1. Assess the serum level of TPI in patients with RA compared to healthy controls.
2. Correlate serum level of TPI and disease activity.
3. Correlation of serum TPI level with US7 damage index

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by persistent synovial inflammation, synovial hyperplasia, and progressive destruction of bone and cartilage. These pathological processes can lead to joint deformities and loss of function, significantly affecting patients' quality of life. In addition to joint damage, RA often manifests with extraarticular complications involving the cardiovascular, pulmonary, and other organ systems. These systemic effects impose a substantial burden on patients' physical and mental well-being, as well as their socioeconomic status .The disease often affects subjects between the ages of 40 and 70; however, it can also occur at a younger age. Globally, the prevalence rate of RA is approximately 1%, with females experiencing a higher incidence . Triosephosphate isomerase (TPI) is a metabolic enzyme that regulates the flow of glycolysis and energy generation by converting dihydroxyacetone phosphate (DHAP) into D- glyceraldehyde 3-phosphate (G3P). TPI is one of the glycolytic enzymes implicated in the pathogenesis of RA.

Additionally, it has been shown to possess functions beyond glycolysis, including potential roles in the nucleus related to cancer pathogenesis and chemotherapy resistance . Some studies showed a significant correlation between elevated TPI levels and RA, with TPI serving as an independent predictor of the disease. With some findings, which include a high sensitivity of 98.5% and specificity of 100%, suggest that TPI could be a valuable biomarker for the early diagnosis and management of RA

Inclusion Criteria:

- Adult patients with RA who fulfill 2010 ACR/EULAR classification criteria

Exclusion Criteria:

1. Individuals with uncontrolled chronic diseases such as hypertension , diabetes, heart disease, liver or kidney disease, other autoimmune disorders and tumors.
2. Pregnant women.
3. Rheumatologic diseases other than RA

Adult RA patients and age- and sex-matched healthy controls will be included