 27 ). To date, the DFS pattern has mainly been linked to anti-DFS70 antibodies in various studies.…”

Anti-ENA Antibodies, ANA Patterns, Anti-ds DNA results, and Clinical Diagnosis: A Laboratory and Clinical Audit.

“…In the recent past, autoantibody testing for systemic rheumatic diseases has been revolutionized [9]. The integrated approach of ANA patterns and extended panels of anti-ENA antibodies have both reduced the time-lapse in diagnosing the disease and misdiagnosis [10]. Moreover, the Interpretation and reporting of ANA have been standardized to reduce subjectivity [11].…”

“…A very important factor is clinicians' understanding and acceptance of the revised reporting format of these autoantibodies. As they are familiar and more comfortable with the ANA test results and interpretation, introducing the concept of anti-cellular antibodies (ACA) with the importance of anti-cytoplasmic antibodies and anti-mitotic antibodies will require their continuous education [10,13].…”