Clinical chemistry
-
Hemostasis is initiated by injury to the vascular wall, leading to the deposition of platelets adhering to components of the subendothelium. Platelet adhesion requires the presence of von Willebrand factor and platelet receptors (IIb/IIIa and Ib/IX). ⋯ In this review, I consider laboratory tests used to evaluate coagulation, including prothrombin time, activated partial thromboplastin time, thrombin time, and platelet count. I discuss hereditary disorders of platelets and/or coagulation proteins that lead to clinical bleeding as well as acquired disorders, including disseminated intravascular coagulation and acquired circulating anticoagulants.
-
Cardiac depression in severe sepsis and septic shock is characterized by left ventricular (LV) failure. To date, it is unclear whether clinically unrecognized myocardial cell injury accompanies, causes, or results from this decreased cardiac performance. We therefore studied the relationship between cardiac troponin I (cTnI) and T (cTnT) and LV dysfunction in early septic shock. ⋯ These findings suggest that in septic shock, clinically unrecognized myocardial cell injury is a marker of LV dysfunction. The latter condition tends to occur more often in severely ill older patients with underlying cardiovascular disease. Further studies are needed to determine the extent to which myocardial damage is a cause or a consequence of LV dysfunction.
-
Multicenter Study Comparative Study Clinical Trial
Clinical efficacy of three assays for cardiac troponin I for risk stratification in acute coronary syndromes: a Thrombolysis In Myocardial Infarction (TIMI) 11B Substudy.
Significant analytic variability exists between the multiple assays for cardiac troponin I (cTnI) approved for clinical use. Until adequate cTnI standardization is possible, an evidence-based approach evaluating each assay at specific thresholds appears warranted. ⋯ This study demonstrates the prognostic efficacy of three independently developed cTnI assays at a threshold of 0.1 microg/L for the prediction of adverse clinical outcomes among patients with non-ST-elevation acute coronary syndromes.
-
Case Reports
Propofol-associated rhabdomyolysis with cardiac involvement in adults: chemical and anatomic findings.
Propofol, a central-acting sedative agent, has been implicated in the development of rhabdomyolysis in children. We describe two adults who developed rhabdomyolysis after receiving high rates of propofol infusion. ⋯ Creatine kinase and cardiac troponin I values were highly correlated in each patent (r = 0.786 and 0.988 in patients one and two, respectively). Autopsy of one patient confirmed the diagnosis of skeletal and cardiac rhabdomyolysis.
-
Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) have been suggested to have protective effects against cardiovascular disease, cancer, immune-modulated diseases, and aging. We examined serum concentrations of DHEA, DHEA-S, and pregnenolone sulfate (PREG-S) in patients with thyroid dysfunction. ⋯ Serum concentrations of DHEA, DHEA-S, and PREG-S were decreased in hypothyroidism, whereas serum DHEA-S and PREG-S concentrations were increased but DHEA was normal in hyperthyroidism. Thyroid hormone may stimulate the synthesis of these steroids, and DHEA sulfotransferase might be increased in hyperthyroidism.