title: Creatine kinase-MB: the journey to obsolescence.
abstract: OBJECTIVE
  To evaluate the clinical utility of and demand for the creatine kinase (CK)-MB assay.
  
  
  METHODS
  We examined the number of CK-MB tests from 2007 through 2013 while we progressively deemphasized their use. We first removed CK-MB from the acute coronary syndrome (ACS) panel and then from the main menu and observed the demand for the test. We also reviewed patient medical records to assess the appropriateness of its use.
  
  
  RESULTS
  After removing CK-MB from the ACS panel, the test volume dropped from around 12,000 per year to about 150 per year. In reviewing the records of 171 patients who had CK-MB determination done over a 28-month period, we discovered that CK-MB contributed to the diagnosis in only one patient, although it was not essential. Since removing CK-MB from the laboratory menu, two CK-MB tests were ordered in 4 months, and neither added value.
  
  
  CONCLUSIONS
  CK-MB determinations do not add value to information available from the troponin assay and can be safely removed from the laboratory menu.
authors: Truman Medical Center, 2310 Holmes St, Kansas City, MO 64108; e-mail: gurmukhsinghmdphd@yahoo.com.
authors: Gurmukh
authors: G
authors: Singh
authors: Paramdeep S
authors: PS
authors: Baweja
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis*; D052279:Creatine Kinase, MB Form / Q000032:analysis*; D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data*; D006801:Humans; D007755:Laboratories, Hospital; D009203:Myocardial Infarction / Q000175:diagnosis*
chemical_list: D052279:Creatine Kinase, MB Form
keywords: Acute coronary syndrome; CK-MB; Obsolete laboratory tests; Troponin