The clinical utility of serum uric acid measurements in pre-eclampsia and transient hypertension in pregnancy.

BACKGROUND: Our purpose was to evaluate the clinical utility of serum uric acid measurements in the hypertension diseases of pregnancy.

METHODS: We identified 286 women and categorized them into three diagnostic groups according to definitions of hypertensive diseases in pregnancy published by the National Working Group on Hypertension in Pregnancy: pre-eclampsia (94), transient hypertension (102) and normal (90). We compared the median uric acid concentration for each group and calculated the sensitivities and the specificities in diagnosing pre-eclampsia. The results were analyzed by the Mann-Whitney test.

RESULTS: Median serum uric acid values in the pre-eclamptic group, in the transient hypertension group and in the control group were 375 (262-536) mumol/L, 309 (214-387) mumol/L, 259 (143-339) mumol/L, respectively. Compared with normal, the median serum uric acid levels in women with pre-eclampsia or transient hypertension were significantly elevated. Differences in median serum uric acid concentrations between women with preeclampsia and with transient hypertension were statistically significant too. The prevalence of IUGR in the pre-eclamptic group and transient hypertension group was 65.9% and 29.4%, respectively. Sensitivity for serum uric acid levels of 339 mumol/L was 77.3% in the pre-eclamptic group and 32.3% in the transient hypertension group; the difference was statistically significant. Specificity was exactly the same in both groups (92%).

CONCLUSIONS: Our data, in accordance with international literature, confirm the clinical utility of serum uric acid as a marker of pre-eclampsia, but not of transient hypertension. Furthermore its high predictive value makes it possible to select a group of pre-eclamptic women with high risk for intrauterine growth retardation.