The National Institutes of Health announced a new online portal for individuals who are facing an unidentified illness that has been difficult to diagnose. Officials said they hope the new resource helps provide answers for patients, and clinicians, confronted with rare or hard-to-diagnose diseases.

The portal is called the UDN Gateway, part of the NIH’s Undiagnosed Diseases Network. NIH officials say the online resource supports the UDN’s mission of diagnosing patients who suffer from conditions that even skilled physicians have been unable to diagnose despite extensive clinical investigation. These diseases are difficult for doctors to diagnose because they are rarely seen, have not previously been described or are unrecognized forms of more common diseases.

The portal provides an online application that individuals can complete to be considered for NIH clinicians and researchers to review the case and seek a diagnosis.

The UDN grew out of the Undiagnosed Diseases Program at the NIH Clinical Center in Bethesda, Md. Since its 2008 launch, the UDP has reviewed more than 3,100 applications from patients around the world. More than 800 patients have been enrolled for a one-week evaluation. While approximately 25 percent of those have received some level of clinical, molecular or biochemical diagnosis, many patients remain undiagnosed.

NIH officials said the program not only has the potential to offer answers to patients suffering a mystery illness, it also provides opportunities for greater awareness, understanding and research into rare diseases.