Urinary podocalyxin as a marker of preeclampsia in a Hispanic population

Int J Physiol Pathophysiol Pharmacol. 2014 Jul 12;6(2):115-24. eCollection 2014.

Abstract

Background: Preeclampsia is associated with significant materno-fetal morbidity and mortality. Podocyturia due to podocyte damage seems to be associated with the disease. The objective of this study was to evaluate the usefulness of urinary podocalyxin as a marker of preeclampsia in a Hispanic population.

Methods: 63 patients were studied. 25 patients had preeclampsia/eclampsia (PE-E). 38 patients had normal pregnancies and served as control group. 24 hour proteinuria, urine protein/creatinine (UPC), urinary podocalyxin and perinatal outcomes were measured. A Podocalyxin ELISA test was used to detect podocyturia.

Results: Mean age (years), mean±SD was 30.5±5.4 in normal patients vs 30.6±5.8 in PE-E, p=0.98. Median gestational age (weeks) was, 38 (range 21-42) for normal pregnancies and 36 (range 24-40) for patients with PE-E, <0.001. Urine podocalyxin/creatinine on admission (ng/mg), median [IQR] in normal patients was 55.9 [29.4, 74.9] vs 109.7 [63.8, 234.1] in PE-E, p=0.001. After adjusting for admission proteinuria, urinary podocalyxin remained independently associated with preeclampsia: OR=1.0040 (95% CI 1.0003-1.0078), p=0.03. There was low to moderate correlation between UPC and urinary podocalyxin, Spearman's =0.31, p=0.01. In PE-E, post-partum urine podocalyxin was lower, median [IQR]: 69.7 [32.7, 184.8] p=0.19 vs admission. There was a trend towards more podocyturia and proteinuria in patients with eclampsia, comparing to those with preeclampsia. There was no association observed between podocyturia and neonatal mortality, IUGR or Apgar scores.

Conclusions: Significantly higher levels of urinary podocalyxin are seen in preeclampsia/eclampsia. They tend to normalize after delivery.

Keywords: Podocalyxin; biomarkers; hypertension; preeclampsia; proteinuria.