Some Aspect of Accuracy of Acpa Assay in Patients with Psoriatic Arthritis

Abstract

Aims:To compare the values and acuracy of the test in anticyclic citrullinated

peptides (Anti-CCP /ACPA) antibodies, Rheumatoid factor (RF), C-Reactive Protein (CRP) and disease activity index (PASI) in early diagnosis of untreated Psoriatic arthritis(PsA).

Methods:Using the ELISA method of DIA-STAT^TM  Anti CCP (Axis–Shield Diagnostics), sera of 70 participants were examined (35 untreated patients with PsA and 35 persons from the healthy control group). RF and CRP were determined with the agglutination test (Lateks test) in the same participants. In the same time we determined the sensitivity, specificity, predictive value for positive and negative test and accuracy.

Results:From 35 pts with PsA, 1 patient showed presence of Anti-CCP antibodies (sensitivity test 2.86%), while RF was present in 0 pts (sensitivity test 0%). In the healthy control group positive values for RF, CRP and Erythroid Sedimentation Rate (ESR) were detected in 1 participant.

Conclussion:ACPA antibodies have low sensitivity, but high specificity in PsA.

Key words: Anti cyclic citrullinated peptide (Anti-CCP) Psoriatic arthritis (PsA), Rheumatoid factor (RF)