血浆总钙和离子钙测定对肿瘤性高钙血症的诊断意义

Clinical significance of plasma total calcium and ionized calcium measurement in diagnosis of tumor-associated hypercalcemia

目的探讨肿瘤患者血浆中离子钙(ICa)与总钙(TCa)测定在诊断肿瘤性高钙血症中的临床应用价值。方法收集肝素锂抗凝血浆,分别采用离子选择电极法及邻甲酚酞络合酮法对77例恶性肿瘤患者和44例健康对照者血浆中的ICa和TCa进行检测,同时检测清蛋白(ALB)及pH值,计算校正总钙(cTCa)和校正离子钙(nI-Ca),统计有关指标。结果与健康对照组相比,恶性肿瘤患者血浆中的cTCa浓度、ICa及nICa水平显著升高,差异有统计学意义(P<0.01),但TCa水平差异无统计学意义(P>0.05)。以cTCa>2.70mmol/L,nICa>1.35mmol/L为高钙血症判断临界值,则nICa升高阳性率高于cTCa,分别为18.19%(14/77)和6.49%(5/77),差异有统计学意义(P<0.05)。结论在肿瘤性高钙血症的诊断中,ICa具有较高的临床价值,可提高高钙血症的诊断率。

Objective To evaluate the clinical significance of plasma total calcium （TCa） and ionized calcium （ICa） measurement in diagnosis of tumor-associated hypercalcemia. Methods The heparin lithium anticoagulated plasma were collected and were measured with ion selective electrode （ISE） and O-cresolphthalein complexone （OCPC） method for TCa and ICa in 77 patients with malignant tumor （malignant tumor group） and 44 healthy controis （healthy control group）. Meanwhile, plasma p H value and albumin were measured to correct TCa and ICa. The results were statistically analyzed. Results The levels of cTCa,ICa and nICa in malignant tumor group were significantly higher than that in healthy control group （P〈0.01）, but there was no significant difference of TCa between the two groups （P〈0.05）. The positive rate of nlCa and cTCa were 18.19%（14/77） and 6.49% （5/77） respectively,the difference was significant （P〈0.05）. Conclusion Determination of ICa may be more clinical meaningful than TCa to tumor-associated hypercalcemia.