Homocysteine:
Why Homocysteine Test ?
CLINICAL INFORMATION
Amino acids are components (building blocks) of protein and hence are required for protein synthesis. Homocysteine is a sulphur-containing amino acid – C4H9NO2S. Meat, fish and dairy products are rich sources of this amino acid – Homocysteine (since it is found in animal metabolism). Homocysteine is an amino acid that is an intermediate in the synthesis of cysteine (from the amino acid Methionine - this conversion requires vitamin B6, B12 and Folic acid which functions as co-enzymes). Homocysteine links methionine cycle to the folate or folic acid cycle. Thus the metabolism of Homocysteine involves methionine (which has antioxidant properties) and cysteine (reduces inflammation, is required for normal functioning of liver and aids in communication between the immune cells). While abnormal levels of high Homocysteine can involve certain pathologies. Increased levels of Homocysteine may cause damage to the lining of the arteries and also is found to involve in the formation (triggers) of clots or thrombus (in lungs can cause pulmonary embolism in lungs, stroke in the brain, DVT, DIC etc), leading to blood vessel blockages, therefore the damage to the arteries and blood clot formation significantly increase the risk factor of a heart attack. Chronic, untreated high elevated levels of Homocysteine can lead to other complications such as extreme tiredness, Parkinson’s disease, multiple sclerosis, epilepsy, dementia, ataxia, peripheral neuropathy, microcephaly, developmental delay in children, scoliosis, anaemia, depression, attention deficit hyperactivity disorder, heart diseases or cardiovascular diseases, atherosclerosis, aortic aneurism, osteoporosis, abnormal bone structure, end-stage renal disease, hypothyroidism, ocular manifestations like dislocation of the lens of the eyes, preeclampsia in pregnancies etc. Homocysteine test may be used to screen for diagnosis of vitamin deficiencies such as Vitamin -B6 (pyridoxine), Vitamin –B12 (cobalamin) and Vitamin –Folate/Folic acid. A homocysteine screening test may also aid in the detection of homocystinuria (a rare inherited disorder of protein metabolism which presents with serious health problems since childhood) and patients with high risk for heart diseases (due to high stress - the Homocysteine levels also increase proportionately; probably by atherosclerosis), stroke etc. Homocysteinuria (also called Cystathione beta-synthase deficiency) is a rare genetic disease where enzymes required for methionine metabolism are absent due to inborn errors of metabolism. Homocysteine test is also a helpful tool in the prognosis (monitoring the treatment) eg. Homocysteine levels are monitored after 8 weeks in the treatment of folate or vitamin B supplements (especially Vitamin B6 and Vitamin B12), because if the Homocysteine levels remain high then the vitamin doses are needed to be increased. This test also helps to diagnose homocysteinuria in newborns and infants. Homocysteine is elevated in patients with kidney diseases, psoriasis, thyroid hormones, medications (methotrexate, antiepileptics) etc. Factors that can modulate the levels of Homocysteine blood levels include ageing, smoking, excessive alcohol and gender (male) etc. Furthermore one of the main reasons for high Homocysteine is mutation in MTHFR (Methylene-Tetra-Hydro-Folate Reductase) gene. Two common variants of MTHFR mutations are C677T and A1208C. Mutation in the MTHFR gene can affect the body’s ability to process amino acids – namely Homocysteine and thus causes Homocysteinemia and Homocysteineuria. Likewise, additionally - modern scientific research suggests that there is a strong correlation between higher levels of homocysteine (hyperhomocysteinemia) and deficiencies in folate in cancer cases. Clinical manifestations of high Homocysteine are pale skin, weakness, fatigue, tingling sensation (pins and needles) in hands and feet or legs, dizziness, mood changes, mouth sores. Other additional tests include conjunction with other metabolites such as methylmalonic acid, acylcarnitines, urine organic acids etc. for the screening of primary and secondary disorders of methionine metabolism.
General Instructions:
Sample Requirement: Specimen - Blood sample collected from the vein. Test Preparation: Fasting Required (8 – 10 hours).
NOTE - Sample for specimen collections may vary based on the patient’s condition/cases according to the patient’s presenting complaints/signs or symptoms:
SPECIMEN REQUIREMENT (Special or Rare Cases) - As instructed and guided by Physician / Clinician / Pathologist / as per Laboratory’s requirements, according to procedures and protocols.
This Multi-Specialty Clinical Referral Laboratory RT DIAGNOSTICS provides precise and accurate tests with an extensive range of testing services to the medical centres to help in the diagnosis and identification of pathology in the test specimens for infectious diseases and also to evaluate the function of organ systems of the patient. It prevents further complications and helps to stabilize and restore health to near normalcy at the earliest without delay.
