From the Guidelines
Elevated C-reactive protein (CRP) levels are primarily caused by inflammation in the body, which can be triggered by infections, inflammatory conditions, tissue damage, chronic diseases, and certain medications, as supported by recent studies 1, 2, 3.
Causes of Elevated CRP
The most common causes of elevated CRP include:
- Infections (bacterial, viral, or fungal)
- Inflammatory conditions like rheumatoid arthritis, lupus, or inflammatory bowel disease
- Tissue damage from injuries, surgeries, or heart attacks
- Chronic conditions such as obesity, diabetes, smoking, and cardiovascular disease
- Certain medications like hormone replacement therapy or birth control pills ### Mechanism of CRP Elevation The elevation of CRP occurs because the liver produces more CRP when inflammatory cytokines are released during these conditions. CRP levels typically rise within hours of an inflammatory trigger and can increase hundreds of times above normal.
Normal CRP Levels and Inflammation
Normal CRP levels are generally below 10 mg/L, with levels above this suggesting significant inflammation.
Treatment and Monitoring
Treatment focuses on addressing the underlying cause rather than the CRP itself, which serves primarily as a marker rather than a disease. Regular monitoring of CRP can help track inflammatory disease activity and response to treatment, as noted in a study published in the World Journal of Emergency Surgery 3.
Clinical Considerations
It is essential to consider the clinical context when interpreting CRP levels, as elevated levels can have various causes, and a thorough evaluation is necessary to determine the underlying cause, as discussed in a study published in Brain, Behavior, and Immunity 2.
Recent Findings
A recent study published in Sports Medicine 1 highlights the importance of considering the impact of exercise on CRP levels, as short-term increases can occur after intense physical activity.
From the Research
Causes of Elevated C-Reactive Protein
- Infection: C-reactive protein (CRP) is an acute inflammatory protein that increases up to 1,000-fold at sites of infection or inflammation 4, 5, 6.
- Inflammation: CRP is involved in host defense and inflammation, and its levels can increase in response to tissue injury or inflammation 4, 5, 6.
- Tissue injury: CRP levels can increase in response to tissue injury, and the magnitude of CRP increase usually correlates with the severity of injury or inflammation 5, 6.
- Autoimmune disease: CRP may play a role in autoimmune disease, and its levels can be elevated in patients with autoimmune diseases such as systemic lupus erythematosus 7, 8.
- Cardiovascular disease: CRP is a known marker of cardiovascular disease, and its levels can be elevated in patients with cardiovascular disease 4, 6.
Factors that Influence CRP Levels
- Estrogen: Estrogen in the form of hormone replacement therapy can influence CRP levels in the elderly 4.
- Liver function: CRP is synthesized primarily in liver hepatocytes, and liver function can affect CRP levels 4.
- Adipocytes: CRP is also synthesized by adipocytes, and adipose tissue can affect CRP levels 4.
Clinical Significance of Elevated CRP
- Elevated CRP levels can indicate infection, inflammation, or tissue injury 4, 5, 6.
- Elevated CRP levels can also indicate an increased risk of cardiovascular disease 4, 6.
- However, the clinical significance of elevated CRP levels can be limited by the lack of specificity and sensitivity of CRP as a diagnostic marker 8.