QuikRead go for C-reactive protein testing in primary care

Specialist commentator comments

Three specialist commentators considered that the QuikRead go CRP point-of-care test would be done for patients presenting with symptoms of respiratory tract infections, because there is only evidence for the diagnosis of this indication in primary care. It may also be used for some inflammatory conditions, such as arthritis or polymyalgia rheumatica.

The main system benefit of point-of-care technology for C-reactive protein (CRP) testing may not be quantifiable in terms of cost savings due to reduced antibiotic usage. Instead, the benefits from using point-of-care tests would be in helping the safe and appropriate prescribing of antibiotics, and in improving clinical care.

One commentator noted that there is evidence to show that delayed antibiotic prescriptions reduce consultations. They felt that point-of-care CRP testing may similarly reduce future presentations with similar illnesses, but were unsure whether there is evidence for this. The QuikRead go CRP test could possibly prevent accident and emergency attendance by those patients who feel they need antibiotics and have not been given them by their primary care clinician. It could also improve sensitivity in diagnosing pneumonia in some vulnerable patients so that effective treatment can be given to avoid hospital admissions.

One commentator noted a range of factors, which may influence results and should be accounted for in any point-of-care test. For example, it is unclear whether testing whole blood, serum and plasma could give different results. The commentator also mentioned the hook effect, where beyond a critical concentration of CRP (the hook point), the signal level decreases as the CRP concentration increases. The manufacturer's instructions for use show that CRP concentrations less than 1000 mg/litre do not give falsely low results. However, the commentator was concerned that this may imply that CRP concentrations above 1000 mg/litre give falsely low results and it may be difficult to determine when this is the case. The commentator felt that there should be more technical awareness around these tests in users.