C-reactive protein to initiate or withhold antibiotics in acute respiratory tract infections in adults, in primary care: review.

BACKGROUND: There is a discrepancy between the incidence of viral pathogens and the frequency of prescribing antibiotics for acute respiratory tract infections (ARTIs). Typically, primary care physicians have few possibilities to order sophisticated laboratory tests to help distinguish viral pathogens from bacterial pathogens. C-Reactive Protein (CRP) measurement could help the primary care physician to discriminate more easily between these two conditions, and should contribute to reducing unnecessary prescribing of antibiotics during the first patient consultation.

METHODS: A literature review was performed in order to see what is known and tested about CRP measurement in ARTIs in adult patients in the primary care setting, to assist GPs in their decision whether or not to prescribe antibiotics.

RESULTS: Out of 54 entered articles reviewed from 109 abstracts, we could identify 8 articles which correspond to our selection criteria. Overall the methodological quality of the studies is heterogeneous. Specificity and sensibility of CRP measurement in ARTIs in adults vary widely from as low as 10% to as high as 99%.

DISCUSSION AND CONCLUSION: Current literature is insufficient and too heterogeneous to allow conclusions about the value of CRP measurement to support the decision of prescribing antibiotics for ARTIs in adults, in primary care. Most studies tested CRP in view of an aetiological diagnosis of ARTIs, whereas common practice in primary care is oriented pragmatically towards risk management and watchful waiting when 'dangerous' symptoms are absent. We found sufficient evidence that CRP would be a useful biomarker in this perspective, but thorough and rigorous studies are needed to test this hypothesis.