Integrated Biosensor Assay for Rapid Uropathogen Identification and Phenotypic Antimicrobial Susceptibility Testing.

Area of Science:

• Biomedical Engineering
• Clinical Microbiology
• Molecular Diagnostics

Background:

• Standard urinary tract infection (UTI) diagnosis via urine culture takes 2-3 days, leading to empiric antibiotic treatment.
• This delay contributes to antibiotic misuse and the rise of resistant pathogens.
• Rapid diagnostic tests for UTIs are needed to improve patient care and antibiotic stewardship.

Purpose of the Study:

• To develop and validate an integrated biosensor assay for UTI diagnosis.
• The assay aims to identify pathogens and perform antimicrobial susceptibility testing (AST).
• Specifically, it determines the minimum inhibitory concentration (MIC) for ciprofloxacin.

Main Methods:

• Urine samples (n=84 Enterobacteriaceae-positive, n=23 culture-negative) were analyzed.
• An electrochemical biosensor array with complementary DNA probes was used.
• Bacterial 16S rRNA was quantified after incubation with and without ciprofloxacin for pathogen ID and MIC determination.

Main Results:

• The biosensor assay achieved 98.5% sensitivity and 96.6% specificity for pathogen identification.
• Categorical and essential agreement for ciprofloxacin MIC was 97.6%.
• Results were comparable to standard culture but in a significantly shorter assay time.

Conclusions:

• An integrated biosensor platform provides microbiological results, including MIC, comparable to standard culture.
• This technology has the potential for rapid molecular diagnosis of UTIs.
• Further automation and clinical studies are needed for translation to clinical practice.