Screening for proteinuria in hypertensive disorders of pregnancy.

One hundred and fifty patients were recruited to assess the reliability of a random urinary dipstick for protein compared with 24 hour urine analysis and to determine if a shorter interval of collection is reliable in screening for proteinuria in hypertensive disorders of pregnancy. These patients were instructed in the collection technique of a 24 hour urine sample. Aliquots were taken to represent 6 and 12 hour collections. The mean gestational age was 30 weeks and the mean diastolic blood pressure 95 mmHg. Of the patients, 84 had proteinuria and 66 had no proteinuria on random urinary dipstick analysis. The random urinary dipstick showed a sensitivity of 84%, and a specificity of 61%. The urinary dipstick of the hour 6 sample showed a sensitivity of 84.5%, and a specificity of 90.1%. Urine analysis of the 6 hour sample showed a sensitivity of 87.9% and a specificity of 80.4%. Analysis of the 12 hour sample yielded an accuracy of approximately 83%. The random urinary dipstick is unreliable in screening for proteinuria in hypertensive disorders of pregnancy. A 6 hour collection is much more accurate.