The Olivier studies 5 confirmed that the prevalence of NTM is particularly high in the southeastern USA, as previously suggested by a study from the adult CF center of the University of North Carolina at Chapel Hill 3 that revealed a prevalence of 19.5%. It is therefore of particular interest that a recent pediatric study from the same medical center 9 retrospectively reviewed CF patients younger than 12 years old and found 6.1% overall prevalence of NTM in BALs over 3 years, and 3.9 % using medical record examination over a 10- year period.