CRP Point of Care Testing:
in infections & COPD?
@jochencals
IPCRG Amsterdam
Conflicts of interest
None to declare
Principle investigator on 2 CRP trials
IPCRG Research Needs Statement
Allergic rhinitis
Respiratory tract
infections
Astma
Tobacco
dependence
COPD
Pinnock, PCRJ 2010
Pinnock, PCRJ 2010
Common conditions in GP
1
Upper RTI (R74)
51 /1000
2
Cough (R05)
34/1000
8
Acute sinusitis (R75)
22/1000
9
Acute bronchitis (R78)
22/1000
12 Otitis media (H71)
~15-20% of GP workload
16/1000
Antibiotics for RTI
Cosby Lancet Inf Dis 2007
Solutions to target overprescribing
Disease perspective:
• Point of care tests
Illness perspective:
• Communication tools
• Delayed prescribing
Point of care tests – where?
Melbye PCRJ 2011
CRP POCT decreases antibiotic use for
respiratory infections in primary care
CRP point of care test
•
•
•
•
•
C-reactieve protein
Infection marker
Sensitive, non-specific
Finger prick, one drop of blood
Results < 2-4 minutes (<8 to 250 mg/l)
CRP in RTI– trial evidence
Melbye, Tidsskr Nor Laeg 1995
239 pt LRTI
Norway
Antibiotics 60% → 56%
Diederichsen, Scand J PHC 2000
812 pt RTI
Denmark
Antibiotics 46% → 43%
Cals, BMJ 2009
431 pt LRTI
Netherlands
Antibiotics 68% → 39%
CRP in RTI– trial evidence
Cals, Ann Fam Med 2010
258 pt LRTI & rhinosinusitis
Netherlands
Antibiotics 58% → 43%
Little, Lancet 2013
4264 pt RTI/acute cough
UK, NL, Belgium, Poland, Spain
Antibiotics 48% → 33%
Andreeva, BMC Fam Pract 2014
179 pt acute cough/RTI
Russia
Antibiotics 59% → 38%
Cochrane Database of Systematic Reviews
6 NOV 2014 DOI: 10.1002/14651858.CD010130.pub2
http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD010130.pub2/full#CD010130-fig-0004
CRP in RTI
Use of C-reactive protein point-of-care tests as an adjunct to clinical
examination likely reduces antibiotic use in primary care patients with acute
(lower as well as upper) respiratory infections without affecting patient
recovery rates or the duration of illness. However, a possible small increased
risk of hospitalisation cannot be ruled out and safety-netting should accompany
use of a point-of-care C-reactive protein test.
At present C-reactive protein is the only point-of-care biomarker available in
primary care settings that may assist in guiding antibiotic prescribing for ARIs
Aabenhus, Cochrane Review 2014
CRP assistance
< 20
mg/L
no antibiotic
20-99
mg/L
delayed antibiotic
> 100
mg/L
antibiotic
Add CRP to clinical findings!
Is CRP POCT cost-effective?
Cals, J Ev Clin Pract 2010
Oppong, BJGP 2013
Hunter, Adv Ther 2014
Netherlands
Europe
UK
Additional cost pp of the CRP test is outweighed
by the associated cost savings and QALY
increment associated with a reduction in
infections in the long term
Do GPs want CRP POCT?
•
•
•
•
Cross-sectional survey
Needs assessment of point of care tests
2771 physicians
UK, US, Belgium, the Netherlands and Australia
CRP POCT current use: 19% (range 3-45%)
CRP POCT future use: 55% (range 38-75%)
Howick, BMJ Open 2014
What about CRP POCT in COPD?
• Limited evidence, no RCTs
Strykowksi, Fam Pract 2015
• 952 patients with acute exacerbation of COPD
• Interventions: info and meetings or info and meetings + CRP
• GPs who had access to CRP POCT prescribed significantly less
antibiotics (OR 0.35, 95% CI 0.18-0.68)
Miravitlles, Chest 2013
• Increased sputum purulence and CRP > 40 mg/l
PICO for The PACE Study
Participants
Patients consulting with
AECOPD in primary care
CRP POCT plus training in
Intervention interpretation + current best
practice
Control Current best practice
COPD health status at 2 weeks
Outcomes Antibiotic consumption within
4 weeks
Target sample size: 650 participants from 60 practices
Currently recruited: ~400 patients
CRP POCT
• Effective in reducing AB prescribing
• (L)RTI / acute cough
• No trial evidence in AECOPD
Thank you
@jochencals
j.cals@
maastrichtuniversity.nl
Point of care tests – which test?
C-reactive protein
• Superior to WBC and ESR
• Differentiates serious from self-limiting infections
• Quantitative test result within 4 minutes
Procalcitonin
• Promising in hospital
• Not available as point of care test
Melbye Scan J PHC 1988, Hopstaken BJGP 2003, Cals JAMA 2010
Balancing harms and benefits across settings
Cosby Lancet Inf Dis 2007