肾病综合征患儿血清骨保护素改变及糖皮质激素对其的影响

Serum osteoprotegerin level in children with nephrotic syndrome and the effect of glucocorticoid on it

摘要:

目的：观察肾病综合征（nephrotic syndrome, NS）患儿骨保护素改变及糖皮质激素治疗对骨保护素的影响，探讨骨保护素在NS骨代谢改变中的应用价值。方法：随机选取NS患儿44例，其中NS初发患儿24例，糖皮质激素治疗减量过程中复发患儿20例，其糖皮质激素累积剂量为28327±5879 mg/m2；23例年龄性别匹配的正常儿童设为对照组。采用酶联免疫吸附法测定血清骨保护素浓度，采用电化学发光免疫法测定血清骨钙素N端中分子片段（骨钙素N-MID）含量。结果：初发NS组血清骨保护素、骨钙素N-MID含量分别为 211±55 ng/L、46±14 ng/mL，均明显低于对照组（分别为470±57 ng/L、73±9 ng/mL）（P<0.05）。NS复发组血清骨保护素、骨钙素N-MID含量均较NS初发组及对照组低，分别为176±42 ng/L、29±10 ng/mL（P<0.05）。结论：NS患儿本身即存在骨代谢异常，大剂量应用糖皮质激素后可进一步加重骨代谢改变，提示NS患儿骨保护素改变受疾病本身及糖皮质激素治疗的双重影响，骨保护素有望成为预测NS患儿骨代谢改变的新型生化指标。

Abstract:

OBJECTIVE: To observe serum osteoprotegerin (OPG) level in children with nephrotic syndrome (NS) and changes in serum OPG level after glucocorticoid therapy, with the aim of studying the role of OPG in the bone metabolism of children with NS. METHODS: Forty-four children with idiopathic NS were randomly selected as the study group, including 24 newly diagnosed, untreated patients and 20 who had relapsed during the process of glucocorticoid reduction (cumulative dose of glucocorticoid 28327±5879 mg/m2). Twenty-three age- and sex-matched healthy children served as the control group.Serum osteoprotegerin (OPG) level was measured using ELISA. Serum N-terminal midfragment of osteocalcin (N-MID osteocalcin) was determined using electrochemical luminescence immunoassays (ECLIA). RESULTS: Serum levels of OPG (211±55 ng/L) and N-MID osteocalcin (46±14 ng/mL) in the untreated NS group were reduced compared with 470±57 ng/L (OPG) and 73±9 ng/ml (N-MID osteocalcin) in the control group (P<0.05). Serum levels of OPG (176±42 ng/L) and N-MID osteocalcin (29±10 ng/mL) in the NS relapsed group were lower than in the untreated NS and control groups (P<0.05). CONCLUSIONS: Bone metabolism disorders are found in children with NS. High-doses of glucocorticoid therapy can aggravate these disorders. Serum OPG levels in children with NS may be affected by both the renal disease itself and steroid therapy, suggesting that OPG is expected to become a new biochemical indicator for predicting changes to the bone metabolism of children with NS.