Assessment of the nickel-albumin binding assay for diagnosis of acute coronary syndrome.

BACKGROUND: Myocardial ischemia may alter the metal binding capacity of circulating serum albumin. Thus, the aim of this study was to describe an automated method to measure ischemia-induced alterations in the binding capacity of serum albumin for exogenous nickel, and to evaluate the diagnostic characteristics of this assay for the assessment of acute coronary syndrome (ACS) in patients presenting to the emergency room (ER) with acute chest pain. METHODS: We assessed the concentrations of cardiac troponin I (cTnI), serum albumin, ischemia-modified albumin (IMA) measured by the cobalt-albumin binding assay (CABA), and by an automated nickel-albumin binding assay (NABA) in the following groups: ACS (n=63) and non-ischemic chest pain (NICP, n=26). Biochemical markers were determined in blood samples obtained from patients within 3 h of ER admission. RESULTS: cTnI, CABA and NABA concentrations were higher in ACS group in comparison to the NICP group. A significant correlation between NABA and CABA was observed (r=0.5387, p<0.001). Areas under the curve for CABA and NABA were 0.7289 and 0.7582, respectively. Both CABA and NABA have the ability to discriminate patients with ACS. However, NABA has a slightly higher ability to discriminate ACS compared with CABA. CONCLUSIONS: Patients with ACS have reduced nickel binding to human serum albumin, and NABA may have an important role as an early marker of myocardial ischemia, particularly in patients presenting to the ER with acute chest pain.

Characteristics of a nickel-albumin binding assay for assessment of myocardial ischaemia.

BACKGROUND: The aim of this study was to describe a method to measure ischaemia-induced alterations of the binding capacity of serum albumin to exogenous nickel. METHODS: We measured the levels of cardiac troponin I (cTnI), serum albumin, ischaemia-modified albumin (IMA) measured by a cobalt-albumin binding assay (CABA), and a nickel-albumin binding assay (NABA) in the following groups: myocardial infarction (n = 32) and non-ischaemic chest pain (n = 64). RESULTS: IMA, cTnI and NABA levels were higher in the myocardial infarction group. NABA presented a higher ability to discriminate myocardial ischaemia than CABA. CONCLUSIONS: Patients with myocardial infarction have reduced nickel binding to human serum albumin, and NABA may have an important role as an early marker of myocardial ischaemia.

Evaluation of ischemia-modified albumin in myocardial infarction and prostatic diseases.

BACKGROUND: Ischemia-modified albumin (IMA) has been shown to be a rapidly rising and sensitive biochemical marker for the diagnosis of myocardial ischemia. In this study, we evaluated the levels of IMA in myocardial infarction and prostate diseases, as well as the influence of HDL cholesterol levels on C-reactive protein (CRP) and IMA levels. METHODS: A total of 27 patients with myocardial infarction (MI), 102 patients with benign prostatic hyperplasia (BPH), 84 patients with prostate cancer (PCA), and 21 healthy subjects were enrolled in this study. IMA levels were measured in whole studied patients. Cardiac troponin I (cTnI), cholesterol, HDL cholesterol, and CRP were measured in MI and control groups. RESULTS: IMA values were significantly higher in patients with MI (0.5215+/-0.0241 ABSU) and BPH (0.4150+/-0.0156 ABSU) in comparison to control subjects (0.3381+/-0.0194 ABSU). IMA and CRP were higher in MI group, especially in patients with HDL cholesterol levels lower than 38 mg/dL. The ability of IMA to discriminate myocardial infarction was higher than CRP. Significant correlations between CRP and HDL, CRP and IMA, and HDL and IMA were reported. CONCLUSIONS: IMA and CRP increase in myocardial damage, and the decrease of HDL cholesterol appears to enhance the inflammatory response. IMA also increase in benign prostate hyperplasia and this finding suggests that the diagnosis of prostate diseases must be considered on evaluation of IMA as a marker of cardiac ischemia.