Green S M, Vowels J, Waterman B, Rothrock S G, Kuniyoshi G
Department of Emergency Medicine, Loma Linda University School of Medicine, CA, USA.
Acad Emerg Med. 1996 Nov;3(11):1034-41. doi: 10.1111/j.1553-2712.1996.tb03350.x.
To determine the test performance of leukocytosis for identifying acute myocardial infarction (AMI) in patients with nondiagnostic ECGs, admitted to rule out AMI.
A retrospective, comparative test performance study was conducted using patients admitted to a university teaching hospital to rule out AMI. Clinical and laboratory information was reviewed and hospital laboratory ranges were used to define threshold elevations: total creatine kinase (CK), 275 U/L; CK-MB, 7.5 micrograms/L ; white blood cell (WBC) count, 11.5 x 10(9)/L; and absolute neutrophil count (ANC), 8.0 x 10(9). Sensitivity, specificity, and predictive values of the total CK, CK-MB, WBC count, and ANC were calculated, and receiver operating characteristic (ROC) curves constructed. Test performances of marker combinations also were determined.
The initial WBC count was significantly higher for the subjects who had AMI (11.1 vs 8.8 x 10(9)/L, p < 0.001). For the 688 subjects who had nondiagnostic ECGs, sensitivities for the initial total CK, CK-MB, WBC, and ANC were 39%, 73%, 35%, and 36%, respectively, while the corresponding specificities were 94%, 93%, 85%, and 86%. Logistic regression analysis confirmed leukocytosis as an independent predictor of AMI (adjusted odds ratio 4.08, 95% CI 1.73-9.63). While CK-MB alone was 73% sensitive for AMI, the decision rule of either an elevated CK-MB or an elevated WBC count increased this sensitivity to 88% (corresponding specificity 79%). Similarly, while CK-MB alone was 93% specific for AMI, the combination of an elevated CK-MB and an elevated WBC count increased this specificity to 99% (corresponding sensitivity 20%).
Leukocytosis is significantly associated with AMI, and is a weak but independent laboratory predictor of this condition. In this preliminary study of admitted patients suspected of AMI, the combination of the WBC and the CK-MB may have additional diagnostic value over an isolated CK-MB result. Neither parameter in isolation was satisfactorily sensitive for AMI. Prognostic assessment of the role of the WBC count in clinical decision making should address its complementary role to that of other clinical and ancillary test parameters.
确定白细胞增多症对于排除急性心肌梗死（AMI）而入院且心电图无诊断意义的患者中识别AMI的检测效能。
采用一所大学教学医院收治的排除AMI的患者进行一项回顾性比较检测效能研究。回顾临床和实验室信息，并使用医院实验室范围来定义阈值升高：总肌酸激酶（CK）275 U/L；CK-MB 7.5微克/L；白细胞（WBC）计数11.5×10⁹/L；绝对中性粒细胞计数（ANC）8.0×10⁹。计算总CK、CK-MB、WBC计数和ANC的敏感性、特异性及预测值，并构建受试者工作特征（ROC）曲线。还确定了标志物组合的检测效能。
发生AMI的受试者初始WBC计数显著更高（11.1对8.8×10⁹/L，p<0.001）。对于688例心电图无诊断意义的受试者，初始总CK、CK-MB、WBC和ANC的敏感性分别为39%、73%、35%和36%，而相应的特异性分别为94%、93%、85%和86%。逻辑回归分析证实白细胞增多症是AMI的独立预测因素（校正比值比4.08，95%CI 1.73 - 9.63）。虽然单独CK-MB对AMI的敏感性为73%，但CK-MB升高或WBC计数升高的决策规则将该敏感性提高至88%（相应特异性79%））。同样，虽然单独CK-MB对AMI的特异性为93%，但CK-MB升高和WBC计数升高的组合将该特异性提高至99%（相应敏感性20%）。
白细胞增多症与AMI显著相关，是该病症的一个微弱但独立的实验室预测因素。在这项对疑似AMI的入院患者的初步研究中相比单独的CK-MB结果，WBC和CK-MB的组合可能具有额外的诊断价值。单独任何一个参数对AMI的敏感性均不令人满意。在临床决策中对WBC计数作用的预后评估应考虑其与其他临床及辅助检查参数的互补作用。
