Undiagnosed PKU Can Exist Everywhere: Results From an International Survey

NBS programs for Phenylketonuria (PKU; OMIM 261600) have been successfully implemented in many countries for over 50 years, however, globally there are still countries without NBS or with an ineffective NBS program (1, 2). Consequently, late diagnosis of PKU still occurs in countries with no NBS programs or without national coverage (3, 4). Immigrants or refugees from countries without NBS or recently implemented NBS programs are at risk for missed diagnoses (4-6). In addition to the lack of national NBS programs, technical issues like false-negative results (5, 7, 8), failures in follow-up procedures (8-10) and cultural circumstances (11) are reported reasons for late diagnosis or delayed treatment of PKU.

source https://www.jpeds.com/article/S0022-3476(21)00855-6/fulltext?rss=yes