Near-patient testing for infection using urinalysis and immuno-chromatography strips

Area of Science:

• Clinical diagnostics
• Microbiology
• Immunology

Background:

• Urinary tract infections (UTIs) diagnosis relies on costly urine cultures, delaying treatment.
• Rapid diagnostic methods are needed to improve patient outcomes and reduce healthcare costs.

Purpose of the Study:

• To evaluate a novel dip-and-read immunochromatography (IC) strip for detecting Escherichia coli (E. coli) in urine.
• To compare the diagnostic accuracy of IC strips with traditional urinalysis dipsticks.

Main Methods:

• Development of an IC strip utilizing anti-E. coli antibodies and fluorescein labeling for bacterial capture and detection.
• Testing of IC strips and combined leukocyte esterase/nitrite dipsticks on urine specimens.
• Analysis of negative and positive predictive values for both methods.

Main Results:

• Leukocyte esterase and nitrite dipsticks showed high negative predictive values (93%) but low positive predictive values for UTIs.
• IC strips demonstrated a negative predictive value of 89% with fewer false positives (higher positive predictive values) than traditional dipsticks.
• Combined use of IC strips and urinalysis dipsticks offered the best diagnostic performance.

Conclusions:

• The IC strip test is a valuable tool for rapid, point-of-care UTI diagnosis.
• This technology has the potential to reduce the reliance on urine cultures, saving resources and time.
• Combining IC strips with urinalysis dipsticks represents an optimal strategy for dipstick-based UTI diagnosis.