Bone & Joint Health Checkup

Antinuclear antibody (ANA) test screens for the presence of ANA in blood. The immune system of the body is responsible for differentiating between the body’s own cells and foreign cells, like pathogens. Once the foreign cells are identified, they are then targeted and destroyed. In autoimmune disorders, the immune system of the body is unable to recognize certain cells as the body’s own cells and starts an immune response against them which results in their destruction. The recognition of ‘self’ and ‘non-self’ cells is mediated by certain proteins present on the surface of cells or inside them. When the immune system identifies a cell as foreign or ‘non-self’, it produces antibodies against these cells to destroy them. Antibodies produced in an autoimmune disease are called autoantibodies.

Antinuclear antibodies (ANA) are autoantibodies that are produced against protein markers present in the nucleus of certain cells of the body. They are produced in a number of autoimmune diseases but are most commonly produced in Systemic Lupus Erythematosus (SLE).

The Antinuclear Antibody Test can be performed either by Immunoassay method (ELISA) or Indirect Fluorescent Antibody (IFA) method to detect ANA in blood. Both these tests may be used by some laboratories together: the Immunoassay method (ELISA) screens for the presence of antinuclear antibodies, and IFA method subsequently confirms the positive or equivocal Immunoassay results.

ANA by Immunoassay method (ELISA) utilizes a mixture of known anti-nuclear antigens and is fairly simple to perform, can be automated and provides fairly objective results.

Ph, Serum measures the levels of inorganic phosphates in blood. It is critical in the production and storage of energy as it forms a part of the energy currency of cells (Adenosine tri, di, and monophosphates). It is also a structural component of DNA. It is essential in the functioning of nerves and muscles, and in the growth and maintenance of healthy bones. In blood, phosphates act as buffers to maintain the pH and electrolyte balance of the body.

The main source of phosphorus comes from diet. Once consumed, it is quickly absorbed by the digestive system. In the body, most of the phosphates are bound to calcium in the bones and teeth. Some of it is found in muscles and nerves, and a small amount is present in cells, where it forms a structural component of DNA. Very small amounts of phosphates are normally found in circulation, and these levels are measured with blood phosphorus levels.

Phosphate levels in the blood are maintained within its very narrow normal concentration range by excretion of excess phosphorus through kidneys. Phosphate levels are also dependent on the levels of calcium, Vitamin D and parathyroid hormone in blood.

Rheumatoid factor (RF) attacks healthy body tissues as it mistakes them for foreign body tissues. It is not found in healthy persons. The presence of RF means that the body has an autoimmune disease such as Rheumatoid arthritis. Symptoms of Rheumatoid arthritis include stiffness of joints especially in morning, pain in joints, underlying skin nodules, loss of bone and swelling of joints.