Pregnancy complications and gestational proteinuria and serum creatinine dynamics in women with chronic glomerulonephritis and chronic tubulointerstitial kidney diseases

Introduction . Women with chronic kidney disease (CKD) have an increased incidence of pregnancy complications, but few comparative studies on features of pregnancy course during chronic glomerulonephritis (CGN) and chronic tubulointerstitial kidney disease (CTID) are available. Aim : comparison the frequency of pregnancy complications, proteinuria (PU) and serum creatinine dynamics in patients with CGN and CTID. Materials and Methods . We conducted an observational single-centre study enrolling 128 pregnant women with CGN (135 deliveries) and 138 with CTID (145 deliveries) by assessing the incidence of complications, diurnal PU, serum creatinine level starting from early gestation to delivery every 4–6 weeks. Results . Favourable pregnancy outcome was observed in 94.8 % of patients with CGN and in 95.7 % with CTID. The incidence of preeclampsia (PE), placental insufficiency, acute kidney injury, and preterm delivery showed no not inter-group differences, but arterial hypertension, PU > 1.0 g/day were more common in CGN, whereas in CTID – urinary tract infections. During pregnancy, PU increased in both groups, and only in CGN in patients with PE early pregnancy PU was significantly higher than in those without PE. Both groups showed similar serum creatinine dynamics: decrease starting from early pregnancy stages, stabilization in the middle of pregnancy followed by elevation from 28–30 weeks of gestational age until delivery. Conclusion . High PU level in early pregnancy may help to predict PE in CGN, but not in CTID. In patients with CKD, rise in PU along with serum creatinine increased up to baseline level in late pregnancy, are typically observed and without PE, fetal distress should not be considered as unambiguous indication for early delivery.