Current Environment:


Background: - Without an explanation for severe and sometimes life-threatening symptoms, patients and their families are left in a state of unknown. The NIH helped create a network of medical research centers, called the Undiagnosed Diseases Network (UDN), to provide care and answers for these individuals. Objectives: - To improve diagnosis and care for people with undiagnosed diseases. Eligibility: - People with undiagnosed diseases, and their relatives. Design: Participants will travel to one of the UDN medical centers for a 5-day clinical and research visit. As part of the visit, UDN healthcare providers may ask participants to have: Clinically indicated tests and procedures performed including: A physical exam Blood and urine tests A review of health and family history X-rays and body scans Surveys Photographs of the face and body A special diet to see if the body can handle the food without having a reaction, like vomiting Video or voice recordings Other tests and procedures to help reach a diagnosis Research tests and procedures performed including: A skin biopsy. For this, a small piece of skin will be taken. Surveys Other tests and procedures for research that may not be related to a diagnosis or treatment. Most participants will be asked to give samples for genetic testing. Participants may be contacted after their visit to discuss test results. They may also be contacted in the future for interviews and surveys. Relatives of participants may be asked to give samples for genetic testing. They may be asked to have parts of their visit recorded and to have additional tests. They may also be contacted in the future for interviews and surveys. Clinical and research information collected will be stored in a database. Information and samples collected will be shared with others for research purposes.


Genetic Disease

Recruitment Status


Detailed Description

Without an explanation for severe and sometimes life-threatening symptoms, patients and their families are left in a state of unknown. Many individuals find themselves being passed from physician to physician, undergoing countless and often repetitive tests in the hopes of finding answers and insight about what the future may hold. This long and arduous journey to find a diagnosis does not end for many patients- the Office of Rare Diseases Research (ORDR) notes that 6% of individuals seeking their assistance have an undiagnosed disorder. In 2008, the National Institutes of Health (NIH) Undiagnosed Diseases Program (UDP) was established with the goal of providing care and answers for these individuals with mysterious conditions who have long eluded diagnosis. The NIH UDP is a joint venture of the NIH ORDR, the National Human Genome Research Institute Intramural Research Program (NHGRI-IRP), and the NIH Clinical Research Center (CRC). The goals of the NIH UDP are to: (1) provide answers for patients with undiagnosed diseases; (2) generate new knowledge about disease mechanisms; (3) assess the application of new approaches to phenotyping and the use of genomic technologies; and (4) identify potential therapeutic targets, if possible. Prior to formation of the Undiagnosed Diseases Network (UDN), the UDP had evaluated 3300 medical records, admitted 750 individuals with rare and undiagnosed conditions to the NIH Clinical Center, and identified more than 70 rare disease diagnoses and several new conditions. The success of the NIH UDP prompted the NIH Common Fund to support the establishment of a network of medical research centers, the UDN, for fiscal years 2013-2022. The clinical sites perform extensive phenotyping, genetic analyses, and functional studies of potential disease-causing variants. The testing performed on patients involves medically indicated studies intended to help reach a diagnosis, as well as research investigations that include a skin biopsy, blood draws, and DNA analysis. In addition, the UDN is furthering the goals of the UDP by permitting the sharing of personally identifiable phenotypic and genotypic information within the network. By sharing participant information and encouraging collaboration, the UDN hopes to improve the understanding of rare conditions and advance the diagnostic process and care for individuals with undiagnosed diseases.

Eligibility Criteria


Ideal applicants to the UDN include individuals with:

One or more objective findings pertinent to the phenotype for which a UDN application was submitted.
No diagnosis despite evaluation by at least two specialists who assessed the patient for the objective finding(s).
Agreement for the storage and sharing of information and biomaterials, in an identified fashion amongst the UDN centers, and in a de-identified fashion to research sites beyond the network.
Applicants unable to consent can be enrolled.


-Applicants who are unlikely to be accepted include individuals with:

Reported symptoms with no relevant objective findings.
A diagnosis explaining objective findings.
A diagnosis suggested on record review.
Unwillingness to share data.



Min Age

1 Month

Max Age

100 Years

Download Date

February 9, 2023

Principal Investigator


Primary Contact Information

Paul Mazur

(844) 746-4836

For more information on this trial, visit


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