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NIH Undiagnosed Diseases Program



The NIH Undiagnosed Diseases Program (UDP) is a National Institutes of Health (NIH) clinical research initiative launched in May 2008 by the National Human Genome Research Institute (NHGRI), the NIH Clinical Center and the NIH Office of Rare Diseases Research.

Individuals whose conditions have eluded medical diagnoses may apply to become UDP participants and, if invited, are admitted to the NIH Clinical Center in Bethesda, Md. Each patient undergoes a week of diagnostic tests and expert consultations provided for free at one of the world's largest medical research institutes.

The patient is examined by a multidisciplinary medical team with a deep base of knowledge about rare and common diseases. The team, drawn from various NIH institutes and centers, studies a patient's clinical and laboratory results for diagnostic clues while the patient is in the Clinical Center and in the weeks and months following their visit.

Ultimately, the UDP offers patients the hope of a diagnosis and the possibility of therapeutic strategies. In return, patients provide UDP researchers the opportunity to gain new insights about genetic and biochemical mechanisms of disease and insights into normal cell biology, biochemistry and physiology. So far, UDP researchers have encountered patients with uncommon presentations of known disorders, multi-systemic complex disorders and new disorders that have never been diagnosed.

UDP clinical researchers are using advances in DNA sequencing to detect defects in genes that point to known disorders. These tools offer the potential for discoveries about the role of molecular and biochemical events that can cause disease and, eventually, the development of diagnostic and therapeutic approaches for rare and common diseases.

The caseload of the UDP is steadily growing, with more than 100 pediatric and adult patients added each year. The volume of applications from patients across the country, and abroad, has exceeded expectations, reflecting that the UDP fills an unmet need for undiagnosed patients.

UDP facts (May 2008 through May 2014)
  • Inquiries: 9,300.
  • Applications: 3,100.
  • Acceptances: 750.
  • Patients seen or scheduled: 700.
  • Approximate annual patient visit rate: 130.
  • Approximate distribution of patients seen: 40 percent pediatric cases and 60 percent adult cases.
  • Percentage of cases resolved with a either a clinical, molecular or biochemical diagnosis: a range between 25 and 50
  • Number of cases closed with no diagnosis: approximately 25 percent.
  • Number of cases pending diagnosis with strong leads: approximately 60.
  • Range in time to reach a diagnosis: from one week to four years.
  • Types of DNA analyses conducted: million-SNP (single nucleotide polymorphism) array scans performed for approximately 1,600 individuals (patients and family members); whole-exome sequencing analyses performed for approximately 900 individuals.

The NIH Common Fund awarded $5.6 million for FY14 to the NIH Undiagnosed Diseases Program, a clinical site of the Undiagnosed Diseases Network.

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Last Updated: September 2, 2015

See Also:

Undiagnosed Diseases Network

On Other Sites:

Undiagnosed Diseases Network
At the NIH Common Fund