RAPID point-of-care infection detection and antibiotic-resistance TESTing enabled with laser-patterned microfluidic devices (RAPID-TEST)

The aim of this proposal is to use our proprietary laser printing technique to develop low-cost, paper-based diagnostic tests addressing a genuine unmet healthcare need, namely the rapid identification of bacterial infections and antibiotic susceptibility profiles to guide therapeutic decision making. Our point-of-care (POC) tests will be suitable for use in a clinic or by the patients themselves as part of a pre-consultation screening process or on-going home monitoring.

We have already developed our paper testing platform and demonstrated excellent microfluidic properties, establishing the proof of principle that the devices can be impregnated with a colorimetric system capable of detecting the inflammatory marker, C-reactive protein. We are now building on this concept for developing excitingly ambitious and conceptually novel diagnostic tests for use at the POC. Our target diseases, urinary tract infections (UTIs) and the chronic airway disease in cystic fibrosis (CF) are in themselves serious and currently sub-optimally managed, but importantly, the successful technology will also be applicable to a large number of other medical and industrial applications.

Bacterial infections affect large numbers of people, with significant quality of life and healthcare cost consequences. There have been very few new antibiotic agents developed over the last 1-2 decades and there is increasing concern over the global epidemic of antimicrobial resistance (AMR). A major part of this problem relates directly to the widespread and indiscriminate use of broad-spectrum, non-targeted antibiotics. Choosing the correct antibiotic is however difficult in the absence of an accurate diagnosis. Current protocols for the identification of an infecting pathogen and follow-on testing of its susceptibility to antibiotics are time-consuming and require specialist microbiology culture-based procedures. These approaches are not only costly and inconvenient, but there is a period of diagnostic uncertainty during which treatment is chosen empirically and may be sub-optimal. Patients' health and well-being is adversely impacted and these delays contribute to the emergence of AMR.

Our proposed novel microfluidics-based devices will uniquely serve a dual purpose - first, rapid, POC identification of a pathogen and second, cheap and expedited testing for its antibiotic resistance profile. We will achieve this through the use of an optimised enzyme-linked immunosorbent assay (ELISA) to produce an immediate colour change on contact with the chosen bacterial antigen. We have selected three problematic bacteria causing UTIs and serious infection in patients with CF. Once single detection systems have been optimised, the next task will be to multiplex them onto the same device. Coupled with the detection system will be chromogenic, agar-based culture wells containing various antibiotics. After a short period of incubation, ~ 24 hours, colour changes will indicate the antibiotics to which the bacteria are resistant. This process would significantly reduce the current diagnostic time of 3-4 days.

These tools will be important and timely for GPs/Consultants in delivering an accurate antibiotic treatment of their patient's infections with significant savings in healthcare costs. For the patients, there will be reduction in symptoms and consequent improvements in quality of life. In the context of CF, a life-long disease, the devices could be used by patients in their own homes for long-term surveillance, in a fashion very aligned with the UK CF Trust's flagship SmartCare programme; this will not only empower patients in self-management, and facilitate earlier treatment, but we may ultimately be able to allow non-infected patients to have contact with each other - lack of real-time knowledge of an individual's infection status currently mandates strict segregation which has a negative impact on patients' well-being.

Rapid point-of-care (POC) diagnostics has a crucial role both in developed and developing countries, due to the increasing strain on the public health system and the lack of resources. Use of on-site POC diagnostics is emerging as a popular choice for non-invasive testing for infections. Rapid identification of pathogens causing such infections is difficult to accomplish, and therefore the current routine practice is initial use of empirical antibiotic treatment which leads to antimicrobial resistance (AMR).

Economic Impact: The UK continues to experience an economic challenge, where large budget cuts due to austerity measures coupled with an ever-increasing demand for better healthcare provision is leading to an unsustainable healthcare scenario. Early-stage testing for bacterial infections and their resistance to antibiotics at the POC, a route proposed via our proposal, will enable crucial savings to the NHS (in terms of equipment, medicine costs and staff) thus shrinking the burden on hospitals via reduced patient trips to A&E units, emergency call outs and hospital admissions that alleviate hospital bed shortages.

Tests developed within the framework of our proposal which enable early-stage testing for infections, such as urinary tract infections which are the most common healthcare associated infections (HCAI) accounting for 17% of all HCAIs, cost approximately £170 million/year in England and constitutes up to 3% of all GP primary care consultations and for those patients needing hospital admissions, extending the average length of hospital stay by 6 days, accounting for an extra 800,000 bed days annually.

Such transformative screening diagnostic tools are being sought after by medical specialists, and this is the motivation of the proposed research, which will therefore translate into huge financial savings for the UK's public health system and its economy.

The methodologies proposed will make possible the large-scale manufacture of such paper-based POC tests, which are affordable and therefore would be widely adopted by the NHS and similar organisations abroad. The UK stands to make substantial gains therefore from the economic benefits that would ensue.

Societal Impact: As stated in the O'Neill report, diagnostic tests (such as those proposed by us) should be an important measure (Intervention no. 5) that must be adopted urgently to reduce the demand for antimicrobials, essentially antibiotics, and thus tackle the problem of AMR. To support this, governments, regulators and other health system leaders should consider incentives to facilitate the uptake and use of rapid POC diagnostics in primary and secondary care because they can also facilitate prompt exchange of invaluable clinical information between healthcare professionals and their patients from the comforts of their homes, which in some cases could be in inaccessible locations. Such remote testing removes the possibility of contracting infections from hospital visits. Since a timely exchange of clinical data could potentially be very useful in early detection and prevention of life-threatening infections, diseases or conditions, the wide societal benefits would not just be in saving lives but also improving the quality of life.

These rapid, dipstick-like tests, which lead to early detection of bacterial infections and testing for antibiotic-susceptibility, will facilitate prompt, accurate antibiotic prescriptions, potentially transforming treatments of millions of patients and minimising the threat of AMR. The tests are designed to be affordable and easy to use, becoming a routine part of primary and secondary care, outpatient settings and hospital screening for all patients. Furthermore, the applicability of low-cost, disposable paper-based testing developed via this project could also be extended to include testing for screening of food pathogens and environmental toxins, all of which inarguably have massive societal benefits.