Congenital nephrosis, mesangial sclerosis, and distinct eye abnormalities with microcoria: an autosomal recessive syndrome.

We observed the occurrence of congenital nephrotic syndrome (CNS) and distinct ocular anomalies in two unrelated families. Eleven children from both families presented with a similar course of renal disease starting with nephrotic syndrome and renal failure prenatally or immediately after birth that resulted in death before the age of 2 months. Kidney histopathology showed diffuse mesangial sclerosis (DMS). Clinically obvious eye abnormalities were recognized in six of the eight patients in whom sufficient clinical data were available. Ocular anomalies included enlarged or large appearing corneae in some cases suggesting buphthalmos, and extremely narrow, nonreactive pupils (microcoria). Pathological examination of the eyes of two aborted fetuses revealed a more complex ocular maldevelopment including posterior lenticonus as well as anomalies of cornea and retina. On the basis of these observations and other cases in the literature, we delineate a previously unrecognized distinct entity characterized by congenital nephrotic syndrome, DMS, and eye abnormalities with microcoria as the leading clinical feature. Pedigrees of affected families with parental consanguinity support autosomal recessive inheritance. We propose that this syndrome should be designated microcoria-congenital nephrosis syndrome or Pierson syndrome. Possible overlap with Galloway-Mowat syndrome and relations to other oculo-renal syndromes are discussed.