Plasma concentration of urate, urea and creatinine in Nigerian primigravidae with pre-eclampsia.

Single estimations of plasma urea, uric acid and creatinine were made in late pregnancy in 34 Nigerian primigravidae with mild/moderate or severe pregnancy-induced hypertension, and in 34 matched primigravidae with uncomplicated pregnancy. The differences in mean plasma concentrations of uric acid and creatinine between the pre-eclamptic patients and the normotensive controls were statistically significant, while that in mean urea levels was not. Patients with severe (proteinuric) pre-eclampsia showed significantly higher plasma urea and urate concentrations than women with mild/moderate (aproteinuric) disease, but the difference in mean plasma creatinine values between the two groups was not significant. In the pre-eclamptic group, changes in the plasma concentrations of the substances were more prominently correlated with the degree of proteinuria than the level of hypertension. Of the three substances examined, changes in the blood urate concentrations were the most pronounced. The slight fall in the mean blood urea level in patients with mild/moderate pre-eclampsia followed by an abrupt and significant rise as pre-eclampsia became severe might reflect variations in fluid distribution rather than raised urea production or impaired excretion. High blood uric acid and urea levels in women with proteinuric pre-eclampsia are associated with increased fetal risk and should be an indication for closer monitoring of the function of the feto-placental unit.