Assessment of Serum Cystatin C as a Marker of Kidney Function in Children

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00300066
Recruitment Status : Completed
First Posted : March 8, 2006
Last Update Posted : May 28, 2010
Aarhus University Hospital
Information provided by:
Aalborg Universitetshospital

Brief Summary:

The purpose of this study is to assess serum cystatin C as a marker of kidney function (glomerular filtration rate, GFR) in children aged 2-14. The individual production rate and possible extra renal elimination of cystatin C based on body composition data is included to develop new algorithms to estimate GFR.

Furthermore, day-to-day variation on serum cystatin C is investigated.

Condition or disease
Kidney Disease

Detailed Description:

Today, children's kidney function (glomerular filtration rate, GFR) can be monitored by two methods:

  1. indirectly by serum creatinine, or
  2. directly by injection of a radioactive substance followed by several blood samples.

The first method is inaccurate with many drawbacks, whereas the latter is precise but time-consuming and unpleasant for the child. Therefore, there is a need for a new method for investigating GFR in children.

Serum cystatin C is a small protein that is produced with a constant rate in all nucleated cells in the body. It meets many of the characteristics of an ideal marker of GFR because of the way it is excreted in the kidneys. However, earlier studies have not proven serum cystatin C to be convincingly better than serum creatinine. Why? If there is considerable extra renal elimination, serum cystatin C alone isn't enough to estimate GFR. Therefore, the individual production rate and possible extra renal elimination of cystatin C are included in this study. To assess these factors, the children are submitted to bioelectrical impedance spectroscopy (BIS) to estimate their body composition, including body cell mass as cystatin C is produced in all nucleated cells. To validate the BIS data, dual energy x-ray absorptiometry (DEXA) will be conducted on 100 of the included children.

Based on serum cystatin C and the individual, age-corrected extra renal elimination rate of cystatin C, new algorithms to calculate GFR can be developed.

Furthermore, day-to-day variation in serum cystatin C and BIS data, which is expected to be low, is investigated in 100 of the included children.


  1. Day-to-day variation on serum cystatin C is low.
  2. Serum cystatin C raises parallel to falling GFR with time, which means that serum cystatin C can be used to monitor changes in kidney function in each patient.
  3. Based on body composition, regression analysis and serum cystatin C values, GFR can be estimated in children aged 2-14.
  4. GFR calculated as stated above is a more precise measurement of kidney function and changes in kidney function than GFR estimated from serum creatinine.
  5. Data of body composition estimated by BIS do not deviate from data estimated by DEXA
  6. Day-to-day variation in data for body composition measured by BIS is low.

The project includes 200 children aged 2-14 who are referred for routine examination of GFR in two Departments of Nuclear Medicine.

Study Type : Observational
Estimated Enrollment : 200 participants
Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Prediction Equations for Glomerular Filtration Rate in Children Based on Serum Cystatin C and Body Cell Mass
Study Start Date : March 2006
Actual Primary Completion Date : December 2008
Actual Study Completion Date : December 2008

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   2 Years to 14 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Children aged 2-14 years referrede for GFR measurement

Inclusion Criteria:

  • Children aged 2-14 years referred for GFR measurement by 51-CrEDTA

Exclusion Criteria:

  • GFR measurement by capillary technique
  • Immune compromising treatment
  • Previous kidney transplant
  • Hypo- or hyperthyroidism
  • Increased C-reactive protein (CRP)
  • Rheumatoid arthritis
  • Ascites
  • Pacemaker (only exclusion for BIS and DEXA)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00300066

Department of Nuclear Medicine, University Hospital Aarhus, Skejby
Aarhus, Brendstrupgaardsvej 100, Denmark, 8200
Department of Clinical Physiology, University Hospital of Aarhus, Aalborg
Aalborg, Hobrovej 18-22, Denmark, 9000
Sponsors and Collaborators
Aalborg Universitetshospital
Aarhus University Hospital
Principal Investigator: Trine B Andersen, MD University Hospital of Aarhus

Responsible Party: Trine Borup Andersen, MD, Department of Nuclear Medicine Identifier: NCT00300066     History of Changes
Other Study ID Numbers: VN-20050065MCH
First Posted: March 8, 2006    Key Record Dates
Last Update Posted: May 28, 2010
Last Verified: May 2010

Keywords provided by Aalborg Universitetshospital:
Glomerular Filtration Rate
Serum Cystatin C
Body Composition
bioelectrical impedance spectroscopy

Additional relevant MeSH terms:
Kidney Diseases
Urologic Diseases
Cysteine Proteinase Inhibitors
Protease Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action