© 2018, GENASSIST, Inc.     

By Keith S. Wexler, MBA, Maternal Fetal Medicine, Prenatal Diagnosis and Biotech/Life Sciences Consultant, GENASSIST, Inc.

Paul Wexler, M.D., F.A.C.O.G., Medical Director, GENASSIST, Inc.

Clinical Professor, Department of OB/GYN, University of Colorado Health Sciences Center

Clinical Professor, Division of Genetics/Dept. of Pediatrics, Univ. of Colorado/The Children’s Hospital

Background:  A patient seen by her healthcare provider for her 20 week Level II ultrasound was found to have bilateral hydronephrosis (accumulating fluid in the kidneys and or collecting systems for the kidneys) of 5 mm.  The healthcare provider referred her to us for a 2nd opinion and a diagnosis of possible Polycystic Kidneys was made by Dr. Wexler.

Patient was referred to Maternal Fetal Medicine for confirmation of kidney and liver cysts.

Polycystic Kidneys and/or Polycystic Kidney Disease (PKD) is inherited in an autosomal dominant (50% risk to first degree relatives) or autosomal recessive manner (25% if both parents are gene carriers).

One of the characteristics of a disease caused by inheritance of a single deleterious gene (autosomal dominant inheritance) is variable severity.  This means that any or all children who inherit the deleterious gene (50% of children) could have milder or more severe problems related to their kidney function. 

Polycystic Kidney Disease has an incidence of approximately1:400 to 1:1000.

Polycystic Kidney Disease  may be acquired.

Most case of PKD are due to one or more mutations in the PKD1 gene on the short arm on chromosome #16 (16p13.3) or the PKD2 gene on the long arm of chromosome #4 (4q21-13). 

If the mutation is identified in the patient then Preimplantation Genetic Diagnosis becomes a possibility.

PKD causes multiple cysts to form in the kidneys and occasionally the liver and rarely the pancreas. Heart valve problems, abdominal wall hernias and intracerebral aneurysms can occur. 

The kidney cysts diminish kidney function eventually resulting in kidney failure.

The condition may be asymptomatic early in the course of the disease but can cause abdominal or back pain, blood in the urine, kidney stones, kidney infection, fatigue, joint pain and skin or nail abnormalities.

At least 400 mutations have been identified in the PKD1 gene responsible for approximately 85% of cases of Polycystic Kidney Disease (Type I) and over 40 mutations have been identified in the PKD2 gene responsible for approximately 15% of cases of Polycystic Kidney Disease (Type II)

Rarely, mutations in a third gene – PKD3 also can result in autosomal dominant PKD.

PKD can affect both the liver and kidneys and can result in serious renal problems either shortening the individual’s lifespan or resulting in kidney transplantation.