Parathyroid Hormone (PTH) Homeostasis in Bartter Syndrome

The recruitment status of this study is unknown because the information has not been verified recently.
Verified June 2012 by Soroka University Medical Center.
Recruitment status was  Not yet recruiting
Sponsor:
Collaborator:
Ben-Gurion University of the Negev
Information provided by (Responsible Party):
Daniel Landau MD, Soroka University Medical Center
ClinicalTrials.gov Identifier:
NCT01021280
First received: November 25, 2009
Last updated: June 13, 2012
Last verified: June 2012
  Purpose

Parathyroid hormone (PTH) gland calcium sensing receptor (CASR) regulates PTH secretion. CASR is also expressed in nephron thick ascending limb (TAL). Bartter syndrome (BS), a normotensive hypokalemic tubulopathy, may be due to mutations in different TAL channels, including the potassium channel ROMK. Mutations in CASR may also cause BS through its effects on ROMK function. However, it is unknown whether ROMK mutations exert any effects on CASR function and PTH physiology. Preliminary data from our center shows that PTH levels were specifically elevated in type II (where ROMK is mutated) and not in type IV (where another gene, Barttin is defective) BS, without a common explanation. We assume that the mutation in ROMK may cause a dysregulation of PTH secretion via possible interaction with CASR.

The purpose of this study is: to investigate the PT-gland function and regulation in BS.

Methods: Patients with BS type II and IV and normal controls will undergo a standard protocol of controlled ionic hypo- and hypercalcemia, during which PTH secretion, phosphate balance and calcium excretion will be followed. Calcium Vs PTH response curves will be generated and compared.

Expected impact and benefit: the results of this study will help understand the mechanisms of PTH regulation beyond CASR.


Condition
Hypocalcemia
Hypercalcemia

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Prospective
Official Title: Case-control Study of the PTH Homeostasis in Adolescents and Young Adults With Bartter Syndrome

Resource links provided by NLM:


Further study details as provided by Soroka University Medical Center:

Biospecimen Retention:   Samples Without DNA

Serum and urine will be later analyzed for FGF-23 and other key molecules in PTH homeostasis.


Estimated Enrollment: 15
Study Start Date: January 2013
Estimated Study Completion Date: June 2014
Estimated Primary Completion Date: December 2013 (Final data collection date for primary outcome measure)
Groups/Cohorts
Type II BS
Adolescents and young adults with type II Bartter syndrome
Type IV BS
Adolescents and adults with type IV Bartter syndrome
Controls
Age and sex- matched controls

  Show Detailed Description

  Eligibility

Ages Eligible for Study:   14 Years to 35 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

Adolescent and young adult patients with Bartter syndrome and age- and sex- matched controls.

Criteria

Inclusion Criteria:

  • Bartter syndrome
  • Normal Vitamin D status

Exclusion Criteria:

  • Age < 14 yrs
  Contacts and Locations
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, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01021280

Locations
Israel
Soroka University medical Center Not yet recruiting
Beer Sheva, Israel, 84101
Contact: Daniel Landau, MD    972-8-6400546    ldaniel@bgu.ac.il   
Contact: Ruth Schreiber, MD    972-8-6400546    ruthalon@rogers.com   
Principal Investigator: Daniel Landau, MD         
Sub-Investigator: Ruth Schreiber, MD         
Sponsors and Collaborators
Soroka University Medical Center
Ben-Gurion University of the Negev
  More Information

No publications provided

Responsible Party: Daniel Landau MD, Head, Pediatrics Department A and Pediatric Nephrology Service, Soroka University Medical Center
ClinicalTrials.gov Identifier: NCT01021280     History of Changes
Other Study ID Numbers: Sor492809ctil
Study First Received: November 25, 2009
Last Updated: June 13, 2012
Health Authority: Israel: Ministry of Health

Keywords provided by Soroka University Medical Center:
Bartter syndrome,
parathyroid hormone,
calcium sensing receptor,
ROMK channel
Barttin gene
PTH response to hypo- and hypercalcemia

Additional relevant MeSH terms:
Hypercalcemia
Bartter Syndrome
Hypocalcemia
Renal Tubular Transport, Inborn Errors
Kidney Diseases
Urologic Diseases
Hyperaldosteronism
Adrenocortical Hyperfunction
Adrenal Gland Diseases
Endocrine System Diseases
Calcium Metabolism Disorders
Metabolic Diseases
Water-Electrolyte Imbalance

ClinicalTrials.gov processed this record on August 21, 2014