A number of patients with inflammatory ARTHRITIS due to inadequate clinical or laboratory data do not fulfill diagnostic criteria for a clinical disease categories. These patients with initial diagnosis of undifferentiated ARTHRITIS (UA) may remit or progress to a definite well- defined condition such as rheumatoid ARTHRITIS (RA) or remain as UA with persistence of inflammatory ARTHRITIS. The main objective in the evaluation of these patients is focused on differentiating self-limiting ARTHRITIS from those who progress to chronic destructive ARTHRITIS such as RA. The study reviews the background data regarding the associated factors of progressive diseases among patients with recent-onset ARTHRITIS as well as the evaluation and decision in the management of this population. At present, the major goal should be focused on the early identification of patients, who have progressive course and initiation of appropriate therapy by using Disease Modifying Anti Rheumatic Drugs, (DMARDs) as early as possible to achieve clinical remission.

Background: Changes in patients’,Bone Mineral Density (BMD) is one of the problems in patients with rheumatoid ARTHRITIS, which can be due to the use of corticosteroid drugs to reduce patients’,symptoms or the aging process in patients. Objective: In this study, we decided to compare BMD in patients with psoriatic ARTHRITIS and rheumatoid ARTHRITIS. Methods: This study as a cross-sectional descriptive-analytical study was performed to evaluate BMD in patients with psoriatic ARTHRITIS (n=59) and rheumatoid ARTHRITIS (n=41) who were referred to Rasoul Akram Hospital in Tehran between 2016 and 2020. All patients were assessed by bone density scan (Dual-Energy X-ray Absorptiometry or DEXA scan) to determine T-score at the two spine and femur sites. Results: In rheumatoid ARTHRITIS and psoriatic ARTHRITIS groups, the Mean±, SD spine T-score was-1. 11±, 0. 18 and-1. 38±, 0. 48, respectively, which did not show a significant difference between the two groups (P=0. 556). Similarly, in the two groups with rheumatoid ARTHRITIS and psoriatic ARTHRITIS, the Mean±, SD femur T-score was-1. 36±, 0. 17 and-1. 78±, 0. 61, respectively, which did not show a significant difference between the two groups (P=0. 451). Considering the underlying parameters, including age, sex, and duration of the disease, the lack of differences in the values of spine and femur T-scores between the two groups was still evident. Conclusion: The change in BMD was equal in both rheumatoid ARTHRITIS and psoriatic ARTHRITIS that is not affected by gender, age, or duration of disease.