Description
Enzymatic homocysteine assay is intended for the in vitro quantitative determination of total L-homocysteine in serum or plasma. Homocysteine (Hcy) is a thiol-containing amino acid produced by the intracellular demethylation of methionine. Total homocysteine (tHcy) represents the sum of all forms of Hcy including forms of oxidized, protein bound and free. Elevated level of tHcy has emerged as an important risk factor in the assessment of cardiovascular disease. Excess Hcy in the blood stream may cause injures to arterial vessels due to its irritant nature, and result in inflammation and plaque formation, which may eventually cause blockage of blood flow to the heart. Elevated tHcy levels are resulted from four major causes including: genetic deficiencies in enzymes involved in Hcy metabolisms such as cystathionine beta-synthase (CBS), methionine synthase (MS), and methylenetetrahydrofolate reductase (MTHFR); nutritional deficiency in B vitamins such as B6, B12 and folate; renal failure for effective amino acid clearance, and d) drug interactions such as nitric oxide, methotrexate and phenytoin that interfere with Hcy metabolisms. Elevated levels of tHcy are also linked with Alzheimer’s disease and Osteoporosis. Guidelines for tHcy determination in clinical laboratories have recently been established. The assay can assist in diagnosis and treatment of patients suspected of having hyperhomocysteinemia and homocystinuria. The assay is not intended for correlating B12 or folate with homocysteine levels.