C-Reactive Protein (CRP)

A general marker of inflammation or infection.

What it is

C-Reactive Protein, or CRP, is a protein produced by your liver. It's a substance that your body makes in response to inflammation or infection. Think of it as one of your body's alarm signals. When there's a problem, like an injury, an infection, or a chronic inflammatory condition, your liver releases more CRP into your bloodstream. The amount of CRP in your blood can give doctors an idea of how much inflammation or infection might be present.

The normal level of CRP in a healthy person is usually quite low, typically less than 5 mg/l (milligrams per litre). If your CRP level is higher than this, it suggests that your body is reacting to something.

Why it matters

Measuring your CRP level can be a useful tool for your doctor. It helps them to:

• Detect inflammation or infection: A high CRP level can indicate that something is wrong, even before you might have obvious symptoms.
• Assess the severity of a condition: A very high CRP level might suggest a more significant infection or inflammatory process.
• Monitor treatment effectiveness: If you're being treated for an infection or an inflammatory condition, your doctor might check your CRP levels to see if the treatment is working. If the CRP level starts to come down, it can be a good sign that the treatment is helping to control the inflammation or infection.
• Identify potential complications: In some situations, a rising CRP level could signal that a condition is worsening or that a complication has developed.

It's important to remember that CRP is a general marker. It tells us there's inflammation or infection, but it doesn't tell us what is causing it. Further tests are usually needed to pinpoint the exact cause.

What can cause it to be high or low

High CRP levels can be associated with:

• Infections: This is one of the most common reasons for a raised CRP. Bacterial infections, viral infections, and fungal infections can all lead to increased CRP. For example, pneumonia, urinary tract infections, or skin infections.
• Inflammatory conditions: Many conditions that cause inflammation in the body can raise CRP levels. This includes autoimmune diseases like rheumatoid arthritis or lupus, inflammatory bowel disease (Crohn's disease or ulcerative colitis), and conditions like gout.
• Tissue injury: Following surgery, a heart attack, or significant physical trauma, CRP levels can rise as the body responds to the damaged tissue.
• Certain cancers: Some types of cancer can also be associated with elevated CRP levels.
• Obesity: People who are overweight or obese may have slightly higher baseline CRP levels, as fat tissue can produce inflammatory substances.

Low CRP levels are generally a good sign, indicating a lack of significant inflammation or infection. However, it's worth noting that in some very specific or early-stage conditions, CRP might not be significantly elevated, or in certain severe illnesses, the liver's ability to produce CRP might be impaired, leading to lower-than-expected levels.

Lifestyle factors that may help

While CRP is a marker of acute issues, some lifestyle choices can help manage underlying inflammation that might contribute to higher CRP levels over time. Discussing these with your GP is a good idea:

• Healthy Diet: Focusing on a diet rich in fruits, vegetables, whole grains, and lean proteins, and lower in processed foods, saturated fats, and sugar, is often recommended for overall health and can help reduce inflammation.
• Regular Exercise: Engaging in regular physical activity can have anti-inflammatory effects. Finding an activity you enjoy, whether it's walking, swimming, or cycling, can be beneficial.
• Weight Management: If you are overweight, achieving and maintaining a healthy weight can help reduce inflammation throughout the body.
• Stress Management: Chronic stress can contribute to inflammation. Exploring techniques like mindfulness, meditation, or yoga might be helpful.
• Adequate Sleep: Ensuring you get enough quality sleep is crucial for your body's repair processes and can influence inflammatory markers.
• Avoiding Smoking: Smoking is a significant contributor to inflammation and various diseases. Quitting smoking can have profound positive effects on your health.

Questions to discuss with your GP

If your CRP level has been measured, or if you're concerned about inflammation or infection, here are some questions you might want to discuss with your GP:

• What does my specific CRP result mean in the context of my overall health?
• Could my CRP level be related to any of my current symptoms or medical conditions?
• Are there any further tests you would recommend to investigate the cause of a high CRP level?
• What are the potential long-term implications of having elevated CRP levels?
• Are there any specific lifestyle changes you would advise for me to help manage inflammation?
• How often should my CRP levels be monitored, if at all?