Pierson syndrome: a novel cause of congenital nephrotic syndrome.

In this report, we describe a newborn infant who presented with congenital nephrotic syndrome and renal insufficiency, as well as bilateral microcoria. This constellation of findings is a hallmark of Pierson syndrome, a newly recognized genetic disorder that is caused by a deficiency of β2 laminin in the basement membrane. Our patient demonstrated classic histopathologic findings of Pierson syndrome on renal biopsy, including absence of β2 laminin on immunofluorescent staining, and genetic testing confirmed the diagnosis. We conclude that Pierson syndrome should be included in the differential diagnosis for congenital nephrotic syndrome, especially in patients with ocular abnormalities.