Table 2.
Biomarkers of burn-induced pathophysiological conditions and complications
| Biomarker | Function | Levels post-burn | Clinical implications or signified outcomes |
|---|---|---|---|
| Endotheliopathy | |||
| Syndecan-1 | Major component of the endothelial glycocalyx (33) | Increased (33,56,59) | Poor patient outcomes including mortality (33,56,59) |
| sTM | Cleaved form of thrombomodulin (59) | Increased (59) | Independent predictor of 7-day and 28-day mortality (60) |
| TFPI | Coagulation inhibitor (56) | Increased (56) | Greater mortality risk; independent predictor of 30-day in-hospital mortality (56) |
| Ang-2:Ang-1 | Growth factors and Tie-2 receptor antagonist (Ang-2) and agonist (Ang-1) (61) | Increased (61,62) | Higher ratio found amongst those with greater disease burden as well as in non-survivors (62) |
| IL-6, TNF-⍺ | Also biomarkers of burn-induced immunopathy, refer to Table 1 | ||
| Coagulopathy | |||
| VIIa | Activated form of factor VII (80) | Increased (80) | Higher levels present in non-survivors (80) |
| VIIc | Procoagulant factor (80) | Low (80) | Lower post-burn day 1 levels in survivors (80) |
| TAT Complex | Marker of thrombin generation and neutralization (65) | Increased (65,66,80,81) | Day 7 TAT levels are prognostic indicator for ICU mortality (65,81) |
| F1.2 | Marker of thrombin generation (65) | Increased (65,81) | Reflects increased thrombin generation (65) |
| Antithrombin | Natural anticoagulant (65,80,81) | Decreased (65,80,81) | Decreased antithrombin represents greater thrombogenicity (65); low antithrombin levels predicts mortality and length of hospital stay (64,82) |
| PC | Natural anticoagulant (65,80,81) | Decreased (65,80,81) | Days 5 and 7 PC levels serve as independent predictors of ICU mortality (81) |
| PS | Natural anticoagulant (65,81) | Decreased (65,81) | Day 3, 5, and 7 PS levels are independent predictors of ICU mortality (81) |
| t-PA | Factor of the fibrinolytic system (65) | Increased (64–66,80,81) | Associated with disseminated intravascular coagulopathy (80) |
| PAI-1 | Factor of the fibrinolytic system; inhibits t-PA (65,80) | Increased (65,66,80,81) | PAI-1 counterbalances effects of t-PA (65); day 3 PAI-1 levels offer prognostic value for ICU mortality (65) |
| D-dimer | Fibrin degradation product (65) | Increased (65,80,81) | Indicates greater thrombin generation, fibrin formation and degradation (65) |
| Hepatic Dysfunction | |||
| ALT and AST | Liver enzymes (85–87,89) | Increased (85–87,89) | Indicators of hepatocyte damage; correlated with extent of liver injury (85–87,89) |
| ALKP | Serum enzyme related to liver function (7) | Increased (43,85,86) | Elevated levels indicate extent of liver injury (43,85,86) |
| AAPR | Ratio of albumin to alkaline phosphatase (89) | Decreased (89) | Higher ratios associated with increased chance of ICU discharge (89) |
| GLDH | Mitochondrial enzyme found in the liver (43) | Increased (7,90,91) | Elevated levels indicate extent of liver injury (7,90,91) |
| TBIL | Waste product processed by liver (88) | Increased (88) | Indicative of liver dysfunction; associated with increased mortality (88) |
| GSH | Protects hepatocytes from oxidative stress (92) | Decreased (92) | Increased oxidative stress and hepatocyte damage (92) |
| Renal Failure | |||
| sCR | Waste product filtered by kidneys (100) | Increased (100) | Indication of kidney damage and decreased renal function (100) |
| Cystatin C | Involved in kidney filtration (100) | Increased (100) | Poor kidney function (100) |
| NGAL | Associated with kidney injury (100) | Increased (100) | Risk of renal complications and mortality (100) |
| KIM-1 | Transmembrane protein (101) | Increased (101) | Associated with early indication of kidney injury (101) |
| Cardiac Dysfunction | |||
| CK-MB Isoenzyme | Isoenzyme specific to cardiac muscle (102,107) | Increased (102,107) | Indication of heart damage (102,107) |
| cTnI | Regulatory protein specific to cardiac muscle (95,100,101) | Increased (95,100,101) | Elevated concentrations are found only in presence of cardiac injury (95,100,101) |
| Sepsis | |||
| CRP | Acute inflammatory protein (131) | Increase (2,113,114) | Predictor of infection; can indicate sepsis before appearance of clinical symptoms (113,114) |
| PCT | Precursor of the calcitonin hormone (2,116) | Increased (116–118) | Lower levels found in surviving septic patients (111,118,119,121) |
| IL-6, IL-8, IL-10, IFN-ɣ, TNF-⍺ | Also biomarkers of burn-induced immunopathy, refer to Table 1 | ||
sTM: Soluble thrombomodulin; TFPI: Tissue factor pathway inhibitor; Ang: Angiopoietin; VIIa: Activated factor VII; VIIc: Procoagulant factor VII; TAT: Thrombin-antithrombin; F1.2: Prothrombin fragment; PC: Protein C; PS: Protein S; t-PA: Tissue plasminogen activator; PAI-1: Plasminogen activator inhibitor 1; ALT: Alanine transferase; AST: Aspartate aminotransferase; ALKP: Alkaline phosphatase; AAPR: Albumin-to-alkaline phosphatase ratio; GLDH: Glutamate dehydrogenase; TBIL: Total bilirubin; GSH: Glutathione; sCR: Serum creatinine; NGAL: Neutrophil elatinase associated lipocalin; KIM-1: Kidney injury molecule-1; CK-MB: Creatine kinase-MB; cTnI: Cardiac troponin I; CRP: C-reactive protein; PCT: Procalcitonin