Development and validation of a rapid point-of-care diagnostic assay for antimicrobial resistance profiling in clinical bacterial isolates using CRISPR-based detection

Project Abstract

Development and validation of a rapid point-of-care diagnostic assay for antimicrobial resistance profiling in clinical bacterial isolates using CRISPR-based detection presents a transformative approach to the timely management of infectious diseases. The study integrates CRISPR-Cas12a/Cas13a collateral cleavage activity with microfluidic sample processing to deliver a portable, cost-effective diagnostic assay capable of simultaneous detection of multiple AMR determinants directly from clinical specimens within 60 minutes. We designed a panel targeting prevalent resistance genes, including bla genes (CTX-M, KPC, NDM), mecA, vanA, and qnr variants, along with species- and mecotype-specific markers to enable precise organism-level attribution. A modular workflow was established (i) rapid sample lysis and nucleic acid extraction optimized for low-volume, resource-limited settings; (ii) isothermal amplification via recombinase polymerase amplification (RPA) to maintain compatibility with field deployment; (iii) CRISPR-CdCas12a/Cas13a guided detection using fluorescent and lateral-flow readouts to accommodate diverse infrastructure; and (iv) integrated data interpretation through a point-of-care reader or smartphone-based interface, ensuring user-friendly operation by non-specialist personnel. Analytical performance was evaluated using well-characterized reference strains and a large, prospectively collected panel of clinical isolates, covering Gram-positive and Gram-negative organisms from bloodstream, respiratory, and urinary samples. The assay demonstrated limits of detection in the femtomolar to attomolar range for target DNA/RNA, with high analytic sensitivity and specificity exceeding 95% across targets. Clinical sensitivity and specificity were assessed against gold-standard culture and molecular methods, revealing robust concordance for key resistance determinants, particularly blaCTX-M, mecA, and vanA. Cross-reactivity analyses confirmed assay specificity, with negligible signals from non-target organisms and common commensals. The assay’s multiplexing capacity enabled parallel reporting of resistance profiles and species identification, facilitating rapid therapeutic decision-making in empiric and targeted therapy contexts. To address diverse settings, we embedded quality control measures, including internal amplification controls and external positive/negative controls, and conducted rigorous matrix validation across simulated and real-world sample types. The study also evaluated integration potential into existing antimicrobial stewardship workflows, emphasizing reduction in turnaround time, improved de-escalation opportunities, and improved patient outcomes. A cost analysis highlighted per-test expenses substantially lower than conventional molecular platforms, with scalable manufacturing considerations for widespread adoption. User testing in simulated clinic environments demonstrated high acceptability, minimal hands-on time, and straightforward interpretation of results by clinicians and laboratory staff. In conclusion, the developed CRISPR-based POC assay delivers rapid, accurate AMR profiling directly from clinical isolates and specimens, with multiplex capability, adaptable readouts, and compatibility with resource-limited settings. This platform holds promise for accelerating targeted antimicrobial therapy, reducing inappropriate antibiotic use, and enhancing infection control through timely surveillance of resistance patterns. Further multicenter validation and regulatory pathway mapping are recommended to support broader clinical deployment.

Project Overview

What This Project Is About

---

A straightforward, practical look at developing a quick test that can be used in clinics to tell which antibiotics might not work against a bacterial infection. The project combines a modern gene-based detection method with a simple test that can be used at the point of care, meaning in a doctor’s office or bedside, rather than in a full laboratory.

---

---

The Problem It Addresses

---

Antibiotic resistance makes infections harder to treat. Traditional tests can take a day or more to yield results, delaying effective treatment. This project aims to shorten that time by giving clinicians fast, actionable information about resistance patterns directly from patient samples.

---

---

Objectives of the Project

---

1. Develop a rapid, user-friendly assay that detects common resistance markers in bacteria.
2. Validate the assay against standard laboratory methods to ensure accuracy.
3. Assess the test’s speed, cost, and ease of use in real patient-care settings.
4. Demonstrate how results can guide initial antibiotic choices.
5. Identify potential limitations and propose improvements for future versions.

---

---

What You Will Do Step by Step

---

1) Review current resistance targets and select genes to test. 2) Design a CRISPR-based detection readout suitable for rapid results. 3) Develop a simple prototype device or kit for point-of-care use. 4) Collect bacterial samples and run parallel tests with standard methods. 5) Analyze accuracy, sensitivity, and specificity. 6) Evaluate user-friendliness and time to result. 7) Compare costs and scalability. 8) Document findings and propose real-world deployment steps.

---

---

Expected Outcome

A validated, rapid point-of-care test that reliably indicates resistance profiles, enabling quicker, targeted antibiotic treatment and potentially reducing unnecessary broad-spectrum antibiotic use.