#2095 Genetic kidney disease in pregnancy – experience of tertiary referral hospital

Abstract Background and Aims Genetic kidney diseases (GKD) are rarely seen in pregnancy and some diagnosis will only be made during gestation, due to a high proportion of chronic kidney diseases (CKD) of unknown etiology and recent advances in genetic testing. Genetic counseling and, when possible, preimplantation genetic testing (PGT) should be offered pre-pregnancy to this specific CKD population. Method Retrospective analysis of maternal, obstetric and perinatal outcomes of pregnant women with GKD surveilled at Hospital Santa Maria, at the nephro-obstetric clinic from 2011 to 2023. Results We evaluated 34 pregnancies in 28 women, mean maternal age 30±6 years-old 21-37, 89% Caucasian. Molecular genetic testing was performed pre-pregnancy, during and post-pregnancy in 12/19, 2/19 and 5/19 patients, respectively. At baseline, mean serum creatinine (SCr) and proteinuria (Pr) was 1.0±0.9 mg/dL and 222±516 mg/g, with CKD stage 1/2/3/4/5 in 27/2/2/1/2 gestations and chronic hypertension (HTN) in 11/34 pregnancies. Only 1/28 patients performed PGT, while 1/28 patient declined it. De novo or increased Pr occurred in 10/34 gestations and de novo or worsening HTN in 5/34 gestations. Deterioration of renal function occurred in one patient (CKD3) without recovery and one patient (CKD5) induced dialysis 4 months post-pregnancy. Nephrotic Pr developed in 4/34 gestations. One patient (FSGS APOL1) was treated with tacrolimus and low dose steroids. The patient with TSC re-started sirolimus on week 22 to treat severe fetal ventricular rhabdomyoma. Miscarriage occurred in 2 pregnancies. The C section rate was 21,8%. There were 7 preterm deliveries of which 3 before 32 weeks of pregnancy, mainly due to severe preeclampsia. Mean gestational age at delivery was 37,6 ± 4 weeks (26-41), mean birth weight 2756 ± 831 g (560-3835). Eight newborns were admitted to neonatal ICU due prematurity, fetal TSC, and feeding difficulties. Pulmonary hemorrhage and sepsis caused the death of 2 newborns. We found 1 maternal death, due to rupture of a cerebral aneurism 1 month postpartum (PKD patient). Conclusion Our cohort was very heterogenous regarding CKD etiologies, but generally with good kidney function, which allowed overall good obstetric outcomes. Still, maternal, obstetric and fetal complications, namely HTN, Pr, PE and prematurity had an increased incidence compared to pregnancy in healthy patients. This particular population should be approached by an experienced multidisciplinary team in CKD pregnancy care to optimize outcome.