Pierson syndrome

Other Names: Microcoria - congenital nephrotic syndrome; Microcoria - congenital nephrosis

An autosomal recessive disorder caused by mutation(s) in the lamb2 gene, encoding laminin subunit beta-2. It is characterized by congenital nephrotic syndrome with diffuse mesangial sclerosis and distinct ocular abnormalities.

Pierson syndrome is a very rare condition that mainly affects the kidneys and eyes.

Cause

Pierson syndrome is caused by changes (mutations) in the LAMB2 gene.

Inheritance

Pierson syndrome is inherited in an autosomal recessive manner. This means that to be affected, a person must have a mutation in both copies of the responsible gene in each cell. Affected people inherit one mutated copy of the gene from each parent, who is referred to as a carrier. Carriers of an autosomal recessive condition typically do not have any signs or symptoms (they are unaffected). When 2 carriers of an autosomal recessive condition have children, each child has a:

• 25% (1 in 4) chance to be affected
• 50% (1 in 2) chance to be an unaffected carrier like each parent
• 25% chance to be unaffected and not be a carrier

Signs and symptoms

• The features and severity of Pierson syndrome can vary among affected people. Affected infants are usually born with serious and progressive kidney disease due to congenital nephrotic syndrome, although some do not have kidney failure until adulthood. Most require a renal transplant for end-stage kidney disease within the first decade of life.
• Ocular (eye) abnormalities are another common feature of Pierson syndrome. Most affected infants are born with abnormally small pupils (microcoria). Other ocular abnormalities may include cataracts, glaucoma, retinal detachments, and blindness.
• Those that survive past infancy typically have neurological disabilities and developmental delays. Many children with Pierson syndrome don't achieve normal milestones such as sitting, standing, and talking.

Diagnosis

Yes. The Genetic Testing Registry (GTR) provides information about the genetic tests available for Pierson syndrome. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional. According to the GTR, genetic testing for Pierson syndrome may be available for diagnosis in a person suspected of having the condition, carrier testing, and prenatal testing.

Treatment

Glaucoma, cataracts and retinal detachments require their usual treatment. Lifelong monitoring is required, but affected children may not live beyond the first decade of life.

Prognosis

Pierson syndrome carries a serious prognosis because of the eventual failure of the kidneys. Most affected infants progress towards renal failure within the first days or months of life. A kidney transplant may restore kidney function.

NIH genetic and rare disease info

• NIH info on Pierson syndrome

Pierson syndrome is a rare disease.