point of care C-reactive protein (CRP) use in primary care with patient with lower respiratory tract infection ( community acquired pneumonia (CAP) )

Last reviewed 10/2020

Point of care C-reactive protein (CRP) use in primary care with patient with lower respiratory tract infection (community acquired pneumonia (CAP)

• for people presenting with symptoms of lower respiratory tract infection in primary care, consider a point of care C-reactive protein test if after clinical assessment a diagnosis of pneumonia has not been made and it is not clear whether antibiotics should be prescribed (1)
  • use the results of the C-reactive protein test to guide antibiotic prescribing in people without a clinical diagnosis of pneumonia as follows:
    
    
    • do not routinely offer antibiotic therapy if the C-reactive protein concentration is less than 20 mg/litre
      
      
    • consider a delayed antibiotic prescription (a prescription for use at a later date if symptoms worsen) if the C-reactive protein concentration is between 20 mg/litre and 100 mg/litre
      
      
    • offer antibiotic therapy if the C-reactive protein concentration is greater than 100 mg/ litre

Notes:

A systematic review and meta-analysis of primary care studies pointed to a role of point of care testing for CRP in significantly reducing antibiotic prescribing at the index consultation for patients with RTIs (2)

• most patients consulting in general practice have CRP levels less than 20 mg/L
  • by avoiding the administration of antibiotics to patients with such low CRP values, unnecessary use of antibiotics may be reduced (3)

Reference:

• 1) NICE (December 2014).Pneumonia- Diagnosis and management of community- and hospital-acquired pneumonia in adults
• 2) Huang Y, Chen R, Wu T, Wei X, Guo A. Association between point-of-care CRP testing and antibiotic prescribing in respiratory tract infections: a systematic review and meta-analysis of primary care studies. Br J Gen Pract. 2013;63:e787-e794. doi: 10.3399/bjgp13X674477
• 3) Cals JW, Schot MJ, de Jong SA, Dinant GJ, Hopstaken RM. Point-of-care C-reactive protein testing and antibiotic prescribing for respiratory tract infections: a randomized controlled trial. Ann Fam Med. 2010;8:124-133. doi: 10.1370/afm.1090