Procalcitonin, blood

Lab area

Clinical Biochemistry - General

Method and equipment

Equipment : Roche Cobas Pro e801

Method : Sandwich principle. Total duration of assay: 18 minutes.
▪ 1st incubation: Antigen in the sample (18 µL), a biotinylated monoclonal PCT‑specific antibody, and a monoclonal PCT‑specific antibody labeled with a ruthenium complexa) react to form a sandwich complex.
▪ 2nd incubation: After addition of streptavidin-coated microparticles, the complex becomes bound to the solid phase via interaction of biotin and streptavidin.
▪ The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell II M. Application of a voltage to the electrode then induces chemiluminescent emission which is measured by a photomultiplier.
▪ Results are determined via a calibration curve which is instrument specifically generated by 2‑point calibration and a master curve provided via the cobas link.

Expected turn-around time

STAT: 1 hour Urgent: 2 hours Routine: 3 hours

Specimen type

Plasma Lithium Heparin or Serum

Specimen requirements

Container:

SST - Gold Top Tube

PST - Mint Green Top Tube, 3 ml - Lithium Heparin Tube

Green Top White Label, 4 ml - Lithium Heparin Tube

Red Top

Storage and transportation

Specimens may be stored on or off the clot, red blood cell, or separator gel: at room temperature = < 8 hours, or · at 2 - 8°C = < 48 hours

If testing will be delayed more than 72 hours, plasma or serum should be removed from the red cells, clot, or separator gel and stored at -10°C or = < 15 days

Shipping information

The Hospital for Sick Children

Rapid Response Laboratory

555 University Avenue, Room 3642

Toronto, ON

Canada

M5G 1X8

Phone: 416-813-7200

Toll Free: 1-855-381-3212

Hours: 7 days/week, 24 hours/day

Requisition

Procalcitonin, blood - requisition

Background and clinical significance

Procalcitonin (PCT) is a 116 amino acid protein prohormone of calcitonin (CT). Under normal metabolic conditions, hormonally active CT is produced and secreted in C - cells of thyroid gland after specific intracellular proteolytic activity. In healthy individuals, the intact PCT is not secreted from the thyroid and levels in the blood are very low. Response to inflammatory stimuli, including bacterial infection, induces an increased expression of the CALC-I gene production and secretion of intact PC from all parenchymal and differentiated cell types throughout the body. An increase in circulating PCT can be observed 2- 4 hours after bacterial induction and it may increase up to several hundred ug/ L in severe sepsis and septic shock.