RÉSUMÉ
The aim of the work is to investigate the possible association of polymorphism in the transforming growth factor beta-1 [TGF beta 1] gene with the disease severity in rheumatoid arthritis. The study was conducted on 50 patients with rheumatoid arthritis [group I] diagnosed according to the American College of Rheumatology [ACR]. They were divided according to the activity of the disease [Ritchieis articular index-RAI- and ESR] into: Active group [group A]: 29 RA patients with signs of activity [having RAI >/= 16 and ESR >/= 30 mm/h]. In-active group [group B]: 21 RA patients without signs of activity [having RAI = 16 and ESR = 30 mm/h]. 15 apparently healthy volunteers [group II] as controls. All subjects in the study were subjected to the following: Full history taking: particularly for age, sex, disease duration and extra-articular manifestations, thorough clinical examination including joint examination with stress on Ritchie's articular index. Routine laboratory investigations, including CBC, ESR. Serological investigations, including rheumatoid factor, Rose-Waaler, anti- cyclic citrullinated peptide antibodies [anti CCP]. Molecular detection of TGF beta1 [T869C] polymorphism using an amplification refractory mutation system - polymerase chain reaction [ARMS-PCR]. CBC, ESR, RF, RW, anti-CCP were significantly higher in Group I than that observed in Group II. There was a significant positive correlation between the results of RF, RW, anti-CCP and the parameters of disease activity. As regards the comparison between RF, RW, Anti-CCP and the parameters of disease severity; there highly significant difference with X-ray findings, but was no significant difference between extra-articular manifestations and the results of RF and RW, while there was a significant difference with the results of anti-CCP. The diagnostic sensitivity and diagnostic specificity of RF, RW and anti-CCP at different cut off values; were 74%, 96%, 84% respectively for sensitivity and 80%, 80%, 100% respectively for specificity. With diagnostic accuracy were 0.817, 0.961 and 0.968 respectively. From the current study we can conclude that the detection of anti-CCP is very useful for the diagnosis of RA even more than RF and RW because of its prevalence, sensitivity and specificity to the disease occurrence. Anti-CCP measurement can be considered useful in clinical practice in evaluation of both disease activity and severity of RA. RF and RW reflect in some way the severity and progression of RA. The TGF peta1 gene polymorphism showed no significant association neither with the prevalence of RA nor the prediction of the disease activity or severity