From the Guidelines
The best inflammatory marker for clinical assessment is C-reactive protein (CRP), as it has the most conducive analyte and assay characteristics for use in practice, according to the most recent and highest quality study 1. When considering inflammatory markers, several options are available, including CRP, erythrocyte sedimentation rate (ESR), procalcitonin, and complete blood count with differential.
- CRP is particularly valuable as it rises rapidly within 4-6 hours of inflammation onset and has a half-life of 19 hours, making it responsive to changes in inflammatory status.
- ESR provides a complementary measure that rises more slowly but remains elevated longer, offering insight into more chronic inflammatory processes.
- Procalcitonin is especially useful for distinguishing bacterial infections from other causes of inflammation, with levels typically rising above 0.5 ng/mL in bacterial infections.
- Complete blood count with differential provides important information through white blood cell count and neutrophil-to-lymphocyte ratio. The most recent study 1 suggests that single measures of inflammatory biomarkers may be an adequate index of stable individual differences in the short term (<6 months), but repeated measures are recommended over intervals ≥6 months to 3 years, and are absolutely necessary over intervals >3 years to reliably identify stable individual differences in health risk. It's essential to establish baseline values for individual patients and to interpret results in clinical context rather than isolation, as these markers reflect the body's inflammatory response through different mechanisms - CRP is produced by the liver in response to IL-6, ESR measures red blood cell aggregation influenced by fibrinogen and immunoglobulins, and procalcitonin is released primarily in response to bacterial endotoxins 1.
From the Research
Inflammatory Markers
The following are some of the best inflammatory markers:
- C-reactive protein (CRP) 2, 3, 4, 5, 6
- Erythrocyte sedimentation rate (ESR) 4
- Procalcitonin (PCT) 5, 6
- Interleukin-6 (IL-6) 5, 6
- Interleukin-8 (IL-8) 5
- Interleukin-10 (IL-10) 5, 6
- Tumor necrosis factor-alpha (TNFα) 6
- Serum amyloid A 6
- Fibrinogen 6
- F2-isoprostanes 6
- Malondialdehyde 6
- 8-OH-dG 6
- Carbonylated proteins 6
Disease-Specific Markers
Some inflammatory markers are disease-specific, such as:
- CRP and PCT for gastrointestinal diseases 3
- CRP, PCT, and IL-6 for pediatric sepsis 5
- IL-8 and IL-10 for organ dysfunction in pediatric sepsis 5
Combination of Markers
Combining multiple inflammatory markers can improve diagnostic efficiency, such as: