Introduction to Biomarkers
- Biomarkers are measurable indicators of biological states.
- They are used for disease diagnosis, prognosis, and monitoring.
- Biomarkers can be proteins, genes, enzymes, or structural changes.
- They can be classified as markers of exposure or markers of disease.
Characteristics of an Ideal Biomarker
|High sensitivity with organ specificity
|Accurate detection of organ-related changes.
|Immediate release with tissue injury
|Rapid response to tissue damage.
|Release proportional to insult
|The extent of release correlates with the injury.
|Long half-life for predictiveness
|Sustained presence for predictive purposes.
|Rapid decrease in concentration for monitoring
|Quick clearance for monitoring.
|Rapid, simple, accurate, and inexpensive measurement
|Easy and cost-effective assessment.
|Noninvasive and accessible
|Easily obtainable without invasive procedures.
Biomarkers of the Cardiovascular System
|C-reactive Protein (CRP)
|Marker of inflammation, linked to heart disease
|Risk assessment for coronary artery disease, rheumatoid arthritis, and lupus.
|Indicators of heart muscle damage
|Diagnosis of myocardial infarction and risk assessment in patients with end-stage renal disease.
|B-type Natriuretic Peptide (BNP)
|Reflects heart failure
|Diagnosis and prognosis in congestive heart failure.
|Soluble Urokinase Plasminogen Activation Receptor (suPAR)
|Risk prediction for cardiovascular disease.
Biomarkers of Kidney Injury
|Neutrophil gelatinase-associated lipocalin (NGAL)
|Reflects kidney injury
|Early diagnosis and risk prediction of acute kidney injury.
|Enzyme found in kidney tubules
|Prediction of renal replacement therapy in AKI patients.
|Urinary cystatin C and Plasma cystatin C
|Reflect kidney function
|Diagnosis and prediction of AKI and assessment of glomerular filtration rate.
|Kidney injury molecule-1 (KIM-1)
|Marker of kidney injury
|Prediction of AKI and adverse outcomes.
|Interleukin 18 (IL-18)
|Predicts death or AKI.
Biomarkers of Gut Failure
|Marker of enterocyte mass
|Indicator of enterocyte damage and bacterial translocation.
|Fatty Acid-binding Protein (I-FABP)
|Reflects intestinal epithelium damage
|Early detection of intestinal injury.
|Differentiates bacterial from viral infections and guides antibiotic use.
|RNA molecules reflecting cellular changes
|Potential for diagnosing various disorders and sepsis.
Biomarkers of Brain Damage and POCD
|Found in astroglial Schwann cells
|Used in detecting brain damage in surgery and trauma.
|Reflects blood-brain barrier dysfunction
|Associated with postoperative cognitive dysfunction (POCD).
|Α-II Spectrin Breakdown Product (SBDP) 145,150,120
|Reflects neuronal injury
|Potential marker for traumatic brain injury.
- Biomarkers play a crucial role in diagnosing and monitoring various medical conditions.
- While promising, their accuracy and clinical relevance may vary.
- More research is needed to validate the use of newer biomarkers in clinical practice.