An Intact Cell Bioluminescence-Based Assay for the Simple and Rapid Diagnosis of Urinary Tract Infection

Abstract

Urinary tract infection (UTI) is one of the most common infections, accounting for a substantial portion of outpatient hospital and clinic visits. Standard diagnosis of UTI by culture and sensitivity can take at least 48 h, and improper diagnosis can lead to an increase in antibiotic resistance following therapy. To address these shortcomings, rapid bioluminescence assays were developed and evaluated for the detection of UTI using intact, viable cells of Photobacterium mandapamensis USTCMS 1132 or previously lyophilized cells of Photobacterium leiognathi ATCC 33981™. Two platform technologies—tube bioluminescence extinction technology urine (TuBETUr) and cellphone-based UTI bioluminescence extinction technology (CUBET)—were developed and standardized using artificial urine to detect four commonly isolated UTI pathogens—namely, Escherichia coli, Proteus mirabilis, Staphylococcus aureus, and Candida albicans. Besides detection, these assays could also provide information regarding pathogen concentration/level, helping guide treatment decisions. These technologies were able to detect microbes associated with UTI at less than 105 CFU/mL, which is usually the lower cut-off limit for a positive UTI diagnosis. Among the 29 positive UTI samples yielding 105–106 CFU/mL pathogen concentrations, a total of 29 urine specimens were correctly detected by TuBETUr as UTI-positive based on an 1119 s detection window. Similarly, the rapid CUBET method was able to discriminate UTIs from normal samples with high confidence (p ≤ 0.0001), using single-pot conditions and cell phone-based monitoring. These technologies could potentially address the need for point-of-care UTI detection while reducing the possibility of antibiotic resistance associated with misdiagnosed cases of urinary tract infections, especially in low-resource environments.

Optimization of artificial urine formula for in vitro cellular study compared with native urine

“…The AU formula used for such investigations was AU-Siriraj, which has been documented as one of the most physiologic AU formulas available to date [1]. This physiologic AU formula has been widely used in several recent biomedical studies [2][3][4][5][6][7][8][9][10][11][12]. It is suitable for secretome analysis and the study that avoids contaminations of exogenous proteins (i.e., evaluation of secretory endogenous cytokines/chemokines) [14][15][16].…”

“…One of those is our previously established formula, AU-Siriraj, which has been proven as one of the most physiologic AU formulas compared with the other protocols [1]. As such, the AU-Siriraj formula has been widely used in several recent studies for disease mechanisms [2], diagnostics [3], biomarker discovery [4], drug delivery [5][6][7][8][9], crystallization and crystal growth [10], biosensors/bioelectronics [11,12], etc. Moreover, a recent study has shown that AU-Siriraj can improve the polarization features of renal tubular epithelial cells using a Transwell system [13].…”

Microfluidic systems for infectious disease diagnostics

“…Clinically relevant metrics for positive UTI diagnosis (≥10 5 CFU mL −1 ) were reached on a time scale of 20 min. 279…”

Solving polymicrobial puzzles: evolutionary dynamics and future directions

“…On the other hand, MWCBs employ whole bacterial cells, often genetically modified, as miniature reactors to quantify or qualify specific metabolites ( Gui et al., 2017 ). For instance, photogenic bacteria like Photobacterium mandapamensis have been employed to detect pathogens causing urinary tract infections (UTIs), such as E. coli , Proteus mirabilis , S. aureus , and C. albicans ( Reyes et al., 2020 ). In cases where bacteria aren’t naturally photogenic, they can be engineered to express reporter genes like luciferase and green fluorescence protein, generating bioluminescence upon the activation of targeted genes ( Martinez et al., 2019 ; Bazhenov et al., 2023 ).…”