Evaluation of the Measurement of Lysate Homocysteine in Patients with Symptomatic Arterial Disease and in Healthy Volunteers

Because of the increasing interest in routine clinical measurement of plasma total homocyst(e)ine (tHcy), it is necessary to simplify the critical preanalytical phase, especially the centrifugation step required immediately after blood collection to separate homocysteine-producing and -releasing blood cells from plasma (1)(2)(3)(4). To overcome this procedural problem, which leads to falsely increased tHcy results when sample transport is prolonged, we recently developed a blood collection system that stabilizes tHcy in lysed whole blood (lysHcy) for at least 2 days at room temperature without requiring a centrifugation step (5). Because of the dilution with plasma with intracellular liquid, the lysHcy concentrations measured in the lysate system are lower than the homocysteine concentrations measured in the tHcy system; therefore, the aim of the present study was to evaluate the measurement of lysHcy in patients with symptomatic arterial disease and healthy volunteers, using the determination of tHcy as a reference method. tHcy and lysHcy determinations were compared with multiple linear regression analysis, taking into account age, and the concentrations of creatinine, folate, and vitamin B12.We studied 224 consecutive patients (139 men and 85 women; ages 35–93 years) admitted for surgical repair of arterial disease, including 73 patients with high-grade carotid stenosis as classified by ultrasound and angiography according to the criteria of the European Carotid Surgery Trialists’ study group (6) and 27 male patients presented with abdominal aortic aneurysm with a maximum diameter exceeding 5 cm. Peripheral arterial occlusive disease (PAOD) was present in 124 patients, 59 of whom suffered from rest pain or gangrene. Healthy volunteers (33 males and 58 females; ages 8–82 years) were recruited mainly from employees of our hospital and reported no history of PAOD, heart disease, diabetes, thrombosis, cerebrovascular disease, or renal impairment. Their routine blood analyses, including hematological …