Studies of States With Resistance to Vitamin D and Parathyroid Hormone

Patients with confirmed or suspected states with resistance to vitamin D or parathyroid hormone (PTH) will be admitted for diagnosis, treatment review with suggestions for modifications to the current or new treatment and for inclusion in other protocols. These states include hypocalcemia, rickets, osteomalacia, pseudohypoparathyroidism. Resistance to a factor is manifested by deficient bioeffect despite high levels of the factor in blood. Patients will be tested with multiple indices of mineral metabolism to establish the diagnosis and examine the spectrum of the underlying disorder. The principal therapies will be combinations of calcium, phosphate, and a vitamin D analog. Selected patients will have localization and surgery to remove a tumor that causes renal wasting of phosphate. Patients will also be considered for entry into other research protocols.

Study Overview

Detailed Description

Patients with confirmed or suspected states with resistance to vitamin D or parathyroid hormone (PTH) will be admitted for diagnosis, treatment review with suggestions for modifications to the current or new treatment and for inclusion in other protocols. These states include hypocalcemia, rickets, osteomalacia, pseudohypoparathyroidism. Resistance to a factor is manifested by deficient bioeffect despite high levels of the factor in blood. Patients will be tested with multiple indices of mineral metabolism to establish the diagnosis and examine the spectrum of the underlying disorder. The principal therapies will be combinations of calcium, phosphate, and a vitamin D analog. Selected patients will have localization and surgery to remove a tumor that causes renal wasting of phosphate. Patients will also be considered for entry into other research protocols.

Study Type

Observational

Enrollment (Actual)

70

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Maryland
      • Bethesda, Maryland, United States, 20892
        • National Institutes of Health Clinical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

2 months to 100 years (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Patients with confirmed or suspected states with resistance to vitamin D or parathyroid hormone (PTH)

Description

  • INCLUSION CRITERIA:

Patients, from 2 months to 100 years of age, of either sex M or F, with vitamin D resistance, rickets, osteomalacia, pseudohypoparathyroidism, pseudo-pseudohypoparathyroidism, or suspicion of these or related disorders based upon the appropriateness of their problem to ongoing investigations.

Current investigations are focused principally upon the inclusion of subjects with, or suspected of having, hypocalcemia likely due to a resistance to parathyroid hormone, including subjects who have a diagnosis, or likely diagnosis, of pseudohypoparathyroidism or pseudopseudohypoparathyroidism.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Cohort
  • Time Perspectives: Prospective

Cohorts and Interventions

Group / Cohort
Study Cohort
Patients of any age or sex with vitamin D resistance, rickets, osteomalacia, pseudohypoparathyroidism, pseudo- pseudohypoparathyroidism, or suspicion of these or related disorders

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
This study will provide information about problems relating to calcium in the blood, urine, and bones
Time Frame: take one to two weeks
This is a natural history protocol, directed at diagnosing and managing the general clinical features in these patients. In addition the full clinical expression of certain rare disorders (target resistance to 1,25(OH)2D, pseudohypoparathyroidism, and pseudo- pseudohypoparathyroidism) will be characterized further. Some of these patients or their relatives will be entered into additional protocols, where appropriate for example, protocols to characterize the molecular causes of these disorders.
take one to two weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Lee S Weinstein, M.D., National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 12, 1997

Primary Completion (Actual)

December 12, 2022

Study Completion (Actual)

December 12, 2022

Study Registration Dates

First Submitted

November 3, 1999

First Submitted That Met QC Criteria

November 3, 1999

First Posted (Estimate)

November 4, 1999

Study Record Updates

Last Update Posted (Actual)

January 20, 2023

Last Update Submitted That Met QC Criteria

January 19, 2023

Last Verified

January 1, 2023

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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