Comparison of the Standard 24-hour Urine Protein With Shorter Collection Periods for the Diagnosis of Preeclampsia

Background and project rationale:

Preeclampsia is a common complication of pregnancy, affecting 6-8% of all pregnancies and constitutes a leading cause of maternal morbidity and mortality. Preeclampsia is liable to endanger the lives of both the gravida and the fetus, particularly if treatment is initiated inappropriately or in an untimely fashion.

Diagnosis of preeclampsia is dependent on the finding of proteinuria, determined as being over 300mg of protein in a 24 hours urine sample. However, urine collection spanning 24 hours sometimes constitutes a "bottleneck", extending the time to diagnosis of preeclampsia. Additionally, the collection of urine for 24 hours entails a degree of discomfort, requiring that the woman be in proximity to for collection vessel, and increases the length of her hospital admission.

The use of an abbreviated test may permit diagnosis and treatment in a more timely fashion. Similarly, the ability to exclude the diagnosis more rapidly could reduce length of hospital stay and consumption of the health system's limited resources. Further, a shorter test may reduce the discomfort associated with the 24-hour test and thus increase compliance.

Previous research has suggested that briefer tests correlate with the traditional 24 hour urine collection, however these studies were based on small study populations.

Research Objective:

To validate a brief and rapid test for the diagnosis of urinary protein excretion.

To assess whether, in women with suspected preeclampsia, a difference exists between protein excretion during the daytime and at night.

Methods:

Urine collection will be performed on pregnant women admitted for investigation of suspected preeclampsia, with volumes recorded and samples taken at 6, 12 and 24 hour intervals for assessment of urinary protein content. As such, a comparison will be made between the protein excretion after 6 and 12 hours with that over a full 24 hour period; in addition, comparison will be made between daytime and nighttime urinary protein excretion. The results will allow for assessment of whether a shorter test can substitute the full 24 hour collection in the diagnosis of preeclampsia; results of women who are shown to not suffer from preeclampsia will be used to assess whether a short test can rule out the disease. Additionally a urine sample for protein/creatinine ratio will be examined and correlated with results of the different collection periods.