Serum Procalcitonin testing in Medical Admissions ( for adults only ) - Protocol for

Publication: 09/06/2017  --
Last review: 01/01/1900  
Next review: 09/06/2020  
Clinical Guideline
CURRENT 
ID: 5057 
Approved By: Improving Antimicrobial Prescribing Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2017  

 

This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

Protocol for Serum Procalcitonin testing in Medical Admissions (for adults only)

Background

Procalcitonin (PCT) is a protein produced in the C-cells of the thyroid gland in levels not normally detectable in the blood. However, during bacterial infection, toxins and cytokines stimulate production of PCT in other cells, leading to rapid increase in plasma levels in around 3-4 hours. It is therefore a sensitive and specific biomarker of bacterial infection.  It has a short half-life of around 24 hours and is not dependent on renal function.

PCT has been used to differentiate bacterial infection from viral infection, fungal infection, autoimmune disease and other causes of SIRS.  Sensitivity and specificity vary between infection site, patient group and cut-off level.  Use of PCT in acute medical patients where bacterial infection was suspected has been shown to safely reduce antibiotic use, without resulting in increases in mortality or clinical failure.

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Indications for testing

PCT levels are used to guide antibiotic use in the following situations;

  • Medical patients admitted within the last 24 hours
  • Patients where infection is suspected but criteria for sepsis not met and there is no confirmed evidence of infection
  • Initiation or discontinuation of antibiotics is being considered
  • On advice from a Microbiologist or Infectious Diseases Specialist

Procalcitonin testing should not be used;

  • Where bacterial infection is highly likely or proven and antibiotics are indicated regardless of PCT result
  • Patients who meet sepsis criteria
  • Patients with significant positive cultures or clearly identified source of infection
  • Severely immunocompromised patients
  • Patients with cystic fibrosis or active tuberculosis

Procalcitonin levels will be increased in the following conditions and therefore cannot be used to guide antibiotic therapy;

  • Surgery within previous 3 days
  • Treatment that acts upon the pro-inflammatory CK cascade (OKT3, injection therapy TNFα, IL-2 and anti-lymphocyte globulins)
  • Some cancers; medullary CT-cell cancers of the thyroid, pulmonary small-cell carcinoma and bronchial carcinoma
  • Prolonged cardiogenic shock or haemorrhage
  • Severe hepatic dysfunction
  • Rhabdomyolysis

There is insufficient evidence for use of PCT monitoring in pregnant women so testing is not recommended.

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Practicalities

Blood should be sent in a yellow-top tube to biochemistry.  PCT testing will be carried out at SJUH, during working hours. Turn-around time is expected to be within 3 hours.  Samples sent out of hours will be analysed the following day.  The request for PCT may be able to be ‘added-on’ to samples taken within 8 hours dependent upon laboratory capacity. Tests cost ~£14 each.

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Result interpretation

PCT testing is used to aid decisions to initiate or discontinue antibiotic use.  The peak level taken within 24 hours of admission should be used as one part of clinical assessment and not in isolation.

Adapted from Royal Hampshire Protocol written by K. Saad et al.

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Flowchart

Provenance

Record: 5057
Objective:
Clinical condition:
Target patient group:

PCT levels are used to guide antibiotic use in the following situations;

  • Medical patients admitted within the last 24 hours
  • Patients where infection is suspected but criteria for sepsis not met and there is no confirmed evidence of infection
  • Initiation or discontinuation of antibiotics is being considered
  • On advice from a Microbiologist or Infectious Diseases Specialist

Procalcitonin testing should not be used;

  • Where bacterial infection is highly likely or proven and antibiotics are indicated regardless of PCT result
  • Patients who meet sepsis criteria
  • Patients with significant positive cultures or clearly identified source of infection
  • Severely immunocompromised patients
  • Patients with cystic fibrosis or active tuberculosis

Procalcitonin levels will be increased in the following conditions and therefore cannot be used to guide antibiotic therapy;

  • Surgery within previous 3 days
  • Treatment that acts upon the pro-inflammatory CK cascade (OKT3, injection therapy TNFα, IL-2 and anti-lymphocyte globulins)
  • Some cancers; medullary CT-cell cancers of the thyroid, pulmonary small-cell carcinoma and bronchial carcinoma
  • Prolonged cardiogenic shock or haemorrhage
  • Severe hepatic dysfunction
  • Rhabdomyolysis

There is insufficient evidence for use of PCT monitoring in pregnant women so testing is not recommended.

Target professional group(s): Secondary Care Doctors
Adapted from:

Evidence base

  1. Prkno et al. Procalcitonin-guided therapy in intensive care unit patients with severe sepsis and septic shock--a systematic review and meta-analysis.
  2. Lin C, Pang Q. Meta-analysis and systematic review of procalcitonin-guided treatment in acute exacerbation of chronic obstructive pulmonary disease. Clin Respir J. 2016;22.
  3. Vikse. Int J Infect Dis 2015;38:68-76Diagnostic Accuracy of Procalcitonin in Bacterial Meningitis Versus Nonbacterial Meningitis: A Systematic Review and Meta-Analysis. Medicine (Baltimore). 2016 Mar;95(11).
  4. Hoeber et al. The diagnostic accuracy of procalcitonin for bacteraemia: a systematic review and meta-analysis. Clin Microbiol Infect. 2015 May;21(5):474-81.
  5. Lee et al. Diagnostic value of procalcitonin for bacterial infection in elderly patients - a
    systemic review and meta-analysis. Int J Clin Pract. 2013 Dec;67(12):1350-7.
  6. Wu et al. Use of serum procalcitonin to detect bacterial infection in patients with
    autoimmune diseases: a systematic review and meta-analysis. Arthritis Rheum. 2012 Sep;64(9):3034-42.
  7. Branche et al Serum procalcitonin and viral testing to guide antibiotic use for respiratory infections in hospitalized adults: a randomized trial J Infect Dis. 2015 212(11):1692-700

Approved By

Improving Antimicrobial Prescribing Group

Document history

LHP version 1.0

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