Antibody Pattern Identifies Rheumatic Disease Patients
Titer and pattern of the ANA-HEp-2 test differentiates between patients with ARDs and controls
TUESDAY, Jan. 11 (HealthDay News) -- Antinuclear Antibody-HEp-2 (ANA-HEp-2) pattern and titer can be used to differentiate between ANA-positive healthy individuals and patients with autoimmune rheumatic diseases (ARDs), according to results from a study published in the January issue of Arthritis & Rheumatism.
Henrique A. Mariz, M.D., from the Universidade Federal de Sao Paulo in Brazil, and colleagues examined clinical data from 918 healthy individuals and 153 patients suffering from ARDs. The ANA-HEp-2 test was considered positive when a well-defined ANA pattern was identified in two HEp-2 slides by two independent investigators.
Researchers found that the presence of ANAs was detected in 12.9 percent of healthy individuals (false-positives) and in 90.2 percent of patients with ARDs. The ANA titer was significantly higher in patients with ARDs than in healthy controls. Healthy patients had a nuclear dense fine speckled (NDFS) or nuclear fine speckled (NFS) pattern. Patients with ARDs did not have the NDFS pattern, but presented with NFS at higher titer than healthy individuals, and had a distinct profile with nuclear coarse speckled, nuclear homogenous, nuclear centromeric, and cytoplasmic dense fine speckled patterns. At the end of the four-year follow-up period, 72.5 percent of the ANA-positive healthy individuals still tested positive, but did not have symptoms of ARDs.
"The ANAHEp-2 assay offered distinctive titer and pattern profiles for ANA-positive healthy individuals and for patients with ARDs. The ANA pattern on the test seemed to be more consistent than the ANA titer for discriminating ANA-positive healthy individuals and patients with ARDs," the authors write.