PT  - JOURNAL ARTICLE
AU  - Jesper Lykkegaard
AU  - Jonas Kanstrup Olsen
AU  - Rikke Vognbjerg Sydenham
AU  - Malene Plejdrup Hansen
TI  - C-reactive protein cut-offs used for acute respiratory infections in Danish general practice
AID  - 10.3399/bjgpopen20X101136
DP  - 2021 Jan 01
TA  - BJGP Open
PG  - bjgpopen20X101136
VI  - 5
IP  - 1
4099  - http://bjgpopen.org/content/5/1/bjgpopen20X101136.short
4100  - http://bjgpopen.org/content/5/1/bjgpopen20X101136.full
SO  - BJGP Open2021 Jan 01; 5
AB  - Background GPs can use the C-reactive protein (CRP) point-of-care test (POCT) to assist when deciding whether to prescribe antibiotics for patients with acute respiratory tract infections (RTIs).Aim To estimate the CRP cut-off levels that Danish GPs use to guide antibiotic prescribing for patients presenting with different signs and symptoms of RTIs.Design & setting A cross-sectional study conducted in general practice in Denmark.Method During the winters of 2017 and 2018, 143 GPs and their staff registered consecutive patients with symptoms of an RTI according to the Audit Project Odense (APO) method. CRP cut-offs were estimated as the lowest level at which half of the patients were prescribed an antibiotic.Results In total, 7813 patients were diagnosed with an RTI, of whom 4617 (59%) had a CRP test performed. At least 25% of the patients were prescribed an antibiotic when the CRP level was >20 mg/L, at least 50% when CRP was >40 mg/L, and at least 75% when CRP was >50 mg/L. Lower thresholds were identified for patients aged ≥65 years and those presenting with a fever, poor general appearance, dyspnoea, abnormal lung auscultation, or ear/facial pain, and if the duration of symptoms was either short (≤1 day) or long (>14 days).Conclusion More than half of patients presenting to Danish general practice with symptoms of an RTI have a CRP test performed. At CRP levels >40 mg/L, the majority of patients have an antibiotic prescribed.