[Transient renal failure in a newborn due angiotensin receptor II antagonist use during pregnancy: report of a case].

Fetal renal structure and function can be altered by medications prescribed to pregnant women. We report a chronic hypertensive pregnant woman treated with losartan before and throughout pregnancy. At 30 weeks the patient was referred to our Fetal Medicine Unit due to absent amniotic fluid with normal uterine artery Doppler and fetal growth. During her hospitalization a new scan was performed showing that both fetal kidneys were enlarged and slightly hyperechogenic and placental and fetal artery Doppler showed signs of hypovolemia or increased resistance to feto-placental blood flow. Ductus venosous was normal. The fetus was delivered after three days by caesarean section at 30+4 weeks of gestation due to abnormal fetal heart rate tracing. Following delivery, the preterm newborn was treated for a transient renal failure characterized by anuria-oliguria and high plasma creatinine levels (from 3.8 mg/dL at day 5 to 0.8 mg/dL at 16 days). At 30 days of age, ultrasound showed kidneys of normal form and size. The adverse effects of Angiotensin II receptor antagonists in fetal nephrogenesis and function are discussed.