A serological study has been done in Al-Nassiriyha, southern Iraq, from December 2006 to
August 2007 designed to determine the frequency of anti-cyclic citrullinated peptide antibody
(anti-CCP) in a group of patients with rheumatoid arthritis for specific period of time compared
with other rheumatic diseases and healthy controls. Also to show the diagnostic value of
anti-CCP antibody in relation to other markers [rheumatoid factor (RF), antinuclear factor (ANF),
C-reactive protein (CRP) and cytokines such as interleukin–6 (IL-6), tumor necrosis factor–α
(TNF-α)] to discriminate between those patients with and without RA.
Blood samples were taken from 121 patients with rheumatoid arthritis, 88 patients of other
rheumatic diseases from AL-Hussein Teaching Hospital in AL-Nassiriyah and 120 healthy
controls from medical personnel and school students who were healthy. All the information was
taken from the patients and controls.
An Enzyme-linked immunosorbent assay was used for estimation of anti-CCP, IL-6, TNF-α and
slide agglutination test for the estimation of RF, CRP and ANF. The seropositivity to anti-CCP in
RA patients group was 61.2% among them 23% with low levels of anti-CCP, 25% with
moderate levels and 51.3% with high levels (> 60 units /ml.).The high levels of anti-CCP persist
for long durations up to 10 years (54.7%). However, anti-CCP was rarely detected among non-
RA rheumatic diseases and healthy controls (2.3% and 2.5% respectively). Anti-CCP showed
the greater specificity (97.6%) and sensitivity (61.2%) compared to the other marker used in this
study. The overall agreement between the tested parameters in their ability to detect RA patient
was higher for anti-CCP combined to IL-6 (91.7%) in comparison to the effect of other markers
combination. Although anti-CCP was more common in RA patient with 2-10 years duration of
illness, anti-CCP, IL-6 and TNF-α positivity as estimated by ELISA were persistently with high
titers regardless the duration of illness. The majority of RA patients with high anti-CCP levels
were among stage three of clinical RA. Smoking has a positive relation to the increased levels
of all tested parameters compared to the non-smokers.