Test Code CRP C-Reactive Protein
Specimen and Container/Tube
Specimen Type: Plasma
Preferred Specimen: Li-Heparin Mint Green Top
Other Acceptable specimens: Serum/Gold Top, Serum/Red Top
Volume
Preferred Volume: 0.5 mL
Minimum Volume: 0.2 mL
Specimen Stability
Storage Temperature |
Stability |
Room temperature |
2 weeks |
Refrigerated |
3 weeks |
Frozen |
12 months |
Collection Instructions
Collect specimen per standard laboratory collection procedures.
Specimen Handling and Transport Instructions
UCMC Onsite Instructions:
Collect specimen per standard collection procedure and send to laboratory immediately.
UCMC Offsite and UC MedLab Outreach Instructions:
- Samples should be centrifuged within 2 hours of collection.
- Centrifuge specimens at >2500 x g for 10 minutes at room temperature.
- Aliquot sample into plastic transport tube containing a minimum of 0.2 mL of specimen.
- Sample must be sent room temperature at 15-25oC
Rejection Criteria
- Common specimen rejected situations include: incorrect specimen type, insufficient volume, missing or incomplete specimen identifiers, incorrect specimen transport, or specimens outside stability limits.
- Specimens that are clotted or grossly hemolyzed.
- Specimens that where transported unspun/whole blood and draw time is greater than 6 ours.
Reference Values
Test |
Age |
Sex |
Reference Range |
CRP |
All |
All |
<5 mg/L |
Note: Reference range based on in-house studies, on the recommendations from Tietz Textbook of Clinical Chemistry and Roche Diagnostics product literature.
Critical Values
Not applicable
Turnaround Time
Turnaround times are relative to the time the specimen is received in the test laboratory.
STAT Turnaround Time: 1 hour
Routine Turnaround Time: 4 hours
Testing Schedule: 24/7
Clinical Indications
CRP assays are used to detect systemic inflammatory processes; to assess treatment of bacterial infections with antibiotics; to detect intrauterine infections with concomitant premature amniorrhexis; to differentiate between active and inactive forms of disease with concurrent infection; to determine the presence of post-operative complications at an early stage, such as infected wounds.
Test Components
C-Reactive Protein
Methodology
Particle Enhanced Immunoturbidimetric Assay (Roche Diagnostics)
CPT Codes
86140
LOINC Codes
1988-5
Synonyms/Keyword Search
Protein, C-Reactive, CRP, C Reactive, CRPQ
Additional Information
- Results should always be assessed in conjunction with patient's medical history, clinical examination and other findings.
- High dose hook-effect: No false result occurs up to a CRP concentration of 1200 mg/L.
- Ticarcillin causes no significant interference up to 225 mg/L.
- CRP response may be less pronounced in patients suffereing from liver disease.
- Postoperative monitoring of CRP level of patients can aid in the recognition of unexpected complications (persisting high or increasing levels. Measuring changes in the concentration of CRP provides useful diagnostic information about how acute and how serious a disease is. It also allows judgements about the disase genesis. Persistence of high serum CRP concentrations is usually a grave prognostic sign which generally indicates the presence of an uncontrolled infection.
Last Review Date
5/6/2025