D-dimer Biomarkers Research Articles

Efficacy of lipid, NT-proBNP and D-dimer biomarkers in the differential diagnosis of patients presenting to the emergency department with syncope

Aims: Syncope is defined as a temporary loss of consciousness in any disorder characterized by a self-limited loss of consciousness, whatever the mechanism. It constitutes 3% of emergency service applications. NT-proBNP, D-dimer and lipids are important parameters in the diagnosis and differential diagnosis of patients with syncope. This study aims to determine the levels of these biomarkers during and after treatment in patients admitted to the emergency department(ED) due to syncope. Methods: Forty-nine patients admitted to the emergency department due to syncope were included in this study. Forty-nine age- and sex-matched individuals without a history of syncope were taken as the control group. Blood samples were taken from the patient group three times, at the time of admission to the emergency department, 24 hours after admission, and on the day they were discharged from the hospital, and only once from the control group. The patient and control groups were compared in terms of NT-proBNP, D-dimer and lipids. Results: The mean HDL level at discharge was 33.63±9.62 mg/dl, which was significantly lower than the mean HDL level in the control group (38.77±10.33 mg/dl) (t=2.14, p=0.012). Although the mean LDL levels at discharge (108.02±48.03 mg/dl) were higher than the control group (92.53±37.39 mg/dl), this increase was not statistically significant (t=1.78, p=0.078). However, the mean LDL levels during hospitalization and after 24 hours (126.08±51.88 mg/dl, 116.26±48.21 mg/dl, respectively) compared to the control group (92.53±7.39 mg/dl) were statistically significantly higher (t=3.67, p=0.001, t=2.73, p=0.008). NT proBNP and D-dimer median values at the time of admission to the emergency department (844.00 pg/ml, 616.50 mcg/L, respectively), after 24 hours (1985.00 pg/ml, 662.00 mcg/L, respectively) and at discharge (748.00 pg/ml, 702.50 mcg/L respectively) compared to the control group (85.00 pg/ml, 176.00 mcg/L, respectively), a statistically significant increase was detected (p=0.001). Conclusion: In the patients admitted to the ED with a diagnosis of syncope, early treatment can be achieved getting the differential diagnosis of syncope in a short time with NT-proBNP, D-dimer and lipid blood levels that can be worked easily. In addition, the need for serious interventional procedures and further investigations in the diagnostic process will be reduced.

Detection of factor VIII and D-dimer biomarkers for venous thromboembolism diagnosis using electrochemistry immunosensor

Venous thromboembolism (VTE) is a serious clinical condition which early and accurate diagnosis may contribute to the reduction of associated morbidity and mortality. VTE occurs when a blood clot (thrombus) blocks the vein blood flow causing deep vein thrombosis (DVT) and, when it migrates to the lungs, it may clog the pulmonary arteries characterizing pulmonary embolism (PE). Analysis using fibrin degradation products or D-dimer and coagulation factor VIII may assist early diagnosis of VTE. Thus, two immunosensors were built using layer-by-layer (LbL) films technique, one containing the anti-D-dimer immobilized on polyethylene imine (PEI) and another the anti-FVIII on silk fibroin (SF). Immunosensor response, the antigen-antibody specific interaction, was investigated using cyclic voltammetry. When immunosensors, PEI/anti-D-dimer and SF/anti-FVIII, were exposed to antigens, D-dimer and Factor VIII, the voltammograms area and current were significantly increased with increasing specific antigen concentration. The specific interaction was confirmed with control experiments, electrodes containing only PEI or SF, that no significant changes in the voltammogram responses were observed and principal component analysis confirmed these results. The films formation and response were verified using scanning electronic microscopy (SEM). The developed immunosensor seems to be a promising and effective early complementary exam to assist in the VTE diagnosis, through the combined response of two biomarkers very sensible.

Low-Cost and Desktop-Fabricated Biosensor for Rapid and Sensitive Detection of Circulating D-Dimer Biomarker

Disposable point-of-care biomedical applications demand low-cost biosensing systems that can provide rapid detection with accessible fabrication requirements and user-friendly operation. Here, we present an easy-to-operate and cleanroom-free desktop-fabricated biosensor that is capable of reliable detection for human D-dimer biomarkers on-site. Interdigitated electrodes are used as the biosensor, and they are fabricated using commercial compact discs and home-made gadgets. The compact disc-based electrode arrays are patterned by wet-etching and followed by electroplating of polypyrrole (PPy). The nano-porous structures of PPy enhance the immobilization of protein probe on the electrode surface. The sensor performance is further enhanced by the ac electrokinetics (ACEK) capacitive sensing method. ACEK capacitive sensing induces ACEK effects that direct analytes toward the electrode surfaces, significantly promoting probe-target binding. Our sensor can quantitatively detect D-dimer biomarkers in 1 min with a limit of detection of 1 pg/mL. In contrast, Nyquist or Bode plots can only qualitatively distinguish positive and negative samples. Furthermore, the total cost of each test, together with the lithography material and compact disk, is only around U.S. $1, and it is acceptable to be disposable. The sensitive device yields wide-ranging and significant advantages for biomedical and lab-on-a-chip applications for undeveloped areas.