ABSTRACT
PURPOSE: Can certain characteristics identify as solvable some undiagnosed patients who seek extensive evaluation and thorough record review, such as by the Undiagnosed Diseases Network (UDN)? METHODS: The UDN is a national research resource to solve medical mysteries through team science. Applicants provide informed consent to access to their medical records. After review, expert panels assess if applicants meet inclusion and exclusion criteria to select participants. When not accepting applicants, UDN experts may offer suggestions for diagnostic efforts. Using minimal information from initial applications, we compare features in applicants who are not accepted with those who are accepted and either solved or still not solved by the UDN. The diagnostic suggestions offered to nonaccepted applicants and their clinicians were tallied. RESULTS: Nonaccepted applicants were more often female, older at first symptoms and application, and longer in review compared with accepted applicants. The accepted and successfully diagnosed applicants were younger, shorter in review time, more often non-White, of Hispanic ethnicity, and presenting with nervous system features. Half of nonaccepted applicants were given suggestions for further local diagnostic evaluation. A few seemed to have 2 major diagnoses or a provocative environmental exposure history. CONCLUSION: Comprehensive UDN record review generates possibly helpful advice.