Why Serum Uric Acid is Requested for Preeclampsia
Serum uric acid is requested in preeclampsia primarily for prognostic risk stratification rather than diagnosis, as elevated gestation-corrected levels are associated with worse maternal and fetal outcomes including severe hypertension, hepatic dysfunction, preterm delivery, and fetal growth restriction. 1
Role in Clinical Assessment
Prognostic Value, Not Diagnostic Criterion
- Serum uric acid is explicitly not a diagnostic criterion for preeclampsia, but serves as a prognostic marker when elevated. 1
- The International Society for the Study of Hypertension in Pregnancy (ISSHP) recommends measuring uric acid as part of baseline testing in all women with chronic hypertension or suspected preeclampsia to establish a reference point for monitoring disease progression. 1
- Elevated gestation-corrected uric acid levels should prompt detailed assessment of fetal growth, even in women with gestational hypertension alone. 1
Association with Adverse Outcomes
- Higher uric acid levels correlate with severe preeclampsia, hepatic dysfunction, and preterm delivery, making it useful for identifying high-risk patients who require intensified monitoring. 2
- Women with preeclampsia require at least twice-weekly monitoring of uric acid alongside hemoglobin, platelet count, liver enzymes, and creatinine to detect progressive organ dysfunction. 1, 3
- Elevated uric acid is associated with increased risk of maternal complications including severe hypertension, eclampsia, and cesarean section, as well as fetal complications like small-for-gestational-age infants. 4, 5
Critical Limitations and Pitfalls
What Uric Acid Should NOT Be Used For
- Uric acid should never be used alone to determine the timing of delivery—this is a critical pitfall that must be avoided. 1, 3
- Do not use uric acid level as an indication for delivery, as serious organ dysfunction can develop at various uric acid levels. 2, 6
- Uric acid lacks sufficient sensitivity and specificity to serve as a standalone predictor of maternal and fetal complications. 4, 5
Proper Clinical Context
- Uric acid must be interpreted alongside other markers including blood pressure, proteinuria, platelet count, liver enzymes, and creatinine as part of comprehensive preeclampsia assessment. 2, 3
- The test provides additional prognostic information but should never replace clinical judgment or other established criteria for management decisions. 1
- While research shows associations between elevated uric acid and adverse outcomes, the overall quality of evidence for its predictive accuracy is low, with systematic reviews showing it is a poor predictor when used in isolation. 4, 5
Pathophysiological Rationale
- Hyperuricemia in preeclampsia results from reduced uric acid clearance due to diminished glomerular filtration, increased tubular reabsorption, and decreased secretion. 7
- Elevated uric acid may contribute directly to preeclampsia pathogenesis by promoting inflammation, oxidative stress, and endothelial dysfunction, though it is often considered secondary to altered kidney function. 8
- The elevation in uric acid can precede clinical manifestations of preeclampsia, making it potentially useful for early risk assessment when combined with other clinical parameters. 8