The Relationship Between Serum Chemokine Ligand 21 (CCL-21) Level and Disease Activity

Laboratory tests (examination) to be performed include complete blood count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), liver function tests and kidney function tests; rheumatoid factor (RF), anti-cyclic citrullinated peptide antibody (anti-CCP antibody) and C-C Motif Chemokine Ligand 21 (CCL21).

Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) This questionnaire is used to assess the health status of osteoarthritis patients introduced in 1988 (13). It is consisted of 33 items which evaluates the health and function of the patient from various aspects including: clinical symptoms (5 questions), severity of joint stiffness (2 questions), degree of pain (9 questions), and activity of daily living (17 questions).The test questions are scored on a scale of 0-4, which correspond to: None(0),Mild (1),Moderate (2),Severe(3),and Extreme (4).The scores for each subscale are summed up, with a possible score range of 0-20 for Pain, 0-8 for Stiffness, and 0-68 for Physical Function. Usually a sum of the scores for all three subscales gives a total WOMAC score, however there are other methods that have been used to combine scores.Higher scores on the WOMAC indicate worse pain, stiffness, and functional limitations.

The Disease Activity Score (DAS) was created as a numerical tool for quantifying and assessing disease activity in rheumatoid arthritis (RA).The DAS28 (Disease Activity Score using 28 joint counts) was developed from the original DAS (Disease Activity Score).The DAS28 evaluates the disease activity by assessing the number of tender and swollen joints in a patient. Specifically, it considers 28 joints. The DAS28 also takes into account a blood marker of inflammation, typically the erythrocyte sedimentation rate (ESR) or the C-reactive protein (CRP) level.A patient with a DAS28 score of less than 2.6 is in remission; a score greater than or equal to 2.6 and less than 3.1 indicates low activity; a score greater than or equal to 3.1 and \<5.1 indicates moderate activity and a score 5.1 or more indicates high activity

Patient global assessment (PGA) of disease activity will be reported by patients. PGA was developed in the late 1970s and was initially designed for the measurement of self-assessed pain in RA \[8\], although it has since been used to evaluate RA more globally. It is interesting to note that the way PGA is used in clinical practice covers, in fact, two very different concepts, one related to global health and the other to overall disease activity. They are both usually used under the heading of PGA without further specification for which is being assessed.

Physician global assessment (PhGA)of disease activity will be reported by the physician.The Physician Global Assessment (PhGA) of treatment response measures the overall response to treatment as assessed by the physician. The PhGA is a well accepted and commonly used scale for evaluating treatment response in clinical trials both in adults and children. PhGA is a simple instrument and the result is easily understood. However, assigning a score for PhGA requires a very detailed evaluation. To perform this assessment a physician/health care provider would use extensive data from every aspect of ICF.

Functional impairment will be assessed with the Health Assessment Questionnaire (HAQ). It is a self-assessment tool used to measure functional ability in eight different areas: rising, dressing and grooming, hygiene, eating, walking, reach, grip, and activities of independent living. Each item or question is rated on a scale of 0 to 3, with 0 (normal/no difficulty), 1 (some difficulty), 2 (much difficulty), and 3 (unable to do). The 8 category scores are averaged, which represent an overall score from 0 (no disability) to 3 (completely disabled). If the questionnaire is slightly changed to reflect a certain disease, this does not affect the respective scoring.Scores 0-1 indicates mild to moderate disability, 1-2 indicates moderate to severe disability, and 2-3 indicates severe to very severe disability.

Clinical Disease Activity Index (CDAI) is a composite index (without acute-phase reactant) for assessing disease activity. CDAI is based on the simple summation of the count of swollen/tender joint count of 28 joints along with patient and physician global assessment on VAS (0-10 cm) Scale for estimating disease activity. The CDAI has range from 0 to 76

The Simplified Disease Activity Index for Rheumatoid Arthritis (SDAI) is a scoring system that has been validated in both research and clinical settings. It has been shown to have the highest sensitivity and specificity for predicting a physicians' decisions to change DMARD therapy when compared to other scores.Remission is defined as an SDAI of \<3.3, low disease activity as ≤11, moderate disease activity as ≤26 and high disease activity as \>26. Response to therapy is considered moderate if SDAI decreases by ≥7 and major if decreases by ≥17

Knee osteoarthritis (gonarthrosis) will be evaluated using Kellgren-Lawrence (KL) staging on direct radiographs (anteroposterior and lateral views).Numerous variations of the Kellgren and Lawrence classification system have been used in research. Grade 0 (none): definite absence of x-ray changes of osteoarthritis. Grade 1 (doubtful): doubtful joint space narrowing and possible osteophytic lipping.Grade 2 (minimal): definite osteophytes and possible joint space narrowing. Grade 3 (moderate): moderate multiple osteophytes, definite narrowing of joint space, some sclerosis and possible deformity of bone ends Grade 4 (severe): large osteophytes, marked narrowing of joint space, severe sclerosis and definite deformity of bone ends. Osteoarthritis is deemed present at grade 2 although of minimal severity