With the aging of the population, osteoporosis is becoming more common. It is characterized by a decrease in the matrix and mineral content of bone. This results in a decrease in bone density and consequently, weakness of the bone.

Clinically, the condition is usually asymptomatic. But it may present as boneache of varying degrees of severity, and even spontaneous fracture may occur. There are multiple factors which contribute to osteoporosis. The risk factors include age, women who are post-menopausal, hormonal excesses (parathyroid, thyroid, adrenal), malignancy, alcohol intake, smoking, dietary deficiency, lack of exercise, etc. The detection of osteoporosis can be established by means of bone densitometry.

Recent advances in laboratory technology have enable tests to be available which can assist in the identification of patient at risk of developing osteoporosis, and in monitoring anti-resorptive therapy. Bone tissue in the body is continually being renewed. The renewal process involves the degradation of existing bone matrix. This is accomplished via bone resorption by osteoclasts. At the same time, new bone matrix is being formed by osteoblasts. These cells synthesize type 1 collagen which makes up of over 90% of bone matrix.

The B-CrossLaps assay is specific for the detection of degraded type 1 collagen fragments. Elevated levels of such fragments indicate increased bone resorption. It is also used in monitoring the efficacy of antiresorptive therapy.

Osteocalcin is the most important non-collagen calcium-binding protein in bone matrix. It is produced by osteoblasts during bone synthesis, and is used as marker for bone turnover. Its level in the blood is related to the rate of bone turnover in various bone disorders (osteoporosis, hyperparathyroidism, Paget’s disease). It is therefore used to monitor therapy with antiresorptive agents

骨质疏松症的检查标志

随着人口老化，骨质疏松症变得越来越普遍。它的特证是骨骼中的基质和 矿物质含量减少，这导致骨密度降低，随之而来的是骨骼变得脆弱。

临床上，这种状况通常是无症状的，但它也可以表现为不同程度的骨痛， 甚至可以发生自发性骨折。这些危险因素包括年龄增长，绝经期后的妇 女，激素过多（甲状旁腺素，甲状腺素，肾上腺素）恶性肿瘤，酗酒，吸 烟，饮食不足，缺乏锻练等。骨密度测定可以检测骨质疏松症。

目前实验技术的发展可以帮助鉴定患者发生骨质疏松症的危险程度，并且 监测抗吸收疗法。

人体内的骨组织处于持续更新状态。这种更新过程涉及现有骨质的退化。 这是由破骨细胞吸收骨骼所引起的。同时，成骨细胞形成新的骨基质。成 骨细胞合成构成90％以上骨基质的1型胶原蛋白。

B-特殊胶原序列测定是专门用于检测降解的1型胶原蛋白片段。这些片段 含量增高表明骨吸收的增加。这有助于鉴定有骨质疏松危险的病人。它也

可以用于监测抗吸收治疗的疗效。