PP025. Urinary dipstick proteinuria testing - Does automated strip analysis offer an advantage over visual testing?

Area of Science:

• Obstetrics and Gynecology
• Clinical Chemistry
• Diagnostic Accuracy Studies

Background:

• Visual urinary test strips are common for screening proteinuria in pregnancy due to cost and convenience.
• However, visual test strips have known limitations in sensitivity and specificity.
• Automated readers were recommended by NICE guidelines to improve proteinuria detection accuracy.

Purpose of the Study:

• To compare the diagnostic accuracy of automated versus visual urine dipstick testing.
• The study focused on detecting a random protein:creatinine ratio (PrCr) of ⩾30mg/mmol.

Main Methods:

• A prospective cohort study evaluated 233 urine samples from 160 pregnant women (inpatients and outpatients).
• Urine samples were split for point-of-care visual and automated dipstick testing and laboratory analysis of protein and creatinine.
• Diagnostic test properties were determined by comparing dipstick results to a laboratory-confirmed random PrCr ⩾30mg/mmol.

Main Results:

• Both visual and automated dipstick testing demonstrated low sensitivity (56.0% and 53.9%, respectively).
• Positive likelihood ratios (LR+) were high for both methods (15.0 and 24.6).
• Negative likelihood ratios (LR-) were fair to poor for both (0.46 and 0.47).

Conclusions:

• Automated dipstick urinalysis offers no significant sensitivity advantage over visual testing for proteinuria in a predominantly outpatient pregnancy setting.
• While both methods have strong positive predictive power, their negative predictive power is limited.
• The performance of automated systems may depend on the specific test strips and analysers employed.