Test Code LAB10458 Procalcitonin
Specimen Requirement
Lithium Heparin Plasma or Serum
PST Tubes and SST Tubes acceptable – remove from gel immediately after centrifugation
Do not add to specimen stored in a PST or SST gel tube
Specimen Stability
24 hours at 20-25° C
2 days at 2-8° C
15 days at -20° C
Testing Schedule
Daily
Reference Range
< 0.07 ng/mL
Interpretation
Procalcitonin should always be interpreted in the clinical context of the patient; results should be considered in conjunction with other laboratory findings and clinical signs of the patient.
Respiratory Tract Infection – Outpatient
- PCT: ≤ 0.25 ng/mL – Starting antibiotics not recommended
- PCT: >0.25 ng/mL – Start antibiotics; complete course as directed. Outpatient follow up as appropriate
Respiratory Tract Infection – Inpatient
- PCT: ≤0.25 ng/mL – Starting antibiotics not recommended; recheck PCT after 6-24 hours
- Consider stopping antibiotics if started
- PCT: >0.25 ng/mL – Start empiric antibiotics; repeat PCT every 2-3 days
- Consider stopping antibiotics when PCT ≤ 0.25 ng/mL or decreases >80% from peak if initial PCT >0.5 ng/mL
Sepsis
- PCT Baseline: Empiric antibiotics recommended in all patients with clinical suspicion of infection; check PCT daily
- PCT: ≤ 0.5 ng/mL or a decrease >80% from peak – Consider stopping antibiotics if patient is clinically stable
Note: Baseline PCT values may be elevated in CKD (CrCl <30 ml/min); please see full protocol on AltruLink (Physicians => Forms & Tools => Antimicrobial Stewardship) for recommendations.
Testing Department
Chemistry
Method
Chemiluminescent Microparticle Immunoassay (CMIA)
CPT Code
84145