Clinical Significance of Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis of Urinary Proteins in Preeclampsia

Abstract

Objective: To establish the correlation between clinical and biochemical parameters and the urinary patterns of proteinuria detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) in preeclampsia.

Methods: 34 severe preeclamptics (BP ± 110 mm Hg diastolic and s= + + proteinuria) who were < 34 weeks gestational age were included in the study. Blood and urinary samples were obtained and the following tests performed: full blood count, serum urea, electrolytes and urates, 24-h proteinuria and creatinine clearance, and SDS PAGE.

Results: The patients were divided into two groups depending on whether they excreted only albumin or both tubular and glomerular proteins as detected by SDS PAGE. There were no significant differences in maternal age, parity, gravidity, and gestational age between the groups. Systolic and diastolic blood pressures were significantly higher in those who excreted both glomerular and tubular proteins than in those who excreted albumin only: 173/116 versus 156/106 mm Hg; P = 0.0167. There were no statistical differences between the groups in relation to hemoglobin, platelets, urea, creatinine, or 24-h urinary protein and creatinine clearance values.

Conclusion: The present study shows that SDS PAGE analysis of urinary proteins reveals two distinct patterns of proteinuria. Patients with mixed pattern (tubular and glomerular proteins) have higher blood pressure values than those who excrete albumin only. SDS PAGE appears to be a good noninvasive method of assessing severity of preeclampsia. It may be of value in identifying those patients who require postpartum renal biopsies.

Key Words:

• Severe preeclampsia
• Sodium dodecyl polyacrylamide gel electrophoresis
• Urinary patterns