Who’s Eligible and How to Apply

Who’s eligible to participate in the Undiagnosed Disease Program

The Undiagnosed Disease Program at CHOP is meant to be a resource for families who have been unsuccessful in finding a diagnosis for their child through other avenues. To be considered for the program your child needs to:

  • Have a condition that remains undiagnosed despite thorough evaluation by a healthcare provider.
  • Have at least one objective finding (meaning they have a verifiable laboratory, imaging, or physical exam with an indication of a disease or injury, such as a heart defect or an abnormal thyroid level)
  • Agree to enroll in a research study that includes providing access to medical information and biological samples (such as a blood sample) to allow for thorough diagnostic evaluation

How patients and families apply

Before applying to the Undiagnosed Disease Program (UDP), we recommend that parents/guardians contact our office at 267-425-3949 or via email at UDNCHOP@chop.edu. We can determine if your child would be eligible. If they are, we’ll then direct you to complete the application paperwork.

We will request this information at the time of application:

  • Your contact and demographic information
  • Relevant healthcare provider(s) information (name, address, phone, fax, email)
  • Brief medical history, along with results of previous evaluations and tests

In order to confirm the program is a good fit for your child, it is best to have a healthcare provider write a letter recommending your child’s participation. If possible, the letter should include:

  • A summary of your child's medical problems, along with dates when symptoms were first noticed
  • A history of your child's evaluations, tests, treatments and/or medications, along with any previous diagnoses
  • A family medical history, as well as your child's prenatal and birth history
  • A list of any current medications your child is taking
  • The healthcare providers' diagnostic impressions of your child and their symptoms

Is CHOP still associated with the Undiagnosed Diseases Network (UDN)?

The UDN is a research program funded by the National Institutes of Health Common Fund. The UDN is made up of clinical and research centers across the United States working to improve diagnosis and care of patients with undiagnosed diseases. CHOP continues to partner with the NIH as a site for UDN clinical studies. Some patients seen in the CHOP UDP will also be asked if they would like to enroll in the UDN.

For families invited to enroll in the NIH Undiagnosed Diseases Network

A recommendation letter from a physician is required for applying to the UDN. Once you have the recommendation letter, you can apply online at the UDN Gateway and attach the letter. During the application process, you may request that your child's case be assigned to a specific geographic area or participating hospital, but there is no guarantee you will be assigned to that site.

Please note: Only a small percentage of applications will be accepted into the UDN study. However, even if your child is not accepted, you may still receive useful feedback from the study's clinical team with recommendations about your child's medical condition and suggestions about how best to move forward.

If your child is accepted into the UDN study, you will be assigned a study location partner and will work with staff there to determine possible dates for a 2- to 5- day visit to the clinical site for your child's study-specific medical and research evaluation.

CHOP’s Undiagnosed Disease Program is different in that it’s able to accept more applications.

Read frequently asked questions about the UDN.

For physicians whose patients are applying to the NIH Undiagnosed Diseases Network

In order to apply for your patient, you will first need their approval. Once they confirm their interest, reference the UDN's information for providers document and an example of a recommendation letter. Please request that the patient completes their initial application. 

Not eligible for CHOP’s Undiagnosed Disease Program?

If your child isn’t eligible for the UDP, there are other options for care at CHOP:

Roberts Individualized Medical Genetics Center (RIMGC)
Mitochondrial Medicine
Conditions Treated at CHOP
Current Research Trials


Next Steps