Use of the FebriDx point-of-care test for lower respiratory tract infections in primary care: a qualitative interview study

Abstract

Background: FebriDx is a single-use, analyser-free, point-of-care test with markers for bacterial (C-reactive protein [CRP]) and viral (myxovirus resistance protein A [MxA]) infection, measured on a finger-prick blood sample.

Aim: As part of a larger feasibility study, we explored the views of healthcare professionals (HCPs) and patients on the use of FebriDx to safely reduce antibiotic prescriptions for lower respiratory tract infections (LRTIs) in primary care.

Design & setting: Remote semi-structured qualitative interviews were conducted in South England.

Method: In total, 22 individuals (12 patients who underwent FebriDx testing and 10 HCPs from general practices that conducted testing) participated in interviews, which were analysed thematically.

Results: Patients and HCPs expressed positive views about use of the test. They felt FebriDx was a useful tool to inform prescribing decisions and provided a visual aid to support shared decision making and appropriate antibiotic use. Most felt it would be feasible to integrate use into routine primary care consultations. Some practical difficulties with blood collection and interpreting results, which impacted on usability, were identified. Some patients' reactions to negative test results suggested the need for better communication alongside use of the test.

Conclusion: FebriDx was perceived as a useful tool to guide antibiotic prescribing and support shared decision making. Initial practical problems with testing and communicating results are potential barriers to use. Training and practice on using the test and effective communication are likely to be important elements in ensuring patient understanding and satisfaction, and successful adoption.

Keywords: diagnosis; infectious illness; point-of-care testing; qualitative research.

Figure 1.. The FebriDx device and its possible results. A) The FebriDx device; B) a negative result with a blue control line; C) a grey line indicating positive C-reactive protein (CRP) (lower limit of detection [LLoD] 20 mg/l); D) a red line indicating positive myxovirus resistance protein A (MxA) (LLoD 40 ng/ml); and E) all lines present indicating both CRP and MxA positive. The presence of a grey CRP line with no red MxA line is suggestive of a bacterial infection. A red MxA line is suggestive of a viral infection. The presence of both CRP and MxA is suggestive of viral infection, but doesn’t exclude a concurrent bacterial infection. A negative test result (no grey or red lines) indicates an undetectable level of either CRP or MxA. In most cases, this suggests a lack of significant host response to infection, most likely because the illness is minor or the patient is in the recovery phase of their illness.