April 1, 2024 Author : Sara Lemos Rocha What is C-reactive protein? C-reactive protein is a protein produced in the liver and that can be dosed in the blood. It belongs to a group called acute-phase proteins, which are related to the reactione to acute or chronic inflammation. Inflammation can have many infectious or non-infectious causes, such as trauma, some types of cancer, autoimmune diseases, among others. C-reactive protein dosing is a blood test that can indicate whether inflammation or acute infection occurs. It is not a specific test as it does not identify the cause of the inflammation / infection. When and how is C-reactive protein test performed? The determination of C-reactive protein can be requested by the doctor for different purposes, for example: Help a diagnosis when acute or chronic inflammation is suspected; Monitor the evolution of inflammation and the response to treatment; Stratify cardiovascular risk, although in this area the use of C-reactive protein is still controversial. The determination of C-reactive protein is carried out in a blood sample and, therefore, is part of the group of diagnostic tests currently known as blood tests. It does not require prior fasting, but it is common to be done along with other blood tests, some of which require fasting. The results Levels of C-reactive protein in the blood increase when there is inflammation, but there may also be a slight increase in other situations, even without signs of inflammation. Reference values for C-reactive protein vary greatly depending on the laboratory, but in general, in most healthy adults, C-reactive protein has a value below 0.3 mg/dL. It is known that normal values increase with age and are slightly higher in women. Values between 0.3-1.0 mg/dL are considered slight increases and can be observed in different situations, many without signs of inflammation, for example obesity, labor, diabetes, insomnia, depression, physical inactivity, smoking, unhealthy diet, among others. Values between 1.0-10.0 mg/dL are considered moderate increases. Values greater than 10.0 mg/dL are considered marked increases. In infections caused by bacteria, the increase in C-reactive protein is, as a rule, greater than in infections caused by viruses. Several medications, including some over-the-counter medications, can distort the results of a C-reactive protein test. An isolated increase in C-reactive protein may be meaningless. C-reactive protein values must be analyzed with the results of other diagnostic tests and of medical evaluation, mainly when dealing with mild to moderate increases. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
