Pattern on the antinuclear antibody–HEp‐2 test is a critical parameter for discriminating antinuclear antibody–positive healthy individuals and patients with autoimmune rheumatic diseases

Abstract

Objective. To identify features of antinuclear antibody (ANA)-HEp-2 test results that discriminate ANA-positive healthy individuals and patients with autoimmune rheumatic diseases (ARDs).Methods. We sequentially retrieved data on 918 healthy individuals and 153 patients with ARDs after clinical assessment. ANA-positive healthy individuals for whom data were available were reevaluated after 3.6-5.0 years. An ANA-HEp-2 test result was considered positive when a clear ANA pattern was observed at 1:80 dilution in 2 distinct commercial HEp-2 slides by 2 blinded independent observers.Results. ANAs were present in 118 healthy individuals (12.9%) and 138 patients with ARDs (90.2%). The ANA titer was higher in patients with ARDs than in healthy individuals (P < 0.001). The ANA pattern profile was distinct in the 2 groups. Nuclear homogeneous, nuclear coarse speckled, and nuclear centromeric patterns appeared exclusively in patients with ARDs. The nuclear dense fine speckled pattern occurred only in healthy individuals. The most frequent ANA pattern in both groups was the nuclear fine speckled pattern, which occurred at lower titer in healthy individuals than in patients with ARDs (P < 0.001). Antiextractable nuclear antigen was present in 1 healthy individual (anti-SSA/Ro) and in 52 patients with ARDs (37.7%). None of the 40 reevaluated healthy individuals developed ARDs, and 29 (72.5%) remained ANA positive. All healthy individuals who became ANA negative had an ANA titer of 1:80 at baseline.Conclusion. Our findings suggest that the titer, and especially the pattern, on the ANA-HEp-2 test strongly enhances our ability to discriminate ANApositive healthy individuals and patients with ARDs.

Cigarette smoking in patients with systemic sclerosis reduces overall survival: Comment on the article by Hudson et al

“…There was no association of smoking history (ever smoked, never smoked, or pack-year history) with any clinical variables (vascular, gastrointestinal, or respiratory) studied in our cohort, which reemphasizes the usefulness of appropriate statistical analysis to elucidate the association described by Hudson et al (1). However, our cumulative proportional survival analysis revealed that survival was decreased in past or present smokers (i.e., those designated as ever having smoked) compared with those who had never smoked ( Figure 1A).…”

“…We commend Hudson and colleagues on their study demonstrating the adverse effects of smoking in scleroderma (1). They used a well-designed Comprehensive Smoking Index (2) for evaluating all vascular, gastrointestinal, and respiratory outcomes, applying simple exposure variables (e.g., ever smoking, never smoking, or pack-years of smoking) to a few clinical outcomes.…”

“…We read with interest the recent article by Mariz et al (1), which presents data on the frequency of the dense fine speckled antinuclear antibody (ANA) pattern, as measured by indirect immunofluorescence assay using HEp-2 cells as substrate. This pattern was observed in 39 (33.0%) of the 118 healthy individuals studied who had an ANA titer of Ն1:80, but in none of the 138 ANA-positive patients with autoimmune rheumatic disease (ARD).…”

Variability in the recognition of distinctive immunofluorescence patterns in different brands of HEp-2 cell slides

“…In fact, national and international studies estimate a frequency of approximately 13% positive results and titer of 1/80 in the general population (11,17) . This scenario becomes even more problematic in view of the widespread use of this test.…”

“…In fact, in recent years the relevance of IIF on ANA-HEp-2 interpretation has been consistently emphasized (11) . The observed pattern may provide preliminary information on the nature of the autoantibody in a given sample and even indicate which additional and specific tests should be conducted.…”