[The significance of a 4,183 Da peptide of dermcidin protein in the early diagnosis and differential diagnosis of acute coronary syndrome].

OBJECTIVE

To investigate the predictive value of 4,183 Da peptide of dermcidin protein in the early diagnosis and differential diagnosis of ischemic heart disease.

METHODS

A prospective controlled study was conducted. Serum samples were drawn from 161 patients with acute coronary'syndrome [ACS, including 46 patients with unstable angina (UA), 23 with acute non-ST elevation myocardial infarction, and 92 with acute ST segment elevation myocardial infarction], 111 subjects for routine physical examination, including 45 patients with hypertension history, 42 with coronary heart disease, 22 with diabetes, and 54 patients with non-ACS (including pulmonary embolism, aortic dissection, aneurysm, arrhythmia, myocarditis, coronary myocardial bridge, pleurisy, pneumothorax pneumomediastinum, rib fracture, reflux esophagitis, peptic ulcer, and pancreatitis) to serve as controls. 4 183 Da peptide of dermcidin protein was assessed with matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) technology, and myeloperoxidase [MPO, determined by point-of-care testing (POCT) and enzyme linked immunosorbent assay (ELISA), respectively], high sensitive C-reactive protein (hs-CRP), heart type fatty acid binding protein (H-FABP), myoglobin (MYO), cardiac troponin I (cTnI), and MB isoenzyme of creatine kinase (CK-MB) were quantitated with biochemical analysis. The power of the biomarkers above for early diagnosis and differential diagnosis for ischemic heart disease were judged by comparison of their sensitivity and specificity.

RESULTS

(1) It was showed by one-way ANOVA that 4,183 Da peptide was higher in ACS group than that in control group (relative abundance: 22.05 ± 16.97 vs. 15.52 ± 14.09, P = 0.001), but no difference was found between ACS group and non-ACS group (relative abundance: 22.05 ± 16.97 vs. 19.99 ± 17.63, P = 0.416). (2) The specificity and sensitivity of the 4 183 Da polypeptide and MPO for predicting ACS and UA were compared with the receiver operating characteristic curve (ROC). It was showed that the 4,183 Da polypeptide had predictive values for ACS and UA, and the areas under the ROC curve (AUC) was 0.625 and 0.651 (both P < 0.01), but MPO was not found to have predictive value (AUC was 0.440 and 0.336, respectively, both P > 0.05). (3) It was showed by the values of multi-markers in differential diagnosis of ACS and non-ACS disease that the specificity and sensitivity of 4 183 Da peptide in the differential diagnosis of acute myocardial infarction (AMI) and non-ACS disease were less than those of MYO, cTnI, H-FABP, markers of myocardial damage, which AUCs were 0.569 vs. 0.796, 0.833, 0.838, and equal to MPO (POCT/ELISA) and hs-CRP, AUC of which was 0.569 vs. 0.505 (POCT)/0.477 (ELISA) and 0.545. But both the value of 4 183 Da peptide and MYO, cTnI, H-FABP in the differential diagnosis of UA and non-ACS disease was not found, where AUC was 0.456, 0.525, 0.658, 0.568.

CONCLUSION

4,183 Da polypeptide, a fragment of dermcidin protein, may have association with the onset of ischemic heart disease, and may be helpful in the early diagnosis of ACS.