title: Effect of macro-creatine kinase and increased creatine kinase BB on the rapid diagnosis of patients with suspected acute myocardial infarction in the emergency department.
abstract: Although there are more sensitive and earlier diagnostic markers for the diagnosis of acute myocardial infarction (AMI), measurement of creatine kinase (CK) MB isoenzyme (CKMB) using the immunoinhibition method is still widely used in stat laboratories. In this study, 3,290 patients with the prediagnosis of AMI underwent physical examinations, electrocardiography, and repetitive measurements of CK, CKMB activity, and CKMB mass, and 304 of them were diagnosed as having AMI. Electrophoresis of CK and CKMB mass was performed for the samples from 415 patients whose CKMB activity values were found to be increased and were not correlated with total CK levels. According to CKMB activity, CK electrophoresis, and CKMB index (100 x CKMB activity/CK) values, macro-CK (MCK) and/or increased CKBB levels were detected in 27 cases (MCK-I in 10 cases, MCK-II in 9, increased CKBB in 5, and both MCK-II and increased CKBB in 3). CKMB activity was found to be increased for all except one patient (96.3%), and the CKMB index was >25% in 25 (92.5%) of 27 cases. CKMB mass values were within the normal range in 25 of the cases with MCK. Two patients with MCK-I were diagnosed as having AMI because of increased CKMB mass and positive electrocardiography findings. The incidence of MCK and/or high CKBB levels (0.82%) in the whole group was similar to that reported for a normal population. MCK existence and increased CKBB levels may cause misleading diagnoses if CKMB mass measurements and/or CKMB index values are not used together for patients with suspected AMI.
authors.affiliation: Department of Clinical Chemistry, Gülhane Military Medical Academy, Ankara, Turkey.
authors.forename: Muhittin A
authors.initials: MA
authors.lastname: Serdar
authors.forename: Serhat
authors.initials: S
authors.lastname: Tokgoz
authors.forename: Gürkan
authors.initials: G
authors.lastname: Metinyurt
authors.forename: Serkan
authors.initials: S
authors.lastname: Tapan
authors.forename: Kürşat
authors.initials: K
authors.lastname: Erinç
authors.forename: Adnan
authors.initials: A
authors.lastname: Haşimi
authors.forename: Levent
authors.initials: L
authors.lastname: Kenar
authors.forename: Cumhur
authors.initials: C
authors.lastname: BilgI
authors.forename: Türker
authors.initials: T
authors.lastname: Kutluay
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood*; D003402:Creatine Kinase / Q000097:blood*; D052276:Creatine Kinase, BB Form; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006772:Hospitals, Military; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000201:enzymology; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D003402:Creatine Kinase; D052276:Creatine Kinase, BB Form