In a pregnant patient beyond 20 weeks gestation with new‑onset hypertension and proteinuria, can preeclampsia cause an increase in serum creatinine?

Can Preeclampsia Cause an Increase in Creatinine?

Yes, preeclampsia definitively causes elevated serum creatinine as a manifestation of maternal renal dysfunction, and this is one of the diagnostic criteria for preeclampsia with severe features. 1, 2

Creatinine Elevation as a Diagnostic Feature

Elevated serum creatinine (≥1.1 mg/dL or twice the baseline value) is an established criterion for diagnosing preeclampsia with severe features. 1 The International Society for the Study of Hypertension in Pregnancy (ISSHP) 2018 guidelines explicitly include renal insufficiency as one of the maternal organ dysfunction criteria that, when present with new-onset hypertension after 20 weeks, confirms the diagnosis of preeclampsia. 1

Specific Diagnostic Thresholds

• Creatinine ≥1.1 mg/dL indicates severe features of preeclampsia 1
• Doubling of baseline creatinine from pre-pregnancy or early pregnancy values also indicates severe disease 1
• Baseline serum creatinine should be measured at first prenatal visit in all women with chronic hypertension to establish reference values for detecting superimposed preeclampsia 1, 2

Pathophysiology of Renal Involvement

The renal dysfunction in preeclampsia represents poor organ perfusion and systemic endothelial damage characteristic of this multisystem disorder. 1 Normal pregnancy increases glomerular filtration rate by 40-50% above baseline by 24 weeks gestation, which typically decreases serum creatinine. 2 When preeclampsia develops, this physiologic adaptation is disrupted, leading to:

• Impaired renal perfusion from systemic vasoconstriction 1
• Glomerular endotheliosis (the pathognomonic renal lesion of preeclampsia)
• Reduced glomerular filtration rate
• Consequent elevation in serum creatinine 2

Clinical Significance and Risk Stratification

Elevated creatinine in preeclampsia carries significant prognostic implications:

• Serum creatinine ≥0.7 mg/dL is associated with nearly 3-fold increased risk of early-onset superimposed preeclampsia (before 34 weeks) in women with chronic hypertension (adjusted OR 2.89,95% CI 1.63-5.13) 3
• Each incremental increase in creatinine level further increases risk of early-onset disease 3
• Renal dysfunction is more strongly associated with early-onset rather than late-onset preeclampsia, suggesting it plays a central role in the pathophysiology of severe disease 3

Monitoring and Management Approach

Initial Assessment

When preeclampsia is suspected in a woman with new-onset hypertension after 20 weeks:

• Measure serum creatinine, electrolytes, and uric acid as part of baseline laboratory evaluation 1
• Obtain complete blood count (hemoglobin, platelets) 1
• Check liver enzymes (AST, ALT, LDH) and function tests 1
• Quantify proteinuria with 24-hour collection or protein-to-creatinine ratio 1
• Perform renal ultrasound if serum creatinine or urine testing is abnormal 1, 2

Ongoing Surveillance

For women with chronic hypertension at risk for superimposed preeclampsia:

• Establish baseline creatinine in first trimester to detect subsequent changes 1, 2
• Up to 25% of women with chronic hypertension will develop superimposed preeclampsia 1
• Monitor for sudden increases in blood pressure requiring medication escalation 1
• Assess for new or worsening proteinuria (≥50% increase from baseline or protein-to-creatinine ratio ≥0.5 with baseline ≥0.3) 1

Critical Pitfalls to Avoid

Do not dismiss modest creatinine elevations in pregnancy. While a creatinine of 1.1 mg/dL might be considered normal outside pregnancy, it represents significant renal dysfunction in a pregnant woman whose baseline should be substantially lower (typically 0.4-0.8 mg/dL due to increased GFR). 2

Recognize that severe preeclampsia can occur without severe hypertension. In UK data, 34% of eclamptic women had maximum diastolic blood pressure ≤100 mmHg. 1 Therefore, elevated creatinine with modest blood pressure elevation still warrants aggressive management.

Understand that renal involvement indicates need for delivery planning. When creatinine elevation occurs as part of preeclampsia with severe features, this represents maternal organ dysfunction requiring close monitoring and often expedited delivery, balancing maternal renal health against fetal maturity. 1, 2

Long-term Implications

Women who develop preeclampsia with renal involvement have increased risk of subsequent kidney disease. At mean 7.1 years postpartum, 31% of women with history of preeclampsia had microalbuminuria compared to 7% with uncomplicated pregnancies—a 4-fold increased risk. 4 This underscores the importance of recognizing and documenting renal dysfunction during the acute preeclamptic episode for long-term cardiovascular and renal risk stratification.