Neonatal nephrotic presentation of a child with heterozygous NPHS1 mutation

Congenital nephrotic syndrome of the Finnish type, due to homozygous mutation of NPHS1, is the most common form of congenital nephrotic syndrome. Angiotensin converting enzyme (ACE) and prostaglandin synthesis inhibition along with supportive albumin infusion therapy, with or without unilateral nephrectomy, has allowed management of the disease without dialysis until transplantation in some cases of congenital nephrotic syndrome. Reported here is a case of heterozygous NPHS1 mutation, with normal NPHS2 gene structure, presenting during prenatal screening and developing nephrotic syndrome within days of birth. The patient has responded well to very low doses of ACE inhibitors and indomethacin alone. This case illustrates the importance of an initial trial of conservative medical therapy in milder presentations of the congenital nephrotic syndrome, especially given the current limitations of diagnostic testing and our inadequate knowledge of the complete spectrum of disorders of podocyte proteins.