Barbero1 nicely details the difficulty undoing the incorrect diagnosis of cystic fibrosis and the, apparently paradoxical, great lengths required to lift the burden of severe chronic disease from families. He observes that the sources of incorrect diagnosis include reliance on screening tests for diagnosis, difficulty of standardization of diagnostic testing, and reliance on clinical diagnosis alone. Not mentioned, however, is another recognized source of false diagnosis and family resistance to reversing the diagnosis of cystic fibrosis. Cystic fibrosis has been reported by Orenstein and Wasserman2 to be the presenting symptom of Munchausen syndrome by proxy (MSBP). In that study, the child's mother went to great lengths to fabricate laboratory evidence to corroborate her false history (MSBP is a syndrome in which the caretaker fabricates history, signs, or symptoms of illness in a child to gain ongoing medical interaction).
Among my personal case consultation series of 90 MSBP victims
Feldman K. False Diagnosis of Cystic Fibrosis. Arch Pediatr Adolesc Med. 1996;150(10):1106-1107. doi:10.1001/archpedi.1996.02170350108024