C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are indicators of inflammation. They are known as acute phase proteins, which reflect a measure of the acute-phase response. The term "acute phase" refers to local and systemic events that accompany inflammation. The clinical use of acute phase proteins is as an aid to diagnosis, not a confirmation of or dismissal of a diagnosis. Because the acute phase response is relatively non-specific, the value of measuring acute-phase protein concentrations is to assess the extent of inflammation reflecting momentary disease activity. Similar to tumor markers, acute-phase proteins may monitor the course of disease in response to therapeutic intervention (drug treatment regimen).
Therefore, you can still have the disease with symptoms, but markers of acute inflammation are normal which only reflects the ACTIVITY of certains aspects of the disease at that particular time..not weather or not you have the disease.
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