There is no single test for Arthritis. Investigations and imaging studies would make a physician to understand the pathophysiology behind and very helpful in remedy selection. It also favours an added study on prognosis of the patient.

Blood screening

1.Immunological studies
    Abnormal blood antibodies can be found in patients with rheumatoid arthritis. A blood antibody called “Rheumatoid factor” can be found in many patients. Citrulline antibody (also referred to as anti-citrulline antibody, anti-cyclic citrullinated peptide antibody, and anti-CCP) is present in most patients with rheumatoid arthritis. It is useful in the diagnosis of rheumatoid arthritis when evaluating patients with unexplained joint inflammation. A test for citrulline antibodies is most helpful in looking for the cause of previously undiagnosed inflammatory arthritis when the traditional blood test for rheumatoid arthritis, rheumatoid factor, is not present. Citrulline antibodies have been felt to represent the earlier stages of rheumatoid arthritis in this setting. Another antibody called “the antinuclear antibody” (ANA) is also frequently found in patients with rheumatoid arthritis.Inherited HLA-B27 antigen may give an valuable diagnosis of Ankylosing spondylosis and Psoriatic arthritis

    Another blood test that is used to measure the degree of inflammation present in the body is the C-reactive protein. The levels (titres) of ASO (Anti streptolysin O)reach the highest at the beginning of rheumatic fever and also gives detail of recent streptococcal infection

2.ESR
    TESR is high in disease flares, and slower during remissions. Therefore, abnormalities in these blood tests alone are not sufficient for a firm diagnosis of rheumatoid arthritis.

    An elevated “Uric Acid level” may rule Gout

X-Rays
    TX-rays of joints can indicate whether you have any of the characteristic signs of osteoarthritis ,reactive arthritis, including soft tissue swelling, calcium deposits where tendons attach to bones and cartilage damage. X-rays can also rule out other types of arthritis.

Culture
    Cultures to see if you have any of the infections often associated with reactive arthritis. These tests involve placing samples of body fluids onto a substance that enhances the growth of bacteria. However, some bacteria are difficult to grow in the laboratory, so other microbiologic tests may be performed. Alternatives include blood tests that detect antibodies against bacteria (serologic tests) and polymerase chain reaction (PCR) — a test that can identify portions of genetic material (DNA).