C reactive protein

ChemistryAlso known as: C-reactive proteinAlso known as: CRPmg/L

Measures C-reactive protein inflammation marker in serum or plasma.

Normal Range
3 mg/L
mg/L
Abnormal Levels
< 0 mg/L
> 3 mg/L
Specimen Type
Blood

Why This Biomarker Matters

Elevated CSF CRP indicates serious brain or spinal cord infection or inflammation, requiring prompt diagnosis and treatment to prevent complications.

Understanding Your Results

Normal Range

3 mg/L

Optimal Ranges

Clinician-defined 4-point reference thresholds (mg/L)

Default Range

0
0
1
3
Low
0 mg/L
Borderline Low
0 mg/L
Optimal
1 mg/L
Borderline High
3 mg/L

Overview

C-reactive protein (CRP) is an acute-phase protein produced by the liver in response to inflammation. Measured in serum or plasma, CRP is one of the most widely used markers of systemic inflammation. It rises rapidly (within hours) in response to bacterial infections, autoimmune flares, tissue injury, and malignancy. High-sensitivity CRP (hs-CRP) at lower levels is used for cardiovascular risk stratification. CRP is valuable for monitoring treatment response in rheumatologic conditions, infections, and post-surgical recovery. Unlike ESR, CRP responds quickly to changes in inflammatory status.

Technical Information (LOINC Codes)

Standardized laboratory codes for this biomarker

1988-5Primary
C reactive protein [Mass/volume] in Serum or Plasma
mg/L
30522-7
C reactive protein [Mass/volume] in Serum or Plasma by High sensitivity method
mg/L
11039-5
C reactive protein [Presence] in Serum or Plasma
45062-7
C reactive protein [Mass/volume] in Cerebral spinal fluid
mg/L
35648-5
C reactive protein [Quintile] in Serum or Plasma by High sensitivity method
71426-1
C reactive protein [Mass/volume] in Blood by High sensitivity method
mg/L
16503-5
C reactive protein [Mass/volume] in Body fluid
mg/dL
14634-0
C reactive protein [Titer] in Serum or Plasma
{titer}
98987-1
C reactive protein [Units/volume] in Body fluid
[arb'U]/L
106736-2
C reactive protein [Mass/volume] in Serum, Plasma or Blood by Rapid immunoassay
mg/L;ug/mL;mg/dL
48421-2
C reactive protein [Mass/volume] in Capillary blood
mg/L
59182-6
C reactive protein [Mass/volume] in Cerebral spinal fluid by High sensitivity method
mg/L
76485-2
C reactive protein [Moles/volume] in Serum or Plasma
nmol/L
76486-0
C reactive protein [Moles/volume] in Serum or Plasma by High sensitivity method
nmol/L
105126-7
C reactive protein [Mass/volume] in Serum, Plasma or Blood
mg/dL