6403: Screening for Dent Disease Mutations in Patients with Proteinuria

Status: Recruiting



Dent Disease is a rare hereditary disorder that can cause kidney stones, nephrocalcinosis (calcium deposits in the kidney tissue), and end stage renal failure (kidney failure).

In this study, patients that might have Dent disease will be given a blood test to look for genetic mutations that cause the disease. Participants may also be asked to provide a urine sample to test for proteinuria (too much protein in the urine).

Patients with Dent disease can have a variety of symptoms and lab test results. This can make it difficult to make a Dent disease diagnosis. The difficulty to diagnose Dent disease can mean that patients are likely under-diagnosed. Some patients have typical symptoms such as kidney stones, nephrocalcinosis, hypercalciuria (too much calcium in the urine) low molecular weight proteinuria (proteins of low molecular weight in the urine). Some patients might only have proteinuria. Since proteinuria is seen with many kidney diseases, the diagnosis of Dent disease may not be made from this symptom alone. This study will help physicians better understand Dent disease.

The research questions are:

  1. How widespread is Dent disease and the genetic mutations that cause the disease (CLCN5 and OCRL-1)?
  2. How common is Dent disease in first-degree relatives (such as parents, children or siblings)?
  3. What are the signs of the disease in females who have one copy of an affected Dent gene?
  4. How many patients diagnosed with other kidney diseases (FSGS, Diabetic nephropathy, nephrotic syndrome, reflux nephropathy, hypertensive nephrosclerosis, FSGS, Medullary Sponge Kidney) might also have Dent disease gene mutations?

About this Study

The purpose of this study is to:

  • Test patients who are suspected to have Dent Disease (low molecular weight proteins in their urine and/or with symptoms of nephrocalcinosis, kidney stones or hypercalciuria).
  • Test first-degree relatives of patients with confirmed genetic mutations.

There will be a total of 602 participants in this study. The plan is to have 300 people take part in this study at Mayo Clinic. Subjects will only be in the study for the time it takes for one blood draw or a possible random urine collection.

Subjects that agree to be in the study will be asked to:

  • Provide a blood sample for DNA (genetic) testing (All participants)
  • Provide a urine sample (Not every participant will be asked to provide this)

Blood samples. Genetic material (DNA) is found in your cells. It is specific to you. Genes control traits we inherit from our parents, such as hair and eye color. The amount of blood drawn for the study is about two teaspoons (10 mL) for adult and pediatric participants. The blood will be tested for the Dent Disease genes (CLCN5 and OCRL-1)

Urine samples. If you will be providing a 24-hour urine sample as part of your routine, standard of care, a small portion of that can be taken from that collection. If you have given a urine sample previously, to be used for future research, you will not need to provide another sample.

Targeted Enrollment

Who is eligible to participate?

  • Have a suspected diagnosis of Dent Disease (elevated urine tests for retinol binding protein or α 1 microglobulin) and /or nephrocalcinosis (calcium deposits in the kidney tissue), kidney stones or hypercalciuria (high levels of urine calcium)
  • Be a first degree relative of a patients with confirmed Dent disease genetic mutations
  • Have proteinuria (excess protein in the urine ) from:
    • Hypertensive nephrosclerosis (hardening of the kidney associated with high blood pressure)
    • FSGS (Focal segmental glomerulosclerosis) scar tissue that forms in parts of the kidney called glomeruli
    • Medullary sponge kidney (defect of the kidneys where the kidneys fill with pools of urine)
    • Other unexplained cause of proteinuria or nephrocalcinosis diagnosed at Mayo Clinic, Rochester

You are not eligible to participate if:

  • You have decreased kidney function (a GFR <15 ml/min/1.73 m2 )

How to participate

In order to participate in a study, you must personally contact the study coordinator of any of the participating institutions by phone or by e-mail. Please use the information below to inquire about participation.

United States


Mayo Clinic College of Medicine, Rochester
Contact: Julie Olson, Barb Seide and Alicia Meek
Phone: 507-284-1004
Phone: 800-270-4637
E-mail: rarekidneystones@mayo.edu