Completed Research

This was a prospective single-centre double-blind non-intervention study conducted from January 2020 to March 2022, in order to evaluate the diagnostic performance and clinical utility of the urine Congo red dot test (CRDT) in predicting preeclampsia (PE) within 7, 14, and 28 days of assessment for women presenting with signs and symptoms of suspected PE after 20 weeks of gestation. In this study, we found that among the 216 women analysed, 78 (36.1%) developed PE, of which only 7 (9.0%) had a positive urine CRDT test. The median (IQR) interval between the initial test and the diagnosis of PE was significantly shorter for women with a positive urine CRDT compared to those with a negative urine CRDT (1 day (0-5 days) vs 8 days (1-19 days), P = 0.027). The negative predictive values of a negative urine CRDT test for PE within 7, 14, and 28 days of assessment were 83.73% (95% CI 81.75%-85.54%), 78.92% (95% CI 77.07%-80.71%), and 71.77% (95% CI 70.06%-73.42%), respectively. The sensitivity of the urine CRDT in ruling in PE within 7, 14, and 28 days of assessment was 17.07% (95% CI 7.15%-32.06%), 13.73% (95% CI 5.70%-26.26%), and 10.61% (95% CI 4.37%-20.64%), respectively. In conclusion, the urine CRDT alone has low sensitivity in the short-term prediction of PE in women with suspected PE. Further studies are required to evaluate its clinical utility when combined with maternal serum anti-angiogenic and pro-angiogenic proteins to improve the short-term prediction of PE.