From the Guidelines
Your C-Reactive Protein (CRP) level of <5.0 mg/L is within the normal range and indicates a low likelihood of significant systemic inflammation. This result is based on the most recent evidence from 2023, which suggests that a CRP level of <5.0 mg/L is associated with low rates of false positives (FPs) in patients with Crohn's disease, as reported in the study published in Gastroenterology 1. The study found that elevated CRP (>5 mg/L) had low rates of being FP (4.0%) in high pretest probability scenarios, implying that a CRP level of <5.0 mg/L is a reliable indicator of the absence of significant inflammation. Some key points to consider include:
- The normal reference range for CRP is <8.0 mg/L, and your level is well within this range.
- CRP is an acute phase protein produced by the liver in response to inflammation, and elevated levels can indicate various conditions requiring medical attention.
- The study published in Gastroenterology 1 provides the most recent and highest quality evidence on the role of CRP in managing Crohn's disease, and its findings support the use of CRP levels to guide clinical decision-making.
- It is essential to interpret your CRP result in the context of your overall clinical presentation and other laboratory tests, as CRP is just one marker of inflammation. If you were experiencing symptoms that prompted this test, it would be appropriate to discuss these results with your healthcare provider to determine if additional evaluation is necessary. Regular monitoring of CRP may be recommended if you have chronic inflammatory conditions, even when levels are currently normal, as suggested by the study 1.
From the Research
C-Reactive Protein (CRP) Levels
- The given CRP level is <5.0 mg/L, which is within the reference range of <8.0 mg/L 2.
- CRP is an acute-phase reactant widely used clinically as a marker of inflammation, and it is synthesized by hepatocytes 2.
- Studies have shown that CRP levels can be lower in patients with chronic liver disease, and this can affect the reliability of CRP as a marker of inflammation in these patients 2.
Factors Affecting CRP Levels
- Liver disease can affect CRP levels, with patients having lower serum CRP levels during active disease episodes compared to those without liver disease 2.
- Infections, particularly bacterial infections, can cause highly elevated CRP levels, with a study showing that CRP values above 500 mg/L are highly related to bacterial infections 3.
- Other factors, such as immunocompromised conditions, can also affect CRP levels, with a study showing that 52% of patients with highly elevated CRP levels had an immunocompromised condition 3.
Clinical Use of CRP
- CRP is a useful inflammatory marker with rapid kinetics during the inflammatory process, but its levels can be affected by various factors, including liver disease and immunocompromised conditions 2, 3.
- A novel diagnostic algorithm has been proposed to carefully assess CRP levels for a precise diagnosis of medical conditions, taking into account various factors that can affect CRP levels 4.
- CRP has been identified as a separate risk factor for several cardiovascular diseases, and therapies aimed at lowering CRP levels may be beneficial for both primary and secondary cardiovascular disease prevention 5.
Relationship Between CRP and Other Conditions
- CRP has been linked to various diseases, including cardiovascular, respiratory, hepatobiliary, gastrointestinal, and autoimmune diseases, and its levels can be used as a biomarker for disease prognosis 4, 5.
- Non-steroidal anti-inflammatory drugs (NSAIDs) can affect CRP levels, and their use must be individualized based on the stratification of cardiovascular and gastrointestinal risk of patients 6.