Anti-perinuclear Factor as Diagnostic Marker in Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is a systemic autoimmune disease. It is associated with several auto antibodies which can serve as diagnostic and prognostic markers.

In this study, Anti perinuclear Factor (APF) was evaluated as a biomarker in comparison with Rheumatoid Factor (RF) in Rheumatoid Arthritis.

Fifty two sera of patients with RA (mean age 48±15.8), 23 sera of Patient control group (mean age 32.5 ± 16.9) and 30 sera of Healthy control group (mean age 32.1± 16.9) were analysed. The method is based on the binding of APF to perinuclear keratohyalin granules of buccal mucosal cell and its detection using a fluorescently labeled anti human total antiserum.

APF were found in 71.2 %(37/52) of patients with RA. The sensitivity and specificity for APF from 1/5 serum dilution was 71.2% and 94.3% respectively. RF test had higher sensitivity (88.5%) compare to the APF test (71.2%), but its specificity was (86.8%) less than APF (94.3%). There was no significant relationship between the onset of APF and severity of disease but there was significant relationship between the APF titer and severity of disease (p<0.05).

It is concluded that APF test is a valuable serological tool for the diagnosis of the disease and a useful serological marker to differentiate from the other inflammatory rheumatoid diseases.