血浆离子钙和总钙测定对肿瘤性高钙血症的诊断意义

目的 分析血浆中离子钙(ICa)与总钙(TCa)测定在诊断肿瘤性高钙血症中的临床价值.方法 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(肿瘤组)和44例健康体检者(对照组)血浆中的ICa和TCa进行检测,同时检测白蛋白(Alb)及pH值,计算校正总钙(cTCa)和校正离子钙(nICa),统计有关指标.结果 两组cTCa、ICa及nICa比较差异有统计学意义(P＜0.01),但TCa比较差异无统计学意义(P＞0.05).以cTCa＞2.70 mmol/L,nICa＞1.35 mmol/L为高钙血症判断临界值,则肿瘤组nICa阳性率高于cTCa,分别为18.18%(14/77)和6.49%(5/77),差异有统计学意义(P=0.023).结论 在肿瘤性高钙血症的诊断中,ICa具有较高的临床价值,可提高肿瘤性高钙血症的诊断率.

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

Objective To evaluate the clinical significance of plasma ionized calcium (ICa) and total calcium (TCa) measurement in diagnosis of tumor-associated hypercalcemia. Methods The heparin lithium anticoagulated plasma were collected and measured with ion selective electrode (ISE) and orthocresolphthalein complexone (OCPC) method for ICa and TCa in 77 patients with malignant tumor (tumor group) and 44 healthy controls (control group). Meanwhile,plasma albumin and pH value were measured to correct TCa (cTCa) and ICa(nICa). The results were analyzed. Results The levels of cTCa,ICa and nICa in tumor group were significantly higher than those in control group(P＜ 0.01 ) ,but there was no significant difference of TCa between two groups (P ＞ 0.05 ). cTCa ＞ 2.70 mmol/L, nICa ＞ 1.35 mmol/L as the hypercalcemia eritical value, the positive rate of nICa and cTCa were 18.18% (14/77) and 6.49% (5/77)respectively,the difference was significant (P = 0.023). Conclusion Determination of ICa may be more clinical meaningful than TCa for tumor-associated hypercalcemia.