الوصف
Homocysteine is a normal metabolite of the essential amino acid methionine. Its metabolism is driven by Vitamin B2, B6, B12, and folate. Deficiencies in Vitamin B complex and folate or mutations in the methylenetetrahydrofolate (MTHFR) gene can lead to hyperhomocysteinaemia. Homocysteine can undergo autooxidation, resulting in the formation of reactive oxygen species and it may limit the bioavailability of nitric oxide, resulting in the impairment of flow-mediated vasodilatation. It also has procoagulant activity due to impairment of tissue plasminogen function. Altogether, these interactions can lead to vascular tissue damage, thus increasing risk of cardiovascular disease.
دواعي الإستعمال
Moderate homocysteinemia is associated with increased risk for cardiovascular disease, atherosclerosis, and thromboembolism. Endstage renal disease is associated with moderate hyperhomocysteinemia whereas homocystinurias, rare inborn errors of homocysteine metabolism, are associated with severe hyperhomocysteinemia. Measurement of homocysteine level is also useful in the evaluation of hypercoagulable states. Normally, homocysteine levels increase with age.
نوع العينة والكمية والشروط
1 ml Serum 1 ml K2, K3-EDTA or Li-Heparin Plasma Stability: 4 Days at 15-25 °C 4 Weeks at 2-8 °C
إحتياطات خاصة
Centrifuge blood samples immediately or keep the samples on ice and centrifuge within an hour of collection. Fasting specimen is preferred. Avoid haemolysed, turbid, and severly lipemic specimens. Folic acid intake affects the result.
المعدل الطبيعي
Folate Non-supplemented: Children < 15 Years: Up to 10 µmol/L Adults 15-65 Years: Up to 15 µmol/L Elderly > 65 Years: Up to 20 µmol/L Folate Supplemented: Children < 15 Years: Up to 8 µmol/L Adults 15-65 Years: Up to 12 µmol/L Elderly > 65 Years: Up to 16 µmol/L
