Abstract 158

Background: Human cystatin C is a basic low molecular mass protein (M=13,359) recently proposed as a very sensitive marker of changes in glomerular filtration rate. Cistatyn C is freely filtered by the glomerulus and almost completely reabsorbed and catabolized by proximal tubular cells.

Aim: In order to study its pathophysiology we measured serum cistatyn C, creatinine, and urea, in a group of pregnant women immediately before labour and in their newborns at birth, on day 3 and day 5 respectively.

Patients and methods: 63 healthy pregnant women, 19-40 years old, and their newborns were enrolled. In the newborns (38 males, 25 females) the 1-min. Apgar score ranged from 5 to 10, and the 5-min from 7 to 10. Cistatyn C was determined using the cistatyn C PET kit (Dako, Milan Italy). Serum creatinine and urea was measured using the Ektachem enzymatic essay(Ortho Clinical Diagnostics, Milan, Italy).

Results: In the pregnant women serum cistatyn C was 1.50± 0.37mg/L, ranging from 0.69 to 2.30 mg/L. Serum creatinine at birth was 57.6±10.9 µmol/L, and serum urea was 3.08±0.75 mmol/L. In the newborns, serum cistatyn C at birth was 2.28 ± 0.50 mg/L, ranging from 1.17 to 4.84 mg/L. Subsequently cistatyn C values significantly decreased over the first 5 days of life; serum creatinine at birth was 78 ± 14.6 µmol/L. ranging from 43 to 106µmol/L. By using analysis of the variance (ANOVA) we found a statistically significant difference between maternal and neonatal creatinine(p< 0.001). However, no correlation was demonstrated by a simple linear regression between maternal and neonatal cistatyn C (r=0.11). while maternal and neonatal creatinine significantly correlated (r=0.52).

Conclusion: Our preliminary findings suggest that cistatyn C does not cross the placental barrier, but more studies are required in this field.