Discordant results of CK-MB and troponin I measurements: a review of 14 cases

In the course of a clinical comparison involving 204 parallel total creatine kinase (CK), creatine kinase-MB isoenzyme (CK-MB), and cardiac troponin I (cTnI) measurements, 12 patients were identified in whom cTnI was elevated while total CK was normal, as well as 2 patients in whom CK-MB was elevated while cTnI was normal. CK-MB relative index was elevated in 6 of the twelve cTnI-positive patients with normal total CK; only 2 of these patients had a discharge diagnosis of acute myocardial infarction (AMI). All of the 12 patients in this group had medical conditions that are associated with greater risk for acute cardiac events. Both patients with normal cTnI but elevated total CK and CK-MB index had chronic renal insufficiency; one of these patients had a positive stress test and a diagnosis of AMI. The other cTnI-negative patient died 2 days after admission, and autopsy revealed evidence of ischemic changes, but not acute infarction. Significant differences were apparent between traditional CK-MB results and cTnI measurements. Using total CK elevation as a prerequisite for subsequent CK-MB measurement may limit the clinical sensitivity of this enzyme marker for detecting subacute ischemic damage to the myocardium. Elevated total CK and CK-MB isoenzyme without corresponding elevations in cTnI, on the other hand, may reflect changes in enzyme elimination kinetics due to renal failure, or cross-reactivity of the cTnI assay with non-cardiac antigens.     

Circulating CK-MB and CK-BB isoenzyme after gastrointestinal surgery.

The effect of gastrointestinal surgery on serum creatine kinase activity was studied in 30 patients. The MB isoenzyme was demonstrated in sera of 30% of the patients and BB isoenzyme in 23%. MB content varied from 0.8 to 10.3% of the total creatine kinase activity, and the BB content from 0.6 to 18.4%. The CK-BB was probably of gastrointestinal origin, since gastrointestinal tract contains high CK activity with BB isoenzyme predominating. A cardiac origin for the observed serum CK-MB isoenzyme increase would seem the most likely, although no patients showed evidence of electrocardiographic changes. Increased CK-MB activity has been observed in myocardial ischaemia without infarction.     

Cardiovascular risk markers in hemodialysis patients

Cardiovascular events are the main cause of death in hemodialysis patients. Nevertheless, acute myocardial infarction may be misdiagnosed in uremic patients, because typical markers have a high rate of false positivity. A recent two-year prospective study showed that predialytic high serum concentrations of troponin T and CK-MB mass were associated with high mortality, cardiac mortality, myocardial infarction and unstable angina (MACEs). We studied 16 uremic patients (13 M; 3 W) on standard HD and 6 patients (4 M; 2 W) on on-line HDF, who had been taking folic acid for at least three months. Patients who suffered from acute or chronic cardiac ischemic disease were excluded. Anthropometric parameters, pre and post-dialytic pH, HCO3 and electrolytes did not differ between the two groups. Kt/V and URR% were lower in conventional HD vs on-line HDF (p < 0.04; p < 0.04). ORR% was strongly elevated in on-line HDF compared with HD (p < 0.005). In conventional HD, ORR% was directly correlated with Kt/V and URR% (r = 0.49, p < 0.04; r = 0.48, p < 0.04, respectively). Even in on-line HDF ORR% was directly correlated with Kt/V and URR% (r = 0.79, p < 0.04; r = 0.76, p < 0.05, respectively). Troponin I and CK-MB mass were not significantly different in pre vs post-dialysis, both in standard HD and on-line HDF. Nevertheless, in standard HD postdialytic troponin I correlated with serum sodium concentration (r = 0.93, p < 0.000), potassium (r = 0.67, p < 0.004) and serum chlorine (r = 0.92, p < 0.92, p < 0.000). CK-MB mass showed a correlation with serum chlorine (r = 0.49, p < 0.05). Postdialytic CK-MB mass correlated with serum potassium in on-line HDF (r = 0.83, p < 0.03). Our data suggest that hemodialytic treatments, both standard HD and on-line HDF, do not modify serum troponin I and CK-MB mass. Consequently, we can use these parameters for the diagnostic approach in acute or chronic ischemic heart disease in hemodialysis patients.     

急性心肌梗死患者务清肌钙蛋白T和C反应蛋白变化及其意义

目的：评价血汪肌钙蛋白T（TnT）和C反应蛋白（CRP）在急性心肌梗死（AMI）和不稳定型心绞痛（UAP）的早期诊断及预后评价。方法：分析了AMI48例，UAP45例及健康对照36人血清CRP、TnT、肌酸激酶（CK）和同工酶（CK－MB）水平，并对结果行配对χ^2检验。结果：AMI组入院时血清CRP和TnT阳性率分别为81．3％和97．9％，均明显高于同时间CK和CK－MB的阳性率（p均＜0．01）；UAP组血清CRP、TnT、CK及CK－MB阳性率分别为42．2％、13．3％、11．1％及6．7％。健康对照组36例四项指标均无1例阳性。结论：TnT和CRP在早期辅助诊断AMI和评估UAP患者预后中有应用价值，CK、CK－MB和CRP、TnT联合测定可以提高对AMI诊断的准确性。     

Positive troponin T without cardiac involvement in inclusion body myositis

Cardiac troponin T (cTnT) is considered as a specific marker for acute myocardial infarction. Here, we present a case with elevated cTnT, determined by a third-generation assay, without signs of a myocardial lesion. Routine investigation of a 66-year-old female patient with indolent B-cell lymphoma revealed increased serum levels of creatine kinase (CK), MB fraction of CK (CK-MB), and cTnT, although she did not complain of cardiac symptoms. Electrocardiographic monitoring, echocardiography, magnetic resonance computed angiography, and percutaneous coronary angiography excluded myocardial damage. However, the close follow-up showed a steady increase of CK-MB and cTnT levels and gradual development of weakness in both thighs. A biopsy of the right quadriceps muscle led to the diagnosis of inclusion body myositis. In contrast to cTnT, cardiac troponin I could not be detected retrospectively in any of her serum samples. These results demonstrate for the first time that cTnT is elevated in patients with inclusion body myositis.     

快速固相免疫层析法测定心肌肌钙蛋白I及在AMI诊断中的应用

为探讨采用快速固相免疫层析法测定心肌肌钙蛋白Ⅰ(cTnI) 和选择性免疫抑制紫外法测定肌酸激酶同工酶(CK-MB)及在急性心肌梗死(AMI) 诊断中的价值,本文分别对52例AMI患者于胸痛发生后4、8、12、24、48h及第5、7d和26名正常对照者的血清进行了cTnI及CK-MB 的测定.结果表明,AMI组血清cTnI、CK-MB 的测定值均明显高于正常对照组,具有显著性差异(P<0.01 );AMI患者cTnI在4h及第5、7d时的阳性率均明显高于CK-MB,具有显著性差异(P<0.01 ).以上数据表明,cTnI在诊断急性心梗中具有较高的灵敏度及高度特异性,尤其是采用快速固相免疫层析法检测cTnI,可为快速诊断AMI提供依据,具有临床应用价值.     

Myocardial infarction and histamine release

On the basis of previous data suggesting the involvement of cardiac histamine in ischemic heart disease (IHD), we evaluated plasma histamine (H) and creatine-kinase isoenzyme (CK-MB) level in cardiac and healthy subjects.20 patients with acute myocardial infarction (AMI) (10 developing AMI in Hospital, thus making possible the detection of plasma H level before acute event), 10 patients with IHD not developing AMI and 10 presumably healthy subjects were admitted to the study.15 of all patients with AMI showed a correlated H and CK-MB trend during AMI reaching the highest peak 24 hours after onset of pain.7 of the patients with IHD who developed AMI in Hospital showed a slightly higher plasma H level, before AMI, than those with IHD who did not develop AMI.A possible role of histamine in the pathogenesis of AMI is discussed.     

血清心肌型脂肪酸结合蛋白快速检测急性心肌梗死的敏感度和特异度分析

目的:分析血清心肌型脂肪酸结合蛋白(H-FABP)快速检测对急性心肌梗死(AMI)早期诊断的敏感度和特异度。方法:53例胸痛患者,经确诊分为AMI组(包括发病<6h和6～12h两亚组)和非AMI组,平行检测H-FABP、肌红蛋白(MYO)、心肌肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB),计算H-FABP等指标诊断AMI的敏感度和特异度。结果:H-FABP诊断发病<6h AMI的敏感度为85.71%,与MYO的80.95%相近,明显高于cTnI的47.62%和CK-MB的52.38%,差异有统计学意义(P<0.05);AMI发病6～12h,H-FABP诊断AMI的敏感度为100.00%,略高于MYO、cTnI和CK-MB(均为92.86%),但差异无统计学意义(P>0.05)。H-FABP等指标诊断AMI的特异度无论非AMI组还是健康对照组,各指标间差异均无统计学意义(P>0.05)。结论:H-FABP对AMI早期诊断有较高的敏感度和特异度,可作为AMI早期筛查及诊断指标。     

传统心肌酶谱联合损伤相关蛋白IMA、TnI-Ultra检测对急性心肌梗死早期诊断的价值分析

目的 探讨肌酸激酶(CK)、肌酸激酶同功酶(CK-MB)、同型半胱氨酸(HCY)和乳酸脱氢酶(LDH)等心肌酶,联合血清缺血修饰清蛋白(IMA)和超敏肌钙蛋白I(TnI-Ultra)等心肌损伤相关蛋白检测在急性心肌梗死(acute myocardial infarction,AMI)早期诊断中的应用.方法 选取我院于2014年1月至2017年1月期间收治的AMI患者150例,病发后6h内采集静脉血,检测患者心肌酶谱(CK、CK-MB、HCY和LDH)及IMA和TnI-Ultra等生化指标.同期选取100例非AMI患者血液样本作为对照组.结果 150例AMI患者血清CK、CK-MB、LDH(U/L)和HCY(μmol/L)水平分别为:688.5±68.7、86.4±9.2、364.7±55.2和34.5±9.4.与对照组相比,CK和CK-MB水平明显升高(P<0.01),而LDH和HCY与对照组相比差异无统计学意义(P>0.05),但IMA(65.5±11.7 U/L)和TnI-Ultra(10.6±3.5μg/L)水平均明显升高,差异有统计学意义(P<0.01).结论 CK、CK-MB、HCY和LDH等心肌酶指标在AMI患者中有较高的阳性率,但某些非AMI类疾病也可能导致以上指标异常升高;IMA和TnI-Ultra等心肌损伤相关蛋白对AMI诊断有较高的特异性.心肌酶联合心肌损伤相关蛋白检测有助于AMI的早期诊断,对降低AMI风险具有重要意义.     

Total creatine kinase and isoenzyme fractions in chronic dialysis patients

We measured total serum creatine kinase (CK) and serum creatine kinase MB fraction (CK-MB) in 53 patients on continuous ambulatory peritoneal dialysis (CAPD) and 52 patients on maintenance hemodialysis (HD), using Scalva UV methodology for CK and electrophoresis for CK-MB. Seven of the 53 CAPD patients (13%) had an elevated total CK, and only one of these 7 patients had an elevated CK-MB greater than 5%. In contrast 22 HD patients (42%) had increased total CK values, and 6 of these 22 HD patients (27%) showed elevated CK-MB isoenzyme greater than 5%. For each sex, blacks had higher mean CK values than whites. Twenty-one out of the 43 HD patients who received intramuscular injections had elevated total CK values and 6 of these 21 patients had elevated CK-MB isoenzyme independent of the timing of injection. The increased frequency of higher total CK values in HD patients appears to be related to race and androgen administration. The modest elevations in CK-MB fraction (5 to 8%) in these patients require careful interpretation.     

血浆cTnI、CK-MB及BNP水平在急性胸痛患者中的变化及临床意义

目的探究血浆心肌肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)、脑钠肽(BNP)水平在急性胸痛患者中的变化及临床意义。方法选择2016年1月至2019年1月我院收治的以急性胸痛为首发症状的患者作为研究对象,其中急性心肌梗死(AMI)患者59例,不稳定心绞痛(UAP)患者42例,稳定型心绞痛(SAP)患者38例,另39例患者经检查冠脉未见明显异常,纳入对照组。收集患者临床资料,采用GRACE评分工具进行危险分级,测定血浆cTnI、CK-MB及BNP水平。结果SAP、UAP、AMI组患者高脂血症患病率显著高于对照组(P<0.05),左心射血分数(LVEF)显著低于对照组(P<0.05),血浆cTnI、CK-MB、BNP水平高于对照组(P<0.05);ROC曲线示,血浆cTnI、CK-MB、BNP指标诊断心源性胸痛的曲线下面积分别为0.834、0.792、0.892,各指标联合诊断的曲线下面积为0.935;随着危险程度的升高,血浆cTnI、CK-MB、BNP水平升高(P<0.05);Pearson相关性分析示,血浆cTnI、CK-MB、BNP与LVEF呈负相关(P<0.05),与冠脉病变支数、GRACE评分呈正相关(P<0.05)。结论心源性胸痛患者可出现血浆cTnI、CK-MB、BNP等水平的升高,且升高幅度与病情严重程度相关,临床上可将其作为诊断高危性缺血性疾病的参考指标。     

Misdiagnosis of acute myocardial infarction

A total of 979 cardiac profiles were reviewed. Seventeen cases were found to have elevated CK-BB by electrophoresis and were misidentified by the immunoinhibition/immunoprecipitation technique as elevated creatine phosphokinase (CK-MB). Eleven of the 17 cases also had elevated lactate dehydrogenase (LD) LD-5/LD-1 ratio; five cases were motor vehicle accident (MVA), four cases were prostatic carcinoma (PC), and one case each of breast carcinoma and coronary heart disease. One case of PC and one of MVA with a preliminary clinical diagnosis of acute myocardial infarction (AMI) were presented. Our findings underscore the importance of electrophoretic confirmation of the presence of CK-MB when detected by a quantitative technique. Clinicians should consider the possibilities of PC or other cancers when elevated "CK-MB" is present in conjunction with a raised LD-5/LD-1 ratio in patients who fail to show clear-cut clinical evidence of AMI. The mechanism of elevated CK-BB and LD-5/LD-1 ratio in PC patients are discussed.     

Diagnosis of acute myocardial infarction from sequential enzyme measurements obtained within 12 hours of admission to hospital.

A prospective study was made of sequential changes in serum creatine kinase (CK) and CK-MB isoenzyme activity within the 12 hours following admission to the coronary care unit on 65 patients with recent chest pain. CK determinations were performed in the laboratory or in the coronary care unit using a dry reagent strip analyser. Slope values for log CK/hour and log CK-MB/hour were calculated, used to confirm or exclude the diagnosis of myocardial infarction, and compared with diagnosis by conventional means. Compared with retrospective diagnosis using all available information, the CK slope had a sensitivity of 100% and a specificity of 94%. This compared with a sensitivity of 94% and specificity of 90% for diagnosis using upper reference limits alone. Determination of CK slope permits very rapid and accurate biochemical confirmation or exclusion of myocardial infarction and the possibility of performing the measurements on the coronary care unit. It additionally offers the prospect of major cost savings resulting from early discharge or transfer from the coronary care unit.     

非ST段改变的急性心肌梗死临床分析

目的 探讨非ST段改变的急性心肌梗死患者冠状动脉病变情况,指导进一步治疗。方法 选取我院2013年12月~2018年12月因胸闷、胸痛不适入住苏州高新区人民医院、新疆自治区人民医院的患者76例,入院行心电图未见相关导联ST段改变,动态观察心电图及血清超敏肌钙蛋白T、肌酸激酶同工酶,多次复查未发现心电图有动态改变,但血清超敏肌钙蛋白、肌酸激酶同工酶数小时,甚至更长时间开始升高,急诊行冠状动脉造影术（CAG）,观察有无冠状动脉急性闭塞或次全闭塞,同时观察病变冠脉血管的部位、内径。结果 纳入的76例心电图无ST段改变,但数小时后血清心肌标志物升高的胸闷、胸痛患者行冠状动脉造影术发现:冠状动脉急性闭塞或次全闭塞的患者占94.74%,比例较高,多见于钝缘支,占78.95%,且冠脉血管内径均＞1.5 mm。结论 除了ST段抬高和ST段压低的急性心肌梗死,非ST段改变的急性心肌梗死也常常出现在临床当中,对此类不典型的患者,早期识别很重要,及时有效的处理,预后良好。     

甲状腺功能异常患者心肌酶变化的分析

为了解原发性甲状腺功能减退症（甲减）患者和甲状腺功能亢进（甲亢）患者心肌酶的变化,检测了20例原发性甲减患者、27例甲亢患者以及30例健康体检者（对照组）的空腹血清天门冬酸氨基转移酶（AST）、肌酸激酶（CK）及其同工酶（CK-MB）、乳酸脱氢酶（LDH）及其同工酶（HBDH）、FT3、FT4、TSH、总胆固醇（Tch）。结果显示,原发性甲减患者AST、CK、CK-MB、LDH、HBDH及Tch均明显高于对照组（P分别〈0.01、0.01、0.01、0.01、0.05、0.01）;TSH和FT4与心肌酶、Tch均无相关性;FT3与CK、CK-MB负相关（r=-0.53,-0.47,P均〈0.05）,与Tch呈负相关（r=-0.504,P〈0.05）;甲亢患者血清CK-MB明显高于对照组（P〈0.01）,且血清FT4与CK-MB呈显著正相关（r=0.462,P〈0.01）。结论：原发性甲减患者和甲亢患者常伴心肌酶升高,其中甲减者FT3水平与CK、CK-MB、Tch升高关系更密切。     

High creatine kinase MB concentration and activity in patients with rhabdomyosarcoma

A 14-year-old boy with rhabdomyosarcoma (RMS) of the left palm showed increased concentration and activity of creatine kinase (CK; EC 2.7.3.2) MB in his serum. CK isoenzyme analysis revealed no extra band. Other laboratory data including high lactate dehydrogenase (LD) isoenzyme 2, CK isoenzyme BB and MB, neuron specific enolase (NSE), and clinical findings did not support the diagnosis of myocardial infarction. The high activity and concentration of CK-MB in serum is possibly originated from the tumor. We could follow his time-course and analyze laboratory data of him and other 6 patients with RMS. We concluded that CK-MB, both concentration and activity, was the more sensitive marker of disease states of RMS than NSE and LD to follow up the patients with RMS.     

Increased circulating macrophage migration inhibitory factor levels are associated with coronary artery disease

BACKGROUND:

To evaluate the macrophage migration inhibitory factor and E-selectin levels in patients with acute coronary syndrome.

MATERIALS/METHODS:

We examined the plasma migration inhibitory factor and E-selectin levels in 87 patients who presented with chest pain at our hospital. The patients were classified into two groups according to their cardiac status. Sixty-five patients had acute myocardial infarction, and 22 patients had non-cardiac chest pain (non-coronary disease). We designated the latter group of patients as the control group. The patients who presented with acute myocardial infarction were further divided into two subgroups: ST-elevated myocardial infarction (n = 30) and non-ST elevated myocardial infarction (n = 35).

RESULTS:

We found higher plasma migration inhibitory factor levels in both acute myocardial infarction subgroups than in the control group. However, the E-selectin levels were similar between the acute myocardial infarction and control patients. In addition, we did not find a significant difference in the plasma migration inhibitory factor levels between the ST elevated myocardial infarction and NST-elevated myocardial infarction subgroups.

DISCUSSION:

The circulating concentrations of migration inhibitory factor were significantly increased in acute myocardial infarction patients, whereas the soluble E-selectin levels were similar between acute myocardial infarction patients and control subjects. Our results suggest that migration inhibitory factor may play a role in the atherosclerotic process.     

主动脉内球囊反搏联合血栓抽吸术治疗大面积ST段 抬高型急性心肌梗死的疗效观察

目的 研究主动脉内球囊反搏联合血栓抽吸术对大面积ST段抬高型急性心肌梗死患者心功能及预后的影响,观察其临床疗效。方法 选取2016年5月~2017年1月我院大面积ST段抬高型急性心肌梗死患者80例,按照随机抽签方式分为对照组和观察组,各40例。对照组采取予以血栓抽吸术治疗,观察组予以主动脉内球囊反搏联合血栓抽吸术治疗,比较两组术后肺动脉楔压（PCWP）、心输出量（CO）、平均动脉压（MABP）、心肌钙蛋白（CTnI）峰值及肌酸激酶同工酶（CK-MB）峰值水平及心功能改善情况。结果 观察组CO高于对照组,差异有统计学意义（P＜0.05）;观察组MABP高于对照组[（55.38±10.76）mmHg vs （42.79±11.08）mmHg],差异有统计学意义（P＜0.05）;观察组PCWP低于对照组[（9.41±6.65）mmHg vs （18.33±7.56）mmHg],差异有统计学意义（P＜0.05）;CTnI及CK-MB峰值水平观察组均低于对照组[（0.34±0.06）μg/L vs （0.51±0.15）μg/L、（105.19±10.78）U/L vs （151.64±15.72）U/L],差异有统计学意义（P＜0.05）;术后6个月观察组LVEF优于对照组[（43.27±6.37）% vs （39.85±5.96）%],差异有统计学意义（P＜0.05）;术后6个月观察组LVESD、LVEDD水平均低于对照组,差异有统计学意义（P＜0.05）。结论 与血栓抽吸术相比,主动脉内球囊反搏联合血栓抽吸术可进一步改善患者心功能,且预后良好,值得临床应用。     

The prognostic value of serum troponin T in unstable angina.

BACKGROUND. Cardiac troponin T is a regulatory contractile protein not normally found in blood. Its detection in the circulation has been shown to be a sensitive and specific marker for myocardial cell damage. We used a newly developed enzyme immunoassay for troponin T to determine whether its presence in the serum of patients with unstable angina was a prognostic indicator. METHODS. We screened 109 patients with unstable angina (25 with accelerated or subacute angina and 84 with acute angina at rest) for serum creatine kinase activity, creatine kinase isoenzyme MB activity, and troponin T every eight hours for two days after admission to the hospital. The outcomes of interest during the hospitalization were death and myocardial infarction. RESULTS. Troponin T was detected (range, 0.20 to 3.64 micrograms per liter; mean, 0.78; median, 0.50) in the serum of 33 of the 84 patients (39 percent) with acute angina at rest. Only three of these patients had elevated creatine kinase MB activity (two were positive for troponin T, and one was negative). Of the 33 patients who were positive for troponin T, 10 (30 percent) had myocardial infarction (3 after coronary-artery bypass surgery), and 5 of these died during hospitalization. In contrast, only 1 of the 51 patients with angina at rest who were negative for troponin T had an acute myocardial infarction (P less than 0.001), and this patient died (P = 0.03). Thus, 10 of the 11 patients with myocardial infarctions had detectable levels of troponin T; only 1 had elevated creatine kinase MB activity. Troponin T was not detected in any of the 25 patients with accelerated or subacute angina, and none of these patients died. CONCLUSIONS. Cardiac troponin T in serum appears to be a more sensitive indicator of myocardial-cell injury than serum creatine kinase MB activity, and its detection in the circulation may be a useful prognostic indicator in patients with unstable angina.     

Clinical evaluation of the new creatine kinase MB reagent kit "L-System CK-MB MtO"

The creatine kinase MB (CK-MB) activity assay, which is based on the immunoinhibition method, has long been used in the diagnosis of acute myocardial infarction (AMI) because of its good cost-performance ratio and simplicity. However, the immunoinhibition method can not differentiate between CK-MB and MtCK, and therefore, CK-MB activity determined using this method is higher than the actual value in the sample which MtCK appears; this may lead to the misdiagnosis of AMI. We, therefore, evaluated the analytical and clinical performance of a new CK-MB reagent kit "L-System CK-MB MtO," which can inhibit MtCK. The kit yielded good precision and linearity and no interference from hemolysis, bilirubin or chyle. A good correlation was observed between the values determined using this kit and those determined using the conventional kit for samples of patients with acute coronary syndromes. However, differences were observed in the CK-MB values determined for samples from patients with malignancy. CK isoenzyme analysis indicated that MtCK was present in all these samples. The new method permits the accurate estimation of CK-MB activity in samples of patients with high serum levels of MtCK activity and indicates that the conventional method has a high false-positive rate for CK-MB activity. CK-MB activity in the serum of healthy individuals measured using the new and the conventional kits was 1.9-9.5 U/l and 4.5-15.3 U/l, respectively. The new kit, enables accurate estimation of CK-MB activity and is, therefore, more useful than the conventional kit in the diagnosis of acute coronary syndromes.