Abstract
Congenital nephrotic syndrome (CNS) is a severe renal disorder in newborns, characterized
by complications such as albuminuria, hypoalbuminemia, and hypercoagulability. While
CNS is known to predispose patients to thrombosis over time, to our knowledge, cerebrovascular
complications such as cerebral sinovenous thrombosis (CSVT) within the first week
after birth have rarely been reported before in neonates with confirmed CNS. We present
here an infant, born by normal vaginal delivery, which was complicated by the retention
of a large placenta. She was first admitted on day 3 with perioral cyanosis and polycythemia.
She developed apneas that were later confirmed with amplitude integrated EEG to be
seizures and was found to have multiple thrombotic complications, including extensive
CSVT and bilateral thalamic hemorrhages. Serum albumin level was very low, with high
urinary levels suspicious for Finnish-type CNS, which was confirmed by NPHS1 pathogenic variants p.Cys623Phe and p.Asn870Profs*36. Despite partial exchange transfusions
and anticoagulation therapy, the infant developed severe cerebral abnormalities. This
case underscores the importance of considering CNS in neonates with a large placenta,
severe polycythemia, proteinuria, and hypoalbuminemia, as they may be at risk of developing
CSVT.
Keywords
congenital nephrotic syndrome - cerebral sinovenous thrombosis - thalamic hemorrhage
