Table 1.
Studies of podocyturia and urinary podocyte markers in pre-eclampsia
| Author and year |
Study groups | Time point(s) | Sample preparation | Podocyte detection Method |
Results |
|---|---|---|---|---|---|
| Garovic et al (2007)76 | 15 PE 16 NL |
< 24 hours before delivery | Podocyte culture | IF for podocin, nephrin, podocalyxin, and synaptopodin | Podocin staining present in 15/15 PE and absent in 16/16 NL Other 3 less sensitive and specific |
| Aita et al (2009)77 | 11 PE 45 NL |
35 weeks 4 days post 1 month post |
Cytospin | IF for podocalyxin | Podocyturia at 35 weeks and 4 days post in PE Almost no podocyturia at 1 month post delivery 9 of 45 controls showed podocyturia 4 days postdelivery Correlation between podocyturia and BP, but not proteinuria |
| Zhao et al (2011)78 | 16 severe PE 3 mild PE 7 NL 7 NP with nephrotic syndrome |
3rd trimester | Podocyte culture | IF for nephrin | Podocyturia present in all cases of severe PE and nephrotic syndrome Podocyturia absent in all NL and all 3 mild PE cases |
| Jim et al (2012)79 | 29 PE 9 GHTN and HTN 9 NL |
< 24 hours before delivery | Cytospin | IF for synaptopodin | Podocyturia in 11 of 29 (38%) of PE, 3 of 9 (33%) with HTN, and 0 of 9 NL Sensitivity = 38%, Specificity = 70% |
| Facca et al (2012)80 | 25 NL 14 PE |
3rd trimester | Cytospin | IF for nephrin | Mean total number of podocytes 0.9 ± 1.6 for NL versus 9.3 ± 16.8 for PE (P=0.212) |
| Kelder et al (2012)81 | 35 PE 5 GHTN 34 NL 12 NP |
31 to 36 weeks gestation | Urine centrifugation TRIzol RNA isolation | RT-PCR for nephrin, podocin, VEGF | Elevated mRNA for nephrin, podocin, VEGF in PE compared to NL and NP Positive correlation between nephrin and VEGF mRNA in PE (r=0.82, P<0.0001) |
| Wang et al (2012)82 | 20 PE 6 HTN 8 NL |
3rd trimester | ELISA of frozen urine supernatant | ELISA for nephrin, podocalyxin, Big-h3, and VEGF | Urinary nephrin, podocalyxin, and Big-h3 levels are increased in PE Urinary Big-h3 levels correlate with levels of nephrin and podocalyxin |
| Chen et al (2013)83 | 14 PE 14 GHTN 13 NL |
< 1 week before delivery | Cytospin | IF for podocalyxin | Number of podocytes was higher in PE compared to GHTN (P<0.05) and NL (P<0.001) |
| Son et al (2013)84 | 43 Severe PE 30 NL |
< 24 hours before delivery | ELISA of frozen urine supernatant | ELISA for nephrin | Urine nephrin higher in severe PE than in NL Urine nephrin correlated with proteinuria, diastolic BP, and renal dysfunction |
| Craici et al (2013)85 | 15 PE 15 GHTN 44 NL |
Late second trimester (median 27 weeks) | Podocyte culture | IF for podocin | Podocyturia present in 15/15 PE, absent in 15/15 GHTN, and absent in 44/44 NL Podocyturia in second trimester was more sensitive and specific for later PE than any combination of angiogenic factors |
| Garovic et al (2013)86 | 13 PE 6 PE/HELLP 4 NL |
< 24 hours before delivery | Trypsin digestion of the urinary sediment | LC-MS/MS | Podocin-specific tryptic peptide significantly higher in PE/HELLP compared to NL |
BP, blood pressure; GHTN, gestational hypertension; HTN, hypertension; IF, immunofluorescence; NL, normal pregnancy; NP, not pregnant; PE, pre-eclampsia; VEGF, vascular endothelial growth factor; HELLP, hemolysis, elevated liver enzymes, low platelet count; LC-MS/MS, liquid chromatography coupled with tandem mass spectrometry.